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 eee Enable Energy Efficient Ethernet support for
177 compatible devices (default "on"). See also
178 "tx_lpi_timer". Pi3B+ only.
180 eth_downshift_after Set the number of auto-negotiation failures
181 after which the 1000Mbps modes are disabled.
182 Legal values are 2, 3, 4, 5 and 0, where
183 0 means never downshift (default 2). Pi3B+ only.
185 eth_led0 Set mode of LED0 - amber on Pi3B+ (default "1"),
186 green on Pi4 (default "0").
187 The legal values are:
191 0=link/activity 1=link1000/activity
192 2=link100/activity 3=link10/activity
193 4=link100/1000/activity 5=link10/1000/activity
194 6=link10/100/activity 14=off 15=on
198 0=Speed/Activity 1=Speed
199 2=Flash activity 3=FDX
204 eth_led1 Set mode of LED1 - green on Pi3B+ (default "6"),
205 amber on Pi4 (default "8"). See eth_led0 for
208 eth_max_speed Set the maximum speed a link is allowed
209 to negotiate. Legal values are 10, 100 and
210 1000 (default 1000). Pi3B+ only.
212 hdmi Set to "off" to disable the HDMI interface
215 i2c An alias for i2c_arm
217 i2c_arm Set to "on" to enable the ARM's i2c interface
220 i2c_arm_baudrate Set the baudrate of the ARM's i2c interface
223 i2c_baudrate An alias for i2c_arm_baudrate
225 i2c_csi_dsi Set to "on" to enable the i2c_csi_dsi interface
227 i2c_csi_dsi0 Set to "on" to enable the i2c_csi_dsi0 interface
229 i2c_csi_dsi1 Set to "on" to enable the i2c_csi_dsi1 interface
231 i2c_vc Set to "on" to enable the i2c interface
232 usually reserved for the VideoCore processor
235 i2c_vc_baudrate Set the baudrate of the VideoCore i2c interface
238 i2s Set to "on" to enable the i2s interface
241 i2s_dma4 Use to enable 40-bit DMA on the i2s interface
242 (the assigned value doesn't matter)
245 krnbt Set to "off" to disable autoprobing of Bluetooth
246 driver without need of hciattach/btattach
249 krnbt_baudrate Set the baudrate of the PL011 UART when used
252 nvme Alias for "pciex1" (2712 only)
254 pcie Set to "off" to disable the PCIe interface
256 (2711 only, but not applicable on CM4S)
257 N.B. USB-A ports on 4B are subsequently disabled
259 pciex1 Set to "on" to enable the external PCIe link
260 (2712 only, default "off")
262 pciex1_gen Sets the PCIe "GEN"/speed for the external PCIe
263 link (2712 only, default "2")
265 pciex1_no_l0s Set to "on" to disable ASPM L0s on the external
266 PCIe link for devices that have broken
267 implementations (2712 only, default "off")
269 spi Set to "on" to enable the spi interfaces
272 spi_dma4 Use to enable 40-bit DMA on spi interfaces
273 (the assigned value doesn't matter)
276 random Set to "on" to enable the hardware random
277 number generator (default "on")
279 rtc_bbat_vchg Set the RTC backup battery charging voltage in
280 microvolts. If set to 0 or not specified, the
281 trickle charger is disabled.
282 (2712 only, default "0")
284 sd Set to "off" to disable the SD card (or eMMC on
285 non-lite SKU of CM4).
288 sd_overclock Clock (in MHz) to use when the MMC framework
291 sd_poll_once Looks for a card once after booting. Useful
292 for network booting scenarios to avoid the
293 overhead of continuous polling. N.B. Using
294 this option restricts the system to using a
295 single card per boot (or none at all).
298 sd_force_pio Disable DMA support for SD driver (default off)
300 sd_pio_limit Number of blocks above which to use DMA for
303 sd_debug Enable debug output from SD driver (default off)
305 sdio_overclock Clock (in MHz) to use when the MMC framework
306 requests 50MHz for the SDIO/WLAN interface.
308 suspend Make the power button trigger a suspend rather
309 than a power-off (2712 only, default "off")
311 tx_lpi_timer Set the delay in microseconds between going idle
312 and entering the low power state (default 600).
313 Requires EEE to be enabled - see "eee".
315 uart0 Set to "off" to disable uart0 (default "on")
317 uart0_console Move the kernel boot console to UART0 on pins
318 6, 8 and 10 of the 40-way header (2712 only,
321 uart1 Set to "on" or "off" to enable or disable uart1
324 watchdog Set to "on" to enable the hardware watchdog
327 wifiaddr Set an alternative WiFi MAC address.
328 The value should be a 6-byte hexadecimal value,
329 with or without colon separators, written in the
330 natural (big-endian) order.
332 act_led_trigger Choose which activity the LED tracks.
333 Use "heartbeat" for a nice load indicator.
336 act_led_activelow Set to "on" to invert the sense of the LED
338 N.B. For Pi 3B, 3B+, 3A+ and 4B, use the act-led
341 act_led_gpio Set which GPIO to use for the activity LED
342 (in case you want to connect it to an external
344 (default "16" on a non-Plus board, "47" on a
346 N.B. For Pi 3B, 3B+, 3A+ and 4B, use the act-led
352 As for act_led_*, but using the PWR LED.
353 Not available on Model A/B boards.
355 N.B. It is recommended to only enable those interfaces that are needed.
356 Leaving all interfaces enabled can lead to unwanted behaviour (i2c_vc
357 interfering with Pi Camera, I2S and SPI hogging GPIO pins, etc.)
358 Note also that i2c, i2c_arm and i2c_vc are aliases for the physical
359 interfaces i2c0 and i2c1. Use of the numeric variants is still possible
360 but deprecated because the ARM/VC assignments differ between board
361 revisions. The same board-specific mapping applies to i2c_baudrate,
362 and the other i2c baudrate parameters.
366 Info: Pi 3B, 3B+, 3A+ and 4B use a GPIO expander to drive the LEDs which can
367 only be accessed from the VPU. There is a special driver for this with a
368 separate DT node, which has the unfortunate consequence of breaking the
369 act_led_gpio and act_led_activelow dtparams.
370 This overlay changes the GPIO controller back to the standard one and
371 restores the dtparams.
372 Load: dtoverlay=act-led,<param>=<val>
373 Params: activelow Set to "on" to invert the sense of the LED
376 gpio Set which GPIO to use for the activity LED
377 (in case you want to connect it to an external
382 Name: adafruit-st7735r
383 Info: Overlay for the SPI-connected Adafruit 1.8" 160x128 or 128x128 displays,
384 based on the ST7735R chip.
385 This overlay uses the newer DRM/KMS "Tiny" driver.
386 Load: dtoverlay=adafruit-st7735r,<param>=<val>
387 Params: 128x128 Select the 128x128 driver (default 160x128)
388 rotate Display rotation {0,90,180,270} (default 90)
389 speed SPI bus speed in Hz (default 4000000)
390 dc_pin GPIO pin for D/C (default 24)
391 reset_pin GPIO pin for RESET (default 25)
392 led_pin GPIO used to control backlight (default 18)
396 Info: Overlay for the SPI-connected Adafruit 1.8" display (based on the
397 ST7735R chip). It includes support for the "green tab" version.
398 This overlay uses the older fbtft driver.
399 Load: dtoverlay=adafruit18,<param>=<val>
400 Params: green Use the adafruit18_green variant.
401 rotate Display rotation {0,90,180,270}
402 speed SPI bus speed in Hz (default 4000000)
403 fps Display frame rate in Hz
404 bgr Enable BGR mode (default off)
405 debug Debug output level {0-7}
406 dc_pin GPIO pin for D/C (default 24)
407 reset_pin GPIO pin for RESET (default 25)
408 led_pin GPIO used to control backlight (default 18)
412 Info: Overlay for activation of ADAU1977 ADC codec over I2C for control
414 Load: dtoverlay=adau1977-adc
418 Name: adau7002-simple
419 Info: Overlay for the activation of ADAU7002 stereo PDM to I2S converter.
420 Load: dtoverlay=adau7002-simple,<param>=<val>
421 Params: card-name Override the default, "adau7002", card name.
425 Info: Overlay for activation of Texas Instruments ADS1015 ADC over I2C
426 Load: dtoverlay=ads1015,<param>=<val>
427 Params: addr I2C bus address of device. Set based on how the
428 addr pin is wired. (default=0x48 assumes addr
430 cha_enable Enable virtual channel a. (default=true)
431 cha_cfg Set the configuration for virtual channel a.
432 (default=4 configures this channel for the
433 voltage at A0 with respect to GND)
434 cha_datarate Set the datarate (samples/sec) for this channel.
435 (default=4 sets 1600 sps)
436 cha_gain Set the gain of the Programmable Gain
437 Amplifier for this channel. (default=2 sets the
438 full scale of the channel to 2.048 Volts)
440 Channel (ch) parameters can be set for each enabled channel.
441 A maximum of 4 channels can be enabled (letters a thru d).
442 For more information refer to the device datasheet at:
443 http://www.ti.com/lit/ds/symlink/ads1015.pdf
447 Info: Texas Instruments ADS1115 ADC
448 Load: dtoverlay=ads1115,<param>[=<val>]
449 Params: addr I2C bus address of device. Set based on how the
450 addr pin is wired. (default=0x48 assumes addr
452 cha_enable Enable virtual channel a.
453 cha_cfg Set the configuration for virtual channel a.
454 (default=4 configures this channel for the
455 voltage at A0 with respect to GND)
456 cha_datarate Set the datarate (samples/sec) for this channel.
457 (default=7 sets 860 sps)
458 cha_gain Set the gain of the Programmable Gain
459 Amplifier for this channel. (Default 1 sets the
460 full scale of the channel to 4.096 Volts)
462 Channel parameters can be set for each enabled channel.
463 A maximum of 4 channels can be enabled (letters a thru d).
464 For more information refer to the device datasheet at:
465 http://www.ti.com/lit/ds/symlink/ads1115.pdf
469 Info: ADS7846 Touch controller
470 Load: dtoverlay=ads7846,<param>=<val>
471 Params: cs SPI bus Chip Select (default 1)
472 speed SPI bus speed (default 2MHz, max 3.25MHz)
473 penirq GPIO used for PENIRQ. REQUIRED
474 penirq_pull Set GPIO pull (default 0=none, 2=pullup)
475 swapxy Swap x and y axis
476 xmin Minimum value on the X axis (default 0)
477 ymin Minimum value on the Y axis (default 0)
478 xmax Maximum value on the X axis (default 4095)
479 ymax Maximum value on the Y axis (default 4095)
480 pmin Minimum reported pressure value (default 0)
481 pmax Maximum reported pressure value (default 65535)
482 xohms Touchpanel sensitivity (X-plate resistance)
485 penirq is required and usually xohms (60-100) has to be set as well.
486 Apart from that, pmax (255) and swapxy are also common.
487 The rest of the calibration can be done with xinput-calibrator.
488 See: github.com/notro/fbtft/wiki/FBTFT-on-Raspian
489 Device Tree binding document:
490 www.kernel.org/doc/Documentation/devicetree/bindings/input/ads7846.txt
494 Info: Analog Devices ADV7282M analogue video to CSI2 bridge.
495 Uses Unicam1, which is the standard camera connector on most Pi
497 Load: dtoverlay=adv7282m,<param>=<val>
498 Params: addr Overrides the I2C address (default 0x21)
499 media-controller Configure use of Media Controller API for
500 configuring the sensor (default off)
504 Info: Analog Devices ADV728[0|1|2]-M analogue video to CSI2 bridges.
505 This is a wrapper for adv7282m, and defaults to ADV7282M.
506 Load: dtoverlay=adv728x-m,<param>=<val>
507 Params: addr Overrides the I2C address (default 0x21)
508 adv7280m Select ADV7280-M.
509 adv7281m Select ADV7281-M.
510 adv7281ma Select ADV7281-MA.
511 media-controller Configure use of Media Controller API for
512 configuring the sensor (default off)
515 Name: akkordion-iqdacplus
516 Info: Configures the Digital Dreamtime Akkordion Music Player (based on the
517 OEM IQAudIO DAC+ or DAC Zero module).
518 Load: dtoverlay=akkordion-iqdacplus,<param>=<val>
519 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
520 Digital volume control. Enable with
521 dtoverlay=akkordion-iqdacplus,24db_digital_gain
522 (The default behaviour is that the Digital
523 volume control is limited to a maximum of
524 0dB. ie. it can attenuate but not provide
525 gain. For most users, this will be desired
526 as it will prevent clipping. By appending
527 the 24db_digital_gain parameter, the Digital
528 volume control will allow up to 24dB of
529 gain. If this parameter is enabled, it is the
530 responsibility of the user to ensure that
531 the Digital volume control is set to a value
532 that does not result in clipping/distortion!)
535 Name: allo-boss-dac-pcm512x-audio
536 Info: Configures the Allo Boss DAC audio cards.
537 Load: dtoverlay=allo-boss-dac-pcm512x-audio,<param>
538 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
539 Digital volume control. Enable with
540 "dtoverlay=allo-boss-dac-pcm512x-audio,
542 (The default behaviour is that the Digital
543 volume control is limited to a maximum of
544 0dB. ie. it can attenuate but not provide
545 gain. For most users, this will be desired
546 as it will prevent clipping. By appending
547 the 24db_digital_gain parameter, the Digital
548 volume control will allow up to 24dB of
549 gain. If this parameter is enabled, it is the
550 responsibility of the user to ensure that
551 the Digital volume control is set to a value
552 that does not result in clipping/distortion!)
553 slave Force Boss DAC into slave mode, using Pi a
554 master for bit clock and frame clock. Enable
555 with "dtoverlay=allo-boss-dac-pcm512x-audio,
559 Name: allo-boss2-dac-audio
560 Info: Configures the Allo Boss2 DAC audio card
561 Load: dtoverlay=allo-boss2-dac-audio
566 Info: Configures the Allo Digione audio card
567 Load: dtoverlay=allo-digione
571 Name: allo-katana-dac-audio
572 Info: Configures the Allo Katana DAC audio card
573 Load: dtoverlay=allo-katana-dac-audio
577 Name: allo-piano-dac-pcm512x-audio
578 Info: Configures the Allo Piano DAC (2.0/2.1) audio cards.
579 (NB. This initial support is for 2.0 channel audio ONLY! ie. stereo.
580 The subwoofer outputs on the Piano 2.1 are not currently supported!)
581 Load: dtoverlay=allo-piano-dac-pcm512x-audio,<param>
582 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
583 Digital volume control.
584 (The default behaviour is that the Digital
585 volume control is limited to a maximum of
586 0dB. ie. it can attenuate but not provide
587 gain. For most users, this will be desired
588 as it will prevent clipping. By appending
589 the 24db_digital_gain parameter, the Digital
590 volume control will allow up to 24dB of
591 gain. If this parameter is enabled, it is the
592 responsibility of the user to ensure that
593 the Digital volume control is set to a value
594 that does not result in clipping/distortion!)
597 Name: allo-piano-dac-plus-pcm512x-audio
598 Info: Configures the Allo Piano DAC (2.1) audio cards.
599 Load: dtoverlay=allo-piano-dac-plus-pcm512x-audio,<param>
600 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
601 Digital volume control.
602 (The default behaviour is that the Digital
603 volume control is limited to a maximum of
604 0dB. ie. it can attenuate but not provide
605 gain. For most users, this will be desired
606 as it will prevent clipping. By appending
607 the 24db_digital_gain parameter, the Digital
608 volume control will allow up to 24dB of
609 gain. If this parameter is enabled, it is the
610 responsibility of the user to ensure that
611 the Digital volume control is set to a value
612 that does not result in clipping/distortion!)
613 glb_mclk This option is only with Kali board. If enabled,
614 MCLK for Kali is used and PLL is disabled for
615 better voice quality. (default Off)
619 Info: Universal device tree overlay for SPI devices
621 Just specify the SPI address and device name ("compatible" property).
622 This overlay lacks any device-specific parameter support!
624 For devices on spi1 or spi2, the interfaces should be enabled
625 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
628 1. SPI NOR flash on spi0.1, maximum SPI clock frequency 45MHz:
629 dtoverlay=anyspi:spi0-1,dev="jedec,spi-nor",speed=45000000
630 2. MCP3204 ADC on spi1.2, maximum SPI clock frequency 500kHz:
631 dtoverlay=anyspi:spi1-2,dev="microchip,mcp3204"
632 Load: dtoverlay=anyspi,<param>=<val>
633 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
635 dev Set device name to search compatible module
637 speed Set SPI clock frequency in Hz
638 (integer, optional, default 500000)
642 Info: Configures the AVAGO APDS9960 digital proximity, ambient light, RGB and
644 Load: dtoverlay=apds9960,<param>=<val>
645 Params: gpiopin GPIO used for INT (default 4)
646 noints Disable the interrupt GPIO line.
650 Info: Configures the Orchard Audio ApplePi-DAC audio card
651 Load: dtoverlay=applepi-dac
656 Info: Arducam 64MP camera module.
657 Uses Unicam 1, which is the standard camera connector on most Pi
659 Load: dtoverlay=arducam-64mp,<param>=<val>
660 Params: rotation Mounting rotation of the camera sensor (0 or
662 orientation Sensor orientation (0 = front, 1 = rear,
663 2 = external, default external)
664 media-controller Configure use of Media Controller API for
665 configuring the sensor (default on)
666 cam0 Adopt the default configuration for CAM0 on a
667 Compute Module (CSI0, i2c_vc, and cam0_reg).
668 vcm Select lens driver state. Default is enabled,
669 but vcm=off will disable.
672 Name: arducam-pivariety
673 Info: Arducam Pivariety camera module.
674 Uses Unicam 1, which is the standard camera connector on most Pi
676 Load: dtoverlay=arducam-pivariety,<param>=<val>
677 Params: rotation Mounting rotation of the camera sensor (0 or
679 orientation Sensor orientation (0 = front, 1 = rear,
680 2 = external, default external)
681 media-controller Configure use of Media Controller API for
682 configuring the sensor (default on)
683 cam0 Adopt the default configuration for CAM0 on a
684 Compute Module (CSI0, i2c_vc, and cam0_reg).
688 Info: Configures the Atmel AT86RF233 802.15.4 low-power WPAN transceiver,
690 Load: dtoverlay=at86rf233,<param>=<val>
691 Params: interrupt GPIO used for INT (default 23)
692 reset GPIO used for Reset (default 24)
693 sleep GPIO used for Sleep (default 25)
694 speed SPI bus speed in Hz (default 3000000)
695 trim Fine tuning of the internal capacitance
696 arrays (0=+0pF, 15=+4.5pF, default 15)
699 Name: audioinjector-addons
700 Info: Configures the audioinjector.net audio add on soundcards
701 Load: dtoverlay=audioinjector-addons,<param>=<val>
702 Params: non-stop-clocks Keeps the clocks running even when the stream
703 is paused or stopped (default off)
706 Name: audioinjector-bare-i2s
707 Info: Configures the audioinjector.net audio bare i2s soundcard
708 Load: dtoverlay=audioinjector-bare-i2s
712 Name: audioinjector-isolated-soundcard
713 Info: Configures the audioinjector.net isolated soundcard
714 Load: dtoverlay=audioinjector-isolated-soundcard
718 Name: audioinjector-ultra
719 Info: Configures the audioinjector.net ultra soundcard
720 Load: dtoverlay=audioinjector-ultra
724 Name: audioinjector-wm8731-audio
725 Info: Configures the audioinjector.net audio add on soundcard
726 Load: dtoverlay=audioinjector-wm8731-audio
731 Info: Configures the audiosense-pi add on soundcard
732 For more information refer to
733 https://gitlab.com/kakar0t/audiosense-pi
734 Load: dtoverlay=audiosense-pi
739 Info: Switches PWM sound output to GPIOs on the 40-pin header
740 Load: dtoverlay=audremap,<param>=<val>
741 Params: swap_lr Reverse the channel allocation, which will also
742 swap the audio jack outputs (default off)
743 enable_jack Don't switch off the audio jack output. Does
744 nothing on BCM2711 (default off)
745 pins_12_13 Select GPIOs 12 & 13 (default)
746 pins_18_19 Select GPIOs 18 & 19
747 pins_40_41 Select GPIOs 40 & 41 (not available on CM4, used
749 pins_40_45 Select GPIOs 40 & 45 (don't use on BCM2711 - the
750 pins are on different controllers)
754 Info: Overlay that enables WLAN, Bluetooth and the GPIO expander on the
755 balenaFin carrier board for the Raspberry Pi Compute Module 3/3+ Lite.
756 Load: dtoverlay=balena-fin
760 Name: bmp085_i2c-sensor
761 Info: This overlay is now deprecated - see i2c-sensor
765 Name: camera-mux-2port
766 Info: Configures a 2 port camera multiplexer
767 Note that currently ALL IMX290 modules share a common clock, therefore
768 all modules will need to have the same clock frequency.
769 Load: dtoverlay=camera-mux-2port,<param>=<val>
770 Params: cam0-arducam-64mp Select Arducam64MP for camera on port 0
771 cam0-imx219 Select IMX219 for camera on port 0
772 cam0-imx258 Select IMX258 for camera on port 0
773 cam0-imx290 Select IMX290 for camera on port 0
774 cam0-imx477 Select IMX477 for camera on port 0
775 cam0-imx519 Select IMX519 for camera on port 0
776 cam0-imx708 Select IMX708 for camera on port 0
777 cam0-ov2311 Select OV2311 for camera on port 0
778 cam0-ov5647 Select OV5647 for camera on port 0
779 cam0-ov7251 Select OV7251 for camera on port 0
780 cam0-ov9281 Select OV9281 for camera on port 0
781 cam0-imx290-clk-freq Set clock frequency for an IMX290 on port 0
782 cam1-arducam-64mp Select Arducam64MP for camera on port 1
783 cam1-imx219 Select IMX219 for camera on port 1
784 cam1-imx258 Select IMX258 for camera on port 1
785 cam1-imx290 Select IMX290 for camera on port 1
786 cam1-imx477 Select IMX477 for camera on port 1
787 cam1-imx519 Select IMX519 for camera on port 1
788 cam1-imx708 Select IMX708 for camera on port 1
789 cam1-ov2311 Select OV2311 for camera on port 1
790 cam1-ov5647 Select OV5647 for camera on port 1
791 cam1-ov7251 Select OV7251 for camera on port 1
792 cam1-ov9281 Select OV9281 for camera on port 1
793 cam1-imx290-clk-freq Set clock frequency for an IMX290 on port 1
796 Name: camera-mux-4port
797 Info: Configures a 4 port camera multiplexer
798 Note that currently ALL IMX290 modules share a common clock, therefore
799 all modules will need to have the same clock frequency.
800 Load: dtoverlay=camera-mux-4port,<param>=<val>
801 Params: cam0-arducam-64mp Select Arducam64MP for camera on port 0
802 cam0-imx219 Select IMX219 for camera on port 0
803 cam0-imx258 Select IMX258 for camera on port 0
804 cam0-imx290 Select IMX290 for camera on port 0
805 cam0-imx477 Select IMX477 for camera on port 0
806 cam0-imx519 Select IMX519 for camera on port 0
807 cam0-imx708 Select IMX708 for camera on port 0
808 cam0-ov2311 Select OV2311 for camera on port 0
809 cam0-ov5647 Select OV5647 for camera on port 0
810 cam0-ov7251 Select OV7251 for camera on port 0
811 cam0-ov9281 Select OV9281 for camera on port 0
812 cam0-imx290-clk-freq Set clock frequency for an IMX290 on port 0
813 cam1-arducam-64mp Select Arducam64MP for camera on port 1
814 cam1-imx219 Select IMX219 for camera on port 1
815 cam1-imx258 Select IMX258 for camera on port 1
816 cam1-imx290 Select IMX290 for camera on port 1
817 cam1-imx477 Select IMX477 for camera on port 1
818 cam1-imx519 Select IMX519 for camera on port 1
819 cam1-imx708 Select IMX708 for camera on port 1
820 cam1-ov2311 Select OV2311 for camera on port 1
821 cam1-ov5647 Select OV5647 for camera on port 1
822 cam1-ov7251 Select OV7251 for camera on port 1
823 cam1-ov9281 Select OV9281 for camera on port 1
824 cam1-imx290-clk-freq Set clock frequency for an IMX290 on port 1
825 cam2-arducam-64mp Select Arducam64MP for camera on port 2
826 cam2-imx219 Select IMX219 for camera on port 2
827 cam2-imx258 Select IMX258 for camera on port 2
828 cam2-imx290 Select IMX290 for camera on port 2
829 cam2-imx477 Select IMX477 for camera on port 2
830 cam2-imx519 Select IMX519 for camera on port 2
831 cam2-imx708 Select IMX708 for camera on port 2
832 cam2-ov2311 Select OV2311 for camera on port 2
833 cam2-ov5647 Select OV5647 for camera on port 2
834 cam2-ov7251 Select OV7251 for camera on port 2
835 cam2-ov9281 Select OV9281 for camera on port 2
836 cam2-imx290-clk-freq Set clock frequency for an IMX290 on port 2
837 cam3-arducam-64mp Select Arducam64MP for camera on port 3
838 cam3-imx219 Select IMX219 for camera on port 3
839 cam3-imx258 Select IMX258 for camera on port 3
840 cam3-imx290 Select IMX290 for camera on port 3
841 cam3-imx477 Select IMX477 for camera on port 3
842 cam3-imx519 Select IMX519 for camera on port 3
843 cam3-imx708 Select IMX708 for camera on port 3
844 cam3-ov2311 Select OV2311 for camera on port 3
845 cam3-ov5647 Select OV5647 for camera on port 3
846 cam3-ov7251 Select OV7251 for camera on port 3
847 cam3-ov9281 Select OV9281 for camera on port 3
848 cam3-imx290-clk-freq Set clock frequency for an IMX290 on port 3
852 Info: Enables the ability to use the cap1106 touch sensor as a keyboard
853 Load: dtoverlay=cap1106,<param>=<val>
854 Params: int_pin GPIO pin for interrupt signal (default 23)
858 Info: Configures Chip Dip audio cards.
859 Load: dtoverlay=chipdip-dac
864 Info: Configures the Cirrus Logic Audio Card
865 Load: dtoverlay=cirrus-wm5102
870 Info: Largely for Compute Modules 1&3 where the original instructions for
871 adding a camera used GPIOs 0&1 for CAM1 and 28&29 for CAM0, whilst all
872 other platforms use 28&29 (or 44&45) for CAM1.
873 The default assignment through using this overlay is for
874 i2c0 to use 28&29, and i2c10 (aka i2c_csi_dsi) to use 28&29, but the
875 overrides allow this to be changed.
876 Load: dtoverlay=cm-swap-i2c0,<param>=<val>
877 Params: i2c0-gpio0 Use GPIOs 0&1 for i2c0
878 i2c0-gpio28 Use GPIOs 28&29 for i2c0 (default)
879 i2c0-gpio44 Use GPIOs 44&45 for i2c0
880 i2c10-gpio0 Use GPIOs 0&1 for i2c0 (default)
881 i2c10-gpio28 Use GPIOs 28&29 for i2c0
882 i2c10-gpio44 Use GPIOs 44&45 for i2c0
886 Info: Set custom CMA sizes, only use if you know what you are doing, might
887 clash with other overlays like vc4-fkms-v3d and vc4-kms-v3d.
888 Load: dtoverlay=cma,<param>=<val>
889 Params: cma-512 CMA is 512MB (needs 1GB)
890 cma-448 CMA is 448MB (needs 1GB)
891 cma-384 CMA is 384MB (needs 1GB)
892 cma-320 CMA is 320MB (needs 1GB)
893 cma-256 CMA is 256MB (needs 1GB)
894 cma-192 CMA is 192MB (needs 1GB)
898 cma-size CMA size in bytes, 4MB aligned
899 cma-default Use upstream's default value
902 Name: crystalfontz-cfa050_pi_m
903 Info: Configures the Crystalfontz CFA050-PI-M series of Raspberry Pi CM4
904 based modules using the CFA7201280A0_050Tx 7" TFT LCD displays,
905 with or without capacitive touch screen.
906 Requires use of vc4-kms-v3d.
907 Load: dtoverlay=crystalfontz-cfa050_pi_m,<param>=<val>
908 Params: captouch Enable capacitive touch display
912 Info: 8" TFT LCD display and touch panel used by cutiepi.io
913 Load: dtoverlay=cutiepi-panel
918 Info: Configures the dacberry400 add on soundcard
919 Load: dtoverlay=dacberry400
924 Info: Overlay for the DHT11/DHT21/DHT22 humidity/temperature sensors
925 Also sometimes found with the part number(s) AM230x.
926 Load: dtoverlay=dht11,<param>=<val>
927 Params: gpiopin GPIO connected to the sensor's DATA output.
932 Info: Configures the Dion Audio KIWI STREAMER
933 Load: dtoverlay=dionaudio-kiwi
938 Info: Configures the Dion Audio LOCO DAC-AMP
939 Load: dtoverlay=dionaudio-loco
943 Name: dionaudio-loco-v2
944 Info: Configures the Dion Audio LOCO-V2 DAC-AMP
945 Load: dtoverlay=dionaudio-loco-v2,<param>=<val>
946 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
947 Digital volume control. Enable with
948 "dtoverlay=hifiberry-dacplus,24db_digital_gain"
949 (The default behaviour is that the Digital
950 volume control is limited to a maximum of
951 0dB. ie. it can attenuate but not provide
952 gain. For most users, this will be desired
953 as it will prevent clipping. By appending
954 the 24dB_digital_gain parameter, the Digital
955 volume control will allow up to 24dB of
956 gain. If this parameter is enabled, it is the
957 responsibility of the user to ensure that
958 the Digital volume control is set to a value
959 that does not result in clipping/distortion!)
963 Info: Disable onboard Bluetooth on Bluetooth-capable Raspberry Pis. On Pis
964 prior to Pi 5 this restores UART0/ttyAMA0 over GPIOs 14 & 15.
965 Load: dtoverlay=disable-bt
974 Info: Disable EMMC2 controller on BCM2711.
975 The allows the onboard EMMC storage on Compute Module 4 to be disabled
976 e.g. if a fault has occurred.
977 Load: dtoverlay=disable-emmc2
982 Info: Disable onboard WLAN on WiFi-capable Raspberry Pis.
983 Load: dtoverlay=disable-wifi
987 Name: disable-wifi-pi5
988 Info: See disable-wifi
992 Info: Overlay for a generic 18-bit DPI display
993 This uses GPIOs 0-21 (so no I2C, uart etc.), and activates the output
994 2-3 seconds after the kernel has started.
995 Load: dtoverlay=dpi18
1000 Info: Overlay for a generic 18-bit DPI display (in 'mode 6' connection scheme)
1001 This uses GPIOs 0-9,12-17,20-25 (so no I2C, uart etc.), and activates
1002 the output 3-3 seconds after the kernel has started.
1003 Load: dtoverlay=dpi18cpadhi
1008 Info: Overlay for a generic 24-bit DPI display
1009 This uses GPIOs 0-27 (so no I2C, uart etc.), and activates the output
1010 2-3 seconds after the kernel has started.
1011 Load: dtoverlay=dpi24
1016 Info: Configures the NW Digital Radio DRAWS Hat
1018 The board includes an ADC to measure various board values and also
1019 provides two analog user inputs on the expansion header. The ADC
1020 can be configured for various sample rates and gain values to adjust
1021 the input range. Tables describing the two parameters follow.
1033 ADC Datarate Values:
1038 4 = 1600sps (default)
1042 Load: dtoverlay=draws,<param>=<val>
1043 Params: draws_adc_ch4_gain Sets the full scale resolution of the ADCs
1044 input voltage sensor (default 1)
1046 draws_adc_ch4_datarate Sets the datarate of the ADCs input voltage
1049 draws_adc_ch5_gain Sets the full scale resolution of the ADCs
1050 5V rail voltage sensor (default 1)
1052 draws_adc_ch5_datarate Sets the datarate of the ADCs 4V rail voltage
1055 draws_adc_ch6_gain Sets the full scale resolution of the ADCs
1056 AIN2 input (default 2)
1058 draws_adc_ch6_datarate Sets the datarate of the ADCs AIN2 input
1060 draws_adc_ch7_gain Sets the full scale resolution of the ADCs
1061 AIN3 input (default 2)
1063 draws_adc_ch7_datarate Sets the datarate of the ADCs AIN3 input
1065 alsaname Name of the ALSA audio device (default "draws")
1069 Info: Selects the dwc_otg USB controller driver which has fiq support. This
1070 is the default on all except the Pi Zero which defaults to dwc2.
1071 Load: dtoverlay=dwc-otg
1076 Info: Selects the dwc2 USB controller driver
1077 Load: dtoverlay=dwc2,<param>=<val>
1078 Params: dr_mode Dual role mode: "host", "peripheral" or "otg"
1080 g-rx-fifo-size Size of rx fifo size in gadget mode
1082 g-np-tx-fifo-size Size of non-periodic tx fifo size in gadget
1086 [ The ds1307-rtc overlay has been deleted. See i2c-rtc. ]
1090 Info: Overlay for the EDT FT5406 touchscreen.
1091 This works with the Raspberry Pi 7" touchscreen when not being polled
1093 By default the overlay uses the i2c_csi_dsi I2C interface, but this
1095 You MUST use either "disable_touchscreen=1" or "ignore_lcd=1" in
1096 config.txt to stop the firmware polling the touchscreen.
1097 Load: dtoverlay=edt-ft5406,<param>=<val>
1098 Params: sizex Touchscreen size x (default 800)
1099 sizey Touchscreen size y (default 480)
1100 invx Touchscreen inverted x axis
1101 invy Touchscreen inverted y axis
1102 swapxy Touchscreen swapped x y axis
1103 i2c0 Choose the I2C0 bus on GPIOs 0&1
1104 i2c1 Choose the I2C1 bus on GPIOs 2&3
1105 i2c3 Choose the I2C3 bus (configure with the i2c3
1106 overlay - BCM2711 only)
1107 i2c4 Choose the I2C4 bus (configure with the i2c4
1108 overlay - BCM2711 only)
1109 i2c5 Choose the I2C5 bus (configure with the i2c5
1110 overlay - BCM2711 only)
1111 i2c6 Choose the I2C6 bus (configure with the i2c6
1112 overlay - BCM2711 only)
1113 addr Sets the address for the touch controller. Note
1114 that the device must be configured to use the
1119 Info: Overlay for the Microchip ENC28J60 Ethernet Controller on SPI0
1120 Load: dtoverlay=enc28j60,<param>=<val>
1121 Params: int_pin GPIO used for INT (default 25)
1123 speed SPI bus speed (default 12000000)
1127 Info: Overlay for the Microchip ENC28J60 Ethernet Controller on SPI2
1128 Load: dtoverlay=enc28j60-spi2,<param>=<val>
1129 Params: int_pin GPIO used for INT (default 39)
1131 speed SPI bus speed (default 12000000)
1135 Info: Enables I2C connected EETI EXC3000 multiple touch controller using
1136 GPIO 4 (pin 7 on GPIO header) for interrupt.
1137 Load: dtoverlay=exc3000,<param>=<val>
1138 Params: interrupt GPIO used for interrupt (default 4)
1139 sizex Touchscreen size x (default 4096)
1140 sizey Touchscreen size y (default 4096)
1141 invx Touchscreen inverted x axis
1142 invy Touchscreen inverted y axis
1143 swapxy Touchscreen swapped x y axis
1147 Info: Overlay for SPI-connected displays using the fbtft drivers.
1149 This overlay seeks to replace the functionality provided by fbtft_device
1150 which is now gone from the kernel.
1152 Most displays from fbtft_device have been ported over.
1154 dtoverlay=fbtft,spi0-0,rpi-display,reset_pin=23,dc_pin=24,led_pin=18,rotate=270
1156 It is also possible to specify the controller (this will use the default
1157 init sequence in the driver).
1159 dtoverlay=fbtft,spi0-0,ili9341,bgr,reset_pin=23,dc_pin=24,led_pin=18,rotate=270
1161 For devices on spi1 or spi2, the interfaces should be enabled
1162 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
1164 The following features of fbtft_device have not been ported over:
1165 - parallel bus is not supported
1166 - the init property which overrides the controller initialization
1167 sequence is not supported as a parameter due to memory limitations in
1168 the bootloader responsible for applying the overlay.
1170 See https://github.com/notro/fbtft/wiki/FBTFT-RPI-overlays for how to
1173 Load: dtoverlay=fbtft,<param>=<val>
1175 spi<n>-<m> Configure device at spi<n>, cs<m>
1177 speed SPI bus speed in Hz (default 32000000)
1178 cpha Shifted clock phase (CPHA) mode
1179 cpol Inverse clock polarity (CPOL) mode
1181 adafruit18 Adafruit 1.8
1182 adafruit22 Adafruit 2.2 (old)
1183 adafruit22a Adafruit 2.2
1184 adafruit28 Adafruit 2.8
1185 adafruit13m Adafruit 1.3 OLED
1186 admatec_c-berry28 C-Berry28
1188 er_tftm050_2 ER-TFTM070-2
1189 er_tftm070_5 ER-TFTM070-5
1191 ew24ha0_9bit EW24HA0 in 9-bit mode
1192 freetronicsoled128 Freetronics OLED128
1195 itdb28_spi ITDB02-2.8 with SPI interface circuit
1196 mi0283qt-2 Watterott MI0283QT-2
1197 mi0283qt-9a Watterott MI0283QT-9A
1198 nokia3310 Nokia 3310
1199 nokia3310a Nokia 3310a
1200 nokia5110 Nokia 5110
1202 pitft Adafruit PiTFT 2.8
1204 rpi-display Watterott rpi-display
1205 sainsmart18 Sainsmart 1.8
1206 sainsmart32_spi Sainsmart 3.2 with SPI interfce circuit
1207 tinylcd35 TinyLCD 3.5
1208 tm022hdh26 Tianma TM022HDH26
1209 tontec35_9481 Tontect 3.5 with ILI9481 controller
1210 tontec35_9486 Tontect 3.5 with ILI9486 controller
1211 waveshare32b Waveshare 3.2
1212 waveshare22 Waveshare 2.2
1214 bd663474 BD663474 display controller
1215 hx8340bn HX8340BN display controller
1216 hx8347d HX8347D display controller
1217 hx8353d HX8353D display controller
1218 hx8357d HX8357D display controller
1219 ili9163 ILI9163 display controller
1220 ili9320 ILI9320 display controller
1221 ili9325 ILI9325 display controller
1222 ili9340 ILI9340 display controller
1223 ili9341 ILI9341 display controller
1224 ili9481 ILI9481 display controller
1225 ili9486 ILI9486 display controller
1226 pcd8544 PCD8544 display controller
1227 ra8875 RA8875 display controller
1228 s6d02a1 S6D02A1 display controller
1229 s6d1121 S6D1121 display controller
1230 seps525 SEPS525 display controller
1231 sh1106 SH1106 display controller
1232 ssd1289 SSD1289 display controller
1233 ssd1305 SSD1305 display controller
1234 ssd1306 SSD1306 display controller
1235 ssd1325 SSD1325 display controller
1236 ssd1331 SSD1331 display controller
1237 ssd1351 SSD1351 display controller
1238 st7735r ST7735R display controller
1239 st7789v ST7789V display controller
1240 tls8204 TLS8204 display controller
1241 uc1611 UC1611 display controller
1242 uc1701 UC1701 display controller
1243 upd161704 UPD161704 display controller
1245 width Display width in pixels
1246 height Display height in pixels
1247 regwidth Display controller register width (default is
1249 buswidth Display bus interface width (default 8)
1250 debug Debug output level {0-7}
1251 rotate Display rotation {0, 90, 180, 270} (counter
1252 clockwise). Not supported by all drivers.
1253 bgr Enable BGR mode (default off). Use if Red and
1254 Blue are swapped. Not supported by all drivers.
1255 fps Frames per second (default 30). In effect this
1256 states how long the driver will wait after video
1257 memory has been changed until display update
1258 transfer is started.
1259 txbuflen Length of the FBTFT transmit buffer
1261 startbyte Sets the Start byte used by fb_ili9320,
1262 fb_ili9325 and fb_hx8347d. Common value is 0x70.
1263 gamma String representation of Gamma Curve(s). Driver
1264 specific. Not supported by all drivers.
1265 reset_pin GPIO pin for RESET
1266 dc_pin GPIO pin for D/C
1267 led_pin GPIO pin for LED backlight
1271 Info: Configures the Fe-Pi Audio Sound Card
1272 Load: dtoverlay=fe-pi-audio
1277 Info: A demonstration of the gpio-fsm driver. The GPIOs are chosen to work
1278 nicely with a "traffic-light" display of red, amber and green LEDs on
1279 GPIOs 7, 8 and 25 respectively.
1280 Load: dtoverlay=fsm-demo,<param>=<val>
1281 Params: fsm_debug Enable debug logging (default off)
1285 Info: Enables GalaxyCore's GC9A01 single chip driver based displays on
1286 SPI0 as fb1, using GPIOs DC=25, RST=27 and BL=18 (physical
1287 GPIO header pins 22, 13 and 12 respectively) in addition to the
1288 SPI0 pins DIN=10, CLK=11 and CS=8 (physical GPIO header pins 19,
1289 23 and 24 respectively).
1290 Load: dtoverlay=gc9a01,<param>=<val>
1291 Params: speed Display SPI bus speed
1293 rotate Display rotation {0,90,180,270}
1295 width Width of the display
1297 height Height of the display
1299 fps Delay between frame updates
1301 debug Debug output level {0-7}
1305 Info: An overlay for the Ghost amplifier.
1306 Load: dtoverlay=ghost-amp,<param>=<val>
1307 Params: fsm_debug Enable debug logging of the GPIO FSM (default
1312 Info: Enables I2C connected Goodix gt9271 multiple touch controller using
1313 GPIOs 4 and 17 (pins 7 and 11 on GPIO header) for interrupt and reset.
1314 Load: dtoverlay=goodix,<param>=<val>
1315 Params: interrupt GPIO used for interrupt (default 4)
1316 reset GPIO used for reset (default 17)
1319 Name: googlevoicehat-soundcard
1320 Info: Configures the Google voiceHAT soundcard
1321 Load: dtoverlay=googlevoicehat-soundcard
1326 Info: This is a generic overlay for detecting charger with GPIO.
1327 Load: dtoverlay=gpio-charger,<param>=<val>
1328 Params: gpio GPIO pin to trigger on (default 4)
1329 active_low When this is 1 (active low), a falling
1330 edge generates a charging event and a
1331 rising edge generates a discharging event.
1332 When this is 0 (active high), this is
1333 reversed. The default is 0 (active high)
1334 gpio_pull Desired pull-up/down state (off, down, up)
1336 type Set a charger type for the pin. (Default: mains)
1340 Info: Configure a GPIO pin to control a cooling fan.
1341 Load: dtoverlay=gpio-fan,<param>=<val>
1342 Params: gpiopin GPIO used to control the fan (default 12)
1343 temp Temperature at which the fan switches on, in
1344 millicelcius (default 55000)
1345 hyst Temperature delta (in millicelcius) below
1346 temp at which the fan will drop to minrpm
1351 Info: Activate a "hog" for a GPIO - request that the kernel configures it as
1352 an output, driven low or high as indicated by the presence or absence
1353 of the active_low parameter. Note that a hogged GPIO is not available
1354 to other drivers or for gpioset/gpioget.
1355 Load: dtoverlay=gpio-hog,<param>=<val>
1356 Params: gpio GPIO pin to hog (default 26)
1357 active_low If set, the hog drives the GPIO low (defaults
1358 to off - the GPIO is driven high)
1362 Info: Use GPIO pin as rc-core style infrared receiver input. The rc-core-
1363 based gpio_ir_recv driver maps received keys directly to a
1364 /dev/input/event* device, all decoding is done by the kernel - LIRC is
1365 not required! The key mapping and other decoding parameters can be
1366 configured by "ir-keytable" tool.
1367 Load: dtoverlay=gpio-ir,<param>=<val>
1368 Params: gpio_pin Input pin number. Default is 18.
1370 gpio_pull Desired pull-up/down state (off, down, up)
1373 invert "1" = invert the input (active-low signalling).
1374 "0" = non-inverted input (active-high
1375 signalling). Default is "1".
1377 rc-map-name Default rc keymap (can also be changed by
1378 ir-keytable), defaults to "rc-rc6-mce"
1382 Info: Use GPIO pin as bit-banged infrared transmitter output.
1383 This is an alternative to "pwm-ir-tx". gpio-ir-tx doesn't require
1384 a PWM so it can be used together with onboard analog audio.
1385 Load: dtoverlay=gpio-ir-tx,<param>=<val>
1386 Params: gpio_pin Output GPIO (default 18)
1388 invert "1" = invert the output (make it active-low).
1389 Default is "0" (active-high).
1393 Info: This is a generic overlay for activating GPIO keypresses using
1394 the gpio-keys library and this dtoverlay. Multiple keys can be
1395 set up using multiple calls to the overlay for configuring
1396 additional buttons or joysticks. You can see available keycodes
1397 at https://github.com/torvalds/linux/blob/v4.12/include/uapi/
1398 linux/input-event-codes.h#L64
1399 Load: dtoverlay=gpio-key,<param>=<val>
1400 Params: gpio GPIO pin to trigger on (default 3)
1401 active_low When this is 1 (active low), a falling
1402 edge generates a key down event and a
1403 rising edge generates a key up event.
1404 When this is 0 (active high), this is
1405 reversed. The default is 1 (active low)
1406 gpio_pull Desired pull-up/down state (off, down, up)
1407 Default is "up". Note that the default pin
1408 (GPIO3) has an external pullup
1409 label Set a label for the key
1410 keycode Set the key code for the button
1415 Info: This is a generic overlay for activating LEDs (or any other component)
1416 by a GPIO pin. Multiple LEDs can be set up using multiple calls to the
1417 overlay. While there are many existing methods to activate LEDs on the
1418 RPi, this method offers some advantages:
1419 1) Does not require any userspace programs.
1420 2) LEDs can be connected to the kernel's led-trigger framework,
1421 and drive the LED based on triggers such as cpu load, heartbeat,
1422 kernel panic, key input, timers and others.
1423 3) LED can be tied to the input state of another GPIO pin.
1424 4) The LED is setup early during the kernel boot process (useful
1425 for cpu/heartbeat/panic triggers).
1427 Typical electrical connection is:
1428 RPI-GPIO.19 -> LED -> 300ohm resister -> RPI-GND
1429 The GPIO pin number can be changed with the 'gpio=' parameter.
1431 To control an LED from userspace, write a 0 or 1 value:
1432 echo 1 > /sys/class/leds/myled1/brightness
1433 The 'myled1' name can be changed with the 'label=' parameter.
1435 To connect the LED to a kernel trigger from userspace:
1436 echo cpu > /sys/class/leds/myled1/trigger
1437 echo heartbeat > /sys/class/leds/myled1/trigger
1438 echo none > /sys/class/leds/myled1/trigger
1439 To connect the LED to GPIO.26 pin (physical pin 37):
1440 echo gpio > /sys/class/leds/myled1/trigger
1441 echo 26 > /sys/class/leds/myled1/gpio
1443 cat /sys/class/leds/myled1/trigger
1445 More information about the Linux kernel LED/Trigger system:
1446 https://www.kernel.org/doc/Documentation/leds/leds-class.rst
1447 https://www.kernel.org/doc/Documentation/leds/ledtrig-oneshot.rst
1448 Load: dtoverlay=gpio-led,<param>=<val>
1449 Params: gpio GPIO pin connected to the LED (default 19)
1450 label The label for this LED. It will appear under
1451 /sys/class/leds/<label> . Default 'myled1'.
1452 trigger Set the led-trigger to connect to this LED.
1453 default 'none' (LED is user-controlled).
1454 Some possible triggers:
1455 cpu - CPU load (all CPUs)
1456 cpu0 - CPU load of first CPU.
1457 mmc - disk activity (all disks)
1458 panic - turn on on kernel panic
1459 heartbeat - indicate system health
1460 gpio - connect to a GPIO input pin (note:
1461 currently the GPIO PIN can not be set
1462 using overlay parameters, must be
1463 done in userspace, see examples above.
1464 active_low Set to 1 to turn invert the LED control
1465 (writing 0 to /sys/class/leds/XXX/brightness
1466 will turn on the GPIO/LED). Default '0'.
1469 Name: gpio-no-bank0-irq
1470 Info: Use this overlay to disable GPIO interrupts for GPIOs in bank 0 (0-27),
1471 which can be useful for UIO drivers.
1472 N.B. Using this overlay will trigger a kernel WARN during booting, but
1473 this can safely be ignored - the system should work as expected.
1474 Load: dtoverlay=gpio-no-bank0-irq
1479 Info: Use this overlay to disable all GPIO interrupts, which can be useful
1480 for user-space GPIO edge detection systems.
1481 Load: dtoverlay=gpio-no-irq
1486 Info: Drives a GPIO high or low on poweroff (including halt). Using this
1487 overlay interferes with the normal power-down sequence, preventing the
1488 kernel from resetting the SoC (a necessary step in a normal power-off
1489 or reboot). This also disables the ability to trigger a boot by driving
1492 The GPIO starts in an inactive state. At poweroff time it is driven
1493 active for 100ms, then inactive for 100ms, then active again. It is
1494 safe to remove the power at any point after the initial activation of
1497 Users of this overlay are required to provide an external mechanism to
1498 switch off the power supply when signalled - failure to do so results
1499 in a kernel BUG, increased power consumption and undefined behaviour.
1500 Load: dtoverlay=gpio-poweroff,<param>=<val>
1501 Params: gpiopin GPIO for signalling (default 26)
1503 active_low Set if the power control device requires a
1504 high->low transition to trigger a power-down.
1505 Note that this will require the support of a
1506 custom dt-blob.bin to prevent a power-down
1507 during the boot process, and that a reboot
1508 will also cause the pin to go low.
1509 input Set if the gpio pin should be configured as
1511 export Set to export the configured pin to sysfs
1512 active_delay_ms Initial GPIO active period (default 100)
1513 inactive_delay_ms Subsequent GPIO inactive period (default 100)
1514 timeout_ms Specify (in ms) how long the kernel waits for
1515 power-down before issuing a WARN (default 3000).
1519 Info: Initiates a shutdown when GPIO pin changes. The given GPIO pin
1520 is configured as an input key that generates KEY_POWER events.
1522 This event is handled by systemd-logind by initiating a
1523 shutdown. Systemd versions older than 225 need an udev rule
1524 enable listening to the input device:
1526 ACTION!="REMOVE", SUBSYSTEM=="input", KERNEL=="event*", \
1527 SUBSYSTEMS=="platform", DRIVERS=="gpio-keys", \
1528 ATTRS{keys}=="116", TAG+="power-switch"
1530 Alternatively this event can be handled also on systems without
1531 systemd, just by traditional SysV init daemon. KEY_POWER event
1532 (keycode 116) needs to be mapped to KeyboardSignal on console
1533 and then kb::kbrequest inittab action which is triggered by
1534 KeyboardSignal from console can be configured to issue system
1535 shutdown. Steps for this configuration are:
1537 Add following lines to the /etc/console-setup/remap.inc file:
1539 # Key Power as special keypress
1540 keycode 116 = KeyboardSignal
1542 Then add following lines to /etc/inittab file:
1544 # Action on special keypress (Key Power)
1545 kb::kbrequest:/sbin/shutdown -t1 -a -h -P now
1547 And finally reload configuration by calling following commands:
1549 # dpkg-reconfigure console-setup
1550 # service console-setup reload
1553 This overlay only handles shutdown. After shutdown, the system
1554 can be powered up again by driving GPIO3 low. The default
1555 configuration uses GPIO3 with a pullup, so if you connect a
1556 button between GPIO3 and GND (pin 5 and 6 on the 40-pin header),
1557 you get a shutdown and power-up button. Please note that
1558 Raspberry Pi 1 Model B rev 1 uses GPIO1 instead of GPIO3.
1559 Load: dtoverlay=gpio-shutdown,<param>=<val>
1560 Params: gpio_pin GPIO pin to trigger on (default 3)
1561 For Raspberry Pi 1 Model B rev 1 set this
1562 explicitly to value 1, e.g.:
1564 dtoverlay=gpio-shutdown,gpio_pin=1
1566 active_low When this is 1 (active low), a falling
1567 edge generates a key down event and a
1568 rising edge generates a key up event.
1569 When this is 0 (active high), this is
1570 reversed. The default is 1 (active low).
1572 gpio_pull Desired pull-up/down state (off, down, up)
1575 Note that the default pin (GPIO3) has an
1576 external pullup. Same applies for GPIO1
1577 on Raspberry Pi 1 Model B rev 1.
1579 debounce Specify the debounce interval in milliseconds
1584 Info: Configures an HD44780 compatible LCD display. Uses 4 gpio pins for
1585 data, 2 gpio pins for enable and register select and 1 optional pin
1586 for enabling/disabling the backlight display.
1587 Load: dtoverlay=hd44780-lcd,<param>=<val>
1588 Params: pin_d4 GPIO pin for data pin D4 (default 6)
1590 pin_d5 GPIO pin for data pin D5 (default 13)
1592 pin_d6 GPIO pin for data pin D6 (default 19)
1594 pin_d7 GPIO pin for data pin D7 (default 26)
1596 pin_en GPIO pin for "Enable" (default 21)
1598 pin_rs GPIO pin for "Register Select" (default 20)
1600 pin_bl Optional pin for enabling/disabling the
1601 display backlight. (default disabled)
1603 display_height Height of the display in characters
1605 display_width Width of the display in characters
1608 Name: hdmi-backlight-hwhack-gpio
1609 Info: Devicetree overlay for GPIO based backlight on/off capability.
1610 Use this if you have one of those HDMI displays whose backlight cannot
1611 be controlled via DPMS over HDMI and plan to do a little soldering to
1612 use an RPi gpio pin for on/off switching. See:
1613 https://www.waveshare.com/wiki/7inch_HDMI_LCD_(C)#Backlight_Control
1614 Load: dtoverlay=hdmi-backlight-hwhack-gpio,<param>=<val>
1615 Params: gpio_pin GPIO pin used (default 17)
1616 active_low Set this to 1 if the display backlight is
1617 switched on when the wire goes low.
1618 Leave the default (value 0) if the backlight
1619 expects a high to switch it on.
1623 Info: Configures the HifiBerry Amp and Amp+ audio cards
1624 Load: dtoverlay=hifiberry-amp
1628 Name: hifiberry-amp100
1629 Info: Configures the HifiBerry AMP100 audio card
1630 Load: dtoverlay=hifiberry-amp100,<param>=<val>
1631 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1632 Digital volume control. Enable with
1633 "dtoverlay=hifiberry-amp100,24db_digital_gain"
1634 (The default behaviour is that the Digital
1635 volume control is limited to a maximum of
1636 0dB. ie. it can attenuate but not provide
1637 gain. For most users, this will be desired
1638 as it will prevent clipping. By appending
1639 the 24dB_digital_gain parameter, the Digital
1640 volume control will allow up to 24dB of
1641 gain. If this parameter is enabled, it is the
1642 responsibility of the user to ensure that
1643 the Digital volume control is set to a value
1644 that does not result in clipping/distortion!)
1645 slave Force DAC+ Pro into slave mode, using Pi as
1646 master for bit clock and frame clock.
1647 leds_off If set to 'true' the onboard indicator LEDs
1648 are switched off at all times.
1649 auto_mute If set to 'true' the amplifier is automatically
1650 muted when the DAC is not playing.
1651 mute_ext_ctl The amplifier's HW mute control is enabled
1652 in ALSA mixer and set to <val>.
1653 Will be overwritten by ALSA user settings.
1656 Name: hifiberry-amp3
1657 Info: Configures the HifiBerry Amp3 audio card
1658 Load: dtoverlay=hifiberry-amp3
1663 Info: Configures the HifiBerry DAC audio cards
1664 Load: dtoverlay=hifiberry-dac
1668 Name: hifiberry-dacplus
1669 Info: Configures the HifiBerry DAC+ audio card
1670 Load: dtoverlay=hifiberry-dacplus,<param>=<val>
1671 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1672 Digital volume control. Enable with
1673 "dtoverlay=hifiberry-dacplus,24db_digital_gain"
1674 (The default behaviour is that the Digital
1675 volume control is limited to a maximum of
1676 0dB. ie. it can attenuate but not provide
1677 gain. For most users, this will be desired
1678 as it will prevent clipping. By appending
1679 the 24dB_digital_gain parameter, the Digital
1680 volume control will allow up to 24dB of
1681 gain. If this parameter is enabled, it is the
1682 responsibility of the user to ensure that
1683 the Digital volume control is set to a value
1684 that does not result in clipping/distortion!)
1685 slave Force DAC+ Pro into slave mode, using Pi as
1686 master for bit clock and frame clock.
1687 leds_off If set to 'true' the onboard indicator LEDs
1688 are switched off at all times.
1691 Name: hifiberry-dacplusadc
1692 Info: Configures the HifiBerry DAC+ADC audio card
1693 Load: dtoverlay=hifiberry-dacplusadc,<param>=<val>
1694 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1695 Digital volume control. Enable with
1696 "dtoverlay=hifiberry-dacplus,24db_digital_gain"
1697 (The default behaviour is that the Digital
1698 volume control is limited to a maximum of
1699 0dB. ie. it can attenuate but not provide
1700 gain. For most users, this will be desired
1701 as it will prevent clipping. By appending
1702 the 24dB_digital_gain parameter, the Digital
1703 volume control will allow up to 24dB of
1704 gain. If this parameter is enabled, it is the
1705 responsibility of the user to ensure that
1706 the Digital volume control is set to a value
1707 that does not result in clipping/distortion!)
1708 slave Force DAC+ Pro into slave mode, using Pi as
1709 master for bit clock and frame clock.
1710 leds_off If set to 'true' the onboard indicator LEDs
1711 are switched off at all times.
1714 Name: hifiberry-dacplusadcpro
1715 Info: Configures the HifiBerry DAC+ADC PRO audio card
1716 Load: dtoverlay=hifiberry-dacplusadcpro,<param>=<val>
1717 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
1718 Digital volume control. Enable with
1719 "dtoverlay=hifiberry-dacplusadcpro,24db_digital_gain"
1720 (The default behaviour is that the Digital
1721 volume control is limited to a maximum of
1722 0dB. ie. it can attenuate but not provide
1723 gain. For most users, this will be desired
1724 as it will prevent clipping. By appending
1725 the 24dB_digital_gain parameter, the Digital
1726 volume control will allow up to 24dB of
1727 gain. If this parameter is enabled, it is the
1728 responsibility of the user to ensure that
1729 the Digital volume control is set to a value
1730 that does not result in clipping/distortion!)
1731 slave Force DAC+ADC Pro into slave mode, using Pi as
1732 master for bit clock and frame clock.
1733 leds_off If set to 'true' the onboard indicator LEDs
1734 are switched off at all times.
1737 Name: hifiberry-dacplusdsp
1738 Info: Configures the HifiBerry DAC+DSP audio card
1739 Load: dtoverlay=hifiberry-dacplusdsp
1743 Name: hifiberry-dacplushd
1744 Info: Configures the HifiBerry DAC+ HD audio card
1745 Load: dtoverlay=hifiberry-dacplushd
1749 Name: hifiberry-digi
1750 Info: Configures the HifiBerry Digi and Digi+ audio card
1751 Load: dtoverlay=hifiberry-digi
1755 Name: hifiberry-digi-pro
1756 Info: Configures the HifiBerry Digi+ Pro and Digi2 Pro audio card
1757 Load: dtoverlay=hifiberry-digi-pro
1762 Info: Enables "High Peripheral" mode
1763 Load: dtoverlay=highperi
1768 Info: HY28A - 2.8" TFT LCD Display Module by HAOYU Electronics
1769 Default values match Texy's display shield
1770 Load: dtoverlay=hy28a,<param>=<val>
1771 Params: speed Display SPI bus speed
1773 rotate Display rotation {0,90,180,270}
1775 fps Delay between frame updates
1777 debug Debug output level {0-7}
1779 xohms Touchpanel sensitivity (X-plate resistance)
1781 resetgpio GPIO used to reset controller
1783 ledgpio GPIO used to control backlight
1787 Info: HY28B - 2.8" TFT LCD Display Module by HAOYU Electronics
1788 Default values match Texy's display shield
1789 Load: dtoverlay=hy28b,<param>=<val>
1790 Params: speed Display SPI bus speed
1792 rotate Display rotation {0,90,180,270}
1794 fps Delay between frame updates
1796 debug Debug output level {0-7}
1798 xohms Touchpanel sensitivity (X-plate resistance)
1800 resetgpio GPIO used to reset controller
1802 ledgpio GPIO used to control backlight
1806 Info: HY28B 2017 version - 2.8" TFT LCD Display Module by HAOYU Electronics
1807 Default values match Texy's display shield
1808 Load: dtoverlay=hy28b-2017,<param>=<val>
1809 Params: speed Display SPI bus speed
1811 rotate Display rotation {0,90,180,270}
1813 fps Delay between frame updates
1815 debug Debug output level {0-7}
1817 xohms Touchpanel sensitivity (X-plate resistance)
1819 resetgpio GPIO used to reset controller
1821 ledgpio GPIO used to control backlight
1825 Info: Configures the Audiophonics I-SABRE Q2M DAC
1826 Load: dtoverlay=i-sabre-q2m
1831 Info: Fall back to the i2c_bcm2708 driver for the i2c_arm bus.
1832 Load: dtoverlay=i2c-bcm2708
1837 Info: Adds support for a number of I2C fan controllers
1838 Load: dtoverlay=i2c-fan,<param>=<val>
1839 Params: addr Sets the address for the fan controller. Note
1840 that the device must be configured to use the
1843 i2c0 Choose the I2C0 bus on GPIOs 0&1
1845 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
1847 i2c3 Choose the I2C3 bus (configure with the i2c3
1848 overlay - BCM2711 only)
1850 i2c4 Choose the I2C4 bus (configure with the i2c4
1851 overlay - BCM2711 only)
1853 i2c5 Choose the I2C5 bus (configure with the i2c5
1854 overlay - BCM2711 only)
1856 i2c6 Choose the I2C6 bus (configure with the i2c6
1857 overlay - BCM2711 only)
1859 minpwm PWM setting for the fan when the SoC is below
1860 mintemp (range 0-255. default 0)
1861 maxpwm PWM setting for the fan when the SoC is above
1862 maxtemp (range 0-255. default 255)
1863 midtemp Temperature (in millicelcius) at which the fan
1864 begins to speed up (default 50000)
1866 midtemp_hyst Temperature delta (in millicelcius) below
1867 mintemp at which the fan will drop to minrpm
1870 maxtemp Temperature (in millicelcius) at which the fan
1871 will be held at maxrpm (default 70000)
1873 maxtemp_hyst Temperature delta (in millicelcius) below
1874 maxtemp at which the fan begins to slow down
1877 emc2301 Select the Microchip EMC230x controller family
1878 - EMC2301, EMC2302, EMC2303, EMC2305.
1882 Info: Adds support for software i2c controller on gpio pins
1883 Load: dtoverlay=i2c-gpio,<param>=<val>
1884 Params: i2c_gpio_sda GPIO used for I2C data (default "23")
1886 i2c_gpio_scl GPIO used for I2C clock (default "24")
1888 i2c_gpio_delay_us Clock delay in microseconds
1889 (default "2" = ~100kHz)
1891 bus Set to a unique, non-zero value if wanting
1892 multiple i2c-gpio busses. If set, will be used
1893 as the preferred bus number (/dev/i2c-<n>). If
1894 not set, the default value is 0, but the bus
1895 number will be dynamically assigned - probably
1900 Info: Adds support for a number of I2C bus multiplexers on i2c_arm
1901 Load: dtoverlay=i2c-mux,<param>=<val>
1902 Params: pca9542 Select the NXP PCA9542 device
1904 pca9545 Select the NXP PCA9545 device
1906 pca9548 Select the NXP PCA9548 device
1908 addr Change I2C address of the device (default 0x70)
1910 i2c0 Choose the I2C0 bus on GPIOs 0&1
1912 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
1914 i2c3 Choose the I2C3 bus (configure with the i2c3
1915 overlay - BCM2711 only)
1917 i2c4 Choose the I2C3 bus (configure with the i2c3
1918 overlay - BCM2711 only)
1920 i2c5 Choose the I2C5 bus (configure with the i2c4
1921 overlay - BCM2711 only)
1923 i2c6 Choose the I2C6 bus (configure with the i2c6
1924 overlay - BCM2711 only)
1927 [ The i2c-mux-pca9548a overlay has been deleted. See i2c-mux. ]
1930 Name: i2c-pwm-pca9685a
1931 Info: Adds support for an NXP PCA9685A I2C PWM controller on i2c_arm
1932 Load: dtoverlay=i2c-pwm-pca9685a,<param>=<val>
1933 Params: addr I2C address of PCA9685A (default 0x40)
1934 i2c0 Choose the I2C0 bus on GPIOs 0&1
1935 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
1936 i2c3 Choose the I2C3 bus (configure with the i2c3
1937 overlay - BCM2711 only)
1938 i2c4 Choose the I2C3 bus (configure with the i2c3
1939 overlay - BCM2711 only)
1940 i2c5 Choose the I2C5 bus (configure with the i2c4
1941 overlay - BCM2711 only)
1942 i2c6 Choose the I2C6 bus (configure with the i2c6
1943 overlay - BCM2711 only)
1947 Info: Adds support for a number of I2C Real Time Clock devices
1948 Load: dtoverlay=i2c-rtc,<param>=<val>
1949 Params: abx80x Select one of the ABx80x family:
1950 AB0801, AB0803, AB0804, AB0805,
1951 AB1801, AB1803, AB1804, AB1805
1953 bq32000 Select the TI BQ32000 device
1955 ds1307 Select the DS1307 device
1957 ds1339 Select the DS1339 device
1959 ds1340 Select the DS1340 device
1961 ds3231 Select the DS3231 device
1963 m41t62 Select the M41T62 device
1965 mcp7940x Select the MCP7940x device
1967 mcp7941x Select the MCP7941x device
1969 pcf2127 Select the PCF2127 device
1971 pcf2129 Select the PCF2129 device
1973 pcf85063 Select the PCF85063 device
1975 pcf85063a Select the PCF85063A device
1977 pcf8523 Select the PCF8523 device
1979 pcf85363 Select the PCF85363 device
1981 pcf8563 Select the PCF8563 device
1983 rv1805 Select the Micro Crystal RV1805 device
1985 rv3028 Select the Micro Crystal RV3028 device
1987 rv3032 Select the Micro Crystal RV3032 device
1989 rv8803 Select the Micro Crystal RV8803 device
1991 sd3078 Select the ZXW Shenzhen whwave SD3078 device
1993 s35390a Select the ABLIC S35390A device
1995 i2c0 Choose the I2C0 bus on GPIOs 0&1
1997 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
1999 i2c3 Choose the I2C3 bus (configure with the i2c3
2000 overlay - BCM2711 only)
2002 i2c4 Choose the I2C3 bus (configure with the i2c3
2003 overlay - BCM2711 only)
2005 i2c5 Choose the I2C5 bus (configure with the i2c4
2006 overlay - BCM2711 only)
2008 i2c6 Choose the I2C6 bus (configure with the i2c6
2009 overlay - BCM2711 only)
2011 addr Sets the address for the RTC. Note that the
2012 device must be configured to use the specified
2015 trickle-diode-disable Do not use the internal trickle charger diode
2018 trickle-diode-type Diode type for trickle charge - "standard" or
2019 "schottky" (ABx80x and RV1805 only)
2021 trickle-resistor-ohms Resistor value for trickle charge (DS1339,
2022 ABx80x, BQ32000, RV1805, RV3028, RV3032)
2024 trickle-voltage-mv Charge pump voltage for trickle charge (RV3032)
2026 wakeup-source Specify that the RTC can be used as a wakeup
2029 backup-switchover-mode Backup power supply switch mode. Must be 0 for
2030 off or 1 for Vdd < VBackup (RV3028, RV3032)
2034 Info: Adds support for a number of I2C Real Time Clock devices
2035 using the software i2c controller
2036 Load: dtoverlay=i2c-rtc-gpio,<param>=<val>
2037 Params: abx80x Select one of the ABx80x family:
2038 AB0801, AB0803, AB0804, AB0805,
2039 AB1801, AB1803, AB1804, AB1805
2041 bq32000 Select the TI BQ32000 device
2043 ds1307 Select the DS1307 device
2045 ds1339 Select the DS1339 device
2047 ds1340 Select the DS1340 device
2049 ds3231 Select the DS3231 device
2051 m41t62 Select the M41T62 device
2053 mcp7940x Select the MCP7940x device
2055 mcp7941x Select the MCP7941x device
2057 pcf2127 Select the PCF2127 device
2059 pcf2129 Select the PCF2129 device
2061 pcf85063 Select the PCF85063 device
2063 pcf85063a Select the PCF85063A device
2065 pcf8523 Select the PCF8523 device
2067 pcf85363 Select the PCF85363 device
2069 pcf8563 Select the PCF8563 device
2071 rv1805 Select the Micro Crystal RV1805 device
2073 rv3028 Select the Micro Crystal RV3028 device
2075 rv3032 Select the Micro Crystal RV3032 device
2077 rv8803 Select the Micro Crystal RV8803 device
2079 sd3078 Select the ZXW Shenzhen whwave SD3078 device
2081 s35390a Select the ABLIC S35390A device
2083 addr Sets the address for the RTC. Note that the
2084 device must be configured to use the specified
2087 trickle-diode-disable Do not use the internal trickle charger diode
2090 trickle-diode-type Diode type for trickle charge - "standard" or
2091 "schottky" (ABx80x and RV1805 only)
2093 trickle-resistor-ohms Resistor value for trickle charge (DS1339,
2094 ABx80x, BQ32000, RV1805, RV3028, RV3032)
2096 trickle-voltage-mv Charge pump voltage for trickle charge (RV3032)
2098 wakeup-source Specify that the RTC can be used as a wakeup
2101 backup-switchover-mode Backup power supply switch mode. Must be 0 for
2102 off or 1 for Vdd < VBackup (RV3028, RV3032)
2104 i2c_gpio_sda GPIO used for I2C data (default "23")
2106 i2c_gpio_scl GPIO used for I2C clock (default "24")
2108 i2c_gpio_delay_us Clock delay in microseconds
2109 (default "2" = ~100kHz)
2113 Info: Adds support for a number of I2C barometric pressure, temperature,
2114 light level and chemical sensors on i2c_arm
2115 Load: dtoverlay=i2c-sensor,<param>=<val>
2116 Params: addr Set the address for the BH1750, BME280, BME680,
2117 BMP280, BMP380, CCS811, DS1621, HDC100X, JC42,
2118 LM75, MCP980x, MPU6050, MPU9250, MS5637, MS5803,
2119 MS5805, MS5837, MS8607, SHT3x or TMP102
2121 aht10 Select the Aosong AHT10 temperature and humidity
2124 bh1750 Select the Rohm BH1750 ambient light sensor
2125 Valid addresses 0x23 or 0x5c, default 0x23
2127 bme280 Select the Bosch Sensortronic BME280
2128 Valid addresses 0x76-0x77, default 0x76
2130 bme680 Select the Bosch Sensortronic BME680
2131 Valid addresses 0x76-0x77, default 0x76
2133 bmp085 Select the Bosch Sensortronic BMP085
2135 bmp180 Select the Bosch Sensortronic BMP180
2137 bmp280 Select the Bosch Sensortronic BMP280
2138 Valid addresses 0x76-0x77, default 0x76
2140 bmp380 Select the Bosch Sensortronic BMP380
2141 Valid addresses 0x76-0x77, default 0x76
2143 bno055 Select the Bosch Sensortronic BNO055 IMU
2144 Valid address 0x28-0x29, default 0x29
2146 ccs811 Select the AMS CCS811 digital gas sensor
2147 Valid addresses 0x5a-0x5b, default 0x5b
2149 ds1621 Select the Dallas Semiconductors DS1621 temp
2150 sensor. Valid addresses 0x48-0x4f, default 0x48
2152 hdc100x Select the Texas Instruments HDC100x temp sensor
2153 Valid addresses 0x40-0x43, default 0x40
2155 htu21 Select the HTU21 temperature and humidity sensor
2157 int_pin Set the GPIO to use for interrupts (max30102,
2158 mpu6050 and mpu9250 only)
2160 jc42 Select any of the many JEDEC JC42.4-compliant
2161 temperature sensors, including:
2162 ADT7408, AT30TS00, CAT34TS02, CAT6095,
2163 MAX6604, MCP9804, MCP9805, MCP9808,
2164 MCP98242, MCP98243, MCP98244, MCP9843,
2165 SE97, SE98, STTS424(E), STTS2002, STTS3000,
2166 TSE2002, TSE2004, TS3000, and TS3001.
2167 The default address is 0x18.
2169 lm75 Select the Maxim LM75 temperature sensor
2170 Valid addresses 0x48-0x4f, default 0x4f
2172 lm75addr Deprecated - use addr parameter instead
2174 max17040 Select the Maxim Integrated MAX17040 battery
2177 max30102 Select the Maxim Integrated MAX30102 heart-rate
2178 and blood-oxygen sensor
2180 mcp980x Select the Maxim MCP980x range of temperature
2181 sensors (i.e. MCP9800, MCP9801, MCP9802 and
2182 MCP9803). N.B. For MCP9804, MCP9805 and MCP9808,
2183 use the "jc42" option.
2184 Valid addresses are 0x18-0x1f (default 0x18)
2186 mpu6050 Select the InvenSense MPU6050 IMU. Valid
2187 valid addresses are 0x68 and 0x69 (default 0x68)
2189 mpu9250 Select the InvenSense MPU9250 IMU. Valid
2190 valid addresses are 0x68 and 0x69 (default 0x68)
2192 ms5637 Select the Measurement Specialities MS5637
2193 pressure and temperature sensor.
2195 ms5803 Select the Measurement Specialities MS5803
2196 pressure and temperature sensor.
2198 ms5805 Select the Measurement Specialities MS5805
2199 pressure and temperature sensor.
2201 ms5837 Select the Measurement Specialities MS5837
2202 pressure and temperature sensor.
2204 ms8607 Select the Measurement Specialities MS8607
2205 pressure and temperature sensor.
2207 no_timeout Disable the SMBUS timeout. N.B. Only supported
2208 by some jc42 devices - using with an
2209 incompatible device can stop it from being
2212 reset_pin GPIO to be used to reset the device (bno055
2213 only, disabled by default)
2215 sht3x Select the Sensirion SHT3x temperature and
2216 humidity sensors. Valid addresses 0x44-0x45,
2219 sht4x Select the Sensirion SHT4x temperature and
2220 humidity sensors. Valid addresses 0x44-0x45,
2223 si7020 Select the Silicon Labs Si7013/20/21 humidity/
2226 sps30 Select the Sensirion SPS30 particulate matter
2227 sensor. Fixed address 0x69.
2229 sgp30 Select the Sensirion SGP30 VOC sensor.
2232 tmp102 Select the Texas Instruments TMP102 temp sensor
2233 Valid addresses 0x48-0x4b, default 0x48
2235 tsl4531 Select the AMS TSL4531 digital ambient light
2238 veml6070 Select the Vishay VEML6070 ultraviolet light
2241 i2c0 Choose the I2C0 bus on GPIOs 0&1
2243 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
2245 i2c3 Choose the I2C3 bus (configure with the i2c3
2246 overlay - BCM2711 only)
2248 i2c4 Choose the I2C3 bus (configure with the i2c3
2249 overlay - BCM2711 only)
2251 i2c5 Choose the I2C5 bus (configure with the i2c4
2252 overlay - BCM2711 only)
2254 i2c6 Choose the I2C6 bus (configure with the i2c6
2255 overlay - BCM2711 only)
2259 Info: Change i2c0 pin usage. Not all pin combinations are usable on all
2260 platforms - platforms other then Compute Modules can only use this
2261 to disable transaction combining.
2262 Do NOT use in conjunction with dtparam=i2c_vc=on. From the 5.4 kernel
2263 onwards the base DT includes the use of i2c_mux_pinctrl to expose two
2264 muxings of BSC0 - GPIOs 0&1, and whichever combination is used for the
2265 camera and display connectors. This overlay disables that mux and
2266 configures /dev/i2c0 to point at whichever set of pins is requested.
2267 dtparam=i2c_vc=on will try and enable the mux, so combining the two
2268 will cause conflicts.
2269 Load: dtoverlay=i2c0,<param>=<val>
2270 Params: pins_0_1 Use pins 0 and 1 (default)
2271 pins_28_29 Use pins 28 and 29
2272 pins_44_45 Use pins 44 and 45
2273 pins_46_47 Use pins 46 and 47
2274 combine Allow transactions to be combined (default
2279 Info: Deprecated, legacy version of i2c0.
2284 Info: Enable i2c0 (Pi 5 only)
2285 Load: dtoverlay=i2c0-pi5,<param>=<val>
2286 Params: pins_0_1 Use GPIOs 0 and 1 (default)
2287 pins_8_9 Use GPIOs 8 and 9
2288 baudrate Set the baudrate for the interface (default
2293 Info: Change i2c1 pin usage. Not all pin combinations are usable on all
2294 platforms - platforms other then Compute Modules can only use this
2295 to disable transaction combining.
2296 Load: dtoverlay=i2c1,<param>=<val>
2297 Params: pins_2_3 Use pins 2 and 3 (default)
2298 pins_44_45 Use pins 44 and 45
2299 combine Allow transactions to be combined (default
2304 Info: Deprecated, legacy version of i2c1.
2309 Info: Enable i2c1 (Pi 5 only)
2310 Load: dtoverlay=i2c1-pi5,<param>=<val>
2311 Params: pins_2_3 Use GPIOs 2 and 3 (default)
2312 pins_10_11 Use GPIOs 10 and 11
2313 baudrate Set the baudrate for the interface (default
2318 Info: Enable i2c2 (Pi 5 only)
2319 Load: dtoverlay=i2c2-pi5,<param>=<val>
2320 Params: pins_4_5 Use GPIOs 4 and 5 (default)
2321 pins_12_13 Use GPIOs 12 and 13
2322 baudrate Set the baudrate for the interface (default
2327 Info: Enable the i2c3 bus. BCM2711 only.
2328 Load: dtoverlay=i2c3,<param>
2329 Params: pins_2_3 Use GPIOs 2 and 3
2330 pins_4_5 Use GPIOs 4 and 5 (default)
2331 baudrate Set the baudrate for the interface (default
2336 Info: Enable i2c3 (Pi 5 only)
2337 Load: dtoverlay=i2c3-pi5,<param>=<val>
2338 Params: pins_6_7 Use GPIOs 6 and 7 (default)
2339 pins_14_15 Use GPIOs 14 and 15
2340 pins_22_23 Use GPIOs 22 and 23
2341 baudrate Set the baudrate for the interface (default
2346 Info: Enable the i2c4 bus. BCM2711 only.
2347 Load: dtoverlay=i2c4,<param>
2348 Params: pins_6_7 Use GPIOs 6 and 7
2349 pins_8_9 Use GPIOs 8 and 9 (default)
2350 baudrate Set the baudrate for the interface (default
2355 Info: Enable the i2c5 bus. BCM2711 only.
2356 Load: dtoverlay=i2c5,<param>
2357 Params: pins_10_11 Use GPIOs 10 and 11
2358 pins_12_13 Use GPIOs 12 and 13 (default)
2359 baudrate Set the baudrate for the interface (default
2364 Info: Enable the i2c6 bus. BCM2711 only.
2365 Load: dtoverlay=i2c6,<param>
2366 Params: pins_0_1 Use GPIOs 0 and 1
2367 pins_22_23 Use GPIOs 22 and 23 (default)
2368 baudrate Set the baudrate for the interface (default
2373 Info: Configures any passive I2S DAC soundcard.
2374 Load: dtoverlay=i2s-dac
2379 Info: move I2S function block to GPIO 28 to 31
2380 Load: dtoverlay=i2s-gpio28-31
2385 Info: Enables I2C connected Ilitek 251x multiple touch controller using
2386 GPIO 4 (pin 7 on GPIO header) for interrupt.
2387 Load: dtoverlay=ilitek251x,<param>=<val>
2388 Params: interrupt GPIO used for interrupt (default 4)
2389 sizex Touchscreen size x, horizontal resolution of
2390 touchscreen (in pixels)
2391 sizey Touchscreen size y, vertical resolution of
2392 touchscreen (in pixels)
2396 Info: Sony IMX219 camera module.
2397 Uses Unicam 1, which is the standard camera connector on most Pi
2399 Load: dtoverlay=imx219,<param>=<val>
2400 Params: rotation Mounting rotation of the camera sensor (0 or
2402 orientation Sensor orientation (0 = front, 1 = rear,
2403 2 = external, default external)
2404 media-controller Configure use of Media Controller API for
2405 configuring the sensor (default on)
2406 cam0 Adopt the default configuration for CAM0 on a
2407 Compute Module (CSI0, i2c_vc, and cam0_reg).
2408 vcm Configure a VCM focus drive on the sensor.
2412 Info: Sony IMX258 camera module.
2413 Uses Unicam 1, which is the standard camera connector on most Pi
2415 Load: dtoverlay=imx258,<param>=<val>
2416 Params: rotation Mounting rotation of the camera sensor (0 or
2418 orientation Sensor orientation (0 = front, 1 = rear,
2419 2 = external, default external)
2420 media-controller Configure use of Media Controller API for
2421 configuring the sensor (default on)
2422 cam0 Adopt the default configuration for CAM0 on a
2423 Compute Module (CSI0, i2c_vc, and cam0_reg).
2424 vcm Configure a VCM focus drive on the sensor.
2425 4lane Enable 4 CSI2 lanes. This requires a Compute
2426 Module (1, 3, or 4).
2430 Info: Sony IMX290 camera module.
2431 Uses Unicam 1, which is the standard camera connector on most Pi
2433 Load: dtoverlay=imx290,<param>
2434 Params: 4lane Enable 4 CSI2 lanes. This requires a Compute
2435 Module (1, 3, or 4).
2436 clock-frequency Sets the clock frequency to match that used on
2438 Modules from Vision Components use 37.125MHz
2439 (the default), whilst those from Innomaker use
2441 mono Denote that the module is a mono sensor.
2442 orientation Sensor orientation (0 = front, 1 = rear,
2443 2 = external, default external)
2444 rotation Mounting rotation of the camera sensor (0 or
2446 media-controller Configure use of Media Controller API for
2447 configuring the sensor (default on)
2448 cam0 Adopt the default configuration for CAM0 on a
2449 Compute Module (CSI0, i2c_vc, and cam0_reg).
2453 Info: Sony IMX296 camera module.
2454 Uses Unicam 1, which is the standard camera connector on most Pi
2456 Load: dtoverlay=imx296,<param>=<val>
2457 Params: rotation Mounting rotation of the camera sensor (0 or
2459 orientation Sensor orientation (0 = front, 1 = rear,
2460 2 = external, default external)
2461 media-controller Configure use of Media Controller API for
2462 configuring the sensor (default on)
2463 cam0 Adopt the default configuration for CAM0 on a
2464 Compute Module (CSI0, i2c_vc, and cam0_reg).
2465 clock-frequency Sets the clock frequency to match that used on
2466 the board, which should be one of 54000000
2467 (the default), 37125000 or 74250000.
2471 Info: Sony IMX327 camera module.
2472 Uses Unicam 1, which is the standard camera connector on most Pi
2474 Load: dtoverlay=imx327,<param>
2475 Params: 4lane Enable 4 CSI2 lanes. This requires a Compute
2476 Module (1, 3, or 4).
2477 clock-frequency Sets the clock frequency to match that used on
2479 Modules from Vision Components use 37.125MHz
2480 (the default), whilst those from Innomaker use
2482 mono Denote that the module is a mono sensor.
2483 orientation Sensor orientation (0 = front, 1 = rear,
2484 2 = external, default external)
2485 rotation Mounting rotation of the camera sensor (0 or
2487 media-controller Configure use of Media Controller API for
2488 configuring the sensor (default on)
2489 cam0 Adopt the default configuration for CAM0 on a
2490 Compute Module (CSI0, i2c_vc, and cam0_reg).
2494 Info: Sony IMX378 camera module.
2495 Uses Unicam 1, which is the standard camera connector on most Pi
2497 Load: dtoverlay=imx378,<param>=<val>
2498 Params: rotation Mounting rotation of the camera sensor (0 or
2500 orientation Sensor orientation (0 = front, 1 = rear,
2501 2 = external, default external)
2502 media-controller Configure use of Media Controller API for
2503 configuring the sensor (default on)
2504 cam0 Adopt the default configuration for CAM0 on a
2505 Compute Module (CSI0, i2c_vc, and cam0_reg).
2509 Info: Sony IMX462 camera module.
2510 Uses Unicam 1, which is the standard camera connector on most Pi
2512 Load: dtoverlay=imx462,<param>
2513 Params: 4lane Enable 4 CSI2 lanes. This requires a Compute
2514 Module (1, 3, or 4).
2515 clock-frequency Sets the clock frequency to match that used on
2517 Modules from Vision Components use 37.125MHz
2518 (the default), whilst those from Innomaker use
2520 mono Denote that the module is a mono sensor.
2521 orientation Sensor orientation (0 = front, 1 = rear,
2522 2 = external, default external)
2523 rotation Mounting rotation of the camera sensor (0 or
2525 media-controller Configure use of Media Controller API for
2526 configuring the sensor (default on)
2527 cam0 Adopt the default configuration for CAM0 on a
2528 Compute Module (CSI0, i2c_vc, and cam0_reg).
2532 Info: Sony IMX477 camera module.
2533 Uses Unicam 1, which is the standard camera connector on most Pi
2535 Load: dtoverlay=imx477,<param>=<val>
2536 Params: rotation Mounting rotation of the camera sensor (0 or
2538 orientation Sensor orientation (0 = front, 1 = rear,
2539 2 = external, default external)
2540 media-controller Configure use of Media Controller API for
2541 configuring the sensor (default on)
2542 cam0 Adopt the default configuration for CAM0 on a
2543 Compute Module (CSI0, i2c_vc, and cam0_reg).
2547 Info: Sony IMX519 camera module.
2548 Uses Unicam 1, which is the standard camera connector on most Pi
2550 Load: dtoverlay=imx519,<param>=<val>
2551 Params: rotation Mounting rotation of the camera sensor (0 or
2553 orientation Sensor orientation (0 = front, 1 = rear,
2554 2 = external, default external)
2555 media-controller Configure use of Media Controller API for
2556 configuring the sensor (default on)
2557 cam0 Adopt the default configuration for CAM0 on a
2558 Compute Module (CSI0, i2c_vc, and cam0_reg).
2559 vcm Select lens driver state. Default is enabled,
2560 but vcm=off will disable.
2564 Info: Sony IMX708 camera module.
2565 Uses Unicam 1, which is the standard camera connector on most Pi
2567 Load: dtoverlay=imx708,<param>=<val>
2568 Params: rotation Mounting rotation of the camera sensor (0 or
2570 orientation Sensor orientation (0 = front, 1 = rear,
2571 2 = external, default external)
2572 vcm Select lens driver state. Default is enabled,
2573 but vcm=off will disable.
2574 media-controller Configure use of Media Controller API for
2575 configuring the sensor (default on)
2576 cam0 Adopt the default configuration for CAM0 on a
2577 Compute Module (CSI0, i2c_vc, and cam0_reg).
2578 link-frequency Allowable link frequency values to use in Hz:
2579 450000000 (default), 447000000, 453000000.
2583 Info: Configures the IQaudio Codec audio card
2584 Load: dtoverlay=iqaudio-codec
2589 Info: Configures the IQaudio DAC audio card
2590 Load: dtoverlay=iqaudio-dac,<param>
2591 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2592 Digital volume control. Enable with
2593 "dtoverlay=iqaudio-dac,24db_digital_gain"
2594 (The default behaviour is that the Digital
2595 volume control is limited to a maximum of
2596 0dB. ie. it can attenuate but not provide
2597 gain. For most users, this will be desired
2598 as it will prevent clipping. By appending
2599 the 24db_digital_gain parameter, the Digital
2600 volume control will allow up to 24dB of
2601 gain. If this parameter is enabled, it is the
2602 responsibility of the user to ensure that
2603 the Digital volume control is set to a value
2604 that does not result in clipping/distortion!)
2607 Name: iqaudio-dacplus
2608 Info: Configures the IQaudio DAC+ audio card
2609 Load: dtoverlay=iqaudio-dacplus,<param>=<val>
2610 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2611 Digital volume control. Enable with
2612 "dtoverlay=iqaudio-dacplus,24db_digital_gain"
2613 (The default behaviour is that the Digital
2614 volume control is limited to a maximum of
2615 0dB. ie. it can attenuate but not provide
2616 gain. For most users, this will be desired
2617 as it will prevent clipping. By appending
2618 the 24db_digital_gain parameter, the Digital
2619 volume control will allow up to 24dB of
2620 gain. If this parameter is enabled, it is the
2621 responsibility of the user to ensure that
2622 the Digital volume control is set to a value
2623 that does not result in clipping/distortion!)
2624 auto_mute_amp If specified, unmute/mute the IQaudIO amp when
2625 starting/stopping audio playback.
2626 unmute_amp If specified, unmute the IQaudIO amp once when
2627 the DAC driver module loads.
2630 Name: iqaudio-digi-wm8804-audio
2631 Info: Configures the IQAudIO Digi WM8804 audio card
2632 Load: dtoverlay=iqaudio-digi-wm8804-audio,<param>=<val>
2633 Params: card_name Override the default, "IQAudIODigi", card name.
2634 dai_name Override the default, "IQAudIO Digi", dai name.
2635 dai_stream_name Override the default, "IQAudIO Digi HiFi",
2640 Info: Enables I2C connected Azoteq IQS550 trackpad/touchscreen controller
2641 using GPIO 4 (pin 7 on GPIO header) for interrupt.
2642 Load: dtoverlay=iqs550,<param>=<val>
2643 Params: interrupt GPIO used for interrupt (default 4)
2644 reset GPIO used for reset (optional)
2645 sizex Touchscreen size x (default 800)
2646 sizey Touchscreen size y (default 480)
2647 invx Touchscreen inverted x axis
2648 invy Touchscreen inverted y axis
2649 swapxy Touchscreen swapped x y axis
2653 Info: Infineon irs1125 TOF camera module.
2654 Uses Unicam 1, which is the standard camera connector on most Pi
2656 Load: dtoverlay=irs1125,<param>=<val>
2657 Params: media-controller Configure use of Media Controller API for
2658 configuring the sensor (default off)
2659 cam0 Adopt the default configuration for CAM0 on a
2660 Compute Module (CSI0, i2c_vc, and cam0_reg).
2664 Info: Adds support for JEDEC-compliant SPI NOR flash devices. (Note: The
2665 "jedec,spi-nor" kernel driver was formerly known as "m25p80".)
2666 Load: dtoverlay=jedec-spi-nor,<param>=<val>
2667 Params: spi<n>-<m> Enable flash device on SPI<n>, CS#<m>
2668 fastr Add fast read capability to the flash device
2669 speed Maximum SPI frequency (Hz)
2670 flash-spi<n>-<m> Same as spi<n>-<m> (deprecated)
2671 flash-fastr-spi<n>-<m> Same as spi<n>->m>,fastr (deprecated)
2675 Info: Simultaneous usage of an justboom-dac and justboom-digi based
2677 Load: dtoverlay=justboom-both,<param>=<val>
2678 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2679 Digital volume control. Enable with
2680 "dtoverlay=justboom-dac,24db_digital_gain"
2681 (The default behaviour is that the Digital
2682 volume control is limited to a maximum of
2683 0dB. ie. it can attenuate but not provide
2684 gain. For most users, this will be desired
2685 as it will prevent clipping. By appending
2686 the 24dB_digital_gain parameter, the Digital
2687 volume control will allow up to 24dB of
2688 gain. If this parameter is enabled, it is the
2689 responsibility of the user to ensure that
2690 the Digital volume control is set to a value
2691 that does not result in clipping/distortion!)
2695 Info: Configures the JustBoom DAC HAT, Amp HAT, DAC Zero and Amp Zero audio
2697 Load: dtoverlay=justboom-dac,<param>=<val>
2698 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
2699 Digital volume control. Enable with
2700 "dtoverlay=justboom-dac,24db_digital_gain"
2701 (The default behaviour is that the Digital
2702 volume control is limited to a maximum of
2703 0dB. ie. it can attenuate but not provide
2704 gain. For most users, this will be desired
2705 as it will prevent clipping. By appending
2706 the 24dB_digital_gain parameter, the Digital
2707 volume control will allow up to 24dB of
2708 gain. If this parameter is enabled, it is the
2709 responsibility of the user to ensure that
2710 the Digital volume control is set to a value
2711 that does not result in clipping/distortion!)
2715 Info: Configures the JustBoom Digi HAT and Digi Zero audio cards
2716 Load: dtoverlay=justboom-digi
2721 Info: This overlay has been deprecated and removed - see gpio-ir
2726 Info: Adds support for the ltc294x family of battery gauges
2727 Load: dtoverlay=ltc294x,<param>=<val>
2728 Params: ltc2941 Select the ltc2941 device
2730 ltc2942 Select the ltc2942 device
2732 ltc2943 Select the ltc2943 device
2734 ltc2944 Select the ltc2944 device
2736 resistor-sense The sense resistor value in milli-ohms.
2737 Can be a 32-bit negative value when the battery
2738 has been connected to the wrong end of the
2741 prescaler-exponent Range and accuracy of the gauge. The value is
2742 programmed into the chip only if it differs
2743 from the current setting.
2745 - Default value is 128
2746 - the exponent is in the range 0-7 (default 7)
2747 See the datasheet for more information.
2751 Info: Configures the Maxim MAX98357A I2S DAC
2752 Load: dtoverlay=max98357a,<param>=<val>
2753 Params: no-sdmode Driver does not manage the state of the DAC's
2754 SD_MODE pin (i.e. chip is always on).
2755 sdmode-pin integer, GPIO pin connected to the SD_MODE input
2756 of the DAC (default GPIO4 if parameter omitted).
2760 Info: Configure a MAX6675, MAX31855 or MAX31856 thermocouple as an IIO device.
2762 For devices on spi1 or spi2, the interfaces should be enabled
2763 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2764 The overlay expects to disable the relevant spidev node, so also using
2765 e.g. cs0_spidev=off is unnecessary.
2768 MAX31855 on /dev/spidev0.0
2769 dtoverlay=maxtherm,spi0-0,max31855
2770 MAX31856 using a type J thermocouple on /dev/spidev2.1
2772 dtoverlay=maxtherm,spi2-1,max31856,type_j
2774 Load: dtoverlay=maxtherm,<param>=<val>
2775 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2777 max6675 Enable support for the MAX6675 (default)
2778 max31855 Enable support for the MAX31855
2779 max31855e Enable support for the MAX31855E
2780 max31855j Enable support for the MAX31855J
2781 max31855k Enable support for the MAX31855K
2782 max31855n Enable support for the MAX31855N
2783 max31855r Enable support for the MAX31855R
2784 max31855s Enable support for the MAX31855S
2785 max31855t Enable support for the MAX31855T
2786 max31856 Enable support for the MAX31856 (with type K)
2787 type_b Select a type B sensor for max31856
2788 type_e Select a type E sensor for max31856
2789 type_j Select a type J sensor for max31856
2790 type_k Select a type K sensor for max31856
2791 type_n Select a type N sensor for max31856
2792 type_r Select a type R sensor for max31856
2793 type_s Select a type S sensor for max31856
2794 type_t Select a type T sensor for max31856
2798 Info: Configures the mbed AudioCODEC (TLV320AIC23B)
2799 Load: dtoverlay=mbed-dac
2804 Info: Configures the MCP23017 I2C GPIO expander
2805 Load: dtoverlay=mcp23017,<param>=<val>
2806 Params: gpiopin Gpio pin connected to the INTA output of the
2807 MCP23017 (default: 4)
2809 addr I2C address of the MCP23017 (default: 0x20)
2811 mcp23008 Configure an MCP23008 instead.
2812 noints Disable the interrupt GPIO line.
2816 Info: Configures the MCP23S08/17 SPI GPIO expanders.
2817 If devices are present on SPI1 or SPI2, those interfaces must be enabled
2818 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2819 If interrupts are enabled for a device on a given CS# on a SPI bus, that
2820 device must be the only one present on that SPI bus/CS#.
2821 Load: dtoverlay=mcp23s17,<param>=<val>
2822 Params: s08-spi<n>-<m>-present 4-bit integer, bitmap indicating MCP23S08
2823 devices present on SPI<n>, CS#<m>
2825 s17-spi<n>-<m>-present 8-bit integer, bitmap indicating MCP23S17
2826 devices present on SPI<n>, CS#<m>
2828 s08-spi<n>-<m>-int-gpio integer, enables interrupts on a single
2829 MCP23S08 device on SPI<n>, CS#<m>, specifies
2830 the GPIO pin to which INT output of MCP23S08
2833 s17-spi<n>-<m>-int-gpio integer, enables mirrored interrupts on a
2834 single MCP23S17 device on SPI<n>, CS#<m>,
2835 specifies the GPIO pin to which either INTA
2836 or INTB output of MCP23S17 is connected.
2840 Info: Configures the MCP2515 CAN controller on spi0/1/2
2841 For devices on spi1 or spi2, the interfaces should be enabled
2842 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2843 Load: dtoverlay=mcp2515,<param>=<val>
2844 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2847 oscillator Clock frequency for the CAN controller (Hz)
2849 speed Maximum SPI frequence (Hz)
2851 interrupt GPIO for interrupt signal
2855 Info: Configures the MCP2515 CAN controller on spi0.0
2856 Load: dtoverlay=mcp2515-can0,<param>=<val>
2857 Params: oscillator Clock frequency for the CAN controller (Hz)
2859 spimaxfrequency Maximum SPI frequence (Hz)
2861 interrupt GPIO for interrupt signal
2865 Info: Configures the MCP2515 CAN controller on spi0.1
2866 Load: dtoverlay=mcp2515-can1,<param>=<val>
2867 Params: oscillator Clock frequency for the CAN controller (Hz)
2869 spimaxfrequency Maximum SPI frequence (Hz)
2871 interrupt GPIO for interrupt signal
2875 Info: Configures the MCP251XFD CAN controller family
2876 For devices on spi1 or spi2, the interfaces should be enabled
2877 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2878 Load: dtoverlay=mcp251xfd,<param>=<val>
2879 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2882 oscillator Clock frequency for the CAN controller (Hz)
2884 speed Maximum SPI frequence (Hz)
2886 interrupt GPIO for interrupt signal
2888 rx_interrupt GPIO for RX interrupt signal (nINT1) (optional)
2890 xceiver_enable GPIO for CAN transceiver enable (optional)
2892 xceiver_active_high specifiy if CAN transceiver enable pin is
2893 active high (optional, default: active low)
2897 Info: Configures MCP3008 A/D converters
2898 For devices on spi1 or spi2, the interfaces should be enabled
2899 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2900 Load: dtoverlay=mcp3008,<param>[=<val>]
2901 Params: spi<n>-<m>-present boolean, configure device at spi<n>, cs<m>
2902 spi<n>-<m>-speed integer, set the spi bus speed for this device
2906 Info: Configures MCP3202 A/D converters
2907 For devices on spi1 or spi2, the interfaces should be enabled
2908 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2909 Load: dtoverlay=mcp3202,<param>[=<val>]
2910 Params: spi<n>-<m>-present boolean, configure device at spi<n>, cs<m>
2911 spi<n>-<m>-speed integer, set the spi bus speed for this device
2915 Info: Overlay for activation of Microchip MCP3421-3428 ADCs over I2C
2916 Load: dtoverlay=mcp342x,<param>=<val>
2917 Params: addr I2C bus address of device, for devices with
2918 addresses that are configurable, e.g. by
2919 hardware links (default=0x68)
2920 mcp3421 The device is an MCP3421
2921 mcp3422 The device is an MCP3422
2922 mcp3423 The device is an MCP3423
2923 mcp3424 The device is an MCP3424
2924 mcp3425 The device is an MCP3425
2925 mcp3426 The device is an MCP3426
2926 mcp3427 The device is an MCP3427
2927 mcp3428 The device is an MCP3428
2931 Info: Media Center HAT - 2.83" Touch Display + extras by Pi Supply
2932 Load: dtoverlay=media-center,<param>=<val>
2933 Params: speed Display SPI bus speed
2934 rotate Display rotation {0,90,180,270}
2935 fps Delay between frame updates
2936 xohms Touchpanel sensitivity (X-plate resistance)
2937 swapxy Swap x and y axis
2938 backlight Change backlight GPIO pin {e.g. 12, 18}
2939 debug "on" = enable additional debug messages
2944 Info: Configures the merus-amp audio card
2945 Load: dtoverlay=merus-amp
2950 Info: Configures UART0 (ttyAMA0) so that a requested 38.4kbaud actually gets
2951 31.25kbaud, the frequency required for MIDI
2952 Load: dtoverlay=midi-uart0
2956 Name: midi-uart0-pi5
2957 Info: See midi-uart0 (this is the Pi 5 version)
2961 Info: Configures UART1 (ttyS0) so that a requested 38.4kbaud actually gets
2962 31.25kbaud, the frequency required for MIDI
2963 Load: dtoverlay=midi-uart1
2967 Name: midi-uart1-pi5
2968 Info: See midi-uart1 (this is the Pi 5 version)
2972 Info: Configures UART2 (ttyAMA2) so that a requested 38.4kbaud actually gets
2973 31.25kbaud, the frequency required for MIDI
2974 Load: dtoverlay=midi-uart2
2978 Name: midi-uart2-pi5
2979 Info: See midi-uart2 (this is the Pi 5 version)
2983 Info: Configures UART3 (ttyAMA3) so that a requested 38.4kbaud actually gets
2984 31.25kbaud, the frequency required for MIDI
2985 Load: dtoverlay=midi-uart3
2989 Name: midi-uart3-pi5
2990 Info: See midi-uart3 (this is the Pi 5 version)
2994 Info: Configures UART4 (ttyAMA4) so that a requested 38.4kbaud actually gets
2995 31.25kbaud, the frequency required for MIDI
2996 Load: dtoverlay=midi-uart4
3000 Name: midi-uart4-pi5
3001 Info: See midi-uart4 (this is the Pi 5 version)
3005 Info: Configures UART5 (ttyAMA5) so that a requested 38.4kbaud actually gets
3006 31.25kbaud, the frequency required for MIDI
3007 Load: dtoverlay=midi-uart5
3012 Info: Overlay for AdaFruit Mini Pi 1.3" TFT via SPI using fbtft driver.
3013 Load: dtoverlay=minipitft13,<param>=<val>
3014 Params: speed SPI bus speed (default 32000000)
3015 rotate Display rotation (0, 90, 180 or 270; default 0)
3016 width Display width (default 240)
3017 height Display height (default 240)
3018 fps Delay between frame updates (default 25)
3019 debug Debug output level (0-7; default 0)
3023 Info: Switch the onboard Bluetooth function of a BT-equipped Raspberry Pi
3024 to use the mini-UART (ttyS0) and restore UART0/ttyAMA0 over GPIOs 14 &
3025 15. Note that this option uses a lower baudrate, and should only be used
3026 with low-bandwidth peripherals.
3027 Load: dtoverlay=miniuart-bt,<param>=<val>
3028 Params: krnbt Set to "off" to disable autoprobing of Bluetooth
3029 driver without need of hciattach/btattach
3033 Info: Overlay for SPI-connected MIPI DBI displays using the panel-mipi-dbi
3034 driver. The driver will load a file /lib/firmware/panel.bin containing
3035 the initialisation commands.
3038 dtoverlay=mipi-dbi-spi,spi0-0,speed=70000000
3039 dtparam=width=320,height=240
3040 dtparam=reset-gpio=23,dc-gpio=24
3041 dtparam=backlight-gpio=18
3043 Compared to fbtft panel-mipi-dbi runs pixel data at spi-max-frequency
3044 and init commands at 10MHz. This makes it possible to push the envelope
3045 without messing up the controller configuration due to command
3046 transmission errors.
3048 For devices on spi1 or spi2, the interfaces should be enabled
3049 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
3051 See https://github.com/notro/panel-mipi-dbi/wiki for more info.
3053 Load: dtoverlay=mipi-dbi-spi,<param>=<val>
3055 compatible Set the compatible string to load a different
3056 firmware file. Both the panel compatible value
3057 used to load the firmware file and the value
3058 used to load the driver has to be set having a
3059 NUL (\0) separator between them.
3061 dtparam=compatible=mypanel\0panel-mipi-dbi-spi
3062 spi<n>-<m> Configure device at spi<n>, cs<m>
3064 speed SPI bus speed in Hz (default 32000000)
3065 cpha Shifted SPI clock phase (CPHA) mode
3066 cpol Inverse SPI clock polarity (CPOL) mode
3067 write-only Controller is not readable
3068 (ie. MISO is not wired up).
3070 width Panel width in pixels (required)
3071 height Panel height in pixels (required)
3072 width-mm Panel width in mm
3073 height-mm Panel height in mm
3074 x-offset Panel x-offset in controller RAM
3075 y-offset Panel y-offset in controller RAM
3077 clock-frequency Panel clock frequency in Hz
3078 (optional, just informational).
3080 reset-gpio GPIO pin to be used for RESET
3081 dc-gpio GPIO pin to be used for D/C
3083 backlight-gpio GPIO pin to be used for backlight control
3085 backlight-pwm PWM channel to be used for backlight control
3086 (default of none). NB Disables audio headphone
3087 output as that also uses PWM.
3088 backlight-pwm-chan Choose channel on &pwm node for backlight
3089 control (default 0).
3090 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
3091 pwm-2chan for valid options (default 18).
3092 backlight-pwm-func Pin function of GPIO used for the PWM backlight.
3093 See pwm-2chan for valid options (default 2).
3094 backlight-def-brightness
3095 Set the default brightness. Normal range 1-16.
3100 Info: Overlay for i2c connected mlx90640 thermal camera
3101 Load: dtoverlay=mlx90640
3106 Info: Selects the bcm2835-mmc SD/MMC driver, optionally with overclock
3107 Load: dtoverlay=mmc,<param>=<val>
3108 Params: overclock_50 Clock (in MHz) to use when the MMC framework
3113 Info: This overlay has been deprecated - use "dtoverlay=i2c-sensor,mpu6050"
3114 instead. Note that "int_pin" is the new name for the "interrupt"
3120 Info: MZ61581 display by Tontec
3121 Load: dtoverlay=mz61581,<param>=<val>
3122 Params: speed Display SPI bus speed
3124 rotate Display rotation {0,90,180,270}
3126 fps Delay between frame updates
3128 txbuflen Transmit buffer length (default 32768)
3130 debug Debug output level {0-7}
3132 xohms Touchpanel sensitivity (X-plate resistance)
3136 Info: Omnivision OV2311 camera module.
3137 Uses Unicam 1, which is the standard camera connector on most Pi
3139 Load: dtoverlay=ov2311,<param>=<val>
3140 Params: rotation Mounting rotation of the camera sensor (0 or
3142 orientation Sensor orientation (0 = front, 1 = rear,
3143 2 = external, default external)
3144 media-controller Configure use of Media Controller API for
3145 configuring the sensor (default on)
3146 cam0 Adopt the default configuration for CAM0 on a
3147 Compute Module (CSI0, i2c_vc, and cam0_reg).
3151 Info: Omnivision OV5647 camera module.
3152 Uses Unicam 1, which is the standard camera connector on most Pi
3154 Load: dtoverlay=ov5647,<param>=<val>
3155 Params: rotation Mounting rotation of the camera sensor (0 or
3157 orientation Sensor orientation (0 = front, 1 = rear,
3158 2 = external, default external)
3159 media-controller Configure use of Media Controller API for
3160 configuring the sensor (default on)
3161 cam0 Adopt the default configuration for CAM0 on a
3162 Compute Module (CSI0, i2c_vc, and cam0_reg).
3163 vcm Configure a VCM focus drive on the sensor.
3167 Info: Omnivision OV7251 camera module.
3168 Uses Unicam 1, which is the standard camera connector on most Pi
3170 Load: dtoverlay=ov7251,<param>=<val>
3171 Params: rotation Mounting rotation of the camera sensor (0 or
3173 orientation Sensor orientation (0 = front, 1 = rear,
3174 2 = external, default external)
3175 media-controller Configure use of Media Controller API for
3176 configuring the sensor (default off)
3177 cam0 Adopt the default configuration for CAM0 on a
3178 Compute Module (CSI0, i2c_vc, and cam0_reg).
3182 Info: Omnivision OV9281 camera module.
3183 Uses Unicam 1, which is the standard camera connector on most Pi
3185 Load: dtoverlay=ov9281,<param>=<val>
3186 Params: rotation Mounting rotation of the camera sensor (0 or
3188 orientation Sensor orientation (0 = front, 1 = rear,
3189 2 = external, default external)
3190 media-controller Configure use of Media Controller API for
3191 configuring the sensor (default on)
3192 cam0 Adopt the default configuration for CAM0 on a
3193 Compute Module (CSI0, i2c_vc, and cam0_reg).
3197 Info: PaPiRus ePaper Screen by Pi Supply (both HAT and pHAT)
3198 Load: dtoverlay=papirus,<param>=<val>
3199 Params: panel Display panel (required):
3204 speed Display SPI bus speed
3208 Info: TI PCA953x family of I2C GPIO expanders. Default is for NXP PCA9534.
3209 Load: dtoverlay=pca953x,<param>=<val>
3210 Params: addr I2C address of expander. Default 0x20.
3211 pca6416 Select the NXP PCA6416 (16 bit)
3212 pca9505 Select the NXP PCA9505 (40 bit)
3213 pca9535 Select the NXP PCA9535 (16 bit)
3214 pca9536 Select the NXP PCA9536 or TI PCA9536 (4 bit)
3215 pca9537 Select the NXP PCA9537 (4 bit)
3216 pca9538 Select the NXP PCA9538 (8 bit)
3217 pca9539 Select the NXP PCA9539 (16 bit)
3218 pca9554 Select the NXP PCA9554 (8 bit)
3219 pca9555 Select the NXP PCA9555 (16 bit)
3220 pca9556 Select the NXP PCA9556 (8 bit)
3221 pca9557 Select the NXP PCA9557 (8 bit)
3222 pca9574 Select the NXP PCA9574 (8 bit)
3223 pca9575 Select the NXP PCA9575 (16 bit)
3224 pca9698 Select the NXP PCA9698 (40 bit)
3225 pcal6416 Select the NXP PCAL6416 (16 bit)
3226 pcal6524 Select the NXP PCAL6524 (24 bit)
3227 pcal9555a Select the NXP PCAL9555A (16 bit)
3228 max7310 Select the Maxim MAX7310 (8 bit)
3229 max7312 Select the Maxim MAX7312 (16 bit)
3230 max7313 Select the Maxim MAX7313 (16 bit)
3231 max7315 Select the Maxim MAX7315 (8 bit)
3232 pca6107 Select the TI PCA6107 (8 bit)
3233 tca6408 Select the TI TCA6408 (8 bit)
3234 tca6416 Select the TI TCA6416 (16 bit)
3235 tca6424 Select the TI TCA6424 (24 bit)
3236 tca9539 Select the TI TCA9539 (16 bit)
3237 tca9554 Select the TI TCA9554 (8 bit)
3238 cat9554 Select the Onnn CAT9554 (8 bit)
3239 pca9654 Select the Onnn PCA9654 (8 bit)
3240 xra1202 Select the Exar XRA1202 (8 bit)
3244 Info: NXP PCF857x family of I2C GPIO expanders.
3245 Load: dtoverlay=pcf857x,<param>=<val>
3246 Params: addr I2C address of expander. Default
3247 depends on model selected.
3248 pcf8574 Select the NXP PCF8574 (8 bit)
3249 pcf8574a Select the NXP PCF8574A (8 bit)
3250 pcf8575 Select the NXP PCF8575 (16 bit)
3251 pca8574 Select the NXP PCA8574 (8 bit)
3254 Name: pcie-32bit-dma
3255 Info: Force PCIe config to support 32bit DMA addresses at the expense of
3256 having to bounce buffers.
3257 Load: dtoverlay=pcie-32bit-dma
3261 [ The pcf2127-rtc overlay has been deleted. See i2c-rtc. ]
3264 [ The pcf8523-rtc overlay has been deleted. See i2c-rtc. ]
3267 [ The pcf8563-rtc overlay has been deleted. See i2c-rtc. ]
3271 Info: This overlay has been renamed act-led, keeping pi3-act-led as an alias
3272 for backwards compatibility.
3276 Name: pi3-disable-bt
3277 Info: This overlay has been renamed disable-bt, keeping pi3-disable-bt as an
3278 alias for backwards compatibility.
3282 Name: pi3-disable-wifi
3283 Info: This overlay has been renamed disable-wifi, keeping pi3-disable-wifi as
3284 an alias for backwards compatibility.
3288 Name: pi3-miniuart-bt
3289 Info: This overlay has been renamed miniuart-bt, keeping pi3-miniuart-bt as
3290 an alias for backwards compatibility.
3295 Info: Configures the pibell audio card.
3296 Load: dtoverlay=pibell,<param>=<val>
3297 Params: alsaname Set the name as it appears in ALSA (default
3302 Info: Configures the PiFace Digital mcp23s17 GPIO port expander.
3303 Load: dtoverlay=pifacedigital,<param>=<val>
3304 Params: spi-present-mask 8-bit integer, bitmap indicating MCP23S17 SPI0
3305 CS0 address. PiFace Digital supports addresses
3306 0-3, which can be configured with JP1 and JP2.
3310 Info: Configures the PiFi 40W stereo amplifier
3311 Load: dtoverlay=pifi-40
3316 Info: Configures the PiFi DAC HD
3317 Load: dtoverlay=pifi-dac-hd
3322 Info: Configures the PiFi DAC Zero
3323 Load: dtoverlay=pifi-dac-zero
3328 Info: Configures the PiFi Mini stereo amplifier
3329 Load: dtoverlay=pifi-mini-210
3334 Info: Configures the PiGlow by pimoroni.com
3335 Load: dtoverlay=piglow
3340 Info: PiScreen display by OzzMaker.com
3341 Load: dtoverlay=piscreen,<param>=<val>
3342 Params: speed Display SPI bus speed
3344 rotate Display rotation {0,90,180,270}
3346 fps Delay between frame updates
3348 debug Debug output level {0-7}
3350 xohms Touchpanel sensitivity (X-plate resistance)
3352 drm Select the DRM/KMS driver instead of the FBTFT
3357 Info: PiScreen 2 with resistive TP display by OzzMaker.com
3358 Load: dtoverlay=piscreen2r,<param>=<val>
3359 Params: speed Display SPI bus speed
3361 rotate Display rotation {0,90,180,270}
3363 fps Delay between frame updates
3365 debug Debug output level {0-7}
3367 xohms Touchpanel sensitivity (X-plate resistance)
3371 Info: Configures the Blokas Labs pisound card
3372 Load: dtoverlay=pisound
3377 Info: Adafruit PiTFT 2.2" screen
3378 Load: dtoverlay=pitft22,<param>=<val>
3379 Params: speed Display SPI bus speed
3381 rotate Display rotation {0,90,180,270}
3383 fps Delay between frame updates
3385 debug Debug output level {0-7}
3388 Name: pitft28-capacitive
3389 Info: Adafruit PiTFT 2.8" capacitive touch screen
3390 Load: dtoverlay=pitft28-capacitive,<param>=<val>
3391 Params: speed Display SPI bus speed
3393 rotate Display rotation {0,90,180,270}
3395 fps Delay between frame updates
3397 debug Debug output level {0-7}
3399 touch-sizex Touchscreen size x (default 240)
3401 touch-sizey Touchscreen size y (default 320)
3403 touch-invx Touchscreen inverted x axis
3405 touch-invy Touchscreen inverted y axis
3407 touch-swapxy Touchscreen swapped x y axis
3410 Name: pitft28-resistive
3411 Info: Adafruit PiTFT 2.8" resistive touch screen
3412 Load: dtoverlay=pitft28-resistive,<param>=<val>
3413 Params: speed Display SPI bus speed
3415 rotate Display rotation {0,90,180,270}
3417 fps Delay between frame updates
3419 debug Debug output level {0-7}
3421 drm Force the use of the mi0283qt DRM driver (by
3422 default the ili9340 framebuffer driver will
3423 be used in preference if available)
3426 Name: pitft35-resistive
3427 Info: Adafruit PiTFT 3.5" resistive touch screen
3428 Load: dtoverlay=pitft35-resistive,<param>=<val>
3429 Params: speed Display SPI bus speed
3431 rotate Display rotation {0,90,180,270}
3433 fps Delay between frame updates
3435 debug Debug output level {0-7}
3437 drm Force the use of the hx8357d DRM driver (by
3438 default the fb_hx8357d framebuffer driver will
3439 be used in preference if available)
3443 Info: Configures the pps-gpio (pulse-per-second time signal via GPIO).
3444 Load: dtoverlay=pps-gpio,<param>=<val>
3445 Params: gpiopin Input GPIO (default "18")
3446 assert_falling_edge When present, assert is indicated by a falling
3447 edge, rather than by a rising edge (default
3449 capture_clear Generate clear events on the trailing edge
3451 pull Desired pull-up/down state (off, down, up)
3456 Info: Configures the PROTO Audio Codec card
3457 Load: dtoverlay=proto-codec
3462 Info: Configures a single PWM channel
3463 Legal pin,function combinations for each channel:
3464 PWM0: 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3465 PWM1: 13,4(Alt0) 19,2(Alt5) 41,4(Alt0) 45,4(Alt0) 53,5(Alt1)
3467 1) Pin 18 is the only one available on all platforms, and
3468 it is the one used by the I2S audio interface.
3469 Pins 12 and 13 might be better choices on an A+, B+ or Pi2.
3470 2) The onboard analogue audio output uses both PWM channels.
3471 3) So be careful mixing audio and PWM.
3472 4) Currently the clock must have been enabled and configured
3474 Load: dtoverlay=pwm,<param>=<val>
3475 Params: pin Output pin (default 18) - see table
3476 func Pin function (default 2 = Alt5) - see above
3477 clock PWM clock frequency (informational)
3481 Info: Configures both PWM channels
3482 Legal pin,function combinations for each channel:
3483 PWM0: 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3484 PWM1: 13,4(Alt0) 19,2(Alt5) 41,4(Alt0) 45,4(Alt0) 53,5(Alt1)
3486 1) Pin 18 is the only one available on all platforms, and
3487 it is the one used by the I2S audio interface.
3488 Pins 12 and 13 might be better choices on an A+, B+ or Pi2.
3489 2) The onboard analogue audio output uses both PWM channels.
3490 3) So be careful mixing audio and PWM.
3491 4) Currently the clock must have been enabled and configured
3493 Load: dtoverlay=pwm-2chan,<param>=<val>
3494 Params: pin Output pin (default 18) - see table
3495 pin2 Output pin for other channel (default 19)
3496 func Pin function (default 2 = Alt5) - see above
3497 func2 Function for pin2 (default 2 = Alt5)
3498 clock PWM clock frequency (informational)
3502 Info: Use GPIO pin as pwm-assisted infrared transmitter output.
3503 This is an alternative to "gpio-ir-tx". pwm-ir-tx makes use
3504 of PWM0 to reduce the CPU load during transmission compared to
3505 gpio-ir-tx which uses bit-banging.
3506 Legal pin,function combinations are:
3507 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3508 Load: dtoverlay=pwm-ir-tx,<param>=<val>
3509 Params: gpio_pin Output GPIO (default 18)
3511 func Pin function (default 2 = Alt5)
3515 Info: Configures one or two PWM channel on PWM1 (BCM2711 only)
3517 1) The onboard analogue audio output uses both PWM channels.
3518 2) So be careful mixing audio and PWM.
3519 Note that even when only one pin is enabled, both channels are available
3520 from the PWM driver, so be careful to use the correct one.
3521 Load: dtoverlay=pwm1,<param>=<val>
3522 Params: clock PWM clock frequency (informational)
3523 pins_40 Enable channel 0 (PWM1_0) on GPIO 40
3524 pins_41 Enable channel 1 (PWM1_1) on GPIO 41
3525 pins_40_41 Enable channels 0 (PWM1_0) and 1 (PW1_1) on
3526 GPIOs 40 and 41 (default)
3527 pull_up Enable pull-ups on the PWM pins (default)
3528 pull_down Enable pull-downs on the PWM pins
3529 pull_off Disable pulls on the PWM pins
3533 Info: in-tech's Evaluation Board for PLC Stamp micro
3534 This uses spi0 and a separate GPIO interrupt to connect the QCA7000.
3535 Load: dtoverlay=qca7000,<param>=<val>
3536 Params: int_pin GPIO pin for interrupt signal (default 23)
3538 speed SPI bus speed (default 12 MHz)
3542 Info: in-tech's Evaluation Board for PLC Stamp micro (UART)
3543 This uses uart0/ttyAMA0 over GPIOs 14 & 15 to connect the QCA7000.
3544 But it requires disabling of onboard Bluetooth on
3545 Pi 3B, 3B+, 3A+, 4B and Zero W.
3546 Load: dtoverlay=qca7000-uart0,<param>=<val>
3547 Params: baudrate Set the baudrate for the UART (default
3552 Info: Enable the preservation of crash logs across a reboot. With
3553 systemd-pstore enabled (as it is on Raspberry Pi OS) the crash logs
3554 are moved to /var/lib/systemd/pstore/ on reboot.
3555 Load: dtoverlay=ramoops,<param>=<val>
3556 Params: base-addr Where to place the capture buffer (default
3558 total-size How much memory to allocate altogether (in
3559 bytes - default 64kB)
3560 record-size How much space to use for each capture, i.e.
3561 total-size / record-size = number of captures
3563 console-size Size of non-panic dmesg captures (default 0)
3567 Info: The version of the ramoops overlay for the Pi 4 family. It should be
3568 loaded automatically if dtoverlay=ramoops is specified on a Pi 4.
3569 Load: dtoverlay=ramoops-pi4,<param>=<val>
3570 Params: base-addr Where to place the capture buffer (default
3572 total-size How much memory to allocate altogether (in
3573 bytes - default 64kB)
3574 record-size How much space to use for each capture, i.e.
3575 total-size / record-size = number of captures
3577 console-size Size of non-panic dmesg captures (default 0)
3580 Name: rotary-encoder
3581 Info: Overlay for GPIO connected rotary encoder.
3582 Load: dtoverlay=rotary-encoder,<param>=<val>
3583 Params: pin_a GPIO connected to rotary encoder channel A
3585 pin_b GPIO connected to rotary encoder channel B
3587 relative_axis register a relative axis rather than an
3588 absolute one. Relative axis will only
3589 generate +1/-1 events on the input device,
3590 hence no steps need to be passed.
3591 linux_axis the input subsystem axis to map to this
3592 rotary encoder. Defaults to 0 (ABS_X / REL_X)
3593 rollover Automatic rollover when the rotary value
3594 becomes greater than the specified steps or
3595 smaller than 0. For absolute axis only.
3596 steps-per-period Number of steps (stable states) per period.
3597 The values have the following meaning:
3598 1: Full-period mode (default)
3600 4: Quarter-period mode
3601 steps Number of steps in a full turnaround of the
3602 encoder. Only relevant for absolute axis.
3603 Defaults to 24 which is a typical value for
3605 wakeup Boolean, rotary encoder can wake up the
3607 encoding String, the method used to encode steps.
3608 Supported are "gray" (the default and more
3609 common) and "binary".
3613 Info: Raspberry Pi official display backlight driver
3614 Load: dtoverlay=rpi-backlight
3618 Name: rpi-cirrus-wm5102
3619 Info: This overlay has been renamed to cirrus-wm5102
3624 Info: Configures the Raspberry Pi Codec Zero sound card
3625 Load: dtoverlay=rpi-codeczero
3630 Info: This overlay has been renamed to i2s-dac.
3635 Info: Configures the Raspberry Pi DAC+ card
3636 Load: dtoverlay=rpi-dacplus,<param>=<val>
3637 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3638 digital volume control. Enable by adding
3639 "dtparam=24db_digital_gain" to config.txt
3640 before any "dtoverlay" lines.
3641 The default behaviour is that the digital
3642 volume control is limited to a maximum of
3643 0dB. ie. it can attenuate but not provide
3644 gain. For most users, this will be desired
3645 as it will prevent clipping. By appending
3646 the 24db_digital_gain parameter, the digital
3647 volume control will allow up to 24dB of
3648 gain. If this parameter is enabled, it is the
3649 responsibility of the user to ensure that
3650 the digital volume control is set to a value
3651 that does not result in clipping/distortion!
3655 Info: Configures the Raspberry Pi DAC Pro sound card
3656 Load: dtoverlay=rpi-dacpro,<param>=<val>
3657 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3658 digital volume control. Enable by adding
3659 "dtparam=24db_digital_gain" to config.txt
3660 before any "dtoverlay" lines.
3661 The default behaviour is that the digital
3662 volume control is limited to a maximum of
3663 0dB. ie. it can attenuate but not provide
3664 gain. For most users, this will be desired
3665 as it will prevent clipping. By appending
3666 the 24db_digital_gain parameter, the digital
3667 volume control will allow up to 24dB of
3668 gain. If this parameter is enabled, it is the
3669 responsibility of the user to ensure that
3670 the digital volume control is set to a value
3671 that does not result in clipping/distortion!
3674 Name: rpi-digiampplus
3675 Info: Configures the Raspberry Pi DigiAMP+ sound card
3676 Load: dtoverlay=rpi-digiampplus,<param>=<val>
3677 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3678 digital volume control. Enable by adding
3679 "dtparam=24db_digital_gain" to config.txt
3680 before any "dtoverlay" lines.
3681 The default behaviour is that the digital
3682 volume control is limited to a maximum of
3683 0dB. ie. it can attenuate but not provide
3684 gain. For most users, this will be desired
3685 as it will prevent clipping. By appending
3686 the 24db_digital_gain parameter, the digital
3687 volume control will allow up to 24dB of
3688 gain. If this parameter is enabled, it is the
3689 responsibility of the user to ensure that
3690 the digital volume control is set to a value
3691 that does not result in clipping/distortion!
3692 auto_mute_amp If specified, unmute/mute the DigiAMP+ when
3693 starting/stopping audio playback (default "on").
3694 unmute_amp If specified, unmute the DigiAMP+ amp once when
3695 the DAC driver module loads (default "off").
3699 Info: This overlay has been renamed to watterott-display
3704 Info: Official Raspberry Pi display touchscreen
3705 Load: dtoverlay=rpi-ft5406,<param>=<val>
3706 Params: touchscreen-size-x Touchscreen X resolution (default 800)
3707 touchscreen-size-y Touchscreen Y resolution (default 600);
3708 touchscreen-inverted-x Invert touchscreen X coordinates (default 0);
3709 touchscreen-inverted-y Invert touchscreen Y coordinates (default 0);
3710 touchscreen-swapped-x-y Swap X and Y cordinates (default 0);
3714 Info: Raspberry Pi PoE HAT fan
3715 Load: dtoverlay=rpi-poe,<param>[=<val>]
3716 Params: poe_fan_temp0 Temperature (in millicelcius) at which the fan
3717 turns on (default 40000)
3718 poe_fan_temp0_hyst Temperature delta (in millicelcius) at which
3719 the fan turns off (default 2000)
3720 poe_fan_temp1 Temperature (in millicelcius) at which the fan
3721 speeds up (default 45000)
3722 poe_fan_temp1_hyst Temperature delta (in millicelcius) at which
3723 the fan slows down (default 2000)
3724 poe_fan_temp2 Temperature (in millicelcius) at which the fan
3725 speeds up (default 50000)
3726 poe_fan_temp2_hyst Temperature delta (in millicelcius) at which
3727 the fan slows down (default 2000)
3728 poe_fan_temp3 Temperature (in millicelcius) at which the fan
3729 speeds up (default 55000)
3730 poe_fan_temp3_hyst Temperature delta (in millicelcius) at which
3731 the fan slows down (default 5000)
3732 i2c Control the fan via Linux I2C drivers instead of
3737 Info: Raspberry Pi PoE+ HAT fan
3738 Load: dtoverlay=rpi-poe-plus,<param>[=<val>]
3739 Params: poe_fan_temp0 Temperature (in millicelcius) at which the fan
3740 turns on (default 40000)
3741 poe_fan_temp0_hyst Temperature delta (in millicelcius) at which
3742 the fan turns off (default 2000)
3743 poe_fan_temp1 Temperature (in millicelcius) at which the fan
3744 speeds up (default 45000)
3745 poe_fan_temp1_hyst Temperature delta (in millicelcius) at which
3746 the fan slows down (default 2000)
3747 poe_fan_temp2 Temperature (in millicelcius) at which the fan
3748 speeds up (default 50000)
3749 poe_fan_temp2_hyst Temperature delta (in millicelcius) at which
3750 the fan slows down (default 2000)
3751 poe_fan_temp3 Temperature (in millicelcius) at which the fan
3752 speeds up (default 55000)
3753 poe_fan_temp3_hyst Temperature delta (in millicelcius) at which
3754 the fan slows down (default 5000)
3755 i2c Control the fan via Linux I2C drivers instead of
3760 Info: This overlay has been renamed to proto-codec.
3765 Info: Raspberry Pi Sense HAT
3766 Load: dtoverlay=rpi-sense
3771 Info: Raspberry Pi Sense HAT v2
3772 Load: dtoverlay=rpi-sense-v2
3777 Info: Raspberry Pi TV HAT
3778 Load: dtoverlay=rpi-tv
3783 Info: This overlay has been deprecated and deleted as the V4L2 stateless
3784 video decoder driver is enabled by default.
3788 Name: rra-digidac1-wm8741-audio
3789 Info: Configures the Red Rocks Audio DigiDAC1 soundcard
3790 Load: dtoverlay=rra-digidac1-wm8741-audio
3795 Info: Overlay for the SPI-connected Sainsmart 1.8" display (based on the
3797 Load: dtoverlay=sainsmart18,<param>=<val>
3798 Params: rotate Display rotation {0,90,180,270}
3799 speed SPI bus speed in Hz (default 4000000)
3800 fps Display frame rate in Hz
3801 bgr Enable BGR mode (default off)
3802 debug Debug output level {0-7}
3803 dc_pin GPIO pin for D/C (default 24)
3804 reset_pin GPIO pin for RESET (default 25)
3808 Info: Overlay for the NXP SC16IS750 UART with I2C Interface
3809 Enables the chip on I2C1 at 0x48 (or the "addr" parameter value). To
3810 select another address, please refer to table 10 in reference manual.
3811 Load: dtoverlay=sc16is750-i2c,<param>=<val>
3812 Params: int_pin GPIO used for IRQ (default 24)
3813 addr Address (default 0x48)
3814 xtal On-board crystal frequency (default 14745600)
3818 Info: Overlay for the NXP SC16IS752 dual UART with I2C Interface
3819 Enables the chip on I2C1 at 0x48 (or the "addr" parameter value). To
3820 select another address, please refer to table 10 in reference manual.
3821 Load: dtoverlay=sc16is752-i2c,<param>=<val>
3822 Params: int_pin GPIO used for IRQ (default 24)
3823 addr Address (default 0x48)
3824 xtal On-board crystal frequency (default 14745600)
3827 Name: sc16is752-spi0
3828 Info: Overlay for the NXP SC16IS752 Dual UART with SPI Interface
3829 Enables the chip on SPI0.
3830 Load: dtoverlay=sc16is752-spi0,<param>=<val>
3831 Params: int_pin GPIO used for IRQ (default 24)
3832 xtal On-board crystal frequency (default 14745600)
3835 Name: sc16is752-spi1
3836 Info: Overlay for the NXP SC16IS752 Dual UART with SPI Interface
3837 Enables the chip on SPI1.
3838 N.B.: spi1 is only accessible on devices with a 40pin header, eg:
3839 A+, B+, Zero and PI2 B; as well as the Compute Module.
3841 Load: dtoverlay=sc16is752-spi1,<param>=<val>
3842 Params: int_pin GPIO used for IRQ (default 24)
3843 xtal On-board crystal frequency (default 14745600)
3847 Info: Selects the bcm2835-sdhost SD/MMC driver, optionally with overclock.
3848 N.B. This overlay is designed for situations where the mmc driver is
3849 the default, so it disables the other (mmc) interface - this will kill
3850 WLAN on a Pi3. If this isn't what you want, either use the sdtweak
3851 overlay or the new sd_* dtparams of the base DTBs.
3852 Load: dtoverlay=sdhost,<param>=<val>
3853 Params: overclock_50 Clock (in MHz) to use when the MMC framework
3856 force_pio Disable DMA support (default off)
3858 pio_limit Number of blocks above which to use DMA
3861 debug Enable debug output (default off)
3865 Info: Selects the bcm2835-sdhost SD/MMC driver, optionally with overclock,
3866 and enables SDIO via GPIOs 22-27. An example of use in 1-bit mode is
3867 "dtoverlay=sdio,bus_width=1,gpios_22_25"
3868 Load: dtoverlay=sdio,<param>=<val>
3869 Params: sdio_overclock SDIO Clock (in MHz) to use when the MMC
3870 framework requests 50MHz
3872 poll_once Disable SDIO-device polling every second
3873 (default on: polling once at boot-time)
3875 bus_width Set the SDIO host bus width (default 4 bits)
3877 gpios_22_25 Select GPIOs 22-25 for 1-bit mode. Must be used
3878 with bus_width=1. This replaces the sdio-1bit
3879 overlay, which is now deprecated.
3881 gpios_34_37 Select GPIOs 34-37 for 1-bit mode. Must be used
3884 gpios_34_39 Select GPIOs 34-39 for 4-bit mode. Must be used
3885 with bus_width=4 (the default).
3889 Info: This overlay is now deprecated. Use
3890 "dtoverlay=sdio,bus_width=1,gpios_22_25" instead.
3895 Info: This overlay is now deprecated. Use the sd_* dtparams in the
3896 base DTB, e.g. "dtoverlay=sdtweak,poll_once" becomes
3897 "dtparam=sd_poll_once".
3901 Name: seeed-can-fd-hat-v1
3902 Info: Overlay for Seeed Studio CAN BUS FD HAT with two CAN FD
3903 channels without RTC. Use this overlay if your HAT has no
3905 https://www.seeedstudio.com/2-Channel-CAN-BUS-FD-Shield-for-Raspberry-Pi-p-4072.html
3906 Load: dtoverlay=seeed-can-fd-hat-v1
3910 Name: seeed-can-fd-hat-v2
3911 Info: Overlay for Seeed Studio CAN BUS FD HAT with two CAN FD
3912 channels and an RTC. Use this overlay if your HAT has a
3914 https://www.seeedstudio.com/CAN-BUS-FD-HAT-for-Raspberry-Pi-p-4742.html
3915 Load: dtoverlay=seeed-can-fd-hat-v2
3920 Info: Overlay for SH1106 OLED via SPI using fbtft staging driver.
3921 Load: dtoverlay=sh1106-spi,<param>=<val>
3922 Params: speed SPI bus speed (default 4000000)
3923 rotate Display rotation (0, 90, 180 or 270; default 0)
3924 fps Delay between frame updates (default 25)
3925 debug Debug output level (0-7; default 0)
3926 dc_pin GPIO pin for D/C (default 24)
3927 reset_pin GPIO pin for RESET (default 25)
3928 height Display height (32 or 64; default 64)
3932 Info: Overlay for Si446x UHF Transceiver via SPI using si446x driver.
3933 The driver is currently out-of-tree at
3934 https://github.com/sunipkmukherjee/silabs.git
3935 Load: dtoverlay=si446x-spi0,<param>=<val>
3936 Params: speed SPI bus speed (default 4000000)
3937 int_pin GPIO pin for interrupts (default 17)
3938 reset_pin GPIO pin for RESET (default 27)
3942 Info: Enables the Secondary Memory Interface peripheral. Uses GPIOs 2-25!
3948 Info: Enables the userspace interface for the SMI driver
3949 Load: dtoverlay=smi-dev
3954 Info: Enables access to NAND flash via the SMI interface
3955 Load: dtoverlay=smi-nand
3960 Info: Move SPI function block to GPIO 35 to 39
3961 Load: dtoverlay=spi-gpio35-39
3966 Info: Move SPI function block to GPIOs 40 to 45
3967 Load: dtoverlay=spi-gpio40-45
3972 Info: Adds support for a number of SPI Real Time Clock devices
3973 Load: dtoverlay=spi-rtc,<param>=<val>
3974 Params: ds3232 Select the DS3232 device
3975 ds3234 Select the DS3234 device
3976 pcf2123 Select the PCF2123 device
3978 spi0_0 Use spi0.0 (default)
3984 cs_high This device requires an active-high CS
3988 Info: Don't claim any CS pins for SPI0. Requires a device with its chip
3989 select permanently enabled, but frees a GPIO for e.g. a DPI display.
3990 Load: dtoverlay=spi0-0cs,<param>=<val>
3991 Params: no_miso Don't claim and use the MISO pin (9), freeing
3996 Info: Only use one CS pin for SPI0
3997 Load: dtoverlay=spi0-1cs,<param>=<val>
3998 Params: cs0_pin GPIO pin for CS0 (default 8)
3999 no_miso Don't claim and use the MISO pin (9), freeing
4004 Info: Change the CS pins for SPI0
4005 Load: dtoverlay=spi0-2cs,<param>=<val>
4006 Params: cs0_pin GPIO pin for CS0 (default 8)
4007 cs1_pin GPIO pin for CS1 (default 7)
4008 no_miso Don't claim and use the MISO pin (9), freeing
4013 Info: This overlay has been renamed spi0-2cs, keeping spi0-cs as an
4014 alias for backwards compatibility.
4019 Info: This overlay has been deprecated and removed because it is no longer
4020 necessary and has been seen to prevent spi0 from working.
4025 Info: Enables spi1 with a single chip select (CS) line and associated spidev
4026 dev node. The gpio pin number for the CS line and spidev device node
4027 creation are configurable.
4028 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4029 Load: dtoverlay=spi1-1cs,<param>=<val>
4030 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4031 cs0_spidev Set to 'off' to stop the creation of a
4032 userspace device node /dev/spidev1.0 (default
4033 is 'on' or enabled).
4037 Info: Enables spi1 with two chip select (CS) lines and associated spidev
4038 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4039 creation are configurable.
4040 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4041 Load: dtoverlay=spi1-2cs,<param>=<val>
4042 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4043 cs1_pin GPIO pin for CS1 (default 17 - BCM SPI1_CE1).
4044 cs0_spidev Set to 'off' to stop the creation of a
4045 userspace device node /dev/spidev1.0 (default
4046 is 'on' or enabled).
4047 cs1_spidev Set to 'off' to stop the creation of a
4048 userspace device node /dev/spidev1.1 (default
4049 is 'on' or enabled).
4053 Info: Enables spi1 with three chip select (CS) lines and associated spidev
4054 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4055 creation are configurable.
4056 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4057 Load: dtoverlay=spi1-3cs,<param>=<val>
4058 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4059 cs1_pin GPIO pin for CS1 (default 17 - BCM SPI1_CE1).
4060 cs2_pin GPIO pin for CS2 (default 16 - BCM SPI1_CE2).
4061 cs0_spidev Set to 'off' to stop the creation of a
4062 userspace device node /dev/spidev1.0 (default
4063 is 'on' or enabled).
4064 cs1_spidev Set to 'off' to stop the creation of a
4065 userspace device node /dev/spidev1.1 (default
4066 is 'on' or enabled).
4067 cs2_spidev Set to 'off' to stop the creation of a
4068 userspace device node /dev/spidev1.2 (default
4069 is 'on' or enabled).
4073 Info: Enables spi2 on GPIOs 40-42 with a single chip select (CS) line and
4074 associated spidev dev node. The gpio pin number for the CS line and
4075 spidev device node creation are configurable. spi2-2cs-pi5 is
4076 substituted on a Pi 5.
4077 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4078 Load: dtoverlay=spi2-1cs,<param>=<val>
4079 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4080 cs0_spidev Set to 'off' to stop the creation of a
4081 userspace device node /dev/spidev2.0 (default
4082 is 'on' or enabled).
4086 Info: Enables spi2 on GPIOs 1-3 with a single chip select (CS) line and
4087 associated spidev dev node. The gpio pin number for the CS line and
4088 spidev device node creation are configurable. Pi 5 only.
4089 Load: dtoverlay=spi2-1cs-pi5,<param>=<val>
4090 Params: cs0_pin GPIO pin for CS0 (default 0).
4091 cs0_spidev Set to 'off' to stop the creation of a
4092 userspace device node /dev/spidev2.0 (default
4093 is 'on' or enabled).
4097 Info: Enables spi2 on GPIOs 40-42 with two chip select (CS) lines and
4098 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4099 spidev device node creation are configurable. spi2-2cs-pi5 is
4100 substituted on a Pi 5.
4101 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4102 Load: dtoverlay=spi2-2cs,<param>=<val>
4103 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4104 cs1_pin GPIO pin for CS1 (default 44 - BCM SPI2_CE1).
4105 cs0_spidev Set to 'off' to stop the creation of a
4106 userspace device node /dev/spidev2.0 (default
4107 is 'on' or enabled).
4108 cs1_spidev Set to 'off' to stop the creation of a
4109 userspace device node /dev/spidev2.1 (default
4110 is 'on' or enabled).
4114 Info: Enables spi2 on GPIOs 1-3 with two chip select (CS) lines and
4115 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4116 spidev device node creation are configurable. Pi 5 only.
4117 Load: dtoverlay=spi2-2cs-pi5,<param>=<val>
4118 Params: cs0_pin GPIO pin for CS0 (default 0).
4119 cs1_pin GPIO pin for CS1 (default 24).
4120 cs0_spidev Set to 'off' to stop the creation of a
4121 userspace device node /dev/spidev2.0 (default
4122 is 'on' or enabled).
4123 cs1_spidev Set to 'off' to stop the creation of a
4124 userspace device node /dev/spidev2.1 (default
4125 is 'on' or enabled).
4129 Info: Enables spi2 on GPIOs 40-42 with three chip select (CS) lines and
4130 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4131 spidev device node creation are configurable.
4132 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4133 Load: dtoverlay=spi2-3cs,<param>=<val>
4134 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4135 cs1_pin GPIO pin for CS1 (default 44 - BCM SPI2_CE1).
4136 cs2_pin GPIO pin for CS2 (default 45 - BCM SPI2_CE2).
4137 cs0_spidev Set to 'off' to stop the creation of a
4138 userspace device node /dev/spidev2.0 (default
4139 is 'on' or enabled).
4140 cs1_spidev Set to 'off' to stop the creation of a
4141 userspace device node /dev/spidev2.1 (default
4142 is 'on' or enabled).
4143 cs2_spidev Set to 'off' to stop the creation of a
4144 userspace device node /dev/spidev2.2 (default
4145 is 'on' or enabled).
4149 Info: Enables spi3 on GPIOs 1-3 with a single chip select (CS) line and
4150 associated spidev dev node. The gpio pin number for the CS line and
4151 spidev device node creation are configurable. BCM2711 only,
4152 spi3-1cs-pi5 is substituted on Pi 5.
4153 Load: dtoverlay=spi3-1cs,<param>=<val>
4154 Params: cs0_pin GPIO pin for CS0 (default 0 - BCM SPI3_CE0).
4155 cs0_spidev Set to 'off' to prevent the creation of a
4156 userspace device node /dev/spidev3.0 (default
4157 is 'on' or enabled).
4161 Info: Enables spi3 on GPIOs 5-7 with a single chip select (CS) line and
4162 associated spidev dev node. The gpio pin number for the CS line and
4163 spidev device node creation are configurable. Pi 5 only.
4164 Load: dtoverlay=spi3-1cs-pi5,<param>=<val>
4165 Params: cs0_pin GPIO pin for CS0 (default 4).
4166 cs0_spidev Set to 'off' to prevent the creation of a
4167 userspace device node /dev/spidev3.0 (default
4168 is 'on' or enabled).
4172 Info: Enables spi3 on GPIO2 1-3 with two chip select (CS) lines and
4173 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4174 spidev device node creation are configurable. BCM2711 only,
4175 spi3-2cs-pi5 is substituted on Pi 5.
4176 Load: dtoverlay=spi3-2cs,<param>=<val>
4177 Params: cs0_pin GPIO pin for CS0 (default 0 - BCM SPI3_CE0).
4178 cs1_pin GPIO pin for CS1 (default 24 - BCM SPI3_CE1).
4179 cs0_spidev Set to 'off' to prevent the creation of a
4180 userspace device node /dev/spidev3.0 (default
4181 is 'on' or enabled).
4182 cs1_spidev Set to 'off' to prevent the creation of a
4183 userspace device node /dev/spidev3.1 (default
4184 is 'on' or enabled).
4188 Info: Enables spi3 on GPIOs 5-7 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. Pi 5 only.
4191 Load: dtoverlay=spi3-2cs-pi5,<param>=<val>
4192 Params: cs0_pin GPIO pin for CS0 (default 4).
4193 cs1_pin GPIO pin for CS1 (default 25).
4194 cs0_spidev Set to 'off' to prevent the creation of a
4195 userspace device node /dev/spidev3.0 (default
4196 is 'on' or enabled).
4197 cs1_spidev Set to 'off' to prevent the creation of a
4198 userspace device node /dev/spidev3.1 (default
4199 is 'on' or enabled).
4203 Info: Enables spi4 on GPIOs 5-7 with a single chip select (CS) line and
4204 associated spidev dev node. The gpio pin number for the CS line and
4205 spidev device node creation are configurable. BCM2711 only.
4206 Load: dtoverlay=spi4-1cs,<param>=<val>
4207 Params: cs0_pin GPIO pin for CS0 (default 4 - BCM SPI4_CE0).
4208 cs0_spidev Set to 'off' to prevent the creation of a
4209 userspace device node /dev/spidev4.0 (default
4210 is 'on' or enabled).
4214 Info: Enables spi4 on GPIOs 5-6 with two chip select (CS) lines and
4215 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4216 spidev device node creation are configurable. BCM2711 only.
4217 Load: dtoverlay=spi4-2cs,<param>=<val>
4218 Params: cs0_pin GPIO pin for CS0 (default 4 - BCM SPI4_CE0).
4219 cs1_pin GPIO pin for CS1 (default 25 - BCM SPI4_CE1).
4220 cs0_spidev Set to 'off' to prevent the creation of a
4221 userspace device node /dev/spidev4.0 (default
4222 is 'on' or enabled).
4223 cs1_spidev Set to 'off' to prevent the creation of a
4224 userspace device node /dev/spidev4.1 (default
4225 is 'on' or enabled).
4229 Info: Enables spi5 on GPIOs 13-15 with a single chip select (CS) line and
4230 associated spidev dev node. The gpio pin numbers for the CS lines and
4231 spidev device node creation are configurable. BCM2711 and Pi 5.
4232 Load: dtoverlay=spi5-1cs,<param>=<val>
4233 Params: cs0_pin GPIO pin for CS0 (default 12).
4234 cs0_spidev Set to 'off' to prevent the creation of a
4235 userspace device node /dev/spidev5.0 (default
4236 is 'on' or enabled).
4244 Info: Enables spi5 on GPIOs 13-15 with two chip select (CS) lines and
4245 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4246 spidev device node creation are configurable. BCM2711 and Pi 5.
4247 Load: dtoverlay=spi5-2cs,<param>=<val>
4248 Params: cs0_pin GPIO pin for CS0 (default 12).
4249 cs1_pin GPIO pin for CS1 (default 26).
4250 cs0_spidev Set to 'off' to prevent the creation of a
4251 userspace device node /dev/spidev5.0 (default
4252 is 'on' or enabled).
4253 cs1_spidev Set to 'off' to prevent the creation of a
4254 userspace device node /dev/spidev5.1 (default
4255 is 'on' or enabled).
4263 Info: Enables spi6 with a single chip select (CS) line and associated spidev
4264 dev node. The gpio pin number for the CS line and spidev device node
4265 creation are configurable. BCM2711 only.
4266 Load: dtoverlay=spi6-1cs,<param>=<val>
4267 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI6_CE0).
4268 cs0_spidev Set to 'off' to prevent the creation of a
4269 userspace device node /dev/spidev6.0 (default
4270 is 'on' or enabled).
4274 Info: Enables spi6 with two chip select (CS) lines and associated spidev
4275 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4276 creation are configurable. BCM2711 only.
4277 Load: dtoverlay=spi6-2cs,<param>=<val>
4278 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI6_CE0).
4279 cs1_pin GPIO pin for CS1 (default 27 - BCM SPI6_CE1).
4280 cs0_spidev Set to 'off' to prevent the creation of a
4281 userspace device node /dev/spidev6.0 (default
4282 is 'on' or enabled).
4283 cs1_spidev Set to 'off' to prevent the creation of a
4284 userspace device node /dev/spidev6.1 (default
4285 is 'on' or enabled).
4289 Info: Overlay for activation of SSD1306 over I2C OLED display framebuffer.
4290 Load: dtoverlay=ssd1306,<param>=<val>
4291 Params: address Location in display memory of first character.
4293 width Width of display. (default=128)
4294 height Height of display. (default=64)
4295 offset virtual channel a. (default=0)
4296 normal Has no effect on displays tested. (default=not
4298 sequential Set this if every other scan line is missing.
4300 remapped Set this if display is garbled. (default=not
4302 inverted Set this if display is inverted and mirrored.
4306 Typical usage for 128x64 display: dtoverlay=ssd1306,inverted
4308 Typical usage for 128x32 display: dtoverlay=ssd1306,inverted,sequential
4310 i2c_baudrate=400000 will speed up the display.
4312 i2c_baudrate=1000000 seems to work even though it's not officially
4313 supported by the hardware, and is faster still.
4315 For more information refer to the device datasheet at:
4316 https://cdn-shop.adafruit.com/datasheets/SSD1306.pdf
4320 Info: Overlay for SSD1306 OLED via SPI using fbtft staging driver.
4321 Load: dtoverlay=ssd1306-spi,<param>=<val>
4322 Params: speed SPI bus speed (default 10000000)
4323 rotate Display rotation (0, 90, 180 or 270; default 0)
4324 fps Delay between frame updates (default 25)
4325 debug Debug output level (0-7; default 0)
4326 dc_pin GPIO pin for D/C (default 24)
4327 reset_pin GPIO pin for RESET (default 25)
4328 height Display height (32 or 64; default 64)
4329 inverted Set this if display is inverted and mirrored.
4334 Info: Overlay for SSD1331 OLED via SPI using fbtft staging driver.
4335 Load: dtoverlay=ssd1331-spi,<param>=<val>
4336 Params: speed SPI bus speed (default 4500000)
4337 rotate Display rotation (0, 90, 180 or 270; default 0)
4338 fps Delay between frame updates (default 25)
4339 debug Debug output level (0-7; default 0)
4340 dc_pin GPIO pin for D/C (default 24)
4341 reset_pin GPIO pin for RESET (default 25)
4345 Info: Overlay for SSD1351 OLED via SPI using fbtft staging driver.
4346 Load: dtoverlay=ssd1351-spi,<param>=<val>
4347 Params: speed SPI bus speed (default 4500000)
4348 rotate Display rotation (0, 90, 180 or 270; default 0)
4349 fps Delay between frame updates (default 25)
4350 debug Debug output level (0-7; default 0)
4351 dc_pin GPIO pin for D/C (default 24)
4352 reset_pin GPIO pin for RESET (default 25)
4355 Name: superaudioboard
4356 Info: Configures the SuperAudioBoard sound card
4357 Load: dtoverlay=superaudioboard,<param>=<val>
4358 Params: gpiopin GPIO pin for codec reset
4362 Info: Configures the Semtech SX150X I2C GPIO expanders.
4363 Load: dtoverlay=sx150x,<param>=<val>
4364 Params: sx150<x>-<n>-<m> Enables SX150X device on I2C#<n> with slave
4365 address <m>. <x> may be 1-9. <n> may be 0 or 1.
4366 Permissible values of <m> (which is denoted in
4367 hex) depend on the device variant. For SX1501,
4368 SX1502, SX1504 and SX1505, <m> may be 20 or 21.
4369 For SX1503 and SX1506, <m> may be 20. For
4370 SX1507 and SX1509, <m> may be 3E, 3F, 70 or 71.
4371 For SX1508, <m> may be 20, 21, 22 or 23.
4373 sx150<x>-<n>-<m>-int-gpio
4374 Integer, enables interrupts on SX150X device on
4375 I2C#<n> with slave address <m>, specifies
4376 the GPIO pin to which NINT output of SX150X is
4381 Info: Toshiba TC358743 HDMI to CSI-2 bridge chip.
4382 Uses Unicam 1, which is the standard camera connector on most Pi
4384 Load: dtoverlay=tc358743,<param>=<val>
4385 Params: 4lane Use 4 lanes (only applicable to Compute Modules
4388 link-frequency Set the link frequency. Only values of 297000000
4389 (574Mbit/s) and 486000000 (972Mbit/s - default)
4390 are supported by the driver.
4391 media-controller Configure use of Media Controller API for
4392 configuring the sensor (default off)
4393 cam0 Adopt the default configuration for CAM0 on a
4394 Compute Module (CSI0, i2c_vc, and cam0_reg).
4397 Name: tc358743-audio
4398 Info: Used in combination with the tc358743-fast overlay to route the audio
4399 from the TC358743 over I2S to the Pi.
4400 Wiring is LRCK/WFS to GPIO 19, BCK/SCK to GPIO 18, and DATA/SD to GPIO
4402 Load: dtoverlay=tc358743-audio,<param>=<val>
4403 Params: card-name Override the default, "tc358743", card name.
4407 Info: 3.5" Color TFT Display by www.tinylcd.com
4408 Options: Touch, RTC, keypad
4409 Load: dtoverlay=tinylcd35,<param>=<val>
4410 Params: speed Display SPI bus speed
4412 rotate Display rotation {0,90,180,270}
4414 fps Delay between frame updates
4416 debug Debug output level {0-7}
4418 touch Enable touch panel
4420 touchgpio Touch controller IRQ GPIO
4422 xohms Touchpanel: Resistance of X-plate in ohms
4424 rtc-pcf PCF8563 Real Time Clock
4426 rtc-ds DS1307 Real Time Clock
4428 keypad Enable keypad
4431 Display with touchpanel, PCF8563 RTC and keypad:
4432 dtoverlay=tinylcd35,touch,rtc-pcf,keypad
4434 dtoverlay=tinylcd35,touch,touchgpio=3
4438 Info: Enables support for Infineon SLB9670 Trusted Platform Module add-on
4439 boards, which can be used as a secure key storage and hwrng,
4440 available as "Iridium SLB9670" by Infineon and "LetsTrust TPM" by pi3g.
4441 Load: dtoverlay=tpm-slb9670
4446 Info: Enables support for Infineon SLB9673 Trusted Platform Module add-on
4447 boards, which can be used as a secure key storage and hwrng
4448 via the I2C protocol.
4449 Load: dtoverlay=tpm-slb9673
4454 Info: Change the pin usage of uart0
4455 Load: dtoverlay=uart0,<param>=<val>
4456 Params: txd0_pin GPIO pin for TXD0 (14, 32 or 36 - default 14)
4458 rxd0_pin GPIO pin for RXD0 (15, 33 or 37 - default 15)
4460 pin_func Alternative pin function - 4(Alt0) for 14&15,
4461 7(Alt3) for 32&33, 6(Alt2) for 36&37
4465 Info: Enable uart 0 on GPIOs 14-15. Pi 5 only.
4466 Load: dtoverlay=uart0-pi5,<param>
4467 Params: ctsrts Enable CTS/RTS on GPIOs 16-17 (default off)
4471 Info: Change the pin usage of uart1
4472 Load: dtoverlay=uart1,<param>=<val>
4473 Params: txd1_pin GPIO pin for TXD1 (14, 32 or 40 - default 14)
4475 rxd1_pin GPIO pin for RXD1 (15, 33 or 41 - default 15)
4479 Info: Enable uart 1 on GPIOs 0-1. Pi 5 only.
4480 Load: dtoverlay=uart1-pi5,<param>
4481 Params: ctsrts Enable CTS/RTS on GPIOs 2-3 (default off)
4485 Info: Enable uart 2 on GPIOs 0-3. BCM2711 only.
4486 Load: dtoverlay=uart2,<param>
4487 Params: ctsrts Enable CTS/RTS on GPIOs 2-3 (default off)
4491 Info: Enable uart 2 on GPIOs 4-5. Pi 5 only.
4492 Load: dtoverlay=uart2-pi5,<param>
4493 Params: ctsrts Enable CTS/RTS on GPIOs 6-7 (default off)
4497 Info: Enable uart 3 on GPIOs 4-7. BCM2711 only.
4498 Load: dtoverlay=uart3,<param>
4499 Params: ctsrts Enable CTS/RTS on GPIOs 6-7 (default off)
4503 Info: Enable uart 3 on GPIOs 8-9. Pi 5 only.
4504 Load: dtoverlay=uart3-pi5,<param>
4505 Params: ctsrts Enable CTS/RTS on GPIOs 10-11 (default off)
4509 Info: Enable uart 4 on GPIOs 8-11. BCM2711 only.
4510 Load: dtoverlay=uart4,<param>
4511 Params: ctsrts Enable CTS/RTS on GPIOs 10-11 (default off)
4515 Info: Enable uart 4 on GPIOs 12-13. Pi 5 only.
4516 Load: dtoverlay=uart4-pi5,<param>
4517 Params: ctsrts Enable CTS/RTS on GPIOs 14-15 (default off)
4521 Info: Enable uart 5 on GPIOs 12-15. BCM2711 only.
4522 Load: dtoverlay=uart5,<param>
4523 Params: ctsrts Enable CTS/RTS on GPIOs 14-15 (default off)
4527 Info: Configures the NW Digital Radio UDRC Hat
4528 Load: dtoverlay=udrc,<param>=<val>
4529 Params: alsaname Name of the ALSA audio device (default "udrc")
4532 Name: ugreen-dabboard
4533 Info: Configures the ugreen-dabboard I2S overlay
4534 This is a simple overlay based on the simple-audio-card and the dmic
4535 codec. It has the speciality that it is configured to use the codec
4536 as a master I2S device. It works for example with the Si468x DAB
4537 receiver on the uGreen DABBoard.
4538 Load: dtoverlay=ugreen-dabboard,<param>=<val>
4539 Params: card-name Override the default, "dabboard", card name.
4543 Info: Allow usage of downstream .dtb with upstream kernel. Comprises the
4544 vc4-kms-v3d and dwc2 overlays.
4545 Load: dtoverlay=upstream
4549 Name: upstream-aux-interrupt
4550 Info: This overlay has been deprecated and removed because it is no longer
4556 Info: Allow usage of downstream .dtb with upstream kernel on Pi 4. Comprises
4557 the vc4-kms-v3d-pi4 and dwc2 overlays.
4558 Load: dtoverlay=upstream-pi4
4563 Info: Enable Eric Anholt's DRM VC4 V3D driver on top of the dispmanx
4565 Load: dtoverlay=vc4-fkms-v3d,<param>
4566 Params: cma-512 CMA is 512MB (needs 1GB)
4567 cma-448 CMA is 448MB (needs 1GB)
4568 cma-384 CMA is 384MB (needs 1GB)
4569 cma-320 CMA is 320MB (needs 1GB)
4570 cma-256 CMA is 256MB (needs 1GB)
4571 cma-192 CMA is 192MB (needs 1GB)
4572 cma-128 CMA is 128MB
4575 cma-size CMA size in bytes, 4MB aligned
4576 cma-default Use upstream's default value
4579 Name: vc4-fkms-v3d-pi4
4580 Info: Enable Eric Anholt's DRM VC4 V3D driver on top of the dispmanx
4582 Load: dtoverlay=vc4-fkms-v3d-pi4,<param>
4583 Params: cma-512 CMA is 512MB (needs 1GB)
4584 cma-448 CMA is 448MB (needs 1GB)
4585 cma-384 CMA is 384MB (needs 1GB)
4586 cma-320 CMA is 320MB (needs 1GB)
4587 cma-256 CMA is 256MB (needs 1GB)
4588 cma-192 CMA is 192MB (needs 1GB)
4589 cma-128 CMA is 128MB
4592 cma-size CMA size in bytes, 4MB aligned
4593 cma-default Use upstream's default value
4596 Name: vc4-kms-dpi-at056tn53v1
4597 Info: This overlay is now deprecated - see vc4-kms-dpi-panel,at056tn53v1
4601 Name: vc4-kms-dpi-generic
4602 Info: Enable a generic DPI display under KMS. Default timings are for the
4603 Adafruit Kippah with 800x480 panel and RGB666 (GPIOs 0-21)
4604 Requires vc4-kms-v3d to be loaded.
4605 Load: dtoverlay=vc4-kms-dpi-generic,<param>=<val>
4606 Params: clock-frequency Display clock frequency (Hz)
4607 hactive Horizontal active pixels
4608 hfp Horizontal front porch
4609 hsync Horizontal sync pulse width
4610 hbp Horizontal back porch
4611 vactive Vertical active lines
4612 vfp Vertical front porch
4613 vsync Vertical sync pulse width
4614 vbp Vertical back porch
4615 hsync-invert Horizontal sync active low
4616 vsync-invert Vertical sync active low
4617 de-invert Data Enable active low
4618 pixclk-invert Negative edge pixel clock
4619 width-mm Define the screen width in mm
4620 height-mm Define the screen height in mm
4621 rgb565 Change to RGB565 output on GPIOs 0-19
4622 rgb565-padhi Change to RGB565 output on GPIOs 0-8, 12-17, and
4624 bgr666 Change to BGR666 output on GPIOs 0-21.
4625 bgr666-padhi Change to BGR666 output on GPIOs 0-9, 12-17, and
4627 rgb666-padhi Change to RGB666 output on GPIOs 0-9, 12-17, and
4629 bgr888 Change to BGR888 output on GPIOs 0-27
4630 rgb888 Change to RGB888 output on GPIOs 0-27
4631 bus-format Override the bus format for a MEDIA_BUS_FMT_*
4632 value. NB also overridden by rgbXXX overrides.
4633 backlight-gpio Defines a GPIO to be used for backlight control
4635 backlight-pwm Defines a PWM channel to be used for backlight
4636 control (default of none). NB Disables audio
4637 headphone output as that also uses PWM.
4638 backlight-pwm-chan Choose channel on &pwm node for backlight
4641 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
4642 pwm-2chan for valid options.
4643 (default 18 - note this can only work with
4645 backlight-pwm-func Pin function of GPIO used for the PWM
4647 See pwm-2chan for valid options.
4649 backlight-def-brightness
4650 Set the default brightness. Normal range 1-16.
4652 rotate Display rotation {0,90,180,270} (default 0)
4655 Name: vc4-kms-dpi-hyperpixel2r
4656 Info: Enable the KMS drivers for the Pimoroni HyperPixel2 Round DPI display.
4657 Requires vc4-kms-v3d to be loaded.
4658 Load: dtoverlay=vc4-kms-dpi-hyperpixel2r,<param>=<val>
4659 Params: disable-touch Disables the touch controller
4660 touchscreen-inverted-x Inverts X direction of touch controller
4661 touchscreen-inverted-y Inverts Y direction of touch controller
4662 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4663 rotate Display rotation {0,90,180,270} (default 0)
4666 Name: vc4-kms-dpi-hyperpixel4
4667 Info: Enable the KMS drivers for the Pimoroni HyperPixel4 DPI display.
4668 Requires vc4-kms-v3d to be loaded.
4669 Load: dtoverlay=vc4-kms-dpi-hyperpixel4,<param>=<val>
4670 Params: disable-touch Disables the touch controller
4671 touchscreen-inverted-x Inverts X direction of touch controller
4672 touchscreen-inverted-y Inverts Y direction of touch controller
4673 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4674 rotate Display rotation {0,90,180,270} (default 0)
4677 Name: vc4-kms-dpi-hyperpixel4sq
4678 Info: Enable the KMS drivers for the Pimoroni HyperPixel4 Square DPI display.
4679 Requires vc4-kms-v3d to be loaded.
4680 Load: dtoverlay=vc4-kms-dpi-hyperpixel4sq,<param>=<val>
4681 Params: disable-touch Disables the touch controller
4682 touchscreen-inverted-x Inverts X direction of touch controller
4683 touchscreen-inverted-y Inverts Y direction of touch controller
4684 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4685 rotate Display rotation {0,90,180,270} (default 0)
4688 Name: vc4-kms-dpi-panel
4689 Info: Enable a preconfigured KMS DPI panel.
4690 Requires vc4-kms-v3d to be loaded.
4691 Load: dtoverlay=vc4-kms-dpi-panel,<param>=<val>
4692 Params: at056tn53v1 Enable an Innolux 5.6in VGA TFT
4693 kippah-7inch Enable an Adafruit Kippah with 7inch panel.
4694 mzp280 Enable a Geekworm MZP280 panel.
4695 backlight-gpio Defines a GPIO to be used for backlight control
4697 backlight-pwm Defines a PWM channel to be used for backlight
4698 control (default of none). NB Disables audio
4699 headphone output as that also uses PWM.
4700 backlight-pwm-chan Choose channel on &pwm node for backlight
4703 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
4704 pwm-2chan for valid options.
4705 (default 18 - note this can only work with
4707 backlight-pwm-func Pin function of GPIO used for the PWM
4709 See pwm-2chan for valid options.
4711 backlight-def-brightness
4712 Set the default brightness. Normal range 1-16.
4714 rotate Display rotation {0,90,180,270} (default 0)
4717 Name: vc4-kms-dsi-7inch
4718 Info: Enable the Raspberry Pi DSI 7" screen.
4719 Includes the edt-ft5406 for the touchscreen element.
4720 Requires vc4-kms-v3d to be loaded.
4721 Load: dtoverlay=vc4-kms-dsi-7inch,<param>=<val>
4722 Params: sizex Touchscreen size x (default 800)
4723 sizey Touchscreen size y (default 480)
4724 invx Touchscreen inverted x axis
4725 invy Touchscreen inverted y axis
4726 swapxy Touchscreen swapped x y axis
4727 disable_touch Disables the touch screen overlay driver
4728 dsi0 Use DSI0 and i2c_csi_dsi0 (rather than
4729 the default DSI1 and i2c_csi_dsi).
4732 Name: vc4-kms-dsi-lt070me05000
4733 Info: Enable a JDI LT070ME05000 DSI display on DSI1.
4734 Note that this is a 4 lane DSI device, so it will only work on a Compute
4736 Requires vc4-kms-v3d to be loaded.
4737 Load: dtoverlay=vc4-kms-dsi-lt070me05000,<param>
4738 Params: reset GPIO for the reset signal (default 17)
4739 enable GPIO for the enable signal (default 4)
4740 dcdc-en GPIO for the DC-DC converter enable (default 5)
4743 Name: vc4-kms-dsi-lt070me05000-v2
4744 Info: Enable a JDI LT070ME05000 DSI display on DSI1 using Harlab's V2
4746 Note that this is a 4 lane DSI device, so it will only work on a Compute
4748 Requires vc4-kms-v3d to be loaded.
4749 Load: dtoverlay=vc4-kms-dsi-lt070me05000-v2
4753 Name: vc4-kms-dsi-waveshare-panel
4754 Info: Enable a Waveshare DSI touchscreen
4755 Includes the Goodix driver for the touchscreen element.
4756 The default is for the display to be using the I2C0 option for control.
4757 Use the i2c1 override if using the I2C1 wiring with jumper wires from
4758 GPIOs 2&3 (pins 3&5).
4759 invx/invy/swapxy should be used with caution as the panel specifier will
4760 set the default inversions for that panel. Always use them after the
4761 panel specifier, and be aware that you may need to set them as =0, not
4763 Requires vc4-kms-v3d to be loaded.
4764 Load: dtoverlay=vc4-kms-dsi-waveshare-panel,<param>=<val>
4765 Params: 2_8_inch 2.8" 480x640
4766 3_4_inch 3.4" 800x800 round
4767 4_0_inch 4.0" 480x800
4768 7_0_inchC 7.0" C 1024x600
4769 7_9_inch 7.9" 400x1280
4770 8_0_inch 8.0" 1280x800
4771 10_1_inch 10.1" 1280x800
4772 11_9_inch 11.9" 320x1480
4773 i2c1 Use i2c-1 with jumper wires from GPIOs 2&3
4774 disable_touch Disable the touch controller
4775 rotation Set the panel orientation property
4776 invx Touchscreen inverted x axis
4777 invy Touchscreen inverted y axis
4778 swapxy Touchscreen swapped x y axis
4779 dsi0 Use DSI0 and i2c_csi_dsi0 (rather than
4780 the default DSI1 and i2c_csi_dsi).
4783 Name: vc4-kms-kippah-7inch
4784 Info: This overlay is now deprecated - see vc4-kms-dpi-panel,kippah-7inch
4789 Info: Enable Eric Anholt's DRM VC4 HDMI/HVS/V3D driver.
4790 Load: dtoverlay=vc4-kms-v3d,<param>
4791 Params: cma-512 CMA is 512MB (needs 1GB)
4792 cma-448 CMA is 448MB (needs 1GB)
4793 cma-384 CMA is 384MB (needs 1GB)
4794 cma-320 CMA is 320MB (needs 1GB)
4795 cma-256 CMA is 256MB (needs 1GB)
4796 cma-192 CMA is 192MB (needs 1GB)
4797 cma-128 CMA is 128MB
4800 cma-size CMA size in bytes, 4MB aligned
4801 cma-default Use upstream's default value
4802 audio Enable or disable audio over HDMI (default "on")
4803 noaudio Disable all HDMI audio (default "off")
4804 composite Enable the composite output (default "off")
4805 N.B. Disables all other outputs on a Pi 4.
4806 nohdmi Disable HDMI output
4809 Name: vc4-kms-v3d-pi4
4810 Info: Enable Eric Anholt's DRM VC4 HDMI/HVS/V3D driver for Pi4.
4811 Load: dtoverlay=vc4-kms-v3d-pi4,<param>
4812 Params: cma-512 CMA is 512MB
4813 cma-448 CMA is 448MB
4814 cma-384 CMA is 384MB
4815 cma-320 CMA is 320MB
4816 cma-256 CMA is 256MB
4817 cma-192 CMA is 192MB
4818 cma-128 CMA is 128MB
4821 cma-size CMA size in bytes, 4MB aligned
4822 cma-default Use upstream's default value
4823 audio Enable or disable audio over HDMI0 (default
4825 audio1 Enable or disable audio over HDMI1 (default
4827 noaudio Disable all HDMI audio (default "off")
4828 composite Enable the composite output (disables all other
4830 nohdmi Disable both HDMI 0 & 1 outputs
4831 nohdmi0 Disable HDMI 0 output
4832 nohdmi1 Disable HDMI 1 output
4835 Name: vc4-kms-v3d-pi5
4836 Info: See vc4-kms-v3d-pi4 (this is the Pi 5 version)
4839 Name: vc4-kms-vga666
4840 Info: Enable the VGA666 (resistor ladder ADC) for the vc4-kms-v3d driver.
4841 Requires vc4-kms-v3d to be loaded.
4842 Load: dtoverlay=vc4-kms-vga666,<param>
4843 Params: ddc Enables GPIOs 0&1 as the I2C to read the EDID
4844 from the display. NB These are NOT 5V tolerant
4845 GPIOs, therefore level shifters are required.
4849 Info: Overlay for the Fen Logic VGA666 board
4850 This uses GPIOs 2-21 (so no I2C), and activates the output 2-3 seconds
4851 after the kernel has started.
4852 NOT for use with vc4-kms-v3d.
4853 Load: dtoverlay=vga666
4858 Info: Overlay to enable a VIA VL805 USB3 controller on CM4 carriers
4859 Will be loaded automatically by up-to-date firmware if "VL805=1" is
4860 set in the EEPROM config.
4861 Load: dtoverlay=vl805
4866 Info: Configures the w1-gpio Onewire interface module.
4867 Use this overlay if you *don't* need a GPIO to drive an external pullup.
4868 Load: dtoverlay=w1-gpio,<param>=<val>
4869 Params: gpiopin GPIO for I/O (default "4")
4870 pullup Now enabled by default (ignored)
4873 Name: w1-gpio-pullup
4874 Info: Configures the w1-gpio Onewire interface module.
4875 Use this overlay if you *do* need a GPIO to drive an external pullup.
4876 Load: dtoverlay=w1-gpio-pullup,<param>=<val>
4877 Params: gpiopin GPIO for I/O (default "4")
4878 extpullup GPIO for external pullup (default "5")
4879 pullup Now enabled by default (ignored)
4883 Info: Overlay for the Wiznet W5500 Ethernet Controller on SPI0
4884 Load: dtoverlay=w5500,<param>=<val>
4885 Params: int_pin GPIO used for INT (default 25)
4887 speed SPI bus speed (default 30000000)
4889 cs SPI bus Chip Select (default 0)
4892 Name: watterott-display
4893 Info: Watterott RPi-Display - 2.8" Touch Display
4894 Linux has 2 drivers that support this display and this overlay supports
4898 fbtft/fb_ili9341: dtoverlay=watterott-display
4899 drm/mi0283qt: dtoverlay=watterott-display,drm,backlight-pwm,rotate=180
4901 Some notable differences with the DRM driver compared to fbtft:
4902 - The display is turned on when it's first used and not on driver load
4903 as with fbtft. So if nothing uses the display it stays off.
4904 - Can run with a higher SPI clock increasing framerate. This is possible
4905 since the driver avoids messing up the controller configuration due to
4906 transmission errors by running config commands at 10MHz and only pixel
4907 data at full speed (occasional pixel glitch might occur).
4908 - PWM backlight is supported.
4910 Load: dtoverlay=watterott-display,<param>=<val>
4911 Params: speed Display SPI bus speed
4912 rotate Display rotation {0,90,180,270}
4913 fps Delay between frame updates (fbtft only)
4914 debug Debug output level {0-7} (fbtft only)
4915 xohms Touchpanel sensitivity (X-plate resistance)
4916 swapxy Swap x and y axis
4917 backlight Change backlight GPIO pin {e.g. 12, 18}
4919 drm Use DRM/KMS driver mi0283qt instead of fbtft.
4920 Set the SPI clock to 70MHz.
4921 This has to be the first parameter.
4922 backlight-pwm Use pwm for backlight (drm only). NB: Disables
4923 audio headphone output as that also uses PWM.
4926 Name: waveshare-can-fd-hat-mode-a
4927 Info: Overlay for the Waveshare 2-Channel Isolated CAN FD Expansion HAT
4928 for Raspberry Pi, Multi Protections. Use this overlay when the
4929 HAT is configured in Mode A (Default), with can0 on spi0.0
4931 https://www.waveshare.com/2-ch-can-fd-hat.htm
4932 Load: dtoverlay=waveshare-can-fd-hat-mode-a
4936 Name: waveshare-can-fd-hat-mode-b
4937 Info: Overlay for the Waveshare 2-Channel Isolated CAN FD Expansion HAT
4938 for Raspberry Pi, Multi Protections. Use this overlay when the
4939 HAT is configured in Mode B (requires hardware modification), with
4940 can0 on spi0.0 and can1 on spi0.1.
4941 https://www.waveshare.com/2-ch-can-fd-hat.htm
4942 Load: dtoverlay=waveshare-can-fd-hat-mode-b
4947 Info: Configures the wittypi RTC module.
4948 Load: dtoverlay=wittypi,<param>=<val>
4949 Params: led_gpio GPIO for LED (default "17")
4950 led_trigger Choose which activity the LED tracks (default
4954 Name: wm8960-soundcard
4955 Info: Overlay for the Waveshare wm8960 soundcard
4956 Load: dtoverlay=wm8960-soundcard,<param>=<val>
4957 Params: alsaname Changes the card name in ALSA
4958 compatible Changes the codec compatibility
4964 If you are experiencing problems that you think are DT-related, enable DT
4965 diagnostic output by adding this to /boot/config.txt:
4969 and rebooting. Then run:
4973 and look for relevant messages.
4978 This is only meant to be a quick introduction to the subject of Device Tree on
4979 Raspberry Pi. There is a more complete explanation here:
4981 http://www.raspberrypi.org/documentation/configuration/device-tree.md
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