4 This directory contains Device Tree overlays. Device Tree makes it possible
5 to support many hardware configurations with a single kernel and without the
6 need to explicitly load or blacklist kernel modules. Note that this isn't a
7 "pure" Device Tree configuration (c.f. MACH_BCM2835) - some on-board devices
8 are still configured by the board support code, but the intention is to
9 eventually reach that goal.
11 On Raspberry Pi, Device Tree usage is controlled from /boot/config.txt. By
12 default, the Raspberry Pi kernel boots with device tree enabled. You can
13 completely disable DT usage (for now) by adding:
17 to your config.txt, which should cause your Pi to revert to the old way of
18 doing things after a reboot.
20 In /boot you will find a .dtb for each base platform. This describes the
21 hardware that is part of the Raspberry Pi board. The loader (start.elf and its
22 siblings) selects the .dtb file appropriate for the platform by name, and reads
23 it into memory. At this point, all of the optional interfaces (i2c, i2s, spi)
24 are disabled, but they can be enabled using Device Tree parameters:
26 dtparam=i2c=on,i2s=on,spi=on
28 However, this shouldn't be necessary in many use cases because loading an
29 overlay that requires one of those interfaces will cause it to be enabled
30 automatically, and it is advisable to only enable interfaces if they are
33 Configuring additional, optional hardware is done using Device Tree overlays
36 GPIO numbering uses the hardware pin numbering scheme (aka BCM scheme) and
37 not the physical pin numbers.
42 The Advanced Options section of the raspi-config utility can enable and disable
43 Device Tree use, as well as toggling the I2C and SPI interfaces. Note that it
44 is possible to both enable an interface and blacklist the driver, if for some
45 reason you should want to defer the loading.
50 As well as describing the hardware, Device Tree also gives enough information
51 to allow suitable driver modules to be located and loaded, with the corollary
52 that unneeded modules are not loaded. As a result it should be possible to
53 remove lines from /etc/modules, and /etc/modprobe.d/raspi-blacklist.conf can
54 have its contents deleted (or commented out).
59 Overlays are loaded using the "dtoverlay" config.txt setting. As an example,
60 consider I2C Real Time Clock drivers. In the pre-DT world these would be loaded
61 by writing a magic string comprising a device identifier and an I2C address to
62 a special file in /sys/class/i2c-adapter, having first loaded the driver for
63 the I2C interface and the RTC device - something like this:
67 echo ds1307 0x68 > /sys/class/i2c-adapter/i2c-1/new_device
69 With DT enabled, this becomes a line in config.txt:
71 dtoverlay=i2c-rtc,ds1307
73 This causes the file /boot/overlays/i2c-rtc.dtbo to be loaded and a "node"
74 describing the DS1307 I2C device to be added to the Device Tree for the Pi. By
75 default it usees address 0x68, but this can be modified with an additional DT
78 dtoverlay=i2c-rtc,ds1307,addr=0x68
80 Parameters usually have default values, although certain parameters are
81 mandatory. See the list of overlays below for a description of the parameters
84 Making new Overlays based on existing Overlays
85 ==============================================
87 Recent overlays have been designed in a more general way, so that they can be
88 adapted to hardware by changing their parameters. When you have additional
89 hardware with more than one device of a kind, you end up using the same overlay
90 multiple times with other parameters, e.g.
92 # 2 CAN FD interfaces on spi but with different pins
93 dtoverlay=mcp251xfd,spi0-0,interrupt=25
94 dtoverlay=mcp251xfd,spi0-1,interrupt=24
96 # a realtime clock on i2c
97 dtoverlay=i2c-rtc,pcf85063
99 While this approach does work, it requires knowledge about the hardware design.
100 It is more feasible to simplify things for the end user by providing a single
101 overlay as it is done the traditional way.
103 A new overlay can be generated by using ovmerge utility.
104 https://github.com/raspberrypi/utils/blob/master/ovmerge/ovmerge
106 To generate an overlay for the above configuration we pass the configuration
107 to ovmerge and add the -c flag.
109 ovmerge -c mcp251xfd-overlay.dts,spi0-0,interrupt=25 \
110 mcp251xfd-overlay.dts,spi0-1,interrupt=24 \
111 i2c-rtc-overlay.dts,pcf85063 \
112 >> merged-overlay.dts
114 The -c option writes the command above as a comment into the overlay as
115 a marker that this overlay is generated and how it was generated.
116 After compiling the overlay it can be loaded in a single line.
120 It does the same as the original configuration but without parameters.
122 The Overlay and Parameter Reference
123 ===================================
125 N.B. When editing this file, please preserve the indentation levels to make it
126 simple to parse programmatically. NO HARD TABS.
130 Info: Configures the base Raspberry Pi hardware
131 Load: <loaded automatically>
133 ant1 Select antenna 1 (default). CM4 only.
135 ant2 Select antenna 2. CM4 only.
137 noant Disable both antennas. CM4 only.
139 audio Set to "on" to enable the onboard ALSA audio
140 interface (default "off")
142 axiperf Set to "on" to enable the AXI bus performance
144 See /sys/kernel/debug/raspberrypi_axi_monitor
147 bdaddr Set an alternative Bluetooth address (BDADDR).
148 The value should be a 6-byte hexadecimal value,
149 with or without colon separators, written least-
150 significant-byte first. For example,
151 bdaddr=06:05:04:03:02:01
152 will set the BDADDR to 01:02:03:04:05:06.
154 button_debounce Set the debounce delay (in ms) on the power/
155 shutdown button (default 50ms)
157 cam0_reg Enables CAM 0 regulator.
158 Only required on CM1 & 3.
160 cam0_reg_gpio Set GPIO for CAM 0 regulator.
161 Default 31 on CM1, 3, and 4S.
162 Default of GPIO expander 5 on CM4, but override
163 switches to normal GPIO.
165 cam1_reg Enables CAM 1 regulator.
166 Only required on CM1 & 3.
168 cam1_reg_gpio Set GPIO for CAM 1 regulator.
169 Default 3 on CM1, 3, and 4S.
170 Default of GPIO expander 5 on CM4, but override
171 switches to normal GPIO.
173 cooling_fan Enables the Pi 5 cooling fan (enabled
174 automatically by the firmware)
176 drm_fb0_rp1_dpi Assign /dev/fb0 to the RP1 DPI output
178 drm_fb0_rp1_dsi0 Assign /dev/fb0 to the RP1 DSI0 output
180 drm_fb0_rp1_dsi1 Assign /dev/fb0 to the RP1 DSI1 output
182 drm_fb0_vc4 Assign /dev/fb0 to the vc4 outputs
184 drm_fb1_rp1_dpi Assign /dev/fb1 to the RP1 DPI output
186 drm_fb1_rp1_dsi0 Assign /dev/fb1 to the RP1 DSI0 output
188 drm_fb1_rp1_dsi1 Assign /dev/fb1 to the RP1 DSI1 output
190 drm_fb1_vc4 Assign /dev/fb1 to the vc4 outputs
192 drm_fb2_rp1_dpi Assign /dev/fb2 to the RP1 DPI output
194 drm_fb2_rp1_dsi0 Assign /dev/fb2 to the RP1 DSI0 output
196 drm_fb2_rp1_dsi1 Assign /dev/fb2 to the RP1 DSI1 output
198 drm_fb2_vc4 Assign /dev/fb2 to the vc4 outputs
200 eee Enable Energy Efficient Ethernet support for
201 compatible devices (default "on"). See also
202 "tx_lpi_timer". Pi3B+ only.
204 eth_downshift_after Set the number of auto-negotiation failures
205 after which the 1000Mbps modes are disabled.
206 Legal values are 2, 3, 4, 5 and 0, where
207 0 means never downshift (default 2). Pi3B+ only.
209 eth_led0 Set mode of LED0 - amber on Pi3B+ (default "1"),
210 green on Pi4 (default "0").
211 The legal values are:
215 0=link/activity 1=link1000/activity
216 2=link100/activity 3=link10/activity
217 4=link100/1000/activity 5=link10/1000/activity
218 6=link10/100/activity 14=off 15=on
222 0=Speed/Activity 1=Speed
223 2=Flash activity 3=FDX
228 eth_led1 Set mode of LED1 - green on Pi3B+ (default "6"),
229 amber on Pi4 (default "8"). See eth_led0 for
232 eth_max_speed Set the maximum speed a link is allowed
233 to negotiate. Legal values are 10, 100 and
234 1000 (default 1000). Pi3B+ only.
236 hdmi Set to "off" to disable the HDMI interface
239 i2c An alias for i2c_arm
241 i2c_arm Set to "on" to enable the ARM's i2c interface
244 i2c_arm_baudrate Set the baudrate of the ARM's i2c interface
247 i2c_baudrate An alias for i2c_arm_baudrate
249 i2c_csi_dsi Set to "on" to enable the i2c_csi_dsi interface
251 i2c_csi_dsi0 Set to "on" to enable the i2c_csi_dsi0 interface
253 i2c_csi_dsi1 Set to "on" to enable the i2c_csi_dsi1 interface
255 i2c_vc Set to "on" to enable the i2c interface
256 usually reserved for the VideoCore processor
259 i2c_vc_baudrate Set the baudrate of the VideoCore i2c interface
262 i2s Set to "on" to enable the i2s interface
265 i2s_dma4 Use to enable 40-bit DMA on the i2s interface
266 (the assigned value doesn't matter)
269 krnbt Set to "off" to disable autoprobing of Bluetooth
270 driver without need of hciattach/btattach
273 krnbt_baudrate Set the baudrate of the PL011 UART when used
276 nvme Alias for "pciex1" (2712 only)
278 pcie Set to "off" to disable the PCIe interface
280 (2711 only, but not applicable on CM4S)
281 N.B. USB-A ports on 4B are subsequently disabled
283 pcie_tperst_clk_ms Add N milliseconds between PCIe reference clock
284 activation and PERST# deassertion
285 (CM4 and 2712, default "0")
287 pciex1 Set to "on" to enable the external PCIe link
288 (2712 only, default "off")
290 pciex1_gen Sets the PCIe "GEN"/speed for the external PCIe
291 link (2712 only, default "2")
293 pciex1_no_l0s Set to "on" to disable ASPM L0s on the external
294 PCIe link for devices that have broken
295 implementations (2712 only, default "off")
297 pciex1_tperst_clk_ms Alias for pcie_tperst_clk_ms
298 (2712 only, default "0")
300 spi Set to "on" to enable the spi interfaces
303 spi_dma4 Use to enable 40-bit DMA on spi interfaces
304 (the assigned value doesn't matter)
307 random Set to "on" to enable the hardware random
308 number generator (default "on")
310 rtc_bbat_vchg Set the RTC backup battery charging voltage in
311 microvolts. If set to 0 or not specified, the
312 trickle charger is disabled.
313 (2712 only, default "0")
315 sd Set to "off" to disable the SD card (or eMMC on
316 non-lite SKU of CM4).
319 sd_overclock Clock (in MHz) to use when the MMC framework
322 sd_poll_once Looks for a card once after booting. Useful
323 for network booting scenarios to avoid the
324 overhead of continuous polling. N.B. Using
325 this option restricts the system to using a
326 single card per boot (or none at all).
329 sd_force_pio Disable DMA support for SD driver (default off)
331 sd_pio_limit Number of blocks above which to use DMA for
334 sd_debug Enable debug output from SD driver (default off)
336 sdio_overclock Clock (in MHz) to use when the MMC framework
337 requests 50MHz for the SDIO/WLAN interface.
339 suspend Make the power button trigger a suspend rather
340 than a power-off (2712 only, default "off")
342 tx_lpi_timer Set the delay in microseconds between going idle
343 and entering the low power state (default 600).
344 Requires EEE to be enabled - see "eee".
346 uart0 Set to "off" to disable uart0 (default "on")
348 uart0_console Move the kernel boot console to UART0 on pins
349 6, 8 and 10 of the 40-way header (2712 only,
352 uart1 Set to "on" or "off" to enable or disable uart1
355 watchdog Set to "on" to enable the hardware watchdog
358 wifiaddr Set an alternative WiFi MAC address.
359 The value should be a 6-byte hexadecimal value,
360 with or without colon separators, written in the
361 natural (big-endian) order.
363 act_led_trigger Choose which activity the LED tracks.
364 Use "heartbeat" for a nice load indicator.
367 act_led_activelow Set to "on" to invert the sense of the LED
369 N.B. For Pi 3B, 3B+, 3A+ and 4B, use the act-led
372 act_led_gpio Set which GPIO to use for the activity LED
373 (in case you want to connect it to an external
375 (default "16" on a non-Plus board, "47" on a
377 N.B. For Pi 3B, 3B+, 3A+ and 4B, use the act-led
383 As for act_led_*, but using the PWR LED.
384 Not available on Model A/B boards.
386 N.B. It is recommended to only enable those interfaces that are needed.
387 Leaving all interfaces enabled can lead to unwanted behaviour (i2c_vc
388 interfering with Pi Camera, I2S and SPI hogging GPIO pins, etc.)
389 Note also that i2c, i2c_arm and i2c_vc are aliases for the physical
390 interfaces i2c0 and i2c1. Use of the numeric variants is still possible
391 but deprecated because the ARM/VC assignments differ between board
392 revisions. The same board-specific mapping applies to i2c_baudrate,
393 and the other i2c baudrate parameters.
397 Info: Pi 3B, 3B+, 3A+ and 4B use a GPIO expander to drive the LEDs which can
398 only be accessed from the VPU. There is a special driver for this with a
399 separate DT node, which has the unfortunate consequence of breaking the
400 act_led_gpio and act_led_activelow dtparams.
401 This overlay changes the GPIO controller back to the standard one and
402 restores the dtparams.
403 Load: dtoverlay=act-led,<param>=<val>
404 Params: activelow Set to "on" to invert the sense of the LED
407 gpio Set which GPIO to use for the activity LED
408 (in case you want to connect it to an external
413 Name: adafruit-st7735r
414 Info: Overlay for the SPI-connected Adafruit 1.8" 160x128 or 128x128 displays,
415 based on the ST7735R chip.
416 This overlay uses the newer DRM/KMS "Tiny" driver.
417 Load: dtoverlay=adafruit-st7735r,<param>=<val>
418 Params: 128x128 Select the 128x128 driver (default 160x128)
419 rotate Display rotation {0,90,180,270} (default 90)
420 speed SPI bus speed in Hz (default 4000000)
421 dc_pin GPIO pin for D/C (default 24)
422 reset_pin GPIO pin for RESET (default 25)
423 led_pin GPIO used to control backlight (default 18)
427 Info: Overlay for the SPI-connected Adafruit 1.8" display (based on the
428 ST7735R chip). It includes support for the "green tab" version.
429 This overlay uses the older fbtft driver.
430 Load: dtoverlay=adafruit18,<param>=<val>
431 Params: green Use the adafruit18_green variant.
432 rotate Display rotation {0,90,180,270}
433 speed SPI bus speed in Hz (default 4000000)
434 fps Display frame rate in Hz
435 bgr Enable BGR mode (default off)
436 debug Debug output level {0-7}
437 dc_pin GPIO pin for D/C (default 24)
438 reset_pin GPIO pin for RESET (default 25)
439 led_pin GPIO used to control backlight (default 18)
443 Info: Overlay for activation of ADAU1977 ADC codec over I2C for control
445 Load: dtoverlay=adau1977-adc
449 Name: adau7002-simple
450 Info: Overlay for the activation of ADAU7002 stereo PDM to I2S converter.
451 Load: dtoverlay=adau7002-simple,<param>=<val>
452 Params: card-name Override the default, "adau7002", card name.
456 Info: Overlay for activation of Texas Instruments ADS1015 ADC over I2C
457 Load: dtoverlay=ads1015,<param>=<val>
458 Params: addr I2C bus address of device. Set based on how the
459 addr pin is wired. (default=0x48 assumes addr
461 cha_enable Enable virtual channel a. (default=true)
462 cha_cfg Set the configuration for virtual channel a.
463 (default=4 configures this channel for the
464 voltage at A0 with respect to GND)
465 cha_datarate Set the datarate (samples/sec) for this channel.
466 (default=4 sets 1600 sps)
467 cha_gain Set the gain of the Programmable Gain
468 Amplifier for this channel. (default=2 sets the
469 full scale of the channel to 2.048 Volts)
471 Channel (ch) parameters can be set for each enabled channel.
472 A maximum of 4 channels can be enabled (letters a thru d).
473 For more information refer to the device datasheet at:
474 http://www.ti.com/lit/ds/symlink/ads1015.pdf
478 Info: Texas Instruments ADS1115 ADC
479 Load: dtoverlay=ads1115,<param>[=<val>]
480 Params: addr I2C bus address of device. Set based on how the
481 addr pin is wired. (default=0x48 assumes addr
483 cha_enable Enable virtual channel a.
484 cha_cfg Set the configuration for virtual channel a.
485 (default=4 configures this channel for the
486 voltage at A0 with respect to GND)
487 cha_datarate Set the datarate (samples/sec) for this channel.
488 (default=7 sets 860 sps)
489 cha_gain Set the gain of the Programmable Gain
490 Amplifier for this channel. (Default 1 sets the
491 full scale of the channel to 4.096 Volts)
492 i2c0 Choose the I2C0 bus on GPIOs 0&1
493 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
494 i2c3 Choose the I2C3 bus (configure with the i2c3
495 overlay - BCM2711 only)
496 i2c4 Choose the I2C4 bus (configure with the i2c4
497 overlay - BCM2711 only)
498 i2c5 Choose the I2C5 bus (configure with the i2c5
499 overlay - BCM2711 only)
500 i2c6 Choose the I2C6 bus (configure with the i2c6
501 overlay - BCM2711 only)
503 Channel parameters can be set for each enabled channel.
504 A maximum of 4 channels can be enabled (letters a thru d).
505 For more information refer to the device datasheet at:
506 http://www.ti.com/lit/ds/symlink/ads1115.pdf
510 Info: ADS7846 Touch controller
511 Load: dtoverlay=ads7846,<param>=<val>
512 Params: cs SPI bus Chip Select (default 1)
513 speed SPI bus speed (default 2MHz, max 3.25MHz)
514 penirq GPIO used for PENIRQ. REQUIRED
515 penirq_pull Set GPIO pull (default 0=none, 2=pullup)
516 swapxy Swap x and y axis
517 xmin Minimum value on the X axis (default 0)
518 ymin Minimum value on the Y axis (default 0)
519 xmax Maximum value on the X axis (default 4095)
520 ymax Maximum value on the Y axis (default 4095)
521 pmin Minimum reported pressure value (default 0)
522 pmax Maximum reported pressure value (default 65535)
523 xohms Touchpanel sensitivity (X-plate resistance)
526 penirq is required and usually xohms (60-100) has to be set as well.
527 Apart from that, pmax (255) and swapxy are also common.
528 The rest of the calibration can be done with xinput-calibrator.
529 See: github.com/notro/fbtft/wiki/FBTFT-on-Raspian
530 Device Tree binding document:
531 www.kernel.org/doc/Documentation/devicetree/bindings/input/ads7846.txt
535 Info: Analog Devices ADV7282M analogue video to CSI2 bridge.
536 Uses Unicam1, which is the standard camera connector on most Pi
538 Load: dtoverlay=adv7282m,<param>=<val>
539 Params: addr Overrides the I2C address (default 0x21)
540 media-controller Configure use of Media Controller API for
541 configuring the sensor (default off)
545 Info: Analog Devices ADV728[0|1|2]-M analogue video to CSI2 bridges.
546 This is a wrapper for adv7282m, and defaults to ADV7282M.
547 Load: dtoverlay=adv728x-m,<param>=<val>
548 Params: addr Overrides the I2C address (default 0x21)
549 adv7280m Select ADV7280-M.
550 adv7281m Select ADV7281-M.
551 adv7281ma Select ADV7281-MA.
552 media-controller Configure use of Media Controller API for
553 configuring the sensor (default off)
556 Name: akkordion-iqdacplus
557 Info: Configures the Digital Dreamtime Akkordion Music Player (based on the
558 OEM IQAudIO DAC+ or DAC Zero module).
559 Load: dtoverlay=akkordion-iqdacplus,<param>=<val>
560 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
561 Digital volume control. Enable with
562 dtoverlay=akkordion-iqdacplus,24db_digital_gain
563 (The default behaviour is that the Digital
564 volume control is limited to a maximum of
565 0dB. ie. it can attenuate but not provide
566 gain. For most users, this will be desired
567 as it will prevent clipping. By appending
568 the 24db_digital_gain parameter, the Digital
569 volume control will allow up to 24dB of
570 gain. If this parameter is enabled, it is the
571 responsibility of the user to ensure that
572 the Digital volume control is set to a value
573 that does not result in clipping/distortion!)
576 Name: allo-boss-dac-pcm512x-audio
577 Info: Configures the Allo Boss DAC audio cards.
578 Load: dtoverlay=allo-boss-dac-pcm512x-audio,<param>
579 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
580 Digital volume control. Enable with
581 "dtoverlay=allo-boss-dac-pcm512x-audio,
583 (The default behaviour is that the Digital
584 volume control is limited to a maximum of
585 0dB. ie. it can attenuate but not provide
586 gain. For most users, this will be desired
587 as it will prevent clipping. By appending
588 the 24db_digital_gain parameter, the Digital
589 volume control will allow up to 24dB of
590 gain. If this parameter is enabled, it is the
591 responsibility of the user to ensure that
592 the Digital volume control is set to a value
593 that does not result in clipping/distortion!)
594 slave Force Boss DAC into slave mode, using Pi a
595 master for bit clock and frame clock. Enable
596 with "dtoverlay=allo-boss-dac-pcm512x-audio,
600 Name: allo-boss2-dac-audio
601 Info: Configures the Allo Boss2 DAC audio card
602 Load: dtoverlay=allo-boss2-dac-audio
607 Info: Configures the Allo Digione audio card
608 Load: dtoverlay=allo-digione
612 Name: allo-katana-dac-audio
613 Info: Configures the Allo Katana DAC audio card
614 Load: dtoverlay=allo-katana-dac-audio
618 Name: allo-piano-dac-pcm512x-audio
619 Info: Configures the Allo Piano DAC (2.0/2.1) audio cards.
620 (NB. This initial support is for 2.0 channel audio ONLY! ie. stereo.
621 The subwoofer outputs on the Piano 2.1 are not currently supported!)
622 Load: dtoverlay=allo-piano-dac-pcm512x-audio,<param>
623 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
624 Digital volume control.
625 (The default behaviour is that the Digital
626 volume control is limited to a maximum of
627 0dB. ie. it can attenuate but not provide
628 gain. For most users, this will be desired
629 as it will prevent clipping. By appending
630 the 24db_digital_gain parameter, the Digital
631 volume control will allow up to 24dB of
632 gain. If this parameter is enabled, it is the
633 responsibility of the user to ensure that
634 the Digital volume control is set to a value
635 that does not result in clipping/distortion!)
638 Name: allo-piano-dac-plus-pcm512x-audio
639 Info: Configures the Allo Piano DAC (2.1) audio cards.
640 Load: dtoverlay=allo-piano-dac-plus-pcm512x-audio,<param>
641 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
642 Digital volume control.
643 (The default behaviour is that the Digital
644 volume control is limited to a maximum of
645 0dB. ie. it can attenuate but not provide
646 gain. For most users, this will be desired
647 as it will prevent clipping. By appending
648 the 24db_digital_gain parameter, the Digital
649 volume control will allow up to 24dB of
650 gain. If this parameter is enabled, it is the
651 responsibility of the user to ensure that
652 the Digital volume control is set to a value
653 that does not result in clipping/distortion!)
654 glb_mclk This option is only with Kali board. If enabled,
655 MCLK for Kali is used and PLL is disabled for
656 better voice quality. (default Off)
660 Info: Universal device tree overlay for SPI devices
662 Just specify the SPI address and device name ("compatible" property).
663 This overlay lacks any device-specific parameter support!
665 For devices on spi1 or spi2, the interfaces should be enabled
666 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
669 1. SPI NOR flash on spi0.1, maximum SPI clock frequency 45MHz:
670 dtoverlay=anyspi:spi0-1,dev="jedec,spi-nor",speed=45000000
671 2. MCP3204 ADC on spi1.2, maximum SPI clock frequency 500kHz:
672 dtoverlay=anyspi:spi1-2,dev="microchip,mcp3204"
673 Load: dtoverlay=anyspi,<param>=<val>
674 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
676 dev Set device name to search compatible module
678 speed Set SPI clock frequency in Hz
679 (integer, optional, default 500000)
683 Info: Configures the AVAGO APDS9960 digital proximity, ambient light, RGB and
685 Load: dtoverlay=apds9960,<param>=<val>
686 Params: gpiopin GPIO used for INT (default 4)
687 noints Disable the interrupt GPIO line.
691 Info: Configures the Orchard Audio ApplePi-DAC audio card
692 Load: dtoverlay=applepi-dac
697 Info: Arducam 64MP camera module.
698 Uses Unicam 1, which is the standard camera connector on most Pi
700 Load: dtoverlay=arducam-64mp,<param>=<val>
701 Params: rotation Mounting rotation of the camera sensor (0 or
703 orientation Sensor orientation (0 = front, 1 = rear,
704 2 = external, default external)
705 media-controller Configure use of Media Controller API for
706 configuring the sensor (default on)
707 cam0 Adopt the default configuration for CAM0 on a
708 Compute Module (CSI0, i2c_vc, and cam0_reg).
709 vcm Select lens driver state. Default is enabled,
710 but vcm=off will disable.
713 Name: arducam-pivariety
714 Info: Arducam Pivariety camera module.
715 Uses Unicam 1, which is the standard camera connector on most Pi
717 Load: dtoverlay=arducam-pivariety,<param>=<val>
718 Params: rotation Mounting rotation of the camera sensor (0 or
720 orientation Sensor orientation (0 = front, 1 = rear,
721 2 = external, default external)
722 media-controller Configure use of Media Controller API for
723 configuring the sensor (default on)
724 cam0 Adopt the default configuration for CAM0 on a
725 Compute Module (CSI0, i2c_vc, and cam0_reg).
729 Info: Configures the Atmel AT86RF233 802.15.4 low-power WPAN transceiver,
731 Load: dtoverlay=at86rf233,<param>=<val>
732 Params: interrupt GPIO used for INT (default 23)
733 reset GPIO used for Reset (default 24)
734 sleep GPIO used for Sleep (default 25)
735 speed SPI bus speed in Hz (default 3000000)
736 trim Fine tuning of the internal capacitance
737 arrays (0=+0pF, 15=+4.5pF, default 15)
740 Name: audioinjector-addons
741 Info: Configures the audioinjector.net audio add on soundcards
742 Load: dtoverlay=audioinjector-addons,<param>=<val>
743 Params: non-stop-clocks Keeps the clocks running even when the stream
744 is paused or stopped (default off)
747 Name: audioinjector-bare-i2s
748 Info: Configures the audioinjector.net audio bare i2s soundcard
749 Load: dtoverlay=audioinjector-bare-i2s
753 Name: audioinjector-isolated-soundcard
754 Info: Configures the audioinjector.net isolated soundcard
755 Load: dtoverlay=audioinjector-isolated-soundcard
759 Name: audioinjector-ultra
760 Info: Configures the audioinjector.net ultra soundcard
761 Load: dtoverlay=audioinjector-ultra
765 Name: audioinjector-wm8731-audio
766 Info: Configures the audioinjector.net audio add on soundcard
767 Load: dtoverlay=audioinjector-wm8731-audio
772 Info: Configures the audiosense-pi add on soundcard
773 For more information refer to
774 https://gitlab.com/kakar0t/audiosense-pi
775 Load: dtoverlay=audiosense-pi
780 Info: Switches PWM sound output to GPIOs on the 40-pin header
781 Load: dtoverlay=audremap,<param>=<val>
782 Params: swap_lr Reverse the channel allocation, which will also
783 swap the audio jack outputs (default off)
784 enable_jack Don't switch off the audio jack output. Does
785 nothing on BCM2711 (default off)
786 pins_12_13 Select GPIOs 12 & 13 (default)
787 pins_18_19 Select GPIOs 18 & 19
788 pins_40_41 Select GPIOs 40 & 41 (not available on CM4, used
790 pins_40_45 Select GPIOs 40 & 45 (don't use on BCM2711 - the
791 pins are on different controllers)
795 Info: Overlay that enables WLAN, Bluetooth and the GPIO expander on the
796 balenaFin carrier board for the Raspberry Pi Compute Module 3/3+ Lite.
797 Load: dtoverlay=balena-fin
801 Name: bmp085_i2c-sensor
802 Info: This overlay is now deprecated - see i2c-sensor
806 Name: camera-mux-2port
807 Info: Configures a 2 port camera multiplexer
808 Note that currently ALL IMX290 modules share a common clock, therefore
809 all modules will need to have the same clock frequency.
810 Load: dtoverlay=camera-mux-2port,<param>=<val>
811 Params: cam0-arducam-64mp Select Arducam64MP for camera on port 0
812 cam0-imx219 Select IMX219 for camera on port 0
813 cam0-imx258 Select IMX258 for camera on port 0
814 cam0-imx290 Select IMX290 for camera on port 0
815 cam0-imx477 Select IMX477 for camera on port 0
816 cam0-imx519 Select IMX519 for camera on port 0
817 cam0-imx708 Select IMX708 for camera on port 0
818 cam0-ov2311 Select OV2311 for camera on port 0
819 cam0-ov5647 Select OV5647 for camera on port 0
820 cam0-ov64a40 Select OV64A40 for camera on port 0
821 cam0-ov7251 Select OV7251 for camera on port 0
822 cam0-ov9281 Select OV9281 for camera on port 0
823 cam0-imx290-clk-freq Set clock frequency for an IMX290 on port 0
824 cam1-arducam-64mp Select Arducam64MP for camera on port 1
825 cam1-imx219 Select IMX219 for camera on port 1
826 cam1-imx258 Select IMX258 for camera on port 1
827 cam1-imx290 Select IMX290 for camera on port 1
828 cam1-imx477 Select IMX477 for camera on port 1
829 cam1-imx519 Select IMX519 for camera on port 1
830 cam1-imx708 Select IMX708 for camera on port 1
831 cam1-ov2311 Select OV2311 for camera on port 1
832 cam1-ov5647 Select OV5647 for camera on port 1
833 cam1-ov64a40 Select OV64A40 for camera on port 1
834 cam1-ov7251 Select OV7251 for camera on port 1
835 cam1-ov9281 Select OV9281 for camera on port 1
836 cam1-imx290-clk-freq Set clock frequency for an IMX290 on port 1
838 cam0 Connect the mux to CAM0 port (default is CAM1)
841 Name: camera-mux-4port
842 Info: Configures a 4 port camera multiplexer
843 Note that currently ALL IMX290 modules share a common clock, therefore
844 all modules will need to have the same clock frequency.
845 Load: dtoverlay=camera-mux-4port,<param>=<val>
846 Params: cam0-arducam-64mp Select Arducam64MP for camera on port 0
847 cam0-imx219 Select IMX219 for camera on port 0
848 cam0-imx258 Select IMX258 for camera on port 0
849 cam0-imx290 Select IMX290 for camera on port 0
850 cam0-imx477 Select IMX477 for camera on port 0
851 cam0-imx519 Select IMX519 for camera on port 0
852 cam0-imx708 Select IMX708 for camera on port 0
853 cam0-ov2311 Select OV2311 for camera on port 0
854 cam0-ov5647 Select OV5647 for camera on port 0
855 cam0-ov64a40 Select OV64A40 for camera on port 0
856 cam0-ov7251 Select OV7251 for camera on port 0
857 cam0-ov9281 Select OV9281 for camera on port 0
858 cam0-imx290-clk-freq Set clock frequency for an IMX290 on port 0
859 cam1-arducam-64mp Select Arducam64MP for camera on port 1
860 cam1-imx219 Select IMX219 for camera on port 1
861 cam1-imx258 Select IMX258 for camera on port 1
862 cam1-imx290 Select IMX290 for camera on port 1
863 cam1-imx477 Select IMX477 for camera on port 1
864 cam1-imx519 Select IMX519 for camera on port 1
865 cam1-imx708 Select IMX708 for camera on port 1
866 cam1-ov2311 Select OV2311 for camera on port 1
867 cam1-ov5647 Select OV5647 for camera on port 1
868 cam1-ov64a40 Select OV64A40 for camera on port 1
869 cam1-ov7251 Select OV7251 for camera on port 1
870 cam1-ov9281 Select OV9281 for camera on port 1
871 cam1-imx290-clk-freq Set clock frequency for an IMX290 on port 1
872 cam2-arducam-64mp Select Arducam64MP for camera on port 2
873 cam2-imx219 Select IMX219 for camera on port 2
874 cam2-imx258 Select IMX258 for camera on port 2
875 cam2-imx290 Select IMX290 for camera on port 2
876 cam2-imx477 Select IMX477 for camera on port 2
877 cam2-imx519 Select IMX519 for camera on port 2
878 cam2-imx708 Select IMX708 for camera on port 2
879 cam2-ov2311 Select OV2311 for camera on port 2
880 cam2-ov5647 Select OV5647 for camera on port 2
881 cam2-ov64a40 Select OV64A40 for camera on port 2
882 cam2-ov7251 Select OV7251 for camera on port 2
883 cam2-ov9281 Select OV9281 for camera on port 2
884 cam2-imx290-clk-freq Set clock frequency for an IMX290 on port 2
885 cam3-arducam-64mp Select Arducam64MP for camera on port 3
886 cam3-imx219 Select IMX219 for camera on port 3
887 cam3-imx258 Select IMX258 for camera on port 3
888 cam3-imx290 Select IMX290 for camera on port 3
889 cam3-imx477 Select IMX477 for camera on port 3
890 cam3-imx519 Select IMX519 for camera on port 3
891 cam3-imx708 Select IMX708 for camera on port 3
892 cam3-ov2311 Select OV2311 for camera on port 3
893 cam3-ov5647 Select OV5647 for camera on port 3
894 cam3-ov64a40 Select OV64A40 for camera on port 3
895 cam3-ov7251 Select OV7251 for camera on port 3
896 cam3-ov9281 Select OV9281 for camera on port 3
897 cam3-imx290-clk-freq Set clock frequency for an IMX290 on port 3
899 cam0 Connect the mux to CAM0 port (default is CAM1)
903 Info: Enables the ability to use the cap1106 touch sensor as a keyboard
904 Load: dtoverlay=cap1106,<param>=<val>
905 Params: int_pin GPIO pin for interrupt signal (default 23)
909 Info: Configures Chip Dip audio cards.
910 Load: dtoverlay=chipdip-dac
915 Info: Configures the Cirrus Logic Audio Card
916 Load: dtoverlay=cirrus-wm5102
921 Info: Largely for Compute Modules 1&3 where the original instructions for
922 adding a camera used GPIOs 0&1 for CAM1 and 28&29 for CAM0, whilst all
923 other platforms use 28&29 (or 44&45) for CAM1.
924 The default assignment through using this overlay is for
925 i2c0 to use 28&29, and i2c10 (aka i2c_csi_dsi) to use 28&29, but the
926 overrides allow this to be changed.
927 Load: dtoverlay=cm-swap-i2c0,<param>=<val>
928 Params: i2c0-gpio0 Use GPIOs 0&1 for i2c0
929 i2c0-gpio28 Use GPIOs 28&29 for i2c0 (default)
930 i2c0-gpio44 Use GPIOs 44&45 for i2c0
931 i2c10-gpio0 Use GPIOs 0&1 for i2c0 (default)
932 i2c10-gpio28 Use GPIOs 28&29 for i2c0
933 i2c10-gpio44 Use GPIOs 44&45 for i2c0
937 Info: Set custom CMA sizes, only use if you know what you are doing, might
938 clash with other overlays like vc4-fkms-v3d and vc4-kms-v3d.
939 Load: dtoverlay=cma,<param>=<val>
940 Params: cma-512 CMA is 512MB (needs 1GB)
941 cma-448 CMA is 448MB (needs 1GB)
942 cma-384 CMA is 384MB (needs 1GB)
943 cma-320 CMA is 320MB (needs 1GB)
944 cma-256 CMA is 256MB (needs 1GB)
945 cma-192 CMA is 192MB (needs 1GB)
949 cma-size CMA size in bytes, 4MB aligned
950 cma-default Use upstream's default value
953 Name: crystalfontz-cfa050_pi_m
954 Info: Configures the Crystalfontz CFA050-PI-M series of Raspberry Pi CM4
955 based modules using the CFA7201280A0_050Tx 7" TFT LCD displays,
956 with or without capacitive touch screen.
957 Requires use of vc4-kms-v3d.
958 Load: dtoverlay=crystalfontz-cfa050_pi_m,<param>=<val>
959 Params: captouch Enable capacitive touch display
963 Info: 8" TFT LCD display and touch panel used by cutiepi.io
964 Load: dtoverlay=cutiepi-panel
969 Info: Configures the dacberry400 add on soundcard
970 Load: dtoverlay=dacberry400
975 Info: Overlay for the DHT11/DHT21/DHT22 humidity/temperature sensors
976 Also sometimes found with the part number(s) AM230x.
977 Load: dtoverlay=dht11,<param>=<val>
978 Params: gpiopin GPIO connected to the sensor's DATA output.
983 Info: Configures the Dion Audio KIWI STREAMER
984 Load: dtoverlay=dionaudio-kiwi
989 Info: Configures the Dion Audio LOCO DAC-AMP
990 Load: dtoverlay=dionaudio-loco
994 Name: dionaudio-loco-v2
995 Info: Configures the Dion Audio LOCO-V2 DAC-AMP
996 Load: dtoverlay=dionaudio-loco-v2,<param>=<val>
997 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
998 Digital volume control. Enable with
999 "dtoverlay=hifiberry-dacplus,24db_digital_gain"
1000 (The default behaviour is that the Digital
1001 volume control is limited to a maximum of
1002 0dB. ie. it can attenuate but not provide
1003 gain. For most users, this will be desired
1004 as it will prevent clipping. By appending
1005 the 24dB_digital_gain parameter, the Digital
1006 volume control will allow up to 24dB of
1007 gain. If this parameter is enabled, it is the
1008 responsibility of the user to ensure that
1009 the Digital volume control is set to a value
1010 that does not result in clipping/distortion!)
1014 Info: Disable onboard Bluetooth on Bluetooth-capable Raspberry Pis. On Pis
1015 prior to Pi 5 this restores UART0/ttyAMA0 over GPIOs 14 & 15.
1016 Load: dtoverlay=disable-bt
1020 Name: disable-bt-pi5
1021 Info: See disable-bt
1025 Info: Disable EMMC2 controller on BCM2711.
1026 The allows the onboard EMMC storage on Compute Module 4 to be disabled
1027 e.g. if a fault has occurred.
1028 Load: dtoverlay=disable-emmc2
1033 Info: Disable onboard WLAN on WiFi-capable Raspberry Pis.
1034 Load: dtoverlay=disable-wifi
1038 Name: disable-wifi-pi5
1039 Info: See disable-wifi
1043 Info: Overlay for a generic 18-bit DPI display
1044 This uses GPIOs 0-21 (so no I2C, uart etc.), and activates the output
1045 2-3 seconds after the kernel has started.
1046 Load: dtoverlay=dpi18
1051 Info: Overlay for a generic 18-bit DPI display (in 'mode 6' connection scheme)
1052 This uses GPIOs 0-9,12-17,20-25 (so no I2C, uart etc.), and activates
1053 the output 3-3 seconds after the kernel has started.
1054 Load: dtoverlay=dpi18cpadhi
1059 Info: Overlay for a generic 24-bit DPI display
1060 This uses GPIOs 0-27 (so no I2C, uart etc.), and activates the output
1061 2-3 seconds after the kernel has started.
1062 Load: dtoverlay=dpi24
1067 Info: Configures the NW Digital Radio DRAWS Hat
1069 The board includes an ADC to measure various board values and also
1070 provides two analog user inputs on the expansion header. The ADC
1071 can be configured for various sample rates and gain values to adjust
1072 the input range. Tables describing the two parameters follow.
1084 ADC Datarate Values:
1089 4 = 1600sps (default)
1093 Load: dtoverlay=draws,<param>=<val>
1094 Params: draws_adc_ch4_gain Sets the full scale resolution of the ADCs
1095 input voltage sensor (default 1)
1097 draws_adc_ch4_datarate Sets the datarate of the ADCs input voltage
1100 draws_adc_ch5_gain Sets the full scale resolution of the ADCs
1101 5V rail voltage sensor (default 1)
1103 draws_adc_ch5_datarate Sets the datarate of the ADCs 4V rail voltage
1106 draws_adc_ch6_gain Sets the full scale resolution of the ADCs
1107 AIN2 input (default 2)
1109 draws_adc_ch6_datarate Sets the datarate of the ADCs AIN2 input
1111 draws_adc_ch7_gain Sets the full scale resolution of the ADCs
1112 AIN3 input (default 2)
1114 draws_adc_ch7_datarate Sets the datarate of the ADCs AIN3 input
1116 alsaname Name of the ALSA audio device (default "draws")
1120 Info: Selects the dwc_otg USB controller driver which has fiq support. This
1121 is the default on all except the Pi Zero which defaults to dwc2.
1122 Load: dtoverlay=dwc-otg
1127 Info: Selects the dwc2 USB controller driver
1128 Load: dtoverlay=dwc2,<param>=<val>
1129 Params: dr_mode Dual role mode: "host", "peripheral" or "otg"
1131 g-rx-fifo-size Size of rx fifo size in gadget mode
1133 g-np-tx-fifo-size Size of non-periodic tx fifo size in gadget
1137 [ The ds1307-rtc overlay has been deleted. See i2c-rtc. ]
1141 Info: Overlay for the EDT FT5406 touchscreen.
1142 This works with the Raspberry Pi 7" touchscreen when not being polled
1144 By default the overlay uses the i2c_csi_dsi I2C interface, but this
1146 You MUST use either "disable_touchscreen=1" or "ignore_lcd=1" in
1147 config.txt to stop the firmware polling the touchscreen.
1148 Load: dtoverlay=edt-ft5406,<param>=<val>
1149 Params: sizex Touchscreen size x (default 800)
1150 sizey Touchscreen size y (default 480)
1151 invx Touchscreen inverted x axis
1152 invy Touchscreen inverted y axis
1153 swapxy Touchscreen swapped x y axis
1154 i2c0 Choose the I2C0 bus on GPIOs 0&1
1155 i2c1 Choose the I2C1 bus on GPIOs 2&3
1156 i2c3 Choose the I2C3 bus (configure with the i2c3
1157 overlay - BCM2711 only)
1158 i2c4 Choose the I2C4 bus (configure with the i2c4
1159 overlay - BCM2711 only)
1160 i2c5 Choose the I2C5 bus (configure with the i2c5
1161 overlay - BCM2711 only)
1162 i2c6 Choose the I2C6 bus (configure with the i2c6
1163 overlay - BCM2711 only)
1164 addr Sets the address for the touch controller. Note
1165 that the device must be configured to use the
1170 Info: Overlay for the Microchip ENC28J60 Ethernet Controller on SPI0
1171 Load: dtoverlay=enc28j60,<param>=<val>
1172 Params: int_pin GPIO used for INT (default 25)
1174 speed SPI bus speed (default 12000000)
1178 Info: Overlay for the Microchip ENC28J60 Ethernet Controller on SPI2
1179 Load: dtoverlay=enc28j60-spi2,<param>=<val>
1180 Params: int_pin GPIO used for INT (default 39)
1182 speed SPI bus speed (default 12000000)
1186 Info: Enables I2C connected EETI EXC3000 multiple touch controller using
1187 GPIO 4 (pin 7 on GPIO header) for interrupt.
1188 Load: dtoverlay=exc3000,<param>=<val>
1189 Params: interrupt GPIO used for interrupt (default 4)
1190 sizex Touchscreen size x (default 4096)
1191 sizey Touchscreen size y (default 4096)
1192 invx Touchscreen inverted x axis
1193 invy Touchscreen inverted y axis
1194 swapxy Touchscreen swapped x y axis
1198 Info: Overlay for SPI-connected displays using the fbtft drivers.
1200 This overlay seeks to replace the functionality provided by fbtft_device
1201 which is now gone from the kernel.
1203 Most displays from fbtft_device have been ported over.
1205 dtoverlay=fbtft,spi0-0,rpi-display,reset_pin=23,dc_pin=24,led_pin=18,rotate=270
1207 It is also possible to specify the controller (this will use the default
1208 init sequence in the driver).
1210 dtoverlay=fbtft,spi0-0,ili9341,bgr,reset_pin=23,dc_pin=24,led_pin=18,rotate=270
1212 For devices on spi1 or spi2, the interfaces should be enabled
1213 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
1215 The following features of fbtft_device have not been ported over:
1216 - parallel bus is not supported
1217 - the init property which overrides the controller initialization
1218 sequence is not supported as a parameter due to memory limitations in
1219 the bootloader responsible for applying the overlay.
1221 See https://github.com/notro/fbtft/wiki/FBTFT-RPI-overlays for how to
1224 Load: dtoverlay=fbtft,<param>=<val>
1226 spi<n>-<m> Configure device at spi<n>, cs<m>
1228 speed SPI bus speed in Hz (default 32000000)
1229 cpha Shifted clock phase (CPHA) mode
1230 cpol Inverse clock polarity (CPOL) mode
1232 adafruit18 Adafruit 1.8
1233 adafruit22 Adafruit 2.2 (old)
1234 adafruit22a Adafruit 2.2
1235 adafruit28 Adafruit 2.8
1236 adafruit13m Adafruit 1.3 OLED
1237 admatec_c-berry28 C-Berry28
1239 er_tftm050_2 ER-TFTM070-2
1240 er_tftm070_5 ER-TFTM070-5
1242 ew24ha0_9bit EW24HA0 in 9-bit mode
1243 freetronicsoled128 Freetronics OLED128
1246 itdb28_spi ITDB02-2.8 with SPI interface circuit
1247 mi0283qt-2 Watterott MI0283QT-2
1248 mi0283qt-9a Watterott MI0283QT-9A
1249 nokia3310 Nokia 3310
1250 nokia3310a Nokia 3310a
1251 nokia5110 Nokia 5110
1253 pitft Adafruit PiTFT 2.8
1255 rpi-display Watterott rpi-display
1256 sainsmart18 Sainsmart 1.8
1257 sainsmart32_spi Sainsmart 3.2 with SPI interfce circuit
1258 tinylcd35 TinyLCD 3.5
1259 tm022hdh26 Tianma TM022HDH26
1260 tontec35_9481 Tontect 3.5 with ILI9481 controller
1261 tontec35_9486 Tontect 3.5 with ILI9486 controller
1262 waveshare32b Waveshare 3.2
1263 waveshare22 Waveshare 2.2
1265 bd663474 BD663474 display controller
1266 hx8340bn HX8340BN display controller
1267 hx8347d HX8347D display controller
1268 hx8353d HX8353D display controller
1269 hx8357d HX8357D display controller
1270 ili9163 ILI9163 display controller
1271 ili9320 ILI9320 display controller
1272 ili9325 ILI9325 display controller
1273 ili9340 ILI9340 display controller
1274 ili9341 ILI9341 display controller
1275 ili9481 ILI9481 display controller
1276 ili9486 ILI9486 display controller
1277 pcd8544 PCD8544 display controller
1278 ra8875 RA8875 display controller
1279 s6d02a1 S6D02A1 display controller
1280 s6d1121 S6D1121 display controller
1281 seps525 SEPS525 display controller
1282 sh1106 SH1106 display controller
1283 ssd1289 SSD1289 display controller
1284 ssd1305 SSD1305 display controller
1285 ssd1306 SSD1306 display controller
1286 ssd1325 SSD1325 display controller
1287 ssd1331 SSD1331 display controller
1288 ssd1351 SSD1351 display controller
1289 st7735r ST7735R display controller
1290 st7789v ST7789V display controller
1291 tls8204 TLS8204 display controller
1292 uc1611 UC1611 display controller
1293 uc1701 UC1701 display controller
1294 upd161704 UPD161704 display controller
1296 width Display width in pixels
1297 height Display height in pixels
1298 regwidth Display controller register width (default is
1300 buswidth Display bus interface width (default 8)
1301 debug Debug output level {0-7}
1302 rotate Display rotation {0, 90, 180, 270} (counter
1303 clockwise). Not supported by all drivers.
1304 bgr Enable BGR mode (default off). Use if Red and
1305 Blue are swapped. Not supported by all drivers.
1306 fps Frames per second (default 30). In effect this
1307 states how long the driver will wait after video
1308 memory has been changed until display update
1309 transfer is started.
1310 txbuflen Length of the FBTFT transmit buffer
1312 startbyte Sets the Start byte used by fb_ili9320,
1313 fb_ili9325 and fb_hx8347d. Common value is 0x70.
1314 gamma String representation of Gamma Curve(s). Driver
1315 specific. Not supported by all drivers.
1316 reset_pin GPIO pin for RESET
1317 dc_pin GPIO pin for D/C
1318 led_pin GPIO pin for LED backlight
1322 Info: Configures the Fe-Pi Audio Sound Card
1323 Load: dtoverlay=fe-pi-audio
1328 Info: A demonstration of the gpio-fsm driver. The GPIOs are chosen to work
1329 nicely with a "traffic-light" display of red, amber and green LEDs on
1330 GPIOs 7, 8 and 25 respectively.
1331 Load: dtoverlay=fsm-demo,<param>=<val>
1332 Params: fsm_debug Enable debug logging (default off)
1336 Info: Enables GalaxyCore's GC9A01 single chip driver based displays on
1337 SPI0 as fb1, using GPIOs DC=25, RST=27 and BL=18 (physical
1338 GPIO header pins 22, 13 and 12 respectively) in addition to the
1339 SPI0 pins DIN=10, CLK=11 and CS=8 (physical GPIO header pins 19,
1340 23 and 24 respectively).
1341 Load: dtoverlay=gc9a01,<param>=<val>
1342 Params: speed Display SPI bus speed
1344 rotate Display rotation {0,90,180,270}
1346 width Width of the display
1348 height Height of the display
1350 fps Delay between frame updates
1352 debug Debug output level {0-7}
1356 Info: An overlay for the Ghost amplifier.
1357 Load: dtoverlay=ghost-amp,<param>=<val>
1358 Params: fsm_debug Enable debug logging of the GPIO FSM (default
1363 Info: Enables I2C connected Goodix gt9271 multiple touch controller using
1364 GPIOs 4 and 17 (pins 7 and 11 on GPIO header) for interrupt and reset.
1365 Load: dtoverlay=goodix,<param>=<val>
1366 Params: interrupt GPIO used for interrupt (default 4)
1367 reset GPIO used for reset (default 17)
1370 Name: googlevoicehat-soundcard
1371 Info: Configures the Google voiceHAT soundcard
1372 Load: dtoverlay=googlevoicehat-soundcard
1377 Info: This is a generic overlay for detecting charger with GPIO.
1378 Load: dtoverlay=gpio-charger,<param>=<val>
1379 Params: gpio GPIO pin to trigger on (default 4)
1380 active_low When this is 1 (active low), a falling
1381 edge generates a charging event and a
1382 rising edge generates a discharging event.
1383 When this is 0 (active high), this is
1384 reversed. The default is 0 (active high)
1385 gpio_pull Desired pull-up/down state (off, down, up)
1387 type Set a charger type for the pin. (Default: mains)
1391 Info: Configure a GPIO pin to control a cooling fan.
1392 Load: dtoverlay=gpio-fan,<param>=<val>
1393 Params: gpiopin GPIO used to control the fan (default 12)
1394 temp Temperature at which the fan switches on, in
1395 millicelcius (default 55000)
1396 hyst Temperature delta (in millicelcius) below
1397 temp at which the fan will drop to minrpm
1402 Info: Activate a "hog" for a GPIO - request that the kernel configures it as
1403 an output, driven low or high as indicated by the presence or absence
1404 of the active_low parameter. Note that a hogged GPIO is not available
1405 to other drivers or for gpioset/gpioget.
1406 Load: dtoverlay=gpio-hog,<param>=<val>
1407 Params: gpio GPIO pin to hog (default 26)
1408 active_low If set, the hog drives the GPIO low (defaults
1409 to off - the GPIO is driven high)
1413 Info: Use GPIO pin as rc-core style infrared receiver input. The rc-core-
1414 based gpio_ir_recv driver maps received keys directly to a
1415 /dev/input/event* device, all decoding is done by the kernel - LIRC is
1416 not required! The key mapping and other decoding parameters can be
1417 configured by "ir-keytable" tool.
1418 Load: dtoverlay=gpio-ir,<param>=<val>
1419 Params: gpio_pin Input pin number. Default is 18.
1421 gpio_pull Desired pull-up/down state (off, down, up)
1424 invert "1" = invert the input (active-low signalling).
1425 "0" = non-inverted input (active-high
1426 signalling). Default is "1".
1428 rc-map-name Default rc keymap (can also be changed by
1429 ir-keytable), defaults to "rc-rc6-mce"
1433 Info: Use GPIO pin as bit-banged infrared transmitter output.
1434 This is an alternative to "pwm-ir-tx". gpio-ir-tx doesn't require
1435 a PWM so it can be used together with onboard analog audio.
1436 Load: dtoverlay=gpio-ir-tx,<param>=<val>
1437 Params: gpio_pin Output GPIO (default 18)
1439 invert "1" = invert the output (make it active-low).
1440 Default is "0" (active-high).
1444 Info: This is a generic overlay for activating GPIO keypresses using
1445 the gpio-keys library and this dtoverlay. Multiple keys can be
1446 set up using multiple calls to the overlay for configuring
1447 additional buttons or joysticks. You can see available keycodes
1448 at https://github.com/torvalds/linux/blob/v4.12/include/uapi/
1449 linux/input-event-codes.h#L64
1450 Load: dtoverlay=gpio-key,<param>=<val>
1451 Params: gpio GPIO pin to trigger on (default 3)
1452 active_low When this is 1 (active low), a falling
1453 edge generates a key down event and a
1454 rising edge generates a key up event.
1455 When this is 0 (active high), this is
1456 reversed. The default is 1 (active low)
1457 gpio_pull Desired pull-up/down state (off, down, up)
1458 Default is "up". Note that the default pin
1459 (GPIO3) has an external pullup
1460 label Set a label for the key
1461 keycode Set the key code for the button
1466 Info: This is a generic overlay for activating LEDs (or any other component)
1467 by a GPIO pin. Multiple LEDs can be set up using multiple calls to the
1468 overlay. While there are many existing methods to activate LEDs on the
1469 RPi, this method offers some advantages:
1470 1) Does not require any userspace programs.
1471 2) LEDs can be connected to the kernel's led-trigger framework,
1472 and drive the LED based on triggers such as cpu load, heartbeat,
1473 kernel panic, key input, timers and others.
1474 3) LED can be tied to the input state of another GPIO pin.
1475 4) The LED is setup early during the kernel boot process (useful
1476 for cpu/heartbeat/panic triggers).
1478 Typical electrical connection is:
1479 RPI-GPIO.19 -> LED -> 300ohm resister -> RPI-GND
1480 The GPIO pin number can be changed with the 'gpio=' parameter.
1482 To control an LED from userspace, write a 0 or 1 value:
1483 echo 1 > /sys/class/leds/myled1/brightness
1484 The 'myled1' name can be changed with the 'label=' parameter.
1486 To connect the LED to a kernel trigger from userspace:
1487 echo cpu > /sys/class/leds/myled1/trigger
1488 echo heartbeat > /sys/class/leds/myled1/trigger
1489 echo none > /sys/class/leds/myled1/trigger
1490 To connect the LED to GPIO.26 pin (physical pin 37):
1491 echo gpio > /sys/class/leds/myled1/trigger
1492 echo 26 > /sys/class/leds/myled1/gpio
1494 cat /sys/class/leds/myled1/trigger
1496 More information about the Linux kernel LED/Trigger system:
1497 https://www.kernel.org/doc/Documentation/leds/leds-class.rst
1498 https://www.kernel.org/doc/Documentation/leds/ledtrig-oneshot.rst
1499 Load: dtoverlay=gpio-led,<param>=<val>
1500 Params: gpio GPIO pin connected to the LED (default 19)
1501 label The label for this LED. It will appear under
1502 /sys/class/leds/<label> . Default 'myled1'.
1503 trigger Set the led-trigger to connect to this LED.
1504 default 'none' (LED is user-controlled).
1505 Some possible triggers:
1506 cpu - CPU load (all CPUs)
1507 cpu0 - CPU load of first CPU.
1508 mmc - disk activity (all disks)
1509 panic - turn on on kernel panic
1510 heartbeat - indicate system health
1511 gpio - connect to a GPIO input pin (note:
1512 currently the GPIO PIN can not be set
1513 using overlay parameters, must be
1514 done in userspace, see examples above.
1515 active_low Set to 1 to turn invert the LED control
1516 (writing 0 to /sys/class/leds/XXX/brightness
1517 will turn on the GPIO/LED). Default '0'.
1520 Name: gpio-no-bank0-irq
1521 Info: Use this overlay to disable GPIO interrupts for GPIOs in bank 0 (0-27),
1522 which can be useful for UIO drivers.
1523 N.B. Using this overlay will trigger a kernel WARN during booting, but
1524 this can safely be ignored - the system should work as expected.
1525 Load: dtoverlay=gpio-no-bank0-irq
1530 Info: Use this overlay to disable all GPIO interrupts, which can be useful
1531 for user-space GPIO edge detection systems.
1532 Load: dtoverlay=gpio-no-irq
1537 Info: Drives a GPIO high or low on poweroff (including halt). Using this
1538 overlay interferes with the normal power-down sequence, preventing the
1539 kernel from resetting the SoC (a necessary step in a normal power-off
1540 or reboot). This also disables the ability to trigger a boot by driving
1543 The GPIO starts in an inactive state. At poweroff time it is driven
1544 active for 100ms, then inactive for 100ms, then active again. It is
1545 safe to remove the power at any point after the initial activation of
1548 Users of this overlay are required to provide an external mechanism to
1549 switch off the power supply when signalled - failure to do so results
1550 in a kernel BUG, increased power consumption and undefined behaviour.
1551 Load: dtoverlay=gpio-poweroff,<param>=<val>
1552 Params: gpiopin GPIO for signalling (default 26)
1554 active_low Set if the power control device requires a
1555 high->low transition to trigger a power-down.
1556 Note that this will require the support of a
1557 custom dt-blob.bin to prevent a power-down
1558 during the boot process, and that a reboot
1559 will also cause the pin to go low.
1560 input Set if the gpio pin should be configured as
1562 export Set to export the configured pin to sysfs
1563 active_delay_ms Initial GPIO active period (default 100)
1564 inactive_delay_ms Subsequent GPIO inactive period (default 100)
1565 timeout_ms Specify (in ms) how long the kernel waits for
1566 power-down before issuing a WARN (default 3000).
1570 Info: Initiates a shutdown when GPIO pin changes. The given GPIO pin
1571 is configured as an input key that generates KEY_POWER events.
1573 This event is handled by systemd-logind by initiating a
1574 shutdown. Systemd versions older than 225 need an udev rule
1575 enable listening to the input device:
1577 ACTION!="REMOVE", SUBSYSTEM=="input", KERNEL=="event*", \
1578 SUBSYSTEMS=="platform", DRIVERS=="gpio-keys", \
1579 ATTRS{keys}=="116", TAG+="power-switch"
1581 Alternatively this event can be handled also on systems without
1582 systemd, just by traditional SysV init daemon. KEY_POWER event
1583 (keycode 116) needs to be mapped to KeyboardSignal on console
1584 and then kb::kbrequest inittab action which is triggered by
1585 KeyboardSignal from console can be configured to issue system
1586 shutdown. Steps for this configuration are:
1588 Add following lines to the /etc/console-setup/remap.inc file:
1590 # Key Power as special keypress
1591 keycode 116 = KeyboardSignal
1593 Then add following lines to /etc/inittab file:
1595 # Action on special keypress (Key Power)
1596 kb::kbrequest:/sbin/shutdown -t1 -a -h -P now
1598 And finally reload configuration by calling following commands:
1600 # dpkg-reconfigure console-setup
1601 # service console-setup reload
1604 This overlay only handles shutdown. After shutdown, the system
1605 can be powered up again by driving GPIO3 low. The default
1606 configuration uses GPIO3 with a pullup, so if you connect a
1607 button between GPIO3 and GND (pin 5 and 6 on the 40-pin header),
1608 you get a shutdown and power-up button. Please note that
1609 Raspberry Pi 1 Model B rev 1 uses GPIO1 instead of GPIO3.
1610 Load: dtoverlay=gpio-shutdown,<param>=<val>
1611 Params: gpio_pin GPIO pin to trigger on (default 3)
1612 For Raspberry Pi 1 Model B rev 1 set this
1613 explicitly to value 1, e.g.:
1615 dtoverlay=gpio-shutdown,gpio_pin=1
1617 active_low When this is 1 (active low), a falling
1618 edge generates a key down event and a
1619 rising edge generates a key up event.
1620 When this is 0 (active high), this is
1621 reversed. The default is 1 (active low).
1623 gpio_pull Desired pull-up/down state (off, down, up)
1626 Note that the default pin (GPIO3) has an
1627 external pullup. Same applies for GPIO1
1628 on Raspberry Pi 1 Model B rev 1.
1630 debounce Specify the debounce interval in milliseconds
1635 Info: Configures an HD44780 compatible LCD display. Uses 4 gpio pins for
1636 data, 2 gpio pins for enable and register select and 1 optional pin
1637 for enabling/disabling the backlight display.
1638 Load: dtoverlay=hd44780-lcd,<param>=<val>
1639 Params: pin_d4 GPIO pin for data pin D4 (default 6)
1641 pin_d5 GPIO pin for data pin D5 (default 13)
1643 pin_d6 GPIO pin for data pin D6 (default 19)
1645 pin_d7 GPIO pin for data pin D7 (default 26)
1647 pin_en GPIO pin for "Enable" (default 21)
1649 pin_rs GPIO pin for "Register Select" (default 20)
1651 pin_bl Optional pin for enabling/disabling the
1652 display backlight. (default disabled)
1654 display_height Height of the display in characters
1656 display_width Width of the display in characters
1659 Name: hdmi-backlight-hwhack-gpio
1660 Info: Devicetree overlay for GPIO based backlight on/off capability.
1661 Use this if you have one of those HDMI displays whose backlight cannot
1662 be controlled via DPMS over HDMI and plan to do a little soldering to
1663 use an RPi gpio pin for on/off switching. See:
1664 https://www.waveshare.com/wiki/7inch_HDMI_LCD_(C)#Backlight_Control
1665 Load: dtoverlay=hdmi-backlight-hwhack-gpio,<param>=<val>
1666 Params: gpio_pin GPIO pin used (default 17)
1667 active_low Set this to 1 if the display backlight is
1668 switched on when the wire goes low.
1669 Leave the default (value 0) if the backlight
1670 expects a high to switch it on.
1674 Info: Configures the HifiBerry Amp and Amp+ audio cards
1675 Load: dtoverlay=hifiberry-amp
1679 Name: hifiberry-amp100
1680 Info: Configures the HifiBerry AMP100 audio card
1681 Load: dtoverlay=hifiberry-amp100,<param>=<val>
1682 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1683 Digital volume control. Enable with
1684 "dtoverlay=hifiberry-amp100,24db_digital_gain"
1685 (The default behaviour is that the Digital
1686 volume control is limited to a maximum of
1687 0dB. ie. it can attenuate but not provide
1688 gain. For most users, this will be desired
1689 as it will prevent clipping. By appending
1690 the 24dB_digital_gain parameter, the Digital
1691 volume control will allow up to 24dB of
1692 gain. If this parameter is enabled, it is the
1693 responsibility of the user to ensure that
1694 the Digital volume control is set to a value
1695 that does not result in clipping/distortion!)
1696 slave Force AMP100 into slave mode, using Pi as
1697 master for bit clock and frame clock.
1698 leds_off If set to 'true' the onboard indicator LEDs
1699 are switched off at all times.
1700 auto_mute If set to 'true' the amplifier is automatically
1701 muted when the DAC is not playing.
1702 mute_ext_ctl The amplifier's HW mute control is enabled
1703 in ALSA mixer and set to <val>.
1704 Will be overwritten by ALSA user settings.
1707 Name: hifiberry-amp3
1708 Info: Configures the HifiBerry Amp3 audio card
1709 Load: dtoverlay=hifiberry-amp3
1714 Info: Configures the HifiBerry DAC audio cards
1715 Load: dtoverlay=hifiberry-dac
1719 Name: hifiberry-dacplus
1720 Info: Configures the HifiBerry DAC+ audio card
1721 Load: dtoverlay=hifiberry-dacplus,<param>=<val>
1722 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1723 Digital volume control. Enable with
1724 "dtoverlay=hifiberry-dacplus,24db_digital_gain"
1725 (The default behaviour is that the Digital
1726 volume control is limited to a maximum of
1727 0dB. ie. it can attenuate but not provide
1728 gain. For most users, this will be desired
1729 as it will prevent clipping. By appending
1730 the 24dB_digital_gain parameter, the Digital
1731 volume control will allow up to 24dB of
1732 gain. If this parameter is enabled, it is the
1733 responsibility of the user to ensure that
1734 the Digital volume control is set to a value
1735 that does not result in clipping/distortion!)
1736 slave Force DAC+ into slave mode, using Pi as
1737 master for bit clock and frame clock.
1738 leds_off If set to 'true' the onboard indicator LEDs
1739 are switched off at all times.
1742 Name: hifiberry-dacplusadc
1743 Info: Configures the HifiBerry DAC+ADC audio card
1744 Load: dtoverlay=hifiberry-dacplusadc,<param>=<val>
1745 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1746 Digital volume control. Enable with
1747 "dtoverlay=hifiberry-dacplus,24db_digital_gain"
1748 (The default behaviour is that the Digital
1749 volume control is limited to a maximum of
1750 0dB. ie. it can attenuate but not provide
1751 gain. For most users, this will be desired
1752 as it will prevent clipping. By appending
1753 the 24dB_digital_gain parameter, the Digital
1754 volume control will allow up to 24dB of
1755 gain. If this parameter is enabled, it is the
1756 responsibility of the user to ensure that
1757 the Digital volume control is set to a value
1758 that does not result in clipping/distortion!)
1759 slave Force DAC+ADC into slave mode, using Pi as
1760 master for bit clock and frame clock.
1761 leds_off If set to 'true' the onboard indicator LEDs
1762 are switched off at all times.
1765 Name: hifiberry-dacplusadcpro
1766 Info: Configures the HifiBerry DAC+ADC PRO audio card
1767 Load: dtoverlay=hifiberry-dacplusadcpro,<param>=<val>
1768 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1769 Digital volume control. Enable with
1770 "dtoverlay=hifiberry-dacplusadcpro,24db_digital_gain"
1771 (The default behaviour is that the Digital
1772 volume control is limited to a maximum of
1773 0dB. ie. it can attenuate but not provide
1774 gain. For most users, this will be desired
1775 as it will prevent clipping. By appending
1776 the 24dB_digital_gain parameter, the Digital
1777 volume control will allow up to 24dB of
1778 gain. If this parameter is enabled, it is the
1779 responsibility of the user to ensure that
1780 the Digital volume control is set to a value
1781 that does not result in clipping/distortion!)
1782 slave Force DAC+ADC Pro into slave mode, using Pi as
1783 master for bit clock and frame clock.
1784 leds_off If set to 'true' the onboard indicator LEDs
1785 are switched off at all times.
1788 Name: hifiberry-dacplusdsp
1789 Info: Configures the HifiBerry DAC+DSP audio card
1790 Load: dtoverlay=hifiberry-dacplusdsp
1794 Name: hifiberry-dacplushd
1795 Info: Configures the HifiBerry DAC+ HD audio card
1796 Load: dtoverlay=hifiberry-dacplushd
1800 Name: hifiberry-digi
1801 Info: Configures the HifiBerry Digi and Digi+ audio card
1802 Load: dtoverlay=hifiberry-digi
1806 Name: hifiberry-digi-pro
1807 Info: Configures the HifiBerry Digi+ Pro and Digi2 Pro audio card
1808 Load: dtoverlay=hifiberry-digi-pro
1813 Info: Enables "High Peripheral" mode
1814 Load: dtoverlay=highperi
1819 Info: HY28A - 2.8" TFT LCD Display Module by HAOYU Electronics
1820 Default values match Texy's display shield
1821 Load: dtoverlay=hy28a,<param>=<val>
1822 Params: speed Display SPI bus speed
1824 rotate Display rotation {0,90,180,270}
1826 fps Delay between frame updates
1828 debug Debug output level {0-7}
1830 xohms Touchpanel sensitivity (X-plate resistance)
1832 resetgpio GPIO used to reset controller
1834 ledgpio GPIO used to control backlight
1838 Info: HY28B - 2.8" TFT LCD Display Module by HAOYU Electronics
1839 Default values match Texy's display shield
1840 Load: dtoverlay=hy28b,<param>=<val>
1841 Params: speed Display SPI bus speed
1843 rotate Display rotation {0,90,180,270}
1845 fps Delay between frame updates
1847 debug Debug output level {0-7}
1849 xohms Touchpanel sensitivity (X-plate resistance)
1851 resetgpio GPIO used to reset controller
1853 ledgpio GPIO used to control backlight
1857 Info: HY28B 2017 version - 2.8" TFT LCD Display Module by HAOYU Electronics
1858 Default values match Texy's display shield
1859 Load: dtoverlay=hy28b-2017,<param>=<val>
1860 Params: speed Display SPI bus speed
1862 rotate Display rotation {0,90,180,270}
1864 fps Delay between frame updates
1866 debug Debug output level {0-7}
1868 xohms Touchpanel sensitivity (X-plate resistance)
1870 resetgpio GPIO used to reset controller
1872 ledgpio GPIO used to control backlight
1876 Info: Configures the Audiophonics I-SABRE Q2M DAC
1877 Load: dtoverlay=i-sabre-q2m
1882 Info: Fall back to the i2c_bcm2708 driver for the i2c_arm bus.
1883 Load: dtoverlay=i2c-bcm2708
1888 Info: Adds support for a number of I2C fan controllers
1889 Load: dtoverlay=i2c-fan,<param>=<val>
1890 Params: addr Sets the address for the fan controller. Note
1891 that the device must be configured to use the
1894 i2c0 Choose the I2C0 bus on GPIOs 0&1
1896 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
1898 i2c3 Choose the I2C3 bus (configure with the i2c3
1899 overlay - BCM2711 only)
1901 i2c4 Choose the I2C4 bus (configure with the i2c4
1902 overlay - BCM2711 only)
1904 i2c5 Choose the I2C5 bus (configure with the i2c5
1905 overlay - BCM2711 only)
1907 i2c6 Choose the I2C6 bus (configure with the i2c6
1908 overlay - BCM2711 only)
1910 minpwm PWM setting for the fan when the SoC is below
1911 mintemp (range 0-255. default 0)
1912 maxpwm PWM setting for the fan when the SoC is above
1913 maxtemp (range 0-255. default 255)
1914 midtemp Temperature (in millicelcius) at which the fan
1915 begins to speed up (default 50000)
1917 midtemp_hyst Temperature delta (in millicelcius) below
1918 mintemp at which the fan will drop to minrpm
1921 maxtemp Temperature (in millicelcius) at which the fan
1922 will be held at maxrpm (default 70000)
1924 maxtemp_hyst Temperature delta (in millicelcius) below
1925 maxtemp at which the fan begins to slow down
1928 emc2301 Select the Microchip EMC230x controller family
1929 - EMC2301, EMC2302, EMC2303, EMC2305.
1933 Info: Adds support for software i2c controller on gpio pins
1934 Load: dtoverlay=i2c-gpio,<param>=<val>
1935 Params: i2c_gpio_sda GPIO used for I2C data (default "23")
1937 i2c_gpio_scl GPIO used for I2C clock (default "24")
1939 i2c_gpio_delay_us Clock delay in microseconds
1940 (default "2" = ~100kHz)
1942 bus Set to a unique, non-zero value if wanting
1943 multiple i2c-gpio busses. If set, will be used
1944 as the preferred bus number (/dev/i2c-<n>). If
1945 not set, the default value is 0, but the bus
1946 number will be dynamically assigned - probably
1951 Info: Adds support for a number of I2C bus multiplexers on i2c_arm
1952 Load: dtoverlay=i2c-mux,<param>=<val>
1953 Params: pca9542 Select the NXP PCA9542 device
1955 pca9545 Select the NXP PCA9545 device
1957 pca9548 Select the NXP PCA9548 device
1959 addr Change I2C address of the device (default 0x70)
1961 i2c0 Choose the I2C0 bus on GPIOs 0&1
1963 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
1965 i2c3 Choose the I2C3 bus (configure with the i2c3
1966 overlay - BCM2711 only)
1968 i2c4 Choose the I2C3 bus (configure with the i2c3
1969 overlay - BCM2711 only)
1971 i2c5 Choose the I2C5 bus (configure with the i2c4
1972 overlay - BCM2711 only)
1974 i2c6 Choose the I2C6 bus (configure with the i2c6
1975 overlay - BCM2711 only)
1978 [ The i2c-mux-pca9548a overlay has been deleted. See i2c-mux. ]
1981 Name: i2c-pwm-pca9685a
1982 Info: Adds support for an NXP PCA9685A I2C PWM controller on i2c_arm
1983 Load: dtoverlay=i2c-pwm-pca9685a,<param>=<val>
1984 Params: addr I2C address of PCA9685A (default 0x40)
1985 i2c0 Choose the I2C0 bus on GPIOs 0&1
1986 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
1987 i2c3 Choose the I2C3 bus (configure with the i2c3
1988 overlay - BCM2711 only)
1989 i2c4 Choose the I2C3 bus (configure with the i2c3
1990 overlay - BCM2711 only)
1991 i2c5 Choose the I2C5 bus (configure with the i2c4
1992 overlay - BCM2711 only)
1993 i2c6 Choose the I2C6 bus (configure with the i2c6
1994 overlay - BCM2711 only)
1998 Info: Adds support for a number of I2C Real Time Clock devices
1999 Load: dtoverlay=i2c-rtc,<param>=<val>
2000 Params: abx80x Select one of the ABx80x family:
2001 AB0801, AB0803, AB0804, AB0805,
2002 AB1801, AB1803, AB1804, AB1805
2004 bq32000 Select the TI BQ32000 device
2006 ds1307 Select the DS1307 device
2008 ds1339 Select the DS1339 device
2010 ds1340 Select the DS1340 device
2012 ds3231 Select the DS3231 device
2014 m41t62 Select the M41T62 device
2016 mcp7940x Select the MCP7940x device
2018 mcp7941x Select the MCP7941x device
2020 pcf2127 Select the PCF2127 device
2022 pcf2129 Select the PCF2129 device
2024 pcf85063 Select the PCF85063 device
2026 pcf85063a Select the PCF85063A device
2028 pcf8523 Select the PCF8523 device
2030 pcf85363 Select the PCF85363 device
2032 pcf8563 Select the PCF8563 device
2034 rv1805 Select the Micro Crystal RV1805 device
2036 rv3028 Select the Micro Crystal RV3028 device
2038 rv3032 Select the Micro Crystal RV3032 device
2040 rv8803 Select the Micro Crystal RV8803 device
2042 sd3078 Select the ZXW Shenzhen whwave SD3078 device
2044 s35390a Select the ABLIC S35390A device
2046 i2c0 Choose the I2C0 bus on GPIOs 0&1
2048 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
2050 i2c3 Choose the I2C3 bus (configure with the i2c3
2051 overlay - BCM2711 only)
2053 i2c4 Choose the I2C3 bus (configure with the i2c3
2054 overlay - BCM2711 only)
2056 i2c5 Choose the I2C5 bus (configure with the i2c4
2057 overlay - BCM2711 only)
2059 i2c6 Choose the I2C6 bus (configure with the i2c6
2060 overlay - BCM2711 only)
2062 addr Sets the address for the RTC. Note that the
2063 device must be configured to use the specified
2066 trickle-diode-disable Do not use the internal trickle charger diode
2069 trickle-diode-type Diode type for trickle charge - "standard" or
2070 "schottky" (ABx80x and RV1805 only)
2072 trickle-resistor-ohms Resistor value for trickle charge (DS1339,
2073 ABx80x, BQ32000, RV1805, RV3028, RV3032)
2075 trickle-voltage-mv Charge pump voltage for trickle charge (RV3032)
2077 wakeup-source Specify that the RTC can be used as a wakeup
2080 backup-switchover-mode Backup power supply switch mode. Must be 0 for
2081 off or 1 for Vdd < VBackup (RV3028, RV3032)
2085 Info: Adds support for a number of I2C Real Time Clock devices
2086 using the software i2c controller
2087 Load: dtoverlay=i2c-rtc-gpio,<param>=<val>
2088 Params: abx80x Select one of the ABx80x family:
2089 AB0801, AB0803, AB0804, AB0805,
2090 AB1801, AB1803, AB1804, AB1805
2092 bq32000 Select the TI BQ32000 device
2094 ds1307 Select the DS1307 device
2096 ds1339 Select the DS1339 device
2098 ds1340 Select the DS1340 device
2100 ds3231 Select the DS3231 device
2102 m41t62 Select the M41T62 device
2104 mcp7940x Select the MCP7940x device
2106 mcp7941x Select the MCP7941x device
2108 pcf2127 Select the PCF2127 device
2110 pcf2129 Select the PCF2129 device
2112 pcf85063 Select the PCF85063 device
2114 pcf85063a Select the PCF85063A device
2116 pcf8523 Select the PCF8523 device
2118 pcf85363 Select the PCF85363 device
2120 pcf8563 Select the PCF8563 device
2122 rv1805 Select the Micro Crystal RV1805 device
2124 rv3028 Select the Micro Crystal RV3028 device
2126 rv3032 Select the Micro Crystal RV3032 device
2128 rv8803 Select the Micro Crystal RV8803 device
2130 sd3078 Select the ZXW Shenzhen whwave SD3078 device
2132 s35390a Select the ABLIC S35390A device
2134 addr Sets the address for the RTC. Note that the
2135 device must be configured to use the specified
2138 trickle-diode-disable Do not use the internal trickle charger diode
2141 trickle-diode-type Diode type for trickle charge - "standard" or
2142 "schottky" (ABx80x and RV1805 only)
2144 trickle-resistor-ohms Resistor value for trickle charge (DS1339,
2145 ABx80x, BQ32000, RV1805, RV3028, RV3032)
2147 trickle-voltage-mv Charge pump voltage for trickle charge (RV3032)
2149 wakeup-source Specify that the RTC can be used as a wakeup
2152 backup-switchover-mode Backup power supply switch mode. Must be 0 for
2153 off or 1 for Vdd < VBackup (RV3028, RV3032)
2155 i2c_gpio_sda GPIO used for I2C data (default "23")
2157 i2c_gpio_scl GPIO used for I2C clock (default "24")
2159 i2c_gpio_delay_us Clock delay in microseconds
2160 (default "2" = ~100kHz)
2164 Info: Adds support for a number of I2C barometric pressure, temperature,
2165 light level and chemical sensors on i2c_arm
2166 Load: dtoverlay=i2c-sensor,<param>=<val>
2167 Params: addr Set the address for the ADT7410, BH1750, BME280,
2168 BME680, BMP280, BMP380, CCS811, DS1621, HDC100X,
2169 JC42, LM75, MCP980x, MPU6050, MPU9250, MS5637,
2170 MS5803, MS5805, MS5837, MS8607, SHT3x or TMP102
2172 adt7410 Select the Analog Devices ADT7410 and ADT7420
2174 Valid address 0x48-0x4b, default 0x48
2176 aht10 Select the Aosong AHT10 temperature and humidity
2179 bh1750 Select the Rohm BH1750 ambient light sensor
2180 Valid addresses 0x23 or 0x5c, default 0x23
2182 bme280 Select the Bosch Sensortronic BME280
2183 Valid addresses 0x76-0x77, default 0x76
2185 bme680 Select the Bosch Sensortronic BME680
2186 Valid addresses 0x76-0x77, default 0x76
2188 bmp085 Select the Bosch Sensortronic BMP085
2190 bmp180 Select the Bosch Sensortronic BMP180
2192 bmp280 Select the Bosch Sensortronic BMP280
2193 Valid addresses 0x76-0x77, default 0x76
2195 bmp380 Select the Bosch Sensortronic BMP380
2196 Valid addresses 0x76-0x77, default 0x76
2198 bno055 Select the Bosch Sensortronic BNO055 IMU
2199 Valid address 0x28-0x29, default 0x29
2201 ccs811 Select the AMS CCS811 digital gas sensor
2202 Valid addresses 0x5a-0x5b, default 0x5b
2204 ds1621 Select the Dallas Semiconductors DS1621 temp
2205 sensor. Valid addresses 0x48-0x4f, default 0x48
2207 hdc100x Select the Texas Instruments HDC100x temp sensor
2208 Valid addresses 0x40-0x43, default 0x40
2210 htu21 Select the HTU21 temperature and humidity sensor
2212 int_pin Set the GPIO to use for interrupts (max30102,
2213 mpu6050 and mpu9250 only)
2215 jc42 Select any of the many JEDEC JC42.4-compliant
2216 temperature sensors, including:
2217 ADT7408, AT30TS00, CAT34TS02, CAT6095,
2218 MAX6604, MCP9804, MCP9805, MCP9808,
2219 MCP98242, MCP98243, MCP98244, MCP9843,
2220 SE97, SE98, STTS424(E), STTS2002, STTS3000,
2221 TSE2002, TSE2004, TS3000, and TS3001.
2222 The default address is 0x18.
2224 lm75 Select the Maxim LM75 temperature sensor
2225 Valid addresses 0x48-0x4f, default 0x4f
2227 lm75addr Deprecated - use addr parameter instead
2229 max17040 Select the Maxim Integrated MAX17040 battery
2232 max30102 Select the Maxim Integrated MAX30102 heart-rate
2233 and blood-oxygen sensor
2235 mcp980x Select the Maxim MCP980x range of temperature
2236 sensors (i.e. MCP9800, MCP9801, MCP9802 and
2237 MCP9803). N.B. For MCP9804, MCP9805 and MCP9808,
2238 use the "jc42" option.
2239 Valid addresses are 0x18-0x1f (default 0x18)
2241 mpu6050 Select the InvenSense MPU6050 IMU. Valid
2242 valid addresses are 0x68 and 0x69 (default 0x68)
2244 mpu9250 Select the InvenSense MPU9250 IMU. Valid
2245 valid addresses are 0x68 and 0x69 (default 0x68)
2247 ms5637 Select the Measurement Specialities MS5637
2248 pressure and temperature sensor.
2250 ms5803 Select the Measurement Specialities MS5803
2251 pressure and temperature sensor.
2253 ms5805 Select the Measurement Specialities MS5805
2254 pressure and temperature sensor.
2256 ms5837 Select the Measurement Specialities MS5837
2257 pressure and temperature sensor.
2259 ms8607 Select the Measurement Specialities MS8607
2260 pressure and temperature sensor.
2262 no_timeout Disable the SMBUS timeout. N.B. Only supported
2263 by some jc42 devices - using with an
2264 incompatible device can stop it from being
2267 reset_pin GPIO to be used to reset the device (bno055
2268 only, disabled by default)
2270 sht3x Select the Sensirion SHT3x temperature and
2271 humidity sensors. Valid addresses 0x44-0x45,
2274 sht4x Select the Sensirion SHT4x temperature and
2275 humidity sensors. Valid addresses 0x44-0x45,
2278 si7020 Select the Silicon Labs Si7013/20/21 humidity/
2281 sps30 Select the Sensirion SPS30 particulate matter
2282 sensor. Fixed address 0x69.
2284 sgp30 Select the Sensirion SGP30 VOC sensor.
2287 tmp102 Select the Texas Instruments TMP102 temp sensor
2288 Valid addresses 0x48-0x4b, default 0x48
2290 tsl4531 Select the AMS TSL4531 digital ambient light
2293 veml6070 Select the Vishay VEML6070 ultraviolet light
2296 i2c0 Choose the I2C0 bus on GPIOs 0&1
2298 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
2300 i2c3 Choose the I2C3 bus (configure with the i2c3
2301 overlay - BCM2711 only)
2303 i2c4 Choose the I2C3 bus (configure with the i2c3
2304 overlay - BCM2711 only)
2306 i2c5 Choose the I2C5 bus (configure with the i2c4
2307 overlay - BCM2711 only)
2309 i2c6 Choose the I2C6 bus (configure with the i2c6
2310 overlay - BCM2711 only)
2314 Info: Change i2c0 pin usage. Not all pin combinations are usable on all
2315 platforms - platforms other then Compute Modules can only use this
2316 to disable transaction combining.
2317 Do NOT use in conjunction with dtparam=i2c_vc=on. From the 5.4 kernel
2318 onwards the base DT includes the use of i2c_mux_pinctrl to expose two
2319 muxings of BSC0 - GPIOs 0&1, and whichever combination is used for the
2320 camera and display connectors. This overlay disables that mux and
2321 configures /dev/i2c0 to point at whichever set of pins is requested.
2322 dtparam=i2c_vc=on will try and enable the mux, so combining the two
2323 will cause conflicts.
2324 Load: dtoverlay=i2c0,<param>=<val>
2325 Params: pins_0_1 Use pins 0 and 1 (default)
2326 pins_28_29 Use pins 28 and 29
2327 pins_44_45 Use pins 44 and 45
2328 pins_46_47 Use pins 46 and 47
2329 combine Allow transactions to be combined (default
2334 Info: Deprecated, legacy version of i2c0.
2339 Info: Enable i2c0 (Pi 5 only)
2340 Load: dtoverlay=i2c0-pi5,<param>=<val>
2341 Params: pins_0_1 Use GPIOs 0 and 1 (default)
2342 pins_8_9 Use GPIOs 8 and 9
2343 baudrate Set the baudrate for the interface (default
2348 Info: Change i2c1 pin usage. Not all pin combinations are usable on all
2349 platforms - platforms other then Compute Modules can only use this
2350 to disable transaction combining.
2351 Load: dtoverlay=i2c1,<param>=<val>
2352 Params: pins_2_3 Use pins 2 and 3 (default)
2353 pins_44_45 Use pins 44 and 45
2354 combine Allow transactions to be combined (default
2359 Info: Deprecated, legacy version of i2c1.
2364 Info: Enable i2c1 (Pi 5 only)
2365 Load: dtoverlay=i2c1-pi5,<param>=<val>
2366 Params: pins_2_3 Use GPIOs 2 and 3 (default)
2367 pins_10_11 Use GPIOs 10 and 11
2368 baudrate Set the baudrate for the interface (default
2373 Info: Enable i2c2 (Pi 5 only)
2374 Load: dtoverlay=i2c2-pi5,<param>=<val>
2375 Params: pins_4_5 Use GPIOs 4 and 5 (default)
2376 pins_12_13 Use GPIOs 12 and 13
2377 baudrate Set the baudrate for the interface (default
2382 Info: Enable the i2c3 bus. BCM2711 only.
2383 Load: dtoverlay=i2c3,<param>
2384 Params: pins_2_3 Use GPIOs 2 and 3
2385 pins_4_5 Use GPIOs 4 and 5 (default)
2386 baudrate Set the baudrate for the interface (default
2391 Info: Enable i2c3 (Pi 5 only)
2392 Load: dtoverlay=i2c3-pi5,<param>=<val>
2393 Params: pins_6_7 Use GPIOs 6 and 7 (default)
2394 pins_14_15 Use GPIOs 14 and 15
2395 pins_22_23 Use GPIOs 22 and 23
2396 baudrate Set the baudrate for the interface (default
2401 Info: Enable the i2c4 bus. BCM2711 only.
2402 Load: dtoverlay=i2c4,<param>
2403 Params: pins_6_7 Use GPIOs 6 and 7
2404 pins_8_9 Use GPIOs 8 and 9 (default)
2405 baudrate Set the baudrate for the interface (default
2410 Info: Enable the i2c5 bus. BCM2711 only.
2411 Load: dtoverlay=i2c5,<param>
2412 Params: pins_10_11 Use GPIOs 10 and 11
2413 pins_12_13 Use GPIOs 12 and 13 (default)
2414 baudrate Set the baudrate for the interface (default
2419 Info: Enable the i2c6 bus. BCM2711 only.
2420 Load: dtoverlay=i2c6,<param>
2421 Params: pins_0_1 Use GPIOs 0 and 1
2422 pins_22_23 Use GPIOs 22 and 23 (default)
2423 baudrate Set the baudrate for the interface (default
2428 Info: Configures any passive I2S DAC soundcard.
2429 Load: dtoverlay=i2s-dac
2434 Info: move I2S function block to GPIO 28 to 31
2435 Load: dtoverlay=i2s-gpio28-31
2440 Info: Enables I2C connected Ilitek 251x multiple touch controller using
2441 GPIO 4 (pin 7 on GPIO header) for interrupt.
2442 Load: dtoverlay=ilitek251x,<param>=<val>
2443 Params: interrupt GPIO used for interrupt (default 4)
2444 sizex Touchscreen size x, horizontal resolution of
2445 touchscreen (in pixels)
2446 sizey Touchscreen size y, vertical resolution of
2447 touchscreen (in pixels)
2451 Info: Sony IMX219 camera module.
2452 Uses Unicam 1, which is the standard camera connector on most Pi
2454 Load: dtoverlay=imx219,<param>=<val>
2455 Params: rotation Mounting rotation of the camera sensor (0 or
2457 orientation Sensor orientation (0 = front, 1 = rear,
2458 2 = external, default external)
2459 media-controller Configure use of Media Controller API for
2460 configuring the sensor (default on)
2461 cam0 Adopt the default configuration for CAM0 on a
2462 Compute Module (CSI0, i2c_vc, and cam0_reg).
2463 vcm Configure a VCM focus drive on the sensor.
2467 Info: Sony IMX258 camera module.
2468 Uses Unicam 1, which is the standard camera connector on most Pi
2470 Load: dtoverlay=imx258,<param>=<val>
2471 Params: rotation Mounting rotation of the camera sensor (0 or
2473 orientation Sensor orientation (0 = front, 1 = rear,
2474 2 = external, default external)
2475 media-controller Configure use of Media Controller API for
2476 configuring the sensor (default on)
2477 cam0 Adopt the default configuration for CAM0 on a
2478 Compute Module (CSI0, i2c_vc, and cam0_reg).
2479 vcm Configure a VCM focus drive on the sensor.
2480 4lane Enable 4 CSI2 lanes. This requires a Compute
2481 Module (1, 3, or 4).
2485 Info: Sony IMX290 camera module.
2486 Uses Unicam 1, which is the standard camera connector on most Pi
2488 Load: dtoverlay=imx290,<param>
2489 Params: 4lane Enable 4 CSI2 lanes. This requires a Compute
2490 Module (1, 3, or 4).
2491 clock-frequency Sets the clock frequency to match that used on
2493 Modules from Vision Components use 37.125MHz
2494 (the default), whilst those from Innomaker use
2496 mono Denote that the module is a mono sensor.
2497 orientation Sensor orientation (0 = front, 1 = rear,
2498 2 = external, default external)
2499 rotation Mounting rotation of the camera sensor (0 or
2501 media-controller Configure use of Media Controller API for
2502 configuring the sensor (default on)
2503 cam0 Adopt the default configuration for CAM0 on a
2504 Compute Module (CSI0, i2c_vc, and cam0_reg).
2508 Info: Sony IMX296 camera module.
2509 Uses Unicam 1, which is the standard camera connector on most Pi
2511 Load: dtoverlay=imx296,<param>=<val>
2512 Params: rotation Mounting rotation of the camera sensor (0 or
2514 orientation Sensor orientation (0 = front, 1 = rear,
2515 2 = external, default external)
2516 media-controller Configure use of Media Controller API for
2517 configuring the sensor (default on)
2518 cam0 Adopt the default configuration for CAM0 on a
2519 Compute Module (CSI0, i2c_vc, and cam0_reg).
2520 clock-frequency Sets the clock frequency to match that used on
2521 the board, which should be one of 54000000
2522 (the default), 37125000 or 74250000.
2526 Info: Sony IMX327 camera module.
2527 Uses Unicam 1, which is the standard camera connector on most Pi
2529 Load: dtoverlay=imx327,<param>
2530 Params: 4lane Enable 4 CSI2 lanes. This requires a Compute
2531 Module (1, 3, or 4).
2532 clock-frequency Sets the clock frequency to match that used on
2534 Modules from Vision Components use 37.125MHz
2535 (the default), whilst those from Innomaker use
2537 mono Denote that the module is a mono sensor.
2538 orientation Sensor orientation (0 = front, 1 = rear,
2539 2 = external, default external)
2540 rotation Mounting rotation of the camera sensor (0 or
2542 media-controller Configure use of Media Controller API for
2543 configuring the sensor (default on)
2544 cam0 Adopt the default configuration for CAM0 on a
2545 Compute Module (CSI0, i2c_vc, and cam0_reg).
2549 Info: Sony IMX378 camera module.
2550 Uses Unicam 1, which is the standard camera connector on most Pi
2552 Load: dtoverlay=imx378,<param>=<val>
2553 Params: rotation Mounting rotation of the camera sensor (0 or
2555 orientation Sensor orientation (0 = front, 1 = rear,
2556 2 = external, default external)
2557 media-controller Configure use of Media Controller API for
2558 configuring the sensor (default on)
2559 cam0 Adopt the default configuration for CAM0 on a
2560 Compute Module (CSI0, i2c_vc, and cam0_reg).
2564 Info: Sony IMX462 camera module.
2565 Uses Unicam 1, which is the standard camera connector on most Pi
2567 Load: dtoverlay=imx462,<param>
2568 Params: 4lane Enable 4 CSI2 lanes. This requires a Compute
2569 Module (1, 3, or 4).
2570 clock-frequency Sets the clock frequency to match that used on
2572 Modules from Vision Components use 37.125MHz
2573 (the default), whilst those from Innomaker use
2575 mono Denote that the module is a mono sensor.
2576 orientation Sensor orientation (0 = front, 1 = rear,
2577 2 = external, default external)
2578 rotation Mounting rotation of the camera sensor (0 or
2580 media-controller Configure use of Media Controller API for
2581 configuring the sensor (default on)
2582 cam0 Adopt the default configuration for CAM0 on a
2583 Compute Module (CSI0, i2c_vc, and cam0_reg).
2587 Info: Sony IMX477 camera module.
2588 Uses Unicam 1, which is the standard camera connector on most Pi
2590 Load: dtoverlay=imx477,<param>=<val>
2591 Params: rotation Mounting rotation of the camera sensor (0 or
2593 orientation Sensor orientation (0 = front, 1 = rear,
2594 2 = external, default external)
2595 media-controller Configure use of Media Controller API for
2596 configuring the sensor (default on)
2597 cam0 Adopt the default configuration for CAM0 on a
2598 Compute Module (CSI0, i2c_vc, and cam0_reg).
2602 Info: Sony IMX519 camera module.
2603 Uses Unicam 1, which is the standard camera connector on most Pi
2605 Load: dtoverlay=imx519,<param>=<val>
2606 Params: rotation Mounting rotation of the camera sensor (0 or
2608 orientation Sensor orientation (0 = front, 1 = rear,
2609 2 = external, default external)
2610 media-controller Configure use of Media Controller API for
2611 configuring the sensor (default on)
2612 cam0 Adopt the default configuration for CAM0 on a
2613 Compute Module (CSI0, i2c_vc, and cam0_reg).
2614 vcm Select lens driver state. Default is enabled,
2615 but vcm=off will disable.
2619 Info: Sony IMX708 camera module.
2620 Uses Unicam 1, which is the standard camera connector on most Pi
2622 Load: dtoverlay=imx708,<param>=<val>
2623 Params: rotation Mounting rotation of the camera sensor (0 or
2625 orientation Sensor orientation (0 = front, 1 = rear,
2626 2 = external, default external)
2627 vcm Select lens driver state. Default is enabled,
2628 but vcm=off will disable.
2629 media-controller Configure use of Media Controller API for
2630 configuring the sensor (default on)
2631 cam0 Adopt the default configuration for CAM0 on a
2632 Compute Module (CSI0, i2c_vc, and cam0_reg).
2633 link-frequency Allowable link frequency values to use in Hz:
2634 450000000 (default), 447000000, 453000000.
2638 Info: Configures the IQaudio Codec audio card
2639 Load: dtoverlay=iqaudio-codec
2644 Info: Configures the IQaudio DAC audio card
2645 Load: dtoverlay=iqaudio-dac,<param>
2646 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2647 Digital volume control. Enable with
2648 "dtoverlay=iqaudio-dac,24db_digital_gain"
2649 (The default behaviour is that the Digital
2650 volume control is limited to a maximum of
2651 0dB. ie. it can attenuate but not provide
2652 gain. For most users, this will be desired
2653 as it will prevent clipping. By appending
2654 the 24db_digital_gain parameter, the Digital
2655 volume control will allow up to 24dB of
2656 gain. If this parameter is enabled, it is the
2657 responsibility of the user to ensure that
2658 the Digital volume control is set to a value
2659 that does not result in clipping/distortion!)
2662 Name: iqaudio-dacplus
2663 Info: Configures the IQaudio DAC+ audio card
2664 Load: dtoverlay=iqaudio-dacplus,<param>=<val>
2665 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2666 Digital volume control. Enable with
2667 "dtoverlay=iqaudio-dacplus,24db_digital_gain"
2668 (The default behaviour is that the Digital
2669 volume control is limited to a maximum of
2670 0dB. ie. it can attenuate but not provide
2671 gain. For most users, this will be desired
2672 as it will prevent clipping. By appending
2673 the 24db_digital_gain parameter, the Digital
2674 volume control will allow up to 24dB of
2675 gain. If this parameter is enabled, it is the
2676 responsibility of the user to ensure that
2677 the Digital volume control is set to a value
2678 that does not result in clipping/distortion!)
2679 auto_mute_amp If specified, unmute/mute the IQaudIO amp when
2680 starting/stopping audio playback.
2681 unmute_amp If specified, unmute the IQaudIO amp once when
2682 the DAC driver module loads.
2685 Name: iqaudio-digi-wm8804-audio
2686 Info: Configures the IQAudIO Digi WM8804 audio card
2687 Load: dtoverlay=iqaudio-digi-wm8804-audio,<param>=<val>
2688 Params: card_name Override the default, "IQAudIODigi", card name.
2689 dai_name Override the default, "IQAudIO Digi", dai name.
2690 dai_stream_name Override the default, "IQAudIO Digi HiFi",
2695 Info: Enables I2C connected Azoteq IQS550 trackpad/touchscreen controller
2696 using GPIO 4 (pin 7 on GPIO header) for interrupt.
2697 Load: dtoverlay=iqs550,<param>=<val>
2698 Params: interrupt GPIO used for interrupt (default 4)
2699 reset GPIO used for reset (optional)
2700 sizex Touchscreen size x (default 800)
2701 sizey Touchscreen size y (default 480)
2702 invx Touchscreen inverted x axis
2703 invy Touchscreen inverted y axis
2704 swapxy Touchscreen swapped x y axis
2708 Info: Infineon irs1125 TOF camera module.
2709 Uses Unicam 1, which is the standard camera connector on most Pi
2711 Load: dtoverlay=irs1125,<param>=<val>
2712 Params: media-controller Configure use of Media Controller API for
2713 configuring the sensor (default off)
2714 cam0 Adopt the default configuration for CAM0 on a
2715 Compute Module (CSI0, i2c_vc, and cam0_reg).
2719 Info: Adds support for JEDEC-compliant SPI NOR flash devices. (Note: The
2720 "jedec,spi-nor" kernel driver was formerly known as "m25p80".)
2721 Load: dtoverlay=jedec-spi-nor,<param>=<val>
2722 Params: spi<n>-<m> Enable flash device on SPI<n>, CS#<m>
2723 fastr Add fast read capability to the flash device
2724 speed Maximum SPI frequency (Hz)
2725 flash-spi<n>-<m> Same as spi<n>-<m> (deprecated)
2726 flash-fastr-spi<n>-<m> Same as spi<n>->m>,fastr (deprecated)
2730 Info: Simultaneous usage of an justboom-dac and justboom-digi based
2732 Load: dtoverlay=justboom-both,<param>=<val>
2733 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2734 Digital volume control. Enable with
2735 "dtoverlay=justboom-dac,24db_digital_gain"
2736 (The default behaviour is that the Digital
2737 volume control is limited to a maximum of
2738 0dB. ie. it can attenuate but not provide
2739 gain. For most users, this will be desired
2740 as it will prevent clipping. By appending
2741 the 24dB_digital_gain parameter, the Digital
2742 volume control will allow up to 24dB of
2743 gain. If this parameter is enabled, it is the
2744 responsibility of the user to ensure that
2745 the Digital volume control is set to a value
2746 that does not result in clipping/distortion!)
2750 Info: Configures the JustBoom DAC HAT, Amp HAT, DAC Zero and Amp Zero audio
2752 Load: dtoverlay=justboom-dac,<param>=<val>
2753 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2754 Digital volume control. Enable with
2755 "dtoverlay=justboom-dac,24db_digital_gain"
2756 (The default behaviour is that the Digital
2757 volume control is limited to a maximum of
2758 0dB. ie. it can attenuate but not provide
2759 gain. For most users, this will be desired
2760 as it will prevent clipping. By appending
2761 the 24dB_digital_gain parameter, the Digital
2762 volume control will allow up to 24dB of
2763 gain. If this parameter is enabled, it is the
2764 responsibility of the user to ensure that
2765 the Digital volume control is set to a value
2766 that does not result in clipping/distortion!)
2770 Info: Configures the JustBoom Digi HAT and Digi Zero audio cards
2771 Load: dtoverlay=justboom-digi
2776 Info: This overlay has been deprecated and removed - see gpio-ir
2781 Info: Adds support for the ltc294x family of battery gauges
2782 Load: dtoverlay=ltc294x,<param>=<val>
2783 Params: ltc2941 Select the ltc2941 device
2785 ltc2942 Select the ltc2942 device
2787 ltc2943 Select the ltc2943 device
2789 ltc2944 Select the ltc2944 device
2791 resistor-sense The sense resistor value in milli-ohms.
2792 Can be a 32-bit negative value when the battery
2793 has been connected to the wrong end of the
2796 prescaler-exponent Range and accuracy of the gauge. The value is
2797 programmed into the chip only if it differs
2798 from the current setting.
2800 - Default value is 128
2801 - the exponent is in the range 0-7 (default 7)
2802 See the datasheet for more information.
2806 Info: Configures the Maxim MAX98357A I2S DAC
2807 Load: dtoverlay=max98357a,<param>=<val>
2808 Params: no-sdmode Driver does not manage the state of the DAC's
2809 SD_MODE pin (i.e. chip is always on).
2810 sdmode-pin integer, GPIO pin connected to the SD_MODE input
2811 of the DAC (default GPIO4 if parameter omitted).
2815 Info: Configure a MAX6675, MAX31855 or MAX31856 thermocouple as an IIO device.
2817 For devices on spi1 or spi2, the interfaces should be enabled
2818 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2819 The overlay expects to disable the relevant spidev node, so also using
2820 e.g. cs0_spidev=off is unnecessary.
2823 MAX31855 on /dev/spidev0.0
2824 dtoverlay=maxtherm,spi0-0,max31855
2825 MAX31856 using a type J thermocouple on /dev/spidev2.1
2827 dtoverlay=maxtherm,spi2-1,max31856,type_j
2829 Load: dtoverlay=maxtherm,<param>=<val>
2830 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2832 max6675 Enable support for the MAX6675 (default)
2833 max31855 Enable support for the MAX31855
2834 max31855e Enable support for the MAX31855E
2835 max31855j Enable support for the MAX31855J
2836 max31855k Enable support for the MAX31855K
2837 max31855n Enable support for the MAX31855N
2838 max31855r Enable support for the MAX31855R
2839 max31855s Enable support for the MAX31855S
2840 max31855t Enable support for the MAX31855T
2841 max31856 Enable support for the MAX31856 (with type K)
2842 type_b Select a type B sensor for max31856
2843 type_e Select a type E sensor for max31856
2844 type_j Select a type J sensor for max31856
2845 type_k Select a type K sensor for max31856
2846 type_n Select a type N sensor for max31856
2847 type_r Select a type R sensor for max31856
2848 type_s Select a type S sensor for max31856
2849 type_t Select a type T sensor for max31856
2853 Info: Configures the mbed AudioCODEC (TLV320AIC23B)
2854 Load: dtoverlay=mbed-dac
2859 Info: Configures the MCP23017 I2C GPIO expander
2860 Load: dtoverlay=mcp23017,<param>=<val>
2861 Params: gpiopin Gpio pin connected to the INTA output of the
2862 MCP23017 (default: 4)
2864 addr I2C address of the MCP23017 (default: 0x20)
2866 mcp23008 Configure an MCP23008 instead.
2867 noints Disable the interrupt GPIO line.
2868 i2c0 Choose the I2C0 bus on GPIOs 0&1
2869 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
2870 i2c3 Choose the I2C3 bus (configure with the i2c3
2871 overlay - BCM2711 only)
2872 i2c4 Choose the I2C4 bus (configure with the i2c4
2873 overlay - BCM2711 only)
2874 i2c5 Choose the I2C5 bus (configure with the i2c5
2875 overlay - BCM2711 only)
2876 i2c6 Choose the I2C6 bus (configure with the i2c6
2877 overlay - BCM2711 only)
2881 Info: Configures the MCP23S08/17 SPI GPIO expanders.
2882 If devices are present on SPI1 or SPI2, those interfaces must be enabled
2883 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2884 If interrupts are enabled for a device on a given CS# on a SPI bus, that
2885 device must be the only one present on that SPI bus/CS#.
2886 Load: dtoverlay=mcp23s17,<param>=<val>
2887 Params: s08-spi<n>-<m>-present 4-bit integer, bitmap indicating MCP23S08
2888 devices present on SPI<n>, CS#<m>
2890 s17-spi<n>-<m>-present 8-bit integer, bitmap indicating MCP23S17
2891 devices present on SPI<n>, CS#<m>
2893 s08-spi<n>-<m>-int-gpio integer, enables interrupts on a single
2894 MCP23S08 device on SPI<n>, CS#<m>, specifies
2895 the GPIO pin to which INT output of MCP23S08
2898 s17-spi<n>-<m>-int-gpio integer, enables mirrored interrupts on a
2899 single MCP23S17 device on SPI<n>, CS#<m>,
2900 specifies the GPIO pin to which either INTA
2901 or INTB output of MCP23S17 is connected.
2905 Info: Configures the MCP2515 CAN controller on spi0/1/2
2906 For devices on spi1 or spi2, the interfaces should be enabled
2907 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2908 Load: dtoverlay=mcp2515,<param>=<val>
2909 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2912 oscillator Clock frequency for the CAN controller (Hz)
2914 speed Maximum SPI frequence (Hz)
2916 interrupt GPIO for interrupt signal
2920 Info: Configures the MCP2515 CAN controller on spi0.0
2921 Load: dtoverlay=mcp2515-can0,<param>=<val>
2922 Params: oscillator Clock frequency for the CAN controller (Hz)
2924 spimaxfrequency Maximum SPI frequence (Hz)
2926 interrupt GPIO for interrupt signal
2930 Info: Configures the MCP2515 CAN controller on spi0.1
2931 Load: dtoverlay=mcp2515-can1,<param>=<val>
2932 Params: oscillator Clock frequency for the CAN controller (Hz)
2934 spimaxfrequency Maximum SPI frequence (Hz)
2936 interrupt GPIO for interrupt signal
2940 Info: Configures the MCP251XFD CAN controller family
2941 For devices on spi1 or spi2, the interfaces should be enabled
2942 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2943 Load: dtoverlay=mcp251xfd,<param>=<val>
2944 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2947 oscillator Clock frequency for the CAN controller (Hz)
2949 speed Maximum SPI frequence (Hz)
2951 interrupt GPIO for interrupt signal
2953 rx_interrupt GPIO for RX interrupt signal (nINT1) (optional)
2955 xceiver_enable GPIO for CAN transceiver enable (optional)
2957 xceiver_active_high specifiy if CAN transceiver enable pin is
2958 active high (optional, default: active low)
2962 Info: Configures MCP3008 A/D converters
2963 For devices on spi1 or spi2, the interfaces should be enabled
2964 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2965 Load: dtoverlay=mcp3008,<param>[=<val>]
2966 Params: spi<n>-<m>-present boolean, configure device at spi<n>, cs<m>
2967 spi<n>-<m>-speed integer, set the spi bus speed for this device
2971 Info: Configures MCP3202 A/D converters
2972 For devices on spi1 or spi2, the interfaces should be enabled
2973 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2974 Load: dtoverlay=mcp3202,<param>[=<val>]
2975 Params: spi<n>-<m>-present boolean, configure device at spi<n>, cs<m>
2976 spi<n>-<m>-speed integer, set the spi bus speed for this device
2980 Info: Overlay for activation of Microchip MCP3421-3428 ADCs over I2C
2981 Load: dtoverlay=mcp342x,<param>=<val>
2982 Params: addr I2C bus address of device, for devices with
2983 addresses that are configurable, e.g. by
2984 hardware links (default=0x68)
2985 mcp3421 The device is an MCP3421
2986 mcp3422 The device is an MCP3422
2987 mcp3423 The device is an MCP3423
2988 mcp3424 The device is an MCP3424
2989 mcp3425 The device is an MCP3425
2990 mcp3426 The device is an MCP3426
2991 mcp3427 The device is an MCP3427
2992 mcp3428 The device is an MCP3428
2996 Info: Media Center HAT - 2.83" Touch Display + extras by Pi Supply
2997 Load: dtoverlay=media-center,<param>=<val>
2998 Params: speed Display SPI bus speed
2999 rotate Display rotation {0,90,180,270}
3000 fps Delay between frame updates
3001 xohms Touchpanel sensitivity (X-plate resistance)
3002 swapxy Swap x and y axis
3003 backlight Change backlight GPIO pin {e.g. 12, 18}
3004 debug "on" = enable additional debug messages
3009 Info: Configures the merus-amp audio card
3010 Load: dtoverlay=merus-amp
3015 Info: Configures UART0 (ttyAMA0) so that a requested 38.4kbaud actually gets
3016 31.25kbaud, the frequency required for MIDI
3017 Load: dtoverlay=midi-uart0
3021 Name: midi-uart0-pi5
3022 Info: See midi-uart0 (this is the Pi 5 version)
3026 Info: Configures UART1 (ttyS0) so that a requested 38.4kbaud actually gets
3027 31.25kbaud, the frequency required for MIDI
3028 Load: dtoverlay=midi-uart1
3032 Name: midi-uart1-pi5
3033 Info: See midi-uart1 (this is the Pi 5 version)
3037 Info: Configures UART2 (ttyAMA2) so that a requested 38.4kbaud actually gets
3038 31.25kbaud, the frequency required for MIDI
3039 Load: dtoverlay=midi-uart2
3043 Name: midi-uart2-pi5
3044 Info: See midi-uart2 (this is the Pi 5 version)
3048 Info: Configures UART3 (ttyAMA3) so that a requested 38.4kbaud actually gets
3049 31.25kbaud, the frequency required for MIDI
3050 Load: dtoverlay=midi-uart3
3054 Name: midi-uart3-pi5
3055 Info: See midi-uart3 (this is the Pi 5 version)
3059 Info: Configures UART4 (ttyAMA4) so that a requested 38.4kbaud actually gets
3060 31.25kbaud, the frequency required for MIDI
3061 Load: dtoverlay=midi-uart4
3065 Name: midi-uart4-pi5
3066 Info: See midi-uart4 (this is the Pi 5 version)
3070 Info: Configures UART5 (ttyAMA5) so that a requested 38.4kbaud actually gets
3071 31.25kbaud, the frequency required for MIDI
3072 Load: dtoverlay=midi-uart5
3077 Info: Overlay for AdaFruit Mini Pi 1.3" TFT via SPI using fbtft driver.
3078 Load: dtoverlay=minipitft13,<param>=<val>
3079 Params: speed SPI bus speed (default 32000000)
3080 rotate Display rotation (0, 90, 180 or 270; default 0)
3081 width Display width (default 240)
3082 height Display height (default 240)
3083 fps Delay between frame updates (default 25)
3084 debug Debug output level (0-7; default 0)
3088 Info: Switch the onboard Bluetooth function of a BT-equipped Raspberry Pi
3089 to use the mini-UART (ttyS0) and restore UART0/ttyAMA0 over GPIOs 14 &
3090 15. Note that this option uses a lower baudrate, and should only be used
3091 with low-bandwidth peripherals.
3092 Load: dtoverlay=miniuart-bt,<param>=<val>
3093 Params: krnbt Set to "off" to disable autoprobing of Bluetooth
3094 driver without need of hciattach/btattach
3098 Info: Overlay for SPI-connected MIPI DBI displays using the panel-mipi-dbi
3099 driver. The driver will load a file /lib/firmware/panel.bin containing
3100 the initialisation commands.
3103 dtoverlay=mipi-dbi-spi,spi0-0,speed=70000000
3104 dtparam=width=320,height=240
3105 dtparam=reset-gpio=23,dc-gpio=24
3106 dtparam=backlight-gpio=18
3108 Compared to fbtft panel-mipi-dbi runs pixel data at spi-max-frequency
3109 and init commands at 10MHz. This makes it possible to push the envelope
3110 without messing up the controller configuration due to command
3111 transmission errors.
3113 For devices on spi1 or spi2, the interfaces should be enabled
3114 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
3116 See https://github.com/notro/panel-mipi-dbi/wiki for more info.
3118 Load: dtoverlay=mipi-dbi-spi,<param>=<val>
3120 compatible Set the compatible string to load a different
3121 firmware file. Both the panel compatible value
3122 used to load the firmware file and the value
3123 used to load the driver has to be set having a
3124 NUL (\0) separator between them.
3126 dtparam=compatible=mypanel\0panel-mipi-dbi-spi
3127 spi<n>-<m> Configure device at spi<n>, cs<m>
3129 speed SPI bus speed in Hz (default 32000000)
3130 cpha Shifted SPI clock phase (CPHA) mode
3131 cpol Inverse SPI clock polarity (CPOL) mode
3132 write-only Controller is not readable
3133 (ie. MISO is not wired up).
3135 width Panel width in pixels (required)
3136 height Panel height in pixels (required)
3137 width-mm Panel width in mm
3138 height-mm Panel height in mm
3139 x-offset Panel x-offset in controller RAM
3140 y-offset Panel y-offset in controller RAM
3142 clock-frequency Panel clock frequency in Hz
3143 (optional, just informational).
3145 reset-gpio GPIO pin to be used for RESET
3146 dc-gpio GPIO pin to be used for D/C
3148 backlight-gpio GPIO pin to be used for backlight control
3150 backlight-pwm PWM channel to be used for backlight control
3151 (default of none). NB Disables audio headphone
3152 output as that also uses PWM.
3153 backlight-pwm-chan Choose channel on &pwm node for backlight
3154 control (default 0).
3155 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
3156 pwm-2chan for valid options (default 18).
3157 backlight-pwm-func Pin function of GPIO used for the PWM backlight.
3158 See pwm-2chan for valid options (default 2).
3159 backlight-def-brightness
3160 Set the default brightness. Normal range 1-16.
3165 Info: Overlay for i2c connected mlx90640 thermal camera
3166 Load: dtoverlay=mlx90640
3171 Info: Selects the bcm2835-mmc SD/MMC driver, optionally with overclock
3172 Load: dtoverlay=mmc,<param>=<val>
3173 Params: overclock_50 Clock (in MHz) to use when the MMC framework
3178 Info: This overlay has been deprecated - use "dtoverlay=i2c-sensor,mpu6050"
3179 instead. Note that "int_pin" is the new name for the "interrupt"
3185 Info: MZ61581 display by Tontec
3186 Load: dtoverlay=mz61581,<param>=<val>
3187 Params: speed Display SPI bus speed
3189 rotate Display rotation {0,90,180,270}
3191 fps Delay between frame updates
3193 txbuflen Transmit buffer length (default 32768)
3195 debug Debug output level {0-7}
3197 xohms Touchpanel sensitivity (X-plate resistance)
3201 Info: Omnivision OV2311 camera module.
3202 Uses Unicam 1, which is the standard camera connector on most Pi
3204 Load: dtoverlay=ov2311,<param>=<val>
3205 Params: rotation Mounting rotation of the camera sensor (0 or
3207 orientation Sensor orientation (0 = front, 1 = rear,
3208 2 = external, default external)
3209 media-controller Configure use of Media Controller API for
3210 configuring the sensor (default on)
3211 cam0 Adopt the default configuration for CAM0 on a
3212 Compute Module (CSI0, i2c_vc, and cam0_reg).
3216 Info: Omnivision OV5647 camera module.
3217 Uses Unicam 1, which is the standard camera connector on most Pi
3219 Load: dtoverlay=ov5647,<param>=<val>
3220 Params: rotation Mounting rotation of the camera sensor (0 or
3222 orientation Sensor orientation (0 = front, 1 = rear,
3223 2 = external, default external)
3224 media-controller Configure use of Media Controller API for
3225 configuring the sensor (default on)
3226 cam0 Adopt the default configuration for CAM0 on a
3227 Compute Module (CSI0, i2c_vc, and cam0_reg).
3228 vcm Configure a VCM focus drive on the sensor.
3232 Info: Arducam OV64A40 camera module.
3233 Uses Unicam 1, which is the standard camera connector on most Pi
3235 Load: dtoverlay=ov64a40,<param>=<val>
3236 Params: rotation Mounting rotation of the camera sensor (0 or
3238 orientation Sensor orientation (0 = front, 1 = rear,
3239 2 = external, default external)
3240 media-controller Configure use of Media Controller API for
3241 configuring the sensor (default on)
3242 cam0 Adopt the default configuration for CAM0 on a
3243 Compute Module (CSI0, i2c_vc, and cam0_reg).
3244 vcm Select lens driver state. Default is enabled,
3245 but vcm=off will disable.
3246 link-frequency Allowable link frequency values to use in Hz:
3247 456000000 (default), 360000000
3251 Info: Omnivision OV7251 camera module.
3252 Uses Unicam 1, which is the standard camera connector on most Pi
3254 Load: dtoverlay=ov7251,<param>=<val>
3255 Params: rotation Mounting rotation of the camera sensor (0 or
3257 orientation Sensor orientation (0 = front, 1 = rear,
3258 2 = external, default external)
3259 media-controller Configure use of Media Controller API for
3260 configuring the sensor (default off)
3261 cam0 Adopt the default configuration for CAM0 on a
3262 Compute Module (CSI0, i2c_vc, and cam0_reg).
3266 Info: Omnivision OV9281 camera module.
3267 Uses Unicam 1, which is the standard camera connector on most Pi
3269 Load: dtoverlay=ov9281,<param>=<val>
3270 Params: rotation Mounting rotation of the camera sensor (0 or
3272 orientation Sensor orientation (0 = front, 1 = rear,
3273 2 = external, default external)
3274 media-controller Configure use of Media Controller API for
3275 configuring the sensor (default on)
3276 cam0 Adopt the default configuration for CAM0 on a
3277 Compute Module (CSI0, i2c_vc, and cam0_reg).
3281 Info: PaPiRus ePaper Screen by Pi Supply (both HAT and pHAT)
3282 Load: dtoverlay=papirus,<param>=<val>
3283 Params: panel Display panel (required):
3288 speed Display SPI bus speed
3292 Info: TI PCA953x family of I2C GPIO expanders. Default is for NXP PCA9534.
3293 Load: dtoverlay=pca953x,<param>=<val>
3294 Params: addr I2C address of expander. Default 0x20.
3295 pca6416 Select the NXP PCA6416 (16 bit)
3296 pca9505 Select the NXP PCA9505 (40 bit)
3297 pca9535 Select the NXP PCA9535 (16 bit)
3298 pca9536 Select the NXP PCA9536 or TI PCA9536 (4 bit)
3299 pca9537 Select the NXP PCA9537 (4 bit)
3300 pca9538 Select the NXP PCA9538 (8 bit)
3301 pca9539 Select the NXP PCA9539 (16 bit)
3302 pca9554 Select the NXP PCA9554 (8 bit)
3303 pca9555 Select the NXP PCA9555 (16 bit)
3304 pca9556 Select the NXP PCA9556 (8 bit)
3305 pca9557 Select the NXP PCA9557 (8 bit)
3306 pca9574 Select the NXP PCA9574 (8 bit)
3307 pca9575 Select the NXP PCA9575 (16 bit)
3308 pca9698 Select the NXP PCA9698 (40 bit)
3309 pcal6416 Select the NXP PCAL6416 (16 bit)
3310 pcal6524 Select the NXP PCAL6524 (24 bit)
3311 pcal9555a Select the NXP PCAL9555A (16 bit)
3312 max7310 Select the Maxim MAX7310 (8 bit)
3313 max7312 Select the Maxim MAX7312 (16 bit)
3314 max7313 Select the Maxim MAX7313 (16 bit)
3315 max7315 Select the Maxim MAX7315 (8 bit)
3316 pca6107 Select the TI PCA6107 (8 bit)
3317 tca6408 Select the TI TCA6408 (8 bit)
3318 tca6416 Select the TI TCA6416 (16 bit)
3319 tca6424 Select the TI TCA6424 (24 bit)
3320 tca9539 Select the TI TCA9539 (16 bit)
3321 tca9554 Select the TI TCA9554 (8 bit)
3322 cat9554 Select the Onnn CAT9554 (8 bit)
3323 pca9654 Select the Onnn PCA9654 (8 bit)
3324 xra1202 Select the Exar XRA1202 (8 bit)
3328 Info: NXP PCF857x family of I2C GPIO expanders.
3329 Load: dtoverlay=pcf857x,<param>=<val>
3330 Params: addr I2C address of expander. Default
3331 depends on model selected.
3332 pcf8574 Select the NXP PCF8574 (8 bit)
3333 pcf8574a Select the NXP PCF8574A (8 bit)
3334 pcf8575 Select the NXP PCF8575 (16 bit)
3335 pca8574 Select the NXP PCA8574 (8 bit)
3338 Name: pcie-32bit-dma
3339 Info: Force PCIe config to support 32bit DMA addresses at the expense of
3340 having to bounce buffers.
3341 Load: dtoverlay=pcie-32bit-dma
3345 [ The pcf2127-rtc overlay has been deleted. See i2c-rtc. ]
3348 [ The pcf8523-rtc overlay has been deleted. See i2c-rtc. ]
3351 [ The pcf8563-rtc overlay has been deleted. See i2c-rtc. ]
3355 Info: This overlay has been renamed act-led, keeping pi3-act-led as an alias
3356 for backwards compatibility.
3360 Name: pi3-disable-bt
3361 Info: This overlay has been renamed disable-bt, keeping pi3-disable-bt as an
3362 alias for backwards compatibility.
3366 Name: pi3-disable-wifi
3367 Info: This overlay has been renamed disable-wifi, keeping pi3-disable-wifi as
3368 an alias for backwards compatibility.
3372 Name: pi3-miniuart-bt
3373 Info: This overlay has been renamed miniuart-bt, keeping pi3-miniuart-bt as
3374 an alias for backwards compatibility.
3379 Info: Configures the pibell audio card.
3380 Load: dtoverlay=pibell,<param>=<val>
3381 Params: alsaname Set the name as it appears in ALSA (default
3386 Info: Configures the PiFace Digital mcp23s17 GPIO port expander.
3387 Load: dtoverlay=pifacedigital,<param>=<val>
3388 Params: spi-present-mask 8-bit integer, bitmap indicating MCP23S17 SPI0
3389 CS0 address. PiFace Digital supports addresses
3390 0-3, which can be configured with JP1 and JP2.
3394 Info: Configures the PiFi 40W stereo amplifier
3395 Load: dtoverlay=pifi-40
3400 Info: Configures the PiFi DAC HD
3401 Load: dtoverlay=pifi-dac-hd
3406 Info: Configures the PiFi DAC Zero
3407 Load: dtoverlay=pifi-dac-zero
3412 Info: Configures the PiFi Mini stereo amplifier
3413 Load: dtoverlay=pifi-mini-210
3418 Info: Configures the PiGlow by pimoroni.com
3419 Load: dtoverlay=piglow
3424 Info: PiScreen display by OzzMaker.com
3425 Load: dtoverlay=piscreen,<param>=<val>
3426 Params: speed Display SPI bus speed
3428 rotate Display rotation {0,90,180,270}
3430 fps Delay between frame updates
3432 debug Debug output level {0-7}
3434 xohms Touchpanel sensitivity (X-plate resistance)
3436 drm Select the DRM/KMS driver instead of the FBTFT
3441 Info: PiScreen 2 with resistive TP display by OzzMaker.com
3442 Load: dtoverlay=piscreen2r,<param>=<val>
3443 Params: speed Display SPI bus speed
3445 rotate Display rotation {0,90,180,270}
3447 fps Delay between frame updates
3449 debug Debug output level {0-7}
3451 xohms Touchpanel sensitivity (X-plate resistance)
3455 Info: Configures the Blokas Labs pisound card
3456 Load: dtoverlay=pisound
3461 Info: Adafruit PiTFT 2.2" screen
3462 Load: dtoverlay=pitft22,<param>=<val>
3463 Params: speed Display SPI bus speed
3465 rotate Display rotation {0,90,180,270}
3467 fps Delay between frame updates
3469 debug Debug output level {0-7}
3472 Name: pitft28-capacitive
3473 Info: Adafruit PiTFT 2.8" capacitive touch screen
3474 Load: dtoverlay=pitft28-capacitive,<param>=<val>
3475 Params: speed Display SPI bus speed
3477 rotate Display rotation {0,90,180,270}
3479 fps Delay between frame updates
3481 debug Debug output level {0-7}
3483 touch-sizex Touchscreen size x (default 240)
3485 touch-sizey Touchscreen size y (default 320)
3487 touch-invx Touchscreen inverted x axis
3489 touch-invy Touchscreen inverted y axis
3491 touch-swapxy Touchscreen swapped x y axis
3494 Name: pitft28-resistive
3495 Info: Adafruit PiTFT 2.8" resistive touch screen
3496 Load: dtoverlay=pitft28-resistive,<param>=<val>
3497 Params: speed Display SPI bus speed
3499 rotate Display rotation {0,90,180,270}
3501 fps Delay between frame updates
3503 debug Debug output level {0-7}
3505 drm Force the use of the mi0283qt DRM driver (by
3506 default the ili9340 framebuffer driver will
3507 be used in preference if available)
3510 Name: pitft35-resistive
3511 Info: Adafruit PiTFT 3.5" resistive touch screen
3512 Load: dtoverlay=pitft35-resistive,<param>=<val>
3513 Params: speed Display SPI bus speed
3515 rotate Display rotation {0,90,180,270}
3517 fps Delay between frame updates
3519 debug Debug output level {0-7}
3521 drm Force the use of the hx8357d DRM driver (by
3522 default the fb_hx8357d framebuffer driver will
3523 be used in preference if available)
3527 Info: Configures the pps-gpio (pulse-per-second time signal via GPIO).
3528 Load: dtoverlay=pps-gpio,<param>=<val>
3529 Params: gpiopin Input GPIO (default "18")
3530 assert_falling_edge When present, assert is indicated by a falling
3531 edge, rather than by a rising edge (default
3533 capture_clear Generate clear events on the trailing edge
3535 pull Desired pull-up/down state (off, down, up)
3540 Info: Configures the PROTO Audio Codec card
3541 Load: dtoverlay=proto-codec
3546 Info: Configures a single PWM channel
3547 Legal pin,function combinations for each channel:
3548 PWM0: 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3549 PWM1: 13,4(Alt0) 19,2(Alt5) 41,4(Alt0) 45,4(Alt0) 53,5(Alt1)
3551 1) Pin 18 is the only one available on all platforms, and
3552 it is the one used by the I2S audio interface.
3553 Pins 12 and 13 might be better choices on an A+, B+ or Pi2.
3554 2) The onboard analogue audio output uses both PWM channels.
3555 3) So be careful mixing audio and PWM.
3556 4) Currently the clock must have been enabled and configured
3558 Load: dtoverlay=pwm,<param>=<val>
3559 Params: pin Output pin (default 18) - see table
3560 func Pin function (default 2 = Alt5) - see above
3561 clock PWM clock frequency (informational)
3565 Info: Configures both PWM channels
3566 Legal pin,function combinations for each channel:
3567 PWM0: 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3568 PWM1: 13,4(Alt0) 19,2(Alt5) 41,4(Alt0) 45,4(Alt0) 53,5(Alt1)
3570 1) Pin 18 is the only one available on all platforms, and
3571 it is the one used by the I2S audio interface.
3572 Pins 12 and 13 might be better choices on an A+, B+ or Pi2.
3573 2) The onboard analogue audio output uses both PWM channels.
3574 3) So be careful mixing audio and PWM.
3575 4) Currently the clock must have been enabled and configured
3577 Load: dtoverlay=pwm-2chan,<param>=<val>
3578 Params: pin Output pin (default 18) - see table
3579 pin2 Output pin for other channel (default 19)
3580 func Pin function (default 2 = Alt5) - see above
3581 func2 Function for pin2 (default 2 = Alt5)
3582 clock PWM clock frequency (informational)
3586 Info: Use GPIO pin as pwm-assisted infrared transmitter output.
3587 This is an alternative to "gpio-ir-tx". pwm-ir-tx makes use
3588 of PWM0 to reduce the CPU load during transmission compared to
3589 gpio-ir-tx which uses bit-banging.
3590 Legal pin,function combinations are:
3591 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3592 Load: dtoverlay=pwm-ir-tx,<param>=<val>
3593 Params: gpio_pin Output GPIO (default 18)
3595 func Pin function (default 2 = Alt5)
3599 Info: Configures one or two PWM channel on PWM1 (BCM2711 only)
3601 1) The onboard analogue audio output uses both PWM channels.
3602 2) So be careful mixing audio and PWM.
3603 Note that even when only one pin is enabled, both channels are available
3604 from the PWM driver, so be careful to use the correct one.
3605 Load: dtoverlay=pwm1,<param>=<val>
3606 Params: clock PWM clock frequency (informational)
3607 pins_40 Enable channel 0 (PWM1_0) on GPIO 40
3608 pins_41 Enable channel 1 (PWM1_1) on GPIO 41
3609 pins_40_41 Enable channels 0 (PWM1_0) and 1 (PW1_1) on
3610 GPIOs 40 and 41 (default)
3611 pull_up Enable pull-ups on the PWM pins (default)
3612 pull_down Enable pull-downs on the PWM pins
3613 pull_off Disable pulls on the PWM pins
3617 Info: in-tech's Evaluation Board for PLC Stamp micro
3618 This uses spi0 and a separate GPIO interrupt to connect the QCA7000.
3619 Load: dtoverlay=qca7000,<param>=<val>
3620 Params: int_pin GPIO pin for interrupt signal (default 23)
3622 speed SPI bus speed (default 12 MHz)
3626 Info: in-tech's Evaluation Board for PLC Stamp micro (UART)
3627 This uses uart0/ttyAMA0 over GPIOs 14 & 15 to connect the QCA7000.
3628 But it requires disabling of onboard Bluetooth on
3629 Pi 3B, 3B+, 3A+, 4B and Zero W.
3630 Load: dtoverlay=qca7000-uart0,<param>=<val>
3631 Params: baudrate Set the baudrate for the UART (default
3636 Info: Enable the preservation of crash logs across a reboot. With
3637 systemd-pstore enabled (as it is on Raspberry Pi OS) the crash logs
3638 are moved to /var/lib/systemd/pstore/ on reboot.
3639 Load: dtoverlay=ramoops,<param>=<val>
3640 Params: base-addr Where to place the capture buffer (default
3642 total-size How much memory to allocate altogether (in
3643 bytes - default 64kB)
3644 record-size How much space to use for each capture, i.e.
3645 total-size / record-size = number of captures
3647 console-size Size of non-panic dmesg captures (default 0)
3651 Info: The version of the ramoops overlay for the Pi 4 family. It should be
3652 loaded automatically if dtoverlay=ramoops is specified on a Pi 4.
3653 Load: dtoverlay=ramoops-pi4,<param>=<val>
3654 Params: base-addr Where to place the capture buffer (default
3656 total-size How much memory to allocate altogether (in
3657 bytes - default 64kB)
3658 record-size How much space to use for each capture, i.e.
3659 total-size / record-size = number of captures
3661 console-size Size of non-panic dmesg captures (default 0)
3664 Name: rotary-encoder
3665 Info: Overlay for GPIO connected rotary encoder.
3666 Load: dtoverlay=rotary-encoder,<param>=<val>
3667 Params: pin_a GPIO connected to rotary encoder channel A
3669 pin_b GPIO connected to rotary encoder channel B
3671 relative_axis register a relative axis rather than an
3672 absolute one. Relative axis will only
3673 generate +1/-1 events on the input device,
3674 hence no steps need to be passed.
3675 linux_axis the input subsystem axis to map to this
3676 rotary encoder. Defaults to 0 (ABS_X / REL_X)
3677 rollover Automatic rollover when the rotary value
3678 becomes greater than the specified steps or
3679 smaller than 0. For absolute axis only.
3680 steps-per-period Number of steps (stable states) per period.
3681 The values have the following meaning:
3682 1: Full-period mode (default)
3684 4: Quarter-period mode
3685 steps Number of steps in a full turnaround of the
3686 encoder. Only relevant for absolute axis.
3687 Defaults to 24 which is a typical value for
3689 wakeup Boolean, rotary encoder can wake up the
3691 encoding String, the method used to encode steps.
3692 Supported are "gray" (the default and more
3693 common) and "binary".
3697 Info: Raspberry Pi official display backlight driver
3698 Load: dtoverlay=rpi-backlight
3702 Name: rpi-cirrus-wm5102
3703 Info: This overlay has been renamed to cirrus-wm5102
3708 Info: Configures the Raspberry Pi Codec Zero sound card
3709 Load: dtoverlay=rpi-codeczero
3714 Info: This overlay has been renamed to i2s-dac.
3719 Info: Configures the Raspberry Pi DAC+ card
3720 Load: dtoverlay=rpi-dacplus,<param>=<val>
3721 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3722 digital volume control. Enable by adding
3723 "dtparam=24db_digital_gain" to config.txt
3724 before any "dtoverlay" lines.
3725 The default behaviour is that the digital
3726 volume control is limited to a maximum of
3727 0dB. ie. it can attenuate but not provide
3728 gain. For most users, this will be desired
3729 as it will prevent clipping. By appending
3730 the 24db_digital_gain parameter, the digital
3731 volume control will allow up to 24dB of
3732 gain. If this parameter is enabled, it is the
3733 responsibility of the user to ensure that
3734 the digital volume control is set to a value
3735 that does not result in clipping/distortion!
3739 Info: Configures the Raspberry Pi DAC Pro sound card
3740 Load: dtoverlay=rpi-dacpro,<param>=<val>
3741 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3742 digital volume control. Enable by adding
3743 "dtparam=24db_digital_gain" to config.txt
3744 before any "dtoverlay" lines.
3745 The default behaviour is that the digital
3746 volume control is limited to a maximum of
3747 0dB. ie. it can attenuate but not provide
3748 gain. For most users, this will be desired
3749 as it will prevent clipping. By appending
3750 the 24db_digital_gain parameter, the digital
3751 volume control will allow up to 24dB of
3752 gain. If this parameter is enabled, it is the
3753 responsibility of the user to ensure that
3754 the digital volume control is set to a value
3755 that does not result in clipping/distortion!
3758 Name: rpi-digiampplus
3759 Info: Configures the Raspberry Pi DigiAMP+ sound card
3760 Load: dtoverlay=rpi-digiampplus,<param>=<val>
3761 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3762 digital volume control. Enable by adding
3763 "dtparam=24db_digital_gain" to config.txt
3764 before any "dtoverlay" lines.
3765 The default behaviour is that the digital
3766 volume control is limited to a maximum of
3767 0dB. ie. it can attenuate but not provide
3768 gain. For most users, this will be desired
3769 as it will prevent clipping. By appending
3770 the 24db_digital_gain parameter, the digital
3771 volume control will allow up to 24dB of
3772 gain. If this parameter is enabled, it is the
3773 responsibility of the user to ensure that
3774 the digital volume control is set to a value
3775 that does not result in clipping/distortion!
3776 auto_mute_amp If specified, unmute/mute the DigiAMP+ when
3777 starting/stopping audio playback (default "on").
3778 unmute_amp If specified, unmute the DigiAMP+ amp once when
3779 the DAC driver module loads (default "off").
3783 Info: This overlay has been renamed to watterott-display
3788 Info: Official Raspberry Pi display touchscreen
3789 Load: dtoverlay=rpi-ft5406,<param>=<val>
3790 Params: touchscreen-size-x Touchscreen X resolution (default 800)
3791 touchscreen-size-y Touchscreen Y resolution (default 480);
3792 touchscreen-inverted-x Invert touchscreen X coordinates (default 0);
3793 touchscreen-inverted-y Invert touchscreen Y coordinates (default 0);
3794 touchscreen-swapped-x-y Swap X and Y cordinates (default 0);
3798 Info: Raspberry Pi PoE HAT fan
3799 Load: dtoverlay=rpi-poe,<param>[=<val>]
3800 Params: poe_fan_temp0 Temperature (in millicelcius) at which the fan
3801 turns on (default 40000)
3802 poe_fan_temp0_hyst Temperature delta (in millicelcius) at which
3803 the fan turns off (default 2000)
3804 poe_fan_temp1 Temperature (in millicelcius) at which the fan
3805 speeds up (default 45000)
3806 poe_fan_temp1_hyst Temperature delta (in millicelcius) at which
3807 the fan slows down (default 2000)
3808 poe_fan_temp2 Temperature (in millicelcius) at which the fan
3809 speeds up (default 50000)
3810 poe_fan_temp2_hyst Temperature delta (in millicelcius) at which
3811 the fan slows down (default 2000)
3812 poe_fan_temp3 Temperature (in millicelcius) at which the fan
3813 speeds up (default 55000)
3814 poe_fan_temp3_hyst Temperature delta (in millicelcius) at which
3815 the fan slows down (default 5000)
3816 i2c Control the fan via Linux I2C drivers instead of
3821 Info: Raspberry Pi PoE+ HAT fan
3822 Load: dtoverlay=rpi-poe-plus,<param>[=<val>]
3823 Params: poe_fan_temp0 Temperature (in millicelcius) at which the fan
3824 turns on (default 40000)
3825 poe_fan_temp0_hyst Temperature delta (in millicelcius) at which
3826 the fan turns off (default 2000)
3827 poe_fan_temp1 Temperature (in millicelcius) at which the fan
3828 speeds up (default 45000)
3829 poe_fan_temp1_hyst Temperature delta (in millicelcius) at which
3830 the fan slows down (default 2000)
3831 poe_fan_temp2 Temperature (in millicelcius) at which the fan
3832 speeds up (default 50000)
3833 poe_fan_temp2_hyst Temperature delta (in millicelcius) at which
3834 the fan slows down (default 2000)
3835 poe_fan_temp3 Temperature (in millicelcius) at which the fan
3836 speeds up (default 55000)
3837 poe_fan_temp3_hyst Temperature delta (in millicelcius) at which
3838 the fan slows down (default 5000)
3839 i2c Control the fan via Linux I2C drivers instead of
3844 Info: This overlay has been renamed to proto-codec.
3849 Info: Raspberry Pi Sense HAT
3850 Load: dtoverlay=rpi-sense
3855 Info: Raspberry Pi Sense HAT v2
3856 Load: dtoverlay=rpi-sense-v2
3861 Info: Raspberry Pi TV HAT
3862 Load: dtoverlay=rpi-tv
3867 Info: This overlay has been deprecated and deleted as the V4L2 stateless
3868 video decoder driver is enabled by default.
3872 Name: rra-digidac1-wm8741-audio
3873 Info: Configures the Red Rocks Audio DigiDAC1 soundcard
3874 Load: dtoverlay=rra-digidac1-wm8741-audio
3879 Info: Overlay for the SPI-connected Sainsmart 1.8" display (based on the
3881 Load: dtoverlay=sainsmart18,<param>=<val>
3882 Params: rotate Display rotation {0,90,180,270}
3883 speed SPI bus speed in Hz (default 4000000)
3884 fps Display frame rate in Hz
3885 bgr Enable BGR mode (default off)
3886 debug Debug output level {0-7}
3887 dc_pin GPIO pin for D/C (default 24)
3888 reset_pin GPIO pin for RESET (default 25)
3892 Info: Overlay for the NXP SC16IS750 UART with I2C Interface
3893 Enables the chip on I2C1 at 0x48 (or the "addr" parameter value). To
3894 select another address, please refer to table 10 in reference manual.
3895 Load: dtoverlay=sc16is750-i2c,<param>=<val>
3896 Params: int_pin GPIO used for IRQ (default 24)
3897 addr Address (default 0x48)
3898 xtal On-board crystal frequency (default 14745600)
3902 Info: Overlay for the NXP SC16IS752 dual UART with I2C Interface
3903 Enables the chip on I2C1 at 0x48 (or the "addr" parameter value). To
3904 select another address, please refer to table 10 in reference manual.
3905 Load: dtoverlay=sc16is752-i2c,<param>=<val>
3906 Params: int_pin GPIO used for IRQ (default 24)
3907 addr Address (default 0x48)
3908 xtal On-board crystal frequency (default 14745600)
3911 Name: sc16is752-spi0
3912 Info: Overlay for the NXP SC16IS752 Dual UART with SPI Interface
3913 Enables the chip on SPI0.
3914 Load: dtoverlay=sc16is752-spi0,<param>=<val>
3915 Params: int_pin GPIO used for IRQ (default 24)
3916 xtal On-board crystal frequency (default 14745600)
3919 Name: sc16is752-spi1
3920 Info: Overlay for the NXP SC16IS752 Dual UART with SPI Interface
3921 Enables the chip on SPI1.
3922 N.B.: spi1 is only accessible on devices with a 40pin header, eg:
3923 A+, B+, Zero and PI2 B; as well as the Compute Module.
3925 Load: dtoverlay=sc16is752-spi1,<param>=<val>
3926 Params: int_pin GPIO used for IRQ (default 24)
3927 xtal On-board crystal frequency (default 14745600)
3931 Info: Selects the bcm2835-sdhost SD/MMC driver, optionally with overclock.
3932 N.B. This overlay is designed for situations where the mmc driver is
3933 the default, so it disables the other (mmc) interface - this will kill
3934 WLAN on a Pi3. If this isn't what you want, either use the sdtweak
3935 overlay or the new sd_* dtparams of the base DTBs.
3936 Load: dtoverlay=sdhost,<param>=<val>
3937 Params: overclock_50 Clock (in MHz) to use when the MMC framework
3940 force_pio Disable DMA support (default off)
3942 pio_limit Number of blocks above which to use DMA
3945 debug Enable debug output (default off)
3949 Info: Selects the bcm2835-sdhost SD/MMC driver, optionally with overclock,
3950 and enables SDIO via GPIOs 22-27. An example of use in 1-bit mode is
3951 "dtoverlay=sdio,bus_width=1,gpios_22_25"
3952 Load: dtoverlay=sdio,<param>=<val>
3953 Params: sdio_overclock SDIO Clock (in MHz) to use when the MMC
3954 framework requests 50MHz
3956 poll_once Disable SDIO-device polling every second
3957 (default on: polling once at boot-time)
3959 bus_width Set the SDIO host bus width (default 4 bits)
3961 gpios_22_25 Select GPIOs 22-25 for 1-bit mode. Must be used
3962 with bus_width=1. This replaces the sdio-1bit
3963 overlay, which is now deprecated.
3965 gpios_34_37 Select GPIOs 34-37 for 1-bit mode. Must be used
3968 gpios_34_39 Select GPIOs 34-39 for 4-bit mode. Must be used
3969 with bus_width=4 (the default).
3973 Info: This overlay is now deprecated. Use
3974 "dtoverlay=sdio,bus_width=1,gpios_22_25" instead.
3979 Info: Selects the rp1_mmc0 interface and enables it on GPIOs 22-27.
3981 Load: dtoverlay=sdio-pi5
3986 Info: This overlay is now deprecated. Use the sd_* dtparams in the
3987 base DTB, e.g. "dtoverlay=sdtweak,poll_once" becomes
3988 "dtparam=sd_poll_once".
3992 Name: seeed-can-fd-hat-v1
3993 Info: Overlay for Seeed Studio CAN BUS FD HAT with two CAN FD
3994 channels without RTC. Use this overlay if your HAT has no
3996 https://www.seeedstudio.com/2-Channel-CAN-BUS-FD-Shield-for-Raspberry-Pi-p-4072.html
3997 Load: dtoverlay=seeed-can-fd-hat-v1
4001 Name: seeed-can-fd-hat-v2
4002 Info: Overlay for Seeed Studio CAN BUS FD HAT with two CAN FD
4003 channels and an RTC. Use this overlay if your HAT has a
4005 https://www.seeedstudio.com/CAN-BUS-FD-HAT-for-Raspberry-Pi-p-4742.html
4006 Load: dtoverlay=seeed-can-fd-hat-v2
4011 Info: Overlay for SH1106 OLED via SPI using fbtft staging driver.
4012 Load: dtoverlay=sh1106-spi,<param>=<val>
4013 Params: speed SPI bus speed (default 4000000)
4014 rotate Display rotation (0, 90, 180 or 270; default 0)
4015 fps Delay between frame updates (default 25)
4016 debug Debug output level (0-7; default 0)
4017 dc_pin GPIO pin for D/C (default 24)
4018 reset_pin GPIO pin for RESET (default 25)
4019 height Display height (32 or 64; default 64)
4023 Info: Overlay for Si446x UHF Transceiver via SPI using si446x driver.
4024 The driver is currently out-of-tree at
4025 https://github.com/sunipkmukherjee/silabs.git
4026 Load: dtoverlay=si446x-spi0,<param>=<val>
4027 Params: speed SPI bus speed (default 4000000)
4028 int_pin GPIO pin for interrupts (default 17)
4029 reset_pin GPIO pin for RESET (default 27)
4033 Info: Enables the Secondary Memory Interface peripheral. Uses GPIOs 2-25!
4039 Info: Enables the userspace interface for the SMI driver
4040 Load: dtoverlay=smi-dev
4045 Info: Enables access to NAND flash via the SMI interface
4046 Load: dtoverlay=smi-nand
4051 Info: Move SPI function block to GPIO 35 to 39
4052 Load: dtoverlay=spi-gpio35-39
4057 Info: Move SPI function block to GPIOs 40 to 45
4058 Load: dtoverlay=spi-gpio40-45
4063 Info: Adds support for a number of SPI Real Time Clock devices
4064 Load: dtoverlay=spi-rtc,<param>=<val>
4065 Params: ds3232 Select the DS3232 device
4066 ds3234 Select the DS3234 device
4067 pcf2123 Select the PCF2123 device
4069 spi0_0 Use spi0.0 (default)
4075 cs_high This device requires an active-high CS
4079 Info: Don't claim any CS pins for SPI0. Requires a device with its chip
4080 select permanently enabled, but frees a GPIO for e.g. a DPI display.
4081 Load: dtoverlay=spi0-0cs,<param>=<val>
4082 Params: no_miso Don't claim and use the MISO pin (9), freeing
4087 Info: Only use one CS pin for SPI0
4088 Load: dtoverlay=spi0-1cs,<param>=<val>
4089 Params: cs0_pin GPIO pin for CS0 (default 8)
4090 no_miso Don't claim and use the MISO pin (9), freeing
4095 Info: Change the CS pins for SPI0
4096 Load: dtoverlay=spi0-2cs,<param>=<val>
4097 Params: cs0_pin GPIO pin for CS0 (default 8)
4098 cs1_pin GPIO pin for CS1 (default 7)
4099 no_miso Don't claim and use the MISO pin (9), freeing
4104 Info: This overlay has been renamed spi0-2cs, keeping spi0-cs as an
4105 alias for backwards compatibility.
4110 Info: This overlay has been deprecated and removed because it is no longer
4111 necessary and has been seen to prevent spi0 from working.
4116 Info: Enables spi1 with a single chip select (CS) line and associated spidev
4117 dev node. The gpio pin number for the CS line and spidev device node
4118 creation are configurable.
4119 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4120 Load: dtoverlay=spi1-1cs,<param>=<val>
4121 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4122 cs0_spidev Set to 'off' to stop the creation of a
4123 userspace device node /dev/spidev1.0 (default
4124 is 'on' or enabled).
4128 Info: Enables spi1 with two chip select (CS) lines and associated spidev
4129 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4130 creation are configurable.
4131 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4132 Load: dtoverlay=spi1-2cs,<param>=<val>
4133 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4134 cs1_pin GPIO pin for CS1 (default 17 - BCM SPI1_CE1).
4135 cs0_spidev Set to 'off' to stop the creation of a
4136 userspace device node /dev/spidev1.0 (default
4137 is 'on' or enabled).
4138 cs1_spidev Set to 'off' to stop the creation of a
4139 userspace device node /dev/spidev1.1 (default
4140 is 'on' or enabled).
4144 Info: Enables spi1 with three chip select (CS) lines and associated spidev
4145 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4146 creation are configurable.
4147 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4148 Load: dtoverlay=spi1-3cs,<param>=<val>
4149 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4150 cs1_pin GPIO pin for CS1 (default 17 - BCM SPI1_CE1).
4151 cs2_pin GPIO pin for CS2 (default 16 - BCM SPI1_CE2).
4152 cs0_spidev Set to 'off' to stop the creation of a
4153 userspace device node /dev/spidev1.0 (default
4154 is 'on' or enabled).
4155 cs1_spidev Set to 'off' to stop the creation of a
4156 userspace device node /dev/spidev1.1 (default
4157 is 'on' or enabled).
4158 cs2_spidev Set to 'off' to stop the creation of a
4159 userspace device node /dev/spidev1.2 (default
4160 is 'on' or enabled).
4164 Info: Enables spi2 on GPIOs 40-42 with a single chip select (CS) line and
4165 associated spidev dev node. The gpio pin number for the CS line and
4166 spidev device node creation are configurable. spi2-2cs-pi5 is
4167 substituted on a Pi 5.
4168 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4169 Load: dtoverlay=spi2-1cs,<param>=<val>
4170 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4171 cs0_spidev Set to 'off' to stop the creation of a
4172 userspace device node /dev/spidev2.0 (default
4173 is 'on' or enabled).
4177 Info: Enables spi2 on GPIOs 1-3 with a single chip select (CS) line and
4178 associated spidev dev node. The gpio pin number for the CS line and
4179 spidev device node creation are configurable. Pi 5 only.
4180 Load: dtoverlay=spi2-1cs-pi5,<param>=<val>
4181 Params: cs0_pin GPIO pin for CS0 (default 0).
4182 cs0_spidev Set to 'off' to stop the creation of a
4183 userspace device node /dev/spidev2.0 (default
4184 is 'on' or enabled).
4188 Info: Enables spi2 on GPIOs 40-42 with two chip select (CS) lines and
4189 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4190 spidev device node creation are configurable. spi2-2cs-pi5 is
4191 substituted on a Pi 5.
4192 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4193 Load: dtoverlay=spi2-2cs,<param>=<val>
4194 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4195 cs1_pin GPIO pin for CS1 (default 44 - BCM SPI2_CE1).
4196 cs0_spidev Set to 'off' to stop the creation of a
4197 userspace device node /dev/spidev2.0 (default
4198 is 'on' or enabled).
4199 cs1_spidev Set to 'off' to stop the creation of a
4200 userspace device node /dev/spidev2.1 (default
4201 is 'on' or enabled).
4205 Info: Enables spi2 on GPIOs 1-3 with two chip select (CS) lines and
4206 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4207 spidev device node creation are configurable. Pi 5 only.
4208 Load: dtoverlay=spi2-2cs-pi5,<param>=<val>
4209 Params: cs0_pin GPIO pin for CS0 (default 0).
4210 cs1_pin GPIO pin for CS1 (default 24).
4211 cs0_spidev Set to 'off' to stop the creation of a
4212 userspace device node /dev/spidev2.0 (default
4213 is 'on' or enabled).
4214 cs1_spidev Set to 'off' to stop the creation of a
4215 userspace device node /dev/spidev2.1 (default
4216 is 'on' or enabled).
4220 Info: Enables spi2 on GPIOs 40-42 with three chip select (CS) lines and
4221 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4222 spidev device node creation are configurable.
4223 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4224 Load: dtoverlay=spi2-3cs,<param>=<val>
4225 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4226 cs1_pin GPIO pin for CS1 (default 44 - BCM SPI2_CE1).
4227 cs2_pin GPIO pin for CS2 (default 45 - BCM SPI2_CE2).
4228 cs0_spidev Set to 'off' to stop the creation of a
4229 userspace device node /dev/spidev2.0 (default
4230 is 'on' or enabled).
4231 cs1_spidev Set to 'off' to stop the creation of a
4232 userspace device node /dev/spidev2.1 (default
4233 is 'on' or enabled).
4234 cs2_spidev Set to 'off' to stop the creation of a
4235 userspace device node /dev/spidev2.2 (default
4236 is 'on' or enabled).
4240 Info: Enables spi3 on GPIOs 1-3 with a single chip select (CS) line and
4241 associated spidev dev node. The gpio pin number for the CS line and
4242 spidev device node creation are configurable. BCM2711 only,
4243 spi3-1cs-pi5 is substituted on Pi 5.
4244 Load: dtoverlay=spi3-1cs,<param>=<val>
4245 Params: cs0_pin GPIO pin for CS0 (default 0 - BCM SPI3_CE0).
4246 cs0_spidev Set to 'off' to prevent the creation of a
4247 userspace device node /dev/spidev3.0 (default
4248 is 'on' or enabled).
4252 Info: Enables spi3 on GPIOs 5-7 with a single chip select (CS) line and
4253 associated spidev dev node. The gpio pin number for the CS line and
4254 spidev device node creation are configurable. Pi 5 only.
4255 Load: dtoverlay=spi3-1cs-pi5,<param>=<val>
4256 Params: cs0_pin GPIO pin for CS0 (default 4).
4257 cs0_spidev Set to 'off' to prevent the creation of a
4258 userspace device node /dev/spidev3.0 (default
4259 is 'on' or enabled).
4263 Info: Enables spi3 on GPIO2 1-3 with two chip select (CS) lines and
4264 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4265 spidev device node creation are configurable. BCM2711 only,
4266 spi3-2cs-pi5 is substituted on Pi 5.
4267 Load: dtoverlay=spi3-2cs,<param>=<val>
4268 Params: cs0_pin GPIO pin for CS0 (default 0 - BCM SPI3_CE0).
4269 cs1_pin GPIO pin for CS1 (default 24 - BCM SPI3_CE1).
4270 cs0_spidev Set to 'off' to prevent the creation of a
4271 userspace device node /dev/spidev3.0 (default
4272 is 'on' or enabled).
4273 cs1_spidev Set to 'off' to prevent the creation of a
4274 userspace device node /dev/spidev3.1 (default
4275 is 'on' or enabled).
4279 Info: Enables spi3 on GPIOs 5-7 with two chip select (CS) lines and
4280 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4281 spidev device node creation are configurable. Pi 5 only.
4282 Load: dtoverlay=spi3-2cs-pi5,<param>=<val>
4283 Params: cs0_pin GPIO pin for CS0 (default 4).
4284 cs1_pin GPIO pin for CS1 (default 25).
4285 cs0_spidev Set to 'off' to prevent the creation of a
4286 userspace device node /dev/spidev3.0 (default
4287 is 'on' or enabled).
4288 cs1_spidev Set to 'off' to prevent the creation of a
4289 userspace device node /dev/spidev3.1 (default
4290 is 'on' or enabled).
4294 Info: Enables spi4 on GPIOs 5-7 with a single chip select (CS) line and
4295 associated spidev dev node. The gpio pin number for the CS line and
4296 spidev device node creation are configurable. BCM2711 only.
4297 Load: dtoverlay=spi4-1cs,<param>=<val>
4298 Params: cs0_pin GPIO pin for CS0 (default 4 - BCM SPI4_CE0).
4299 cs0_spidev Set to 'off' to prevent the creation of a
4300 userspace device node /dev/spidev4.0 (default
4301 is 'on' or enabled).
4305 Info: Enables spi4 on GPIOs 5-6 with two chip select (CS) lines and
4306 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4307 spidev device node creation are configurable. BCM2711 only.
4308 Load: dtoverlay=spi4-2cs,<param>=<val>
4309 Params: cs0_pin GPIO pin for CS0 (default 4 - BCM SPI4_CE0).
4310 cs1_pin GPIO pin for CS1 (default 25 - BCM SPI4_CE1).
4311 cs0_spidev Set to 'off' to prevent the creation of a
4312 userspace device node /dev/spidev4.0 (default
4313 is 'on' or enabled).
4314 cs1_spidev Set to 'off' to prevent the creation of a
4315 userspace device node /dev/spidev4.1 (default
4316 is 'on' or enabled).
4320 Info: Enables spi5 on GPIOs 13-15 with a single chip select (CS) line and
4321 associated spidev dev node. The gpio pin numbers for the CS lines and
4322 spidev device node creation are configurable. BCM2711 and Pi 5.
4323 Load: dtoverlay=spi5-1cs,<param>=<val>
4324 Params: cs0_pin GPIO pin for CS0 (default 12).
4325 cs0_spidev Set to 'off' to prevent the creation of a
4326 userspace device node /dev/spidev5.0 (default
4327 is 'on' or enabled).
4335 Info: Enables spi5 on GPIOs 13-15 with two chip select (CS) lines and
4336 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4337 spidev device node creation are configurable. BCM2711 and Pi 5.
4338 Load: dtoverlay=spi5-2cs,<param>=<val>
4339 Params: cs0_pin GPIO pin for CS0 (default 12).
4340 cs1_pin GPIO pin for CS1 (default 26).
4341 cs0_spidev Set to 'off' to prevent the creation of a
4342 userspace device node /dev/spidev5.0 (default
4343 is 'on' or enabled).
4344 cs1_spidev Set to 'off' to prevent the creation of a
4345 userspace device node /dev/spidev5.1 (default
4346 is 'on' or enabled).
4354 Info: Enables spi6 with a single chip select (CS) line and associated spidev
4355 dev node. The gpio pin number for the CS line and spidev device node
4356 creation are configurable. BCM2711 only.
4357 Load: dtoverlay=spi6-1cs,<param>=<val>
4358 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI6_CE0).
4359 cs0_spidev Set to 'off' to prevent the creation of a
4360 userspace device node /dev/spidev6.0 (default
4361 is 'on' or enabled).
4365 Info: Enables spi6 with two chip select (CS) lines and associated spidev
4366 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4367 creation are configurable. BCM2711 only.
4368 Load: dtoverlay=spi6-2cs,<param>=<val>
4369 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI6_CE0).
4370 cs1_pin GPIO pin for CS1 (default 27 - BCM SPI6_CE1).
4371 cs0_spidev Set to 'off' to prevent the creation of a
4372 userspace device node /dev/spidev6.0 (default
4373 is 'on' or enabled).
4374 cs1_spidev Set to 'off' to prevent the creation of a
4375 userspace device node /dev/spidev6.1 (default
4376 is 'on' or enabled).
4380 Info: Overlay for activation of SSD1306 over I2C OLED display framebuffer.
4381 Load: dtoverlay=ssd1306,<param>=<val>
4382 Params: address Location in display memory of first character.
4384 width Width of display. (default=128)
4385 height Height of display. (default=64)
4386 offset virtual channel a. (default=0)
4387 normal Has no effect on displays tested. (default=not
4389 sequential Set this if every other scan line is missing.
4391 remapped Set this if display is garbled. (default=not
4393 inverted Set this if display is inverted and mirrored.
4397 Typical usage for 128x64 display: dtoverlay=ssd1306,inverted
4399 Typical usage for 128x32 display: dtoverlay=ssd1306,inverted,sequential
4401 i2c_baudrate=400000 will speed up the display.
4403 i2c_baudrate=1000000 seems to work even though it's not officially
4404 supported by the hardware, and is faster still.
4406 For more information refer to the device datasheet at:
4407 https://cdn-shop.adafruit.com/datasheets/SSD1306.pdf
4411 Info: Overlay for SSD1306 OLED via SPI using fbtft staging driver.
4412 Load: dtoverlay=ssd1306-spi,<param>=<val>
4413 Params: speed SPI bus speed (default 10000000)
4414 rotate Display rotation (0, 90, 180 or 270; default 0)
4415 fps Delay between frame updates (default 25)
4416 debug Debug output level (0-7; default 0)
4417 dc_pin GPIO pin for D/C (default 24)
4418 reset_pin GPIO pin for RESET (default 25)
4419 height Display height (32 or 64; default 64)
4420 inverted Set this if display is inverted and mirrored.
4425 Info: Overlay for SSD1331 OLED via SPI using fbtft staging driver.
4426 Load: dtoverlay=ssd1331-spi,<param>=<val>
4427 Params: speed SPI bus speed (default 4500000)
4428 rotate Display rotation (0, 90, 180 or 270; default 0)
4429 fps Delay between frame updates (default 25)
4430 debug Debug output level (0-7; default 0)
4431 dc_pin GPIO pin for D/C (default 24)
4432 reset_pin GPIO pin for RESET (default 25)
4436 Info: Overlay for SSD1351 OLED via SPI using fbtft staging driver.
4437 Load: dtoverlay=ssd1351-spi,<param>=<val>
4438 Params: speed SPI bus speed (default 4500000)
4439 rotate Display rotation (0, 90, 180 or 270; default 0)
4440 fps Delay between frame updates (default 25)
4441 debug Debug output level (0-7; default 0)
4442 dc_pin GPIO pin for D/C (default 24)
4443 reset_pin GPIO pin for RESET (default 25)
4446 Name: superaudioboard
4447 Info: Configures the SuperAudioBoard sound card
4448 Load: dtoverlay=superaudioboard,<param>=<val>
4449 Params: gpiopin GPIO pin for codec reset
4453 Info: Configures the Semtech SX150X I2C GPIO expanders.
4454 Load: dtoverlay=sx150x,<param>=<val>
4455 Params: sx150<x>-<n>-<m> Enables SX150X device on I2C#<n> with slave
4456 address <m>. <x> may be 1-9. <n> may be 0 or 1.
4457 Permissible values of <m> (which is denoted in
4458 hex) depend on the device variant. For SX1501,
4459 SX1502, SX1504 and SX1505, <m> may be 20 or 21.
4460 For SX1503 and SX1506, <m> may be 20. For
4461 SX1507 and SX1509, <m> may be 3E, 3F, 70 or 71.
4462 For SX1508, <m> may be 20, 21, 22 or 23.
4464 sx150<x>-<n>-<m>-int-gpio
4465 Integer, enables interrupts on SX150X device on
4466 I2C#<n> with slave address <m>, specifies
4467 the GPIO pin to which NINT output of SX150X is
4472 Info: Toshiba TC358743 HDMI to CSI-2 bridge chip.
4473 Uses Unicam 1, which is the standard camera connector on most Pi
4475 Load: dtoverlay=tc358743,<param>=<val>
4476 Params: 4lane Use 4 lanes (only applicable to Compute Modules
4479 link-frequency Set the link frequency. Only values of 297000000
4480 (574Mbit/s) and 486000000 (972Mbit/s - default)
4481 are supported by the driver.
4482 media-controller Configure use of Media Controller API for
4483 configuring the sensor (default off)
4484 cam0 Adopt the default configuration for CAM0 on a
4485 Compute Module (CSI0, i2c_vc, and cam0_reg).
4488 Name: tc358743-audio
4489 Info: Used in combination with the tc358743-fast overlay to route the audio
4490 from the TC358743 over I2S to the Pi.
4491 Wiring is LRCK/WFS to GPIO 19, BCK/SCK to GPIO 18, and DATA/SD to GPIO
4493 Load: dtoverlay=tc358743-audio,<param>=<val>
4494 Params: card-name Override the default, "tc358743", card name.
4498 Info: 3.5" Color TFT Display by www.tinylcd.com
4499 Options: Touch, RTC, keypad
4500 Load: dtoverlay=tinylcd35,<param>=<val>
4501 Params: speed Display SPI bus speed
4503 rotate Display rotation {0,90,180,270}
4505 fps Delay between frame updates
4507 debug Debug output level {0-7}
4509 touch Enable touch panel
4511 touchgpio Touch controller IRQ GPIO
4513 xohms Touchpanel: Resistance of X-plate in ohms
4515 rtc-pcf PCF8563 Real Time Clock
4517 rtc-ds DS1307 Real Time Clock
4519 keypad Enable keypad
4522 Display with touchpanel, PCF8563 RTC and keypad:
4523 dtoverlay=tinylcd35,touch,rtc-pcf,keypad
4525 dtoverlay=tinylcd35,touch,touchgpio=3
4529 Info: Enables support for Infineon SLB9670 Trusted Platform Module add-on
4530 boards, which can be used as a secure key storage and hwrng,
4531 available as "Iridium SLB9670" by Infineon and "LetsTrust TPM" by pi3g.
4532 Load: dtoverlay=tpm-slb9670
4537 Info: Enables support for Infineon SLB9673 Trusted Platform Module add-on
4538 boards, which can be used as a secure key storage and hwrng
4539 via the I2C protocol.
4540 Load: dtoverlay=tpm-slb9673
4545 Info: Change the pin usage of uart0
4546 Load: dtoverlay=uart0,<param>=<val>
4547 Params: txd0_pin GPIO pin for TXD0 (14, 32 or 36 - default 14)
4549 rxd0_pin GPIO pin for RXD0 (15, 33 or 37 - default 15)
4551 pin_func Alternative pin function - 4(Alt0) for 14&15,
4552 7(Alt3) for 32&33, 6(Alt2) for 36&37
4556 Info: Enable uart 0 on GPIOs 14-15. Pi 5 only.
4557 Load: dtoverlay=uart0-pi5,<param>
4558 Params: ctsrts Enable CTS/RTS on GPIOs 16-17 (default off)
4562 Info: Change the pin usage of uart1
4563 Load: dtoverlay=uart1,<param>=<val>
4564 Params: txd1_pin GPIO pin for TXD1 (14, 32 or 40 - default 14)
4566 rxd1_pin GPIO pin for RXD1 (15, 33 or 41 - default 15)
4570 Info: Enable uart 1 on GPIOs 0-1. Pi 5 only.
4571 Load: dtoverlay=uart1-pi5,<param>
4572 Params: ctsrts Enable CTS/RTS on GPIOs 2-3 (default off)
4576 Info: Enable uart 2 on GPIOs 0-3. BCM2711 only.
4577 Load: dtoverlay=uart2,<param>
4578 Params: ctsrts Enable CTS/RTS on GPIOs 2-3 (default off)
4582 Info: Enable uart 2 on GPIOs 4-5. Pi 5 only.
4583 Load: dtoverlay=uart2-pi5,<param>
4584 Params: ctsrts Enable CTS/RTS on GPIOs 6-7 (default off)
4588 Info: Enable uart 3 on GPIOs 4-7. BCM2711 only.
4589 Load: dtoverlay=uart3,<param>
4590 Params: ctsrts Enable CTS/RTS on GPIOs 6-7 (default off)
4594 Info: Enable uart 3 on GPIOs 8-9. Pi 5 only.
4595 Load: dtoverlay=uart3-pi5,<param>
4596 Params: ctsrts Enable CTS/RTS on GPIOs 10-11 (default off)
4600 Info: Enable uart 4 on GPIOs 8-11. BCM2711 only.
4601 Load: dtoverlay=uart4,<param>
4602 Params: ctsrts Enable CTS/RTS on GPIOs 10-11 (default off)
4606 Info: Enable uart 4 on GPIOs 12-13. Pi 5 only.
4607 Load: dtoverlay=uart4-pi5,<param>
4608 Params: ctsrts Enable CTS/RTS on GPIOs 14-15 (default off)
4612 Info: Enable uart 5 on GPIOs 12-15. BCM2711 only.
4613 Load: dtoverlay=uart5,<param>
4614 Params: ctsrts Enable CTS/RTS on GPIOs 14-15 (default off)
4618 Info: Configures the NW Digital Radio UDRC Hat
4619 Load: dtoverlay=udrc,<param>=<val>
4620 Params: alsaname Name of the ALSA audio device (default "udrc")
4623 Name: ugreen-dabboard
4624 Info: Configures the ugreen-dabboard I2S overlay
4625 This is a simple overlay based on the simple-audio-card and the dmic
4626 codec. It has the speciality that it is configured to use the codec
4627 as a master I2S device. It works for example with the Si468x DAB
4628 receiver on the uGreen DABBoard.
4629 Load: dtoverlay=ugreen-dabboard,<param>=<val>
4630 Params: card-name Override the default, "dabboard", card name.
4634 Info: Allow usage of downstream .dtb with upstream kernel. Comprises the
4635 vc4-kms-v3d and dwc2 overlays.
4636 Load: dtoverlay=upstream
4640 Name: upstream-aux-interrupt
4641 Info: This overlay has been deprecated and removed because it is no longer
4647 Info: Allow usage of downstream .dtb with upstream kernel on Pi 4. Comprises
4648 the vc4-kms-v3d-pi4 and dwc2 overlays.
4649 Load: dtoverlay=upstream-pi4
4654 Info: Enable Eric Anholt's DRM VC4 V3D driver on top of the dispmanx
4656 Load: dtoverlay=vc4-fkms-v3d,<param>
4657 Params: cma-512 CMA is 512MB (needs 1GB)
4658 cma-448 CMA is 448MB (needs 1GB)
4659 cma-384 CMA is 384MB (needs 1GB)
4660 cma-320 CMA is 320MB (needs 1GB)
4661 cma-256 CMA is 256MB (needs 1GB)
4662 cma-192 CMA is 192MB (needs 1GB)
4663 cma-128 CMA is 128MB
4666 cma-size CMA size in bytes, 4MB aligned
4667 cma-default Use upstream's default value
4670 Name: vc4-fkms-v3d-pi4
4671 Info: Enable Eric Anholt's DRM VC4 V3D driver on top of the dispmanx
4673 Load: dtoverlay=vc4-fkms-v3d-pi4,<param>
4674 Params: cma-512 CMA is 512MB (needs 1GB)
4675 cma-448 CMA is 448MB (needs 1GB)
4676 cma-384 CMA is 384MB (needs 1GB)
4677 cma-320 CMA is 320MB (needs 1GB)
4678 cma-256 CMA is 256MB (needs 1GB)
4679 cma-192 CMA is 192MB (needs 1GB)
4680 cma-128 CMA is 128MB
4683 cma-size CMA size in bytes, 4MB aligned
4684 cma-default Use upstream's default value
4687 Name: vc4-kms-dpi-at056tn53v1
4688 Info: This overlay is now deprecated - see vc4-kms-dpi-panel,at056tn53v1
4692 Name: vc4-kms-dpi-generic
4693 Info: Enable a generic DPI display under KMS. Default timings are for the
4694 Adafruit Kippah with 800x480 panel and RGB666 (GPIOs 0-21)
4695 Requires vc4-kms-v3d to be loaded.
4696 Load: dtoverlay=vc4-kms-dpi-generic,<param>=<val>
4697 Params: clock-frequency Display clock frequency (Hz)
4698 hactive Horizontal active pixels
4699 hfp Horizontal front porch
4700 hsync Horizontal sync pulse width
4701 hbp Horizontal back porch
4702 vactive Vertical active lines
4703 vfp Vertical front porch
4704 vsync Vertical sync pulse width
4705 vbp Vertical back porch
4706 hsync-invert Horizontal sync active low
4707 vsync-invert Vertical sync active low
4708 de-invert Data Enable active low
4709 pixclk-invert Negative edge pixel clock
4710 width-mm Define the screen width in mm
4711 height-mm Define the screen height in mm
4712 rgb565 Change to RGB565 output on GPIOs 0-19
4713 rgb565-padhi Change to RGB565 output on GPIOs 0-8, 12-17, and
4715 bgr666 Change to BGR666 output on GPIOs 0-21.
4716 bgr666-padhi Change to BGR666 output on GPIOs 0-9, 12-17, and
4718 rgb666-padhi Change to RGB666 output on GPIOs 0-9, 12-17, and
4720 bgr888 Change to BGR888 output on GPIOs 0-27
4721 rgb888 Change to RGB888 output on GPIOs 0-27
4722 bus-format Override the bus format for a MEDIA_BUS_FMT_*
4723 value. NB also overridden by rgbXXX overrides.
4724 backlight-gpio Defines a GPIO to be used for backlight control
4726 backlight-pwm Defines a PWM channel to be used for backlight
4727 control (default of none). NB Disables audio
4728 headphone output as that also uses PWM.
4729 backlight-pwm-chan Choose channel on &pwm node for backlight
4732 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
4733 pwm-2chan for valid options.
4734 (default 18 - note this can only work with
4736 backlight-pwm-func Pin function of GPIO used for the PWM
4738 See pwm-2chan for valid options.
4740 backlight-def-brightness
4741 Set the default brightness. Normal range 1-16.
4743 rotate Display rotation {0,90,180,270} (default 0)
4746 Name: vc4-kms-dpi-hyperpixel2r
4747 Info: Enable the KMS drivers for the Pimoroni HyperPixel2 Round DPI display.
4748 Requires vc4-kms-v3d to be loaded.
4749 Load: dtoverlay=vc4-kms-dpi-hyperpixel2r,<param>=<val>
4750 Params: disable-touch Disables the touch controller
4751 touchscreen-inverted-x Inverts X direction of touch controller
4752 touchscreen-inverted-y Inverts Y direction of touch controller
4753 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4754 rotate Display rotation {0,90,180,270} (default 0)
4757 Name: vc4-kms-dpi-hyperpixel4
4758 Info: Enable the KMS drivers for the Pimoroni HyperPixel4 DPI display.
4759 Requires vc4-kms-v3d to be loaded.
4760 Load: dtoverlay=vc4-kms-dpi-hyperpixel4,<param>=<val>
4761 Params: disable-touch Disables the touch controller
4762 touchscreen-inverted-x Inverts X direction of touch controller
4763 touchscreen-inverted-y Inverts Y direction of touch controller
4764 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4765 rotate Display rotation {0,90,180,270} (default 0)
4768 Name: vc4-kms-dpi-hyperpixel4sq
4769 Info: Enable the KMS drivers for the Pimoroni HyperPixel4 Square DPI display.
4770 Requires vc4-kms-v3d to be loaded.
4771 Load: dtoverlay=vc4-kms-dpi-hyperpixel4sq,<param>=<val>
4772 Params: disable-touch Disables the touch controller
4773 touchscreen-inverted-x Inverts X direction of touch controller
4774 touchscreen-inverted-y Inverts Y direction of touch controller
4775 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4776 rotate Display rotation {0,90,180,270} (default 0)
4779 Name: vc4-kms-dpi-panel
4780 Info: Enable a preconfigured KMS DPI panel.
4781 Requires vc4-kms-v3d to be loaded.
4782 Load: dtoverlay=vc4-kms-dpi-panel,<param>=<val>
4783 Params: at056tn53v1 Enable an Innolux 5.6in VGA TFT
4784 kippah-7inch Enable an Adafruit Kippah with 7inch panel.
4785 mzp280 Enable a Geekworm MZP280 panel.
4786 backlight-gpio Defines a GPIO to be used for backlight control
4788 backlight-pwm Defines a PWM channel to be used for backlight
4789 control (default of none). NB Disables audio
4790 headphone output as that also uses PWM.
4791 backlight-pwm-chan Choose channel on &pwm node for backlight
4794 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
4795 pwm-2chan for valid options.
4796 (default 18 - note this can only work with
4798 backlight-pwm-func Pin function of GPIO used for the PWM
4800 See pwm-2chan for valid options.
4802 backlight-def-brightness
4803 Set the default brightness. Normal range 1-16.
4805 rotate Display rotation {0,90,180,270} (default 0)
4808 Name: vc4-kms-dsi-7inch
4809 Info: Enable the Raspberry Pi DSI 7" screen.
4810 Includes the edt-ft5406 for the touchscreen element.
4811 Requires vc4-kms-v3d to be loaded.
4812 Load: dtoverlay=vc4-kms-dsi-7inch,<param>=<val>
4813 Params: sizex Touchscreen size x (default 800)
4814 sizey Touchscreen size y (default 480)
4815 invx Touchscreen inverted x axis
4816 invy Touchscreen inverted y axis
4817 swapxy Touchscreen swapped x y axis
4818 disable_touch Disables the touch screen overlay driver
4819 dsi0 Use DSI0 and i2c_csi_dsi0 (rather than
4820 the default DSI1 and i2c_csi_dsi).
4823 Name: vc4-kms-dsi-generic
4824 Info: Enable a generic DSI display under KMS.
4825 Default timings are for a 840x480 RGB888 panel.
4826 Requires vc4-kms-v3d to be loaded.
4827 Load: dtoverlay=vc4-kms-dsi-generic,<param>=<val>
4828 Params: clock-frequency Display clock frequency (Hz)
4829 hactive Horizontal active pixels
4830 hfp Horizontal front porch
4831 hsync Horizontal sync pulse width
4832 hbp Horizontal back porch
4833 vactive Vertical active lines
4834 vfp Vertical front porch
4835 vsync Vertical sync pulse width
4836 vbp Vertical back porch
4837 width-mm Define the screen width in mm
4838 height-mm Define the screen height in mm
4839 rgb565 Change to RGB565 output
4840 rgb666 Change to RGB666 output
4841 rgb666p Change to RGB666 output with pixel packing
4842 rgb888 Change to RGB888 output, this is the default
4843 one-lane Use one DSI lane for data transmission
4845 two-lane Use two DSI lanes for data transmission
4846 three-lane Use three DSI lanes for data transmission
4847 Only supported on Pi5 and CM
4848 four-lane Use four DSI lanes for data transmission
4849 Only supported on Pi5 and CM
4850 dsi0 Switch DSI port to DSI0
4851 Only supported on Pi5 and CM
4854 Name: vc4-kms-dsi-lt070me05000
4855 Info: Enable a JDI LT070ME05000 DSI display on DSI1.
4856 Note that this is a 4 lane DSI device, so it will only work on a Compute
4858 Requires vc4-kms-v3d to be loaded.
4859 Load: dtoverlay=vc4-kms-dsi-lt070me05000,<param>
4860 Params: reset GPIO for the reset signal (default 17)
4861 enable GPIO for the enable signal (default 4)
4862 dcdc-en GPIO for the DC-DC converter enable (default 5)
4865 Name: vc4-kms-dsi-lt070me05000-v2
4866 Info: Enable a JDI LT070ME05000 DSI display on DSI1 using Harlab's V2
4868 Note that this is a 4 lane DSI device, so it will only work on a Compute
4870 Requires vc4-kms-v3d to be loaded.
4871 Load: dtoverlay=vc4-kms-dsi-lt070me05000-v2
4875 Name: vc4-kms-dsi-waveshare-panel
4876 Info: Enable a Waveshare DSI touchscreen
4877 Includes the Goodix driver for the touchscreen element.
4878 The default is for the display to be using the I2C0 option for control.
4879 Use the i2c1 override if using the I2C1 wiring with jumper wires from
4880 GPIOs 2&3 (pins 3&5).
4881 invx/invy/swapxy should be used with caution as the panel specifier will
4882 set the default inversions for that panel. Always use them after the
4883 panel specifier, and be aware that you may need to set them as =0, not
4885 Requires vc4-kms-v3d to be loaded.
4886 Load: dtoverlay=vc4-kms-dsi-waveshare-panel,<param>=<val>
4887 Params: 2_8_inch 2.8" 480x640
4888 3_4_inch 3.4" 800x800 round
4889 4_0_inch 4.0" 480x800
4890 7_0_inchC 7.0" C 1024x600
4891 7_9_inch 7.9" 400x1280
4892 8_0_inch 8.0" 1280x800
4893 10_1_inch 10.1" 1280x800
4894 11_9_inch 11.9" 320x1480
4895 i2c1 Use i2c-1 with jumper wires from GPIOs 2&3
4896 disable_touch Disable the touch controller
4897 rotation Set the panel orientation property
4898 invx Touchscreen inverted x axis
4899 invy Touchscreen inverted y axis
4900 swapxy Touchscreen swapped x y axis
4901 dsi0 Use DSI0 and i2c_csi_dsi0 (rather than
4902 the default DSI1 and i2c_csi_dsi).
4905 Name: vc4-kms-kippah-7inch
4906 Info: This overlay is now deprecated - see vc4-kms-dpi-panel,kippah-7inch
4911 Info: Enable Eric Anholt's DRM VC4 HDMI/HVS/V3D driver.
4912 Load: dtoverlay=vc4-kms-v3d,<param>
4913 Params: cma-512 CMA is 512MB (needs 1GB)
4914 cma-448 CMA is 448MB (needs 1GB)
4915 cma-384 CMA is 384MB (needs 1GB)
4916 cma-320 CMA is 320MB (needs 1GB)
4917 cma-256 CMA is 256MB (needs 1GB)
4918 cma-192 CMA is 192MB (needs 1GB)
4919 cma-128 CMA is 128MB
4922 cma-size CMA size in bytes, 4MB aligned
4923 cma-default Use upstream's default value
4924 audio Enable or disable audio over HDMI (default "on")
4925 noaudio Disable all HDMI audio (default "off")
4926 composite Enable the composite output (default "off")
4927 N.B. Disables all other outputs on a Pi 4.
4928 nohdmi Disable HDMI output
4931 Name: vc4-kms-v3d-pi4
4932 Info: Enable Eric Anholt's DRM VC4 HDMI/HVS/V3D driver for Pi4.
4933 Load: dtoverlay=vc4-kms-v3d-pi4,<param>
4934 Params: cma-512 CMA is 512MB
4935 cma-448 CMA is 448MB
4936 cma-384 CMA is 384MB
4937 cma-320 CMA is 320MB
4938 cma-256 CMA is 256MB
4939 cma-192 CMA is 192MB
4940 cma-128 CMA is 128MB
4943 cma-size CMA size in bytes, 4MB aligned
4944 cma-default Use upstream's default value
4945 audio Enable or disable audio over HDMI0 (default
4947 audio1 Enable or disable audio over HDMI1 (default
4949 noaudio Disable all HDMI audio (default "off")
4950 composite Enable the composite output (disables all other
4952 nohdmi Disable both HDMI 0 & 1 outputs
4953 nohdmi0 Disable HDMI 0 output
4954 nohdmi1 Disable HDMI 1 output
4957 Name: vc4-kms-v3d-pi5
4958 Info: See vc4-kms-v3d-pi4 (this is the Pi 5 version)
4961 Name: vc4-kms-vga666
4962 Info: Enable the VGA666 (resistor ladder ADC) for the vc4-kms-v3d driver.
4963 Requires vc4-kms-v3d to be loaded.
4964 Load: dtoverlay=vc4-kms-vga666,<param>
4965 Params: ddc Enables GPIOs 0&1 as the I2C to read the EDID
4966 from the display. NB These are NOT 5V tolerant
4967 GPIOs, therefore level shifters are required.
4971 Info: Overlay for the Fen Logic VGA666 board
4972 This uses GPIOs 2-21 (so no I2C), and activates the output 2-3 seconds
4973 after the kernel has started.
4974 NOT for use with vc4-kms-v3d.
4975 Load: dtoverlay=vga666
4980 Info: Overlay to enable a VIA VL805 USB3 controller on CM4 carriers
4981 Will be loaded automatically by up-to-date firmware if "VL805=1" is
4982 set in the EEPROM config.
4983 Load: dtoverlay=vl805
4988 Info: Configures the w1-gpio Onewire interface module.
4989 Use this overlay if you *don't* need a GPIO to drive an external pullup.
4990 Load: dtoverlay=w1-gpio,<param>=<val>
4991 Params: gpiopin GPIO for I/O (default "4")
4992 pullup Now enabled by default (ignored)
4995 Name: w1-gpio-pullup
4996 Info: Configures the w1-gpio Onewire interface module.
4997 Use this overlay if you *do* need a GPIO to drive an external pullup.
4998 Load: dtoverlay=w1-gpio-pullup,<param>=<val>
4999 Params: gpiopin GPIO for I/O (default "4")
5000 extpullup GPIO for external pullup (default "5")
5001 pullup Now enabled by default (ignored)
5005 Info: Overlay for the Wiznet W5500 Ethernet Controller on SPI0
5006 Load: dtoverlay=w5500,<param>=<val>
5007 Params: int_pin GPIO used for INT (default 25)
5009 speed SPI bus speed (default 30000000)
5011 cs SPI bus Chip Select (default 0)
5014 Name: watterott-display
5015 Info: Watterott RPi-Display - 2.8" Touch Display
5016 Linux has 2 drivers that support this display and this overlay supports
5020 fbtft/fb_ili9341: dtoverlay=watterott-display
5021 drm/mi0283qt: dtoverlay=watterott-display,drm,backlight-pwm,rotate=180
5023 Some notable differences with the DRM driver compared to fbtft:
5024 - The display is turned on when it's first used and not on driver load
5025 as with fbtft. So if nothing uses the display it stays off.
5026 - Can run with a higher SPI clock increasing framerate. This is possible
5027 since the driver avoids messing up the controller configuration due to
5028 transmission errors by running config commands at 10MHz and only pixel
5029 data at full speed (occasional pixel glitch might occur).
5030 - PWM backlight is supported.
5032 Load: dtoverlay=watterott-display,<param>=<val>
5033 Params: speed Display SPI bus speed
5034 rotate Display rotation {0,90,180,270}
5035 fps Delay between frame updates (fbtft only)
5036 debug Debug output level {0-7} (fbtft only)
5037 xohms Touchpanel sensitivity (X-plate resistance)
5038 swapxy Swap x and y axis
5039 backlight Change backlight GPIO pin {e.g. 12, 18}
5041 drm Use DRM/KMS driver mi0283qt instead of fbtft.
5042 Set the SPI clock to 70MHz.
5043 This has to be the first parameter.
5044 backlight-pwm Use pwm for backlight (drm only). NB: Disables
5045 audio headphone output as that also uses PWM.
5048 Name: waveshare-can-fd-hat-mode-a
5049 Info: Overlay for the Waveshare 2-Channel Isolated CAN FD Expansion HAT
5050 for Raspberry Pi, Multi Protections. Use this overlay when the
5051 HAT is configured in Mode A (Default), with can0 on spi0.0
5053 https://www.waveshare.com/2-ch-can-fd-hat.htm
5054 Load: dtoverlay=waveshare-can-fd-hat-mode-a
5058 Name: waveshare-can-fd-hat-mode-b
5059 Info: Overlay for the Waveshare 2-Channel Isolated CAN FD Expansion HAT
5060 for Raspberry Pi, Multi Protections. Use this overlay when the
5061 HAT is configured in Mode B (requires hardware modification), with
5062 can0 on spi0.0 and can1 on spi0.1.
5063 https://www.waveshare.com/2-ch-can-fd-hat.htm
5064 Load: dtoverlay=waveshare-can-fd-hat-mode-b
5069 Info: Configures the wittypi RTC module.
5070 Load: dtoverlay=wittypi,<param>=<val>
5071 Params: led_gpio GPIO for LED (default "17")
5072 led_trigger Choose which activity the LED tracks (default
5076 Name: wm8960-soundcard
5077 Info: Overlay for the Waveshare wm8960 soundcard
5078 Load: dtoverlay=wm8960-soundcard,<param>=<val>
5079 Params: alsaname Changes the card name in ALSA
5080 compatible Changes the codec compatibility
5086 If you are experiencing problems that you think are DT-related, enable DT
5087 diagnostic output by adding this to /boot/config.txt:
5091 and rebooting. Then run:
5095 and look for relevant messages.
5100 This is only meant to be a quick introduction to the subject of Device Tree on
5101 Raspberry Pi. There is a more complete explanation here:
5103 http://www.raspberrypi.org/documentation/configuration/device-tree.md
projects / platform / kernel / linux-rpi.git / blob