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.
2813 i2c0 Choose the I2C0 bus on GPIOs 0&1
2814 i2c_csi_dsi Choose the I2C0 bus on GPIOs 44&45
2815 i2c3 Choose the I2C3 bus (configure with the i2c3
2816 overlay - BCM2711 only)
2817 i2c4 Choose the I2C4 bus (configure with the i2c4
2818 overlay - BCM2711 only)
2819 i2c5 Choose the I2C5 bus (configure with the i2c5
2820 overlay - BCM2711 only)
2821 i2c6 Choose the I2C6 bus (configure with the i2c6
2822 overlay - BCM2711 only)
2826 Info: Configures the MCP23S08/17 SPI GPIO expanders.
2827 If devices are present on SPI1 or SPI2, those interfaces must be enabled
2828 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2829 If interrupts are enabled for a device on a given CS# on a SPI bus, that
2830 device must be the only one present on that SPI bus/CS#.
2831 Load: dtoverlay=mcp23s17,<param>=<val>
2832 Params: s08-spi<n>-<m>-present 4-bit integer, bitmap indicating MCP23S08
2833 devices present on SPI<n>, CS#<m>
2835 s17-spi<n>-<m>-present 8-bit integer, bitmap indicating MCP23S17
2836 devices present on SPI<n>, CS#<m>
2838 s08-spi<n>-<m>-int-gpio integer, enables interrupts on a single
2839 MCP23S08 device on SPI<n>, CS#<m>, specifies
2840 the GPIO pin to which INT output of MCP23S08
2843 s17-spi<n>-<m>-int-gpio integer, enables mirrored interrupts on a
2844 single MCP23S17 device on SPI<n>, CS#<m>,
2845 specifies the GPIO pin to which either INTA
2846 or INTB output of MCP23S17 is connected.
2850 Info: Configures the MCP2515 CAN controller on spi0/1/2
2851 For devices on spi1 or spi2, the interfaces should be enabled
2852 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2853 Load: dtoverlay=mcp2515,<param>=<val>
2854 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2857 oscillator Clock frequency for the CAN controller (Hz)
2859 speed Maximum SPI frequence (Hz)
2861 interrupt GPIO for interrupt signal
2865 Info: Configures the MCP2515 CAN controller on spi0.0
2866 Load: dtoverlay=mcp2515-can0,<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 MCP2515 CAN controller on spi0.1
2876 Load: dtoverlay=mcp2515-can1,<param>=<val>
2877 Params: oscillator Clock frequency for the CAN controller (Hz)
2879 spimaxfrequency Maximum SPI frequence (Hz)
2881 interrupt GPIO for interrupt signal
2885 Info: Configures the MCP251XFD CAN controller family
2886 For devices on spi1 or spi2, the interfaces should be enabled
2887 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2888 Load: dtoverlay=mcp251xfd,<param>=<val>
2889 Params: spi<n>-<m> Configure device at spi<n>, cs<m>
2892 oscillator Clock frequency for the CAN controller (Hz)
2894 speed Maximum SPI frequence (Hz)
2896 interrupt GPIO for interrupt signal
2898 rx_interrupt GPIO for RX interrupt signal (nINT1) (optional)
2900 xceiver_enable GPIO for CAN transceiver enable (optional)
2902 xceiver_active_high specifiy if CAN transceiver enable pin is
2903 active high (optional, default: active low)
2907 Info: Configures MCP3008 A/D converters
2908 For devices on spi1 or spi2, the interfaces should be enabled
2909 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2910 Load: dtoverlay=mcp3008,<param>[=<val>]
2911 Params: spi<n>-<m>-present boolean, configure device at spi<n>, cs<m>
2912 spi<n>-<m>-speed integer, set the spi bus speed for this device
2916 Info: Configures MCP3202 A/D converters
2917 For devices on spi1 or spi2, the interfaces should be enabled
2918 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
2919 Load: dtoverlay=mcp3202,<param>[=<val>]
2920 Params: spi<n>-<m>-present boolean, configure device at spi<n>, cs<m>
2921 spi<n>-<m>-speed integer, set the spi bus speed for this device
2925 Info: Overlay for activation of Microchip MCP3421-3428 ADCs over I2C
2926 Load: dtoverlay=mcp342x,<param>=<val>
2927 Params: addr I2C bus address of device, for devices with
2928 addresses that are configurable, e.g. by
2929 hardware links (default=0x68)
2930 mcp3421 The device is an MCP3421
2931 mcp3422 The device is an MCP3422
2932 mcp3423 The device is an MCP3423
2933 mcp3424 The device is an MCP3424
2934 mcp3425 The device is an MCP3425
2935 mcp3426 The device is an MCP3426
2936 mcp3427 The device is an MCP3427
2937 mcp3428 The device is an MCP3428
2941 Info: Media Center HAT - 2.83" Touch Display + extras by Pi Supply
2942 Load: dtoverlay=media-center,<param>=<val>
2943 Params: speed Display SPI bus speed
2944 rotate Display rotation {0,90,180,270}
2945 fps Delay between frame updates
2946 xohms Touchpanel sensitivity (X-plate resistance)
2947 swapxy Swap x and y axis
2948 backlight Change backlight GPIO pin {e.g. 12, 18}
2949 debug "on" = enable additional debug messages
2954 Info: Configures the merus-amp audio card
2955 Load: dtoverlay=merus-amp
2960 Info: Configures UART0 (ttyAMA0) so that a requested 38.4kbaud actually gets
2961 31.25kbaud, the frequency required for MIDI
2962 Load: dtoverlay=midi-uart0
2966 Name: midi-uart0-pi5
2967 Info: See midi-uart0 (this is the Pi 5 version)
2971 Info: Configures UART1 (ttyS0) so that a requested 38.4kbaud actually gets
2972 31.25kbaud, the frequency required for MIDI
2973 Load: dtoverlay=midi-uart1
2977 Name: midi-uart1-pi5
2978 Info: See midi-uart1 (this is the Pi 5 version)
2982 Info: Configures UART2 (ttyAMA2) so that a requested 38.4kbaud actually gets
2983 31.25kbaud, the frequency required for MIDI
2984 Load: dtoverlay=midi-uart2
2988 Name: midi-uart2-pi5
2989 Info: See midi-uart2 (this is the Pi 5 version)
2993 Info: Configures UART3 (ttyAMA3) so that a requested 38.4kbaud actually gets
2994 31.25kbaud, the frequency required for MIDI
2995 Load: dtoverlay=midi-uart3
2999 Name: midi-uart3-pi5
3000 Info: See midi-uart3 (this is the Pi 5 version)
3004 Info: Configures UART4 (ttyAMA4) so that a requested 38.4kbaud actually gets
3005 31.25kbaud, the frequency required for MIDI
3006 Load: dtoverlay=midi-uart4
3010 Name: midi-uart4-pi5
3011 Info: See midi-uart4 (this is the Pi 5 version)
3015 Info: Configures UART5 (ttyAMA5) so that a requested 38.4kbaud actually gets
3016 31.25kbaud, the frequency required for MIDI
3017 Load: dtoverlay=midi-uart5
3022 Info: Overlay for AdaFruit Mini Pi 1.3" TFT via SPI using fbtft driver.
3023 Load: dtoverlay=minipitft13,<param>=<val>
3024 Params: speed SPI bus speed (default 32000000)
3025 rotate Display rotation (0, 90, 180 or 270; default 0)
3026 width Display width (default 240)
3027 height Display height (default 240)
3028 fps Delay between frame updates (default 25)
3029 debug Debug output level (0-7; default 0)
3033 Info: Switch the onboard Bluetooth function of a BT-equipped Raspberry Pi
3034 to use the mini-UART (ttyS0) and restore UART0/ttyAMA0 over GPIOs 14 &
3035 15. Note that this option uses a lower baudrate, and should only be used
3036 with low-bandwidth peripherals.
3037 Load: dtoverlay=miniuart-bt,<param>=<val>
3038 Params: krnbt Set to "off" to disable autoprobing of Bluetooth
3039 driver without need of hciattach/btattach
3043 Info: Overlay for SPI-connected MIPI DBI displays using the panel-mipi-dbi
3044 driver. The driver will load a file /lib/firmware/panel.bin containing
3045 the initialisation commands.
3048 dtoverlay=mipi-dbi-spi,spi0-0,speed=70000000
3049 dtparam=width=320,height=240
3050 dtparam=reset-gpio=23,dc-gpio=24
3051 dtparam=backlight-gpio=18
3053 Compared to fbtft panel-mipi-dbi runs pixel data at spi-max-frequency
3054 and init commands at 10MHz. This makes it possible to push the envelope
3055 without messing up the controller configuration due to command
3056 transmission errors.
3058 For devices on spi1 or spi2, the interfaces should be enabled
3059 with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
3061 See https://github.com/notro/panel-mipi-dbi/wiki for more info.
3063 Load: dtoverlay=mipi-dbi-spi,<param>=<val>
3065 compatible Set the compatible string to load a different
3066 firmware file. Both the panel compatible value
3067 used to load the firmware file and the value
3068 used to load the driver has to be set having a
3069 NUL (\0) separator between them.
3071 dtparam=compatible=mypanel\0panel-mipi-dbi-spi
3072 spi<n>-<m> Configure device at spi<n>, cs<m>
3074 speed SPI bus speed in Hz (default 32000000)
3075 cpha Shifted SPI clock phase (CPHA) mode
3076 cpol Inverse SPI clock polarity (CPOL) mode
3077 write-only Controller is not readable
3078 (ie. MISO is not wired up).
3080 width Panel width in pixels (required)
3081 height Panel height in pixels (required)
3082 width-mm Panel width in mm
3083 height-mm Panel height in mm
3084 x-offset Panel x-offset in controller RAM
3085 y-offset Panel y-offset in controller RAM
3087 clock-frequency Panel clock frequency in Hz
3088 (optional, just informational).
3090 reset-gpio GPIO pin to be used for RESET
3091 dc-gpio GPIO pin to be used for D/C
3093 backlight-gpio GPIO pin to be used for backlight control
3095 backlight-pwm PWM channel to be used for backlight control
3096 (default of none). NB Disables audio headphone
3097 output as that also uses PWM.
3098 backlight-pwm-chan Choose channel on &pwm node for backlight
3099 control (default 0).
3100 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
3101 pwm-2chan for valid options (default 18).
3102 backlight-pwm-func Pin function of GPIO used for the PWM backlight.
3103 See pwm-2chan for valid options (default 2).
3104 backlight-def-brightness
3105 Set the default brightness. Normal range 1-16.
3110 Info: Overlay for i2c connected mlx90640 thermal camera
3111 Load: dtoverlay=mlx90640
3116 Info: Selects the bcm2835-mmc SD/MMC driver, optionally with overclock
3117 Load: dtoverlay=mmc,<param>=<val>
3118 Params: overclock_50 Clock (in MHz) to use when the MMC framework
3123 Info: This overlay has been deprecated - use "dtoverlay=i2c-sensor,mpu6050"
3124 instead. Note that "int_pin" is the new name for the "interrupt"
3130 Info: MZ61581 display by Tontec
3131 Load: dtoverlay=mz61581,<param>=<val>
3132 Params: speed Display SPI bus speed
3134 rotate Display rotation {0,90,180,270}
3136 fps Delay between frame updates
3138 txbuflen Transmit buffer length (default 32768)
3140 debug Debug output level {0-7}
3142 xohms Touchpanel sensitivity (X-plate resistance)
3146 Info: Omnivision OV2311 camera module.
3147 Uses Unicam 1, which is the standard camera connector on most Pi
3149 Load: dtoverlay=ov2311,<param>=<val>
3150 Params: rotation Mounting rotation of the camera sensor (0 or
3152 orientation Sensor orientation (0 = front, 1 = rear,
3153 2 = external, default external)
3154 media-controller Configure use of Media Controller API for
3155 configuring the sensor (default on)
3156 cam0 Adopt the default configuration for CAM0 on a
3157 Compute Module (CSI0, i2c_vc, and cam0_reg).
3161 Info: Omnivision OV5647 camera module.
3162 Uses Unicam 1, which is the standard camera connector on most Pi
3164 Load: dtoverlay=ov5647,<param>=<val>
3165 Params: rotation Mounting rotation of the camera sensor (0 or
3167 orientation Sensor orientation (0 = front, 1 = rear,
3168 2 = external, default external)
3169 media-controller Configure use of Media Controller API for
3170 configuring the sensor (default on)
3171 cam0 Adopt the default configuration for CAM0 on a
3172 Compute Module (CSI0, i2c_vc, and cam0_reg).
3173 vcm Configure a VCM focus drive on the sensor.
3177 Info: Omnivision OV7251 camera module.
3178 Uses Unicam 1, which is the standard camera connector on most Pi
3180 Load: dtoverlay=ov7251,<param>=<val>
3181 Params: rotation Mounting rotation of the camera sensor (0 or
3183 orientation Sensor orientation (0 = front, 1 = rear,
3184 2 = external, default external)
3185 media-controller Configure use of Media Controller API for
3186 configuring the sensor (default off)
3187 cam0 Adopt the default configuration for CAM0 on a
3188 Compute Module (CSI0, i2c_vc, and cam0_reg).
3192 Info: Omnivision OV9281 camera module.
3193 Uses Unicam 1, which is the standard camera connector on most Pi
3195 Load: dtoverlay=ov9281,<param>=<val>
3196 Params: rotation Mounting rotation of the camera sensor (0 or
3198 orientation Sensor orientation (0 = front, 1 = rear,
3199 2 = external, default external)
3200 media-controller Configure use of Media Controller API for
3201 configuring the sensor (default on)
3202 cam0 Adopt the default configuration for CAM0 on a
3203 Compute Module (CSI0, i2c_vc, and cam0_reg).
3207 Info: PaPiRus ePaper Screen by Pi Supply (both HAT and pHAT)
3208 Load: dtoverlay=papirus,<param>=<val>
3209 Params: panel Display panel (required):
3214 speed Display SPI bus speed
3218 Info: TI PCA953x family of I2C GPIO expanders. Default is for NXP PCA9534.
3219 Load: dtoverlay=pca953x,<param>=<val>
3220 Params: addr I2C address of expander. Default 0x20.
3221 pca6416 Select the NXP PCA6416 (16 bit)
3222 pca9505 Select the NXP PCA9505 (40 bit)
3223 pca9535 Select the NXP PCA9535 (16 bit)
3224 pca9536 Select the NXP PCA9536 or TI PCA9536 (4 bit)
3225 pca9537 Select the NXP PCA9537 (4 bit)
3226 pca9538 Select the NXP PCA9538 (8 bit)
3227 pca9539 Select the NXP PCA9539 (16 bit)
3228 pca9554 Select the NXP PCA9554 (8 bit)
3229 pca9555 Select the NXP PCA9555 (16 bit)
3230 pca9556 Select the NXP PCA9556 (8 bit)
3231 pca9557 Select the NXP PCA9557 (8 bit)
3232 pca9574 Select the NXP PCA9574 (8 bit)
3233 pca9575 Select the NXP PCA9575 (16 bit)
3234 pca9698 Select the NXP PCA9698 (40 bit)
3235 pcal6416 Select the NXP PCAL6416 (16 bit)
3236 pcal6524 Select the NXP PCAL6524 (24 bit)
3237 pcal9555a Select the NXP PCAL9555A (16 bit)
3238 max7310 Select the Maxim MAX7310 (8 bit)
3239 max7312 Select the Maxim MAX7312 (16 bit)
3240 max7313 Select the Maxim MAX7313 (16 bit)
3241 max7315 Select the Maxim MAX7315 (8 bit)
3242 pca6107 Select the TI PCA6107 (8 bit)
3243 tca6408 Select the TI TCA6408 (8 bit)
3244 tca6416 Select the TI TCA6416 (16 bit)
3245 tca6424 Select the TI TCA6424 (24 bit)
3246 tca9539 Select the TI TCA9539 (16 bit)
3247 tca9554 Select the TI TCA9554 (8 bit)
3248 cat9554 Select the Onnn CAT9554 (8 bit)
3249 pca9654 Select the Onnn PCA9654 (8 bit)
3250 xra1202 Select the Exar XRA1202 (8 bit)
3254 Info: NXP PCF857x family of I2C GPIO expanders.
3255 Load: dtoverlay=pcf857x,<param>=<val>
3256 Params: addr I2C address of expander. Default
3257 depends on model selected.
3258 pcf8574 Select the NXP PCF8574 (8 bit)
3259 pcf8574a Select the NXP PCF8574A (8 bit)
3260 pcf8575 Select the NXP PCF8575 (16 bit)
3261 pca8574 Select the NXP PCA8574 (8 bit)
3264 Name: pcie-32bit-dma
3265 Info: Force PCIe config to support 32bit DMA addresses at the expense of
3266 having to bounce buffers.
3267 Load: dtoverlay=pcie-32bit-dma
3271 [ The pcf2127-rtc overlay has been deleted. See i2c-rtc. ]
3274 [ The pcf8523-rtc overlay has been deleted. See i2c-rtc. ]
3277 [ The pcf8563-rtc overlay has been deleted. See i2c-rtc. ]
3281 Info: This overlay has been renamed act-led, keeping pi3-act-led as an alias
3282 for backwards compatibility.
3286 Name: pi3-disable-bt
3287 Info: This overlay has been renamed disable-bt, keeping pi3-disable-bt as an
3288 alias for backwards compatibility.
3292 Name: pi3-disable-wifi
3293 Info: This overlay has been renamed disable-wifi, keeping pi3-disable-wifi as
3294 an alias for backwards compatibility.
3298 Name: pi3-miniuart-bt
3299 Info: This overlay has been renamed miniuart-bt, keeping pi3-miniuart-bt as
3300 an alias for backwards compatibility.
3305 Info: Configures the pibell audio card.
3306 Load: dtoverlay=pibell,<param>=<val>
3307 Params: alsaname Set the name as it appears in ALSA (default
3312 Info: Configures the PiFace Digital mcp23s17 GPIO port expander.
3313 Load: dtoverlay=pifacedigital,<param>=<val>
3314 Params: spi-present-mask 8-bit integer, bitmap indicating MCP23S17 SPI0
3315 CS0 address. PiFace Digital supports addresses
3316 0-3, which can be configured with JP1 and JP2.
3320 Info: Configures the PiFi 40W stereo amplifier
3321 Load: dtoverlay=pifi-40
3326 Info: Configures the PiFi DAC HD
3327 Load: dtoverlay=pifi-dac-hd
3332 Info: Configures the PiFi DAC Zero
3333 Load: dtoverlay=pifi-dac-zero
3338 Info: Configures the PiFi Mini stereo amplifier
3339 Load: dtoverlay=pifi-mini-210
3344 Info: Configures the PiGlow by pimoroni.com
3345 Load: dtoverlay=piglow
3350 Info: PiScreen display by OzzMaker.com
3351 Load: dtoverlay=piscreen,<param>=<val>
3352 Params: speed Display SPI bus speed
3354 rotate Display rotation {0,90,180,270}
3356 fps Delay between frame updates
3358 debug Debug output level {0-7}
3360 xohms Touchpanel sensitivity (X-plate resistance)
3362 drm Select the DRM/KMS driver instead of the FBTFT
3367 Info: PiScreen 2 with resistive TP display by OzzMaker.com
3368 Load: dtoverlay=piscreen2r,<param>=<val>
3369 Params: speed Display SPI bus speed
3371 rotate Display rotation {0,90,180,270}
3373 fps Delay between frame updates
3375 debug Debug output level {0-7}
3377 xohms Touchpanel sensitivity (X-plate resistance)
3381 Info: Configures the Blokas Labs pisound card
3382 Load: dtoverlay=pisound
3387 Info: Adafruit PiTFT 2.2" screen
3388 Load: dtoverlay=pitft22,<param>=<val>
3389 Params: speed Display SPI bus speed
3391 rotate Display rotation {0,90,180,270}
3393 fps Delay between frame updates
3395 debug Debug output level {0-7}
3398 Name: pitft28-capacitive
3399 Info: Adafruit PiTFT 2.8" capacitive touch screen
3400 Load: dtoverlay=pitft28-capacitive,<param>=<val>
3401 Params: speed Display SPI bus speed
3403 rotate Display rotation {0,90,180,270}
3405 fps Delay between frame updates
3407 debug Debug output level {0-7}
3409 touch-sizex Touchscreen size x (default 240)
3411 touch-sizey Touchscreen size y (default 320)
3413 touch-invx Touchscreen inverted x axis
3415 touch-invy Touchscreen inverted y axis
3417 touch-swapxy Touchscreen swapped x y axis
3420 Name: pitft28-resistive
3421 Info: Adafruit PiTFT 2.8" resistive touch screen
3422 Load: dtoverlay=pitft28-resistive,<param>=<val>
3423 Params: speed Display SPI bus speed
3425 rotate Display rotation {0,90,180,270}
3427 fps Delay between frame updates
3429 debug Debug output level {0-7}
3431 drm Force the use of the mi0283qt DRM driver (by
3432 default the ili9340 framebuffer driver will
3433 be used in preference if available)
3436 Name: pitft35-resistive
3437 Info: Adafruit PiTFT 3.5" resistive touch screen
3438 Load: dtoverlay=pitft35-resistive,<param>=<val>
3439 Params: speed Display SPI bus speed
3441 rotate Display rotation {0,90,180,270}
3443 fps Delay between frame updates
3445 debug Debug output level {0-7}
3447 drm Force the use of the hx8357d DRM driver (by
3448 default the fb_hx8357d framebuffer driver will
3449 be used in preference if available)
3453 Info: Configures the pps-gpio (pulse-per-second time signal via GPIO).
3454 Load: dtoverlay=pps-gpio,<param>=<val>
3455 Params: gpiopin Input GPIO (default "18")
3456 assert_falling_edge When present, assert is indicated by a falling
3457 edge, rather than by a rising edge (default
3459 capture_clear Generate clear events on the trailing edge
3461 pull Desired pull-up/down state (off, down, up)
3466 Info: Configures the PROTO Audio Codec card
3467 Load: dtoverlay=proto-codec
3472 Info: Configures a single PWM channel
3473 Legal pin,function combinations for each channel:
3474 PWM0: 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3475 PWM1: 13,4(Alt0) 19,2(Alt5) 41,4(Alt0) 45,4(Alt0) 53,5(Alt1)
3477 1) Pin 18 is the only one available on all platforms, and
3478 it is the one used by the I2S audio interface.
3479 Pins 12 and 13 might be better choices on an A+, B+ or Pi2.
3480 2) The onboard analogue audio output uses both PWM channels.
3481 3) So be careful mixing audio and PWM.
3482 4) Currently the clock must have been enabled and configured
3484 Load: dtoverlay=pwm,<param>=<val>
3485 Params: pin Output pin (default 18) - see table
3486 func Pin function (default 2 = Alt5) - see above
3487 clock PWM clock frequency (informational)
3491 Info: Configures both PWM channels
3492 Legal pin,function combinations for each channel:
3493 PWM0: 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3494 PWM1: 13,4(Alt0) 19,2(Alt5) 41,4(Alt0) 45,4(Alt0) 53,5(Alt1)
3496 1) Pin 18 is the only one available on all platforms, and
3497 it is the one used by the I2S audio interface.
3498 Pins 12 and 13 might be better choices on an A+, B+ or Pi2.
3499 2) The onboard analogue audio output uses both PWM channels.
3500 3) So be careful mixing audio and PWM.
3501 4) Currently the clock must have been enabled and configured
3503 Load: dtoverlay=pwm-2chan,<param>=<val>
3504 Params: pin Output pin (default 18) - see table
3505 pin2 Output pin for other channel (default 19)
3506 func Pin function (default 2 = Alt5) - see above
3507 func2 Function for pin2 (default 2 = Alt5)
3508 clock PWM clock frequency (informational)
3512 Info: Use GPIO pin as pwm-assisted infrared transmitter output.
3513 This is an alternative to "gpio-ir-tx". pwm-ir-tx makes use
3514 of PWM0 to reduce the CPU load during transmission compared to
3515 gpio-ir-tx which uses bit-banging.
3516 Legal pin,function combinations are:
3517 12,4(Alt0) 18,2(Alt5) 40,4(Alt0) 52,5(Alt1)
3518 Load: dtoverlay=pwm-ir-tx,<param>=<val>
3519 Params: gpio_pin Output GPIO (default 18)
3521 func Pin function (default 2 = Alt5)
3525 Info: Configures one or two PWM channel on PWM1 (BCM2711 only)
3527 1) The onboard analogue audio output uses both PWM channels.
3528 2) So be careful mixing audio and PWM.
3529 Note that even when only one pin is enabled, both channels are available
3530 from the PWM driver, so be careful to use the correct one.
3531 Load: dtoverlay=pwm1,<param>=<val>
3532 Params: clock PWM clock frequency (informational)
3533 pins_40 Enable channel 0 (PWM1_0) on GPIO 40
3534 pins_41 Enable channel 1 (PWM1_1) on GPIO 41
3535 pins_40_41 Enable channels 0 (PWM1_0) and 1 (PW1_1) on
3536 GPIOs 40 and 41 (default)
3537 pull_up Enable pull-ups on the PWM pins (default)
3538 pull_down Enable pull-downs on the PWM pins
3539 pull_off Disable pulls on the PWM pins
3543 Info: in-tech's Evaluation Board for PLC Stamp micro
3544 This uses spi0 and a separate GPIO interrupt to connect the QCA7000.
3545 Load: dtoverlay=qca7000,<param>=<val>
3546 Params: int_pin GPIO pin for interrupt signal (default 23)
3548 speed SPI bus speed (default 12 MHz)
3552 Info: in-tech's Evaluation Board for PLC Stamp micro (UART)
3553 This uses uart0/ttyAMA0 over GPIOs 14 & 15 to connect the QCA7000.
3554 But it requires disabling of onboard Bluetooth on
3555 Pi 3B, 3B+, 3A+, 4B and Zero W.
3556 Load: dtoverlay=qca7000-uart0,<param>=<val>
3557 Params: baudrate Set the baudrate for the UART (default
3562 Info: Enable the preservation of crash logs across a reboot. With
3563 systemd-pstore enabled (as it is on Raspberry Pi OS) the crash logs
3564 are moved to /var/lib/systemd/pstore/ on reboot.
3565 Load: dtoverlay=ramoops,<param>=<val>
3566 Params: base-addr Where to place the capture buffer (default
3568 total-size How much memory to allocate altogether (in
3569 bytes - default 64kB)
3570 record-size How much space to use for each capture, i.e.
3571 total-size / record-size = number of captures
3573 console-size Size of non-panic dmesg captures (default 0)
3577 Info: The version of the ramoops overlay for the Pi 4 family. It should be
3578 loaded automatically if dtoverlay=ramoops is specified on a Pi 4.
3579 Load: dtoverlay=ramoops-pi4,<param>=<val>
3580 Params: base-addr Where to place the capture buffer (default
3582 total-size How much memory to allocate altogether (in
3583 bytes - default 64kB)
3584 record-size How much space to use for each capture, i.e.
3585 total-size / record-size = number of captures
3587 console-size Size of non-panic dmesg captures (default 0)
3590 Name: rotary-encoder
3591 Info: Overlay for GPIO connected rotary encoder.
3592 Load: dtoverlay=rotary-encoder,<param>=<val>
3593 Params: pin_a GPIO connected to rotary encoder channel A
3595 pin_b GPIO connected to rotary encoder channel B
3597 relative_axis register a relative axis rather than an
3598 absolute one. Relative axis will only
3599 generate +1/-1 events on the input device,
3600 hence no steps need to be passed.
3601 linux_axis the input subsystem axis to map to this
3602 rotary encoder. Defaults to 0 (ABS_X / REL_X)
3603 rollover Automatic rollover when the rotary value
3604 becomes greater than the specified steps or
3605 smaller than 0. For absolute axis only.
3606 steps-per-period Number of steps (stable states) per period.
3607 The values have the following meaning:
3608 1: Full-period mode (default)
3610 4: Quarter-period mode
3611 steps Number of steps in a full turnaround of the
3612 encoder. Only relevant for absolute axis.
3613 Defaults to 24 which is a typical value for
3615 wakeup Boolean, rotary encoder can wake up the
3617 encoding String, the method used to encode steps.
3618 Supported are "gray" (the default and more
3619 common) and "binary".
3623 Info: Raspberry Pi official display backlight driver
3624 Load: dtoverlay=rpi-backlight
3628 Name: rpi-cirrus-wm5102
3629 Info: This overlay has been renamed to cirrus-wm5102
3634 Info: Configures the Raspberry Pi Codec Zero sound card
3635 Load: dtoverlay=rpi-codeczero
3640 Info: This overlay has been renamed to i2s-dac.
3645 Info: Configures the Raspberry Pi DAC+ card
3646 Load: dtoverlay=rpi-dacplus,<param>=<val>
3647 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3648 digital volume control. Enable by adding
3649 "dtparam=24db_digital_gain" to config.txt
3650 before any "dtoverlay" lines.
3651 The default behaviour is that the digital
3652 volume control is limited to a maximum of
3653 0dB. ie. it can attenuate but not provide
3654 gain. For most users, this will be desired
3655 as it will prevent clipping. By appending
3656 the 24db_digital_gain parameter, the digital
3657 volume control will allow up to 24dB of
3658 gain. If this parameter is enabled, it is the
3659 responsibility of the user to ensure that
3660 the digital volume control is set to a value
3661 that does not result in clipping/distortion!
3665 Info: Configures the Raspberry Pi DAC Pro sound card
3666 Load: dtoverlay=rpi-dacpro,<param>=<val>
3667 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3668 digital volume control. Enable by adding
3669 "dtparam=24db_digital_gain" to config.txt
3670 before any "dtoverlay" lines.
3671 The default behaviour is that the digital
3672 volume control is limited to a maximum of
3673 0dB. ie. it can attenuate but not provide
3674 gain. For most users, this will be desired
3675 as it will prevent clipping. By appending
3676 the 24db_digital_gain parameter, the digital
3677 volume control will allow up to 24dB of
3678 gain. If this parameter is enabled, it is the
3679 responsibility of the user to ensure that
3680 the digital volume control is set to a value
3681 that does not result in clipping/distortion!
3684 Name: rpi-digiampplus
3685 Info: Configures the Raspberry Pi DigiAMP+ sound card
3686 Load: dtoverlay=rpi-digiampplus,<param>=<val>
3687 Params: 24db_digital_gain Allow gain to be applied via the PCM512x codec
3688 digital volume control. Enable by adding
3689 "dtparam=24db_digital_gain" to config.txt
3690 before any "dtoverlay" lines.
3691 The default behaviour is that the digital
3692 volume control is limited to a maximum of
3693 0dB. ie. it can attenuate but not provide
3694 gain. For most users, this will be desired
3695 as it will prevent clipping. By appending
3696 the 24db_digital_gain parameter, the digital
3697 volume control will allow up to 24dB of
3698 gain. If this parameter is enabled, it is the
3699 responsibility of the user to ensure that
3700 the digital volume control is set to a value
3701 that does not result in clipping/distortion!
3702 auto_mute_amp If specified, unmute/mute the DigiAMP+ when
3703 starting/stopping audio playback (default "on").
3704 unmute_amp If specified, unmute the DigiAMP+ amp once when
3705 the DAC driver module loads (default "off").
3709 Info: This overlay has been renamed to watterott-display
3714 Info: Official Raspberry Pi display touchscreen
3715 Load: dtoverlay=rpi-ft5406,<param>=<val>
3716 Params: touchscreen-size-x Touchscreen X resolution (default 800)
3717 touchscreen-size-y Touchscreen Y resolution (default 600);
3718 touchscreen-inverted-x Invert touchscreen X coordinates (default 0);
3719 touchscreen-inverted-y Invert touchscreen Y coordinates (default 0);
3720 touchscreen-swapped-x-y Swap X and Y cordinates (default 0);
3724 Info: Raspberry Pi PoE HAT fan
3725 Load: dtoverlay=rpi-poe,<param>[=<val>]
3726 Params: poe_fan_temp0 Temperature (in millicelcius) at which the fan
3727 turns on (default 40000)
3728 poe_fan_temp0_hyst Temperature delta (in millicelcius) at which
3729 the fan turns off (default 2000)
3730 poe_fan_temp1 Temperature (in millicelcius) at which the fan
3731 speeds up (default 45000)
3732 poe_fan_temp1_hyst Temperature delta (in millicelcius) at which
3733 the fan slows down (default 2000)
3734 poe_fan_temp2 Temperature (in millicelcius) at which the fan
3735 speeds up (default 50000)
3736 poe_fan_temp2_hyst Temperature delta (in millicelcius) at which
3737 the fan slows down (default 2000)
3738 poe_fan_temp3 Temperature (in millicelcius) at which the fan
3739 speeds up (default 55000)
3740 poe_fan_temp3_hyst Temperature delta (in millicelcius) at which
3741 the fan slows down (default 5000)
3742 i2c Control the fan via Linux I2C drivers instead of
3747 Info: Raspberry Pi PoE+ HAT fan
3748 Load: dtoverlay=rpi-poe-plus,<param>[=<val>]
3749 Params: poe_fan_temp0 Temperature (in millicelcius) at which the fan
3750 turns on (default 40000)
3751 poe_fan_temp0_hyst Temperature delta (in millicelcius) at which
3752 the fan turns off (default 2000)
3753 poe_fan_temp1 Temperature (in millicelcius) at which the fan
3754 speeds up (default 45000)
3755 poe_fan_temp1_hyst Temperature delta (in millicelcius) at which
3756 the fan slows down (default 2000)
3757 poe_fan_temp2 Temperature (in millicelcius) at which the fan
3758 speeds up (default 50000)
3759 poe_fan_temp2_hyst Temperature delta (in millicelcius) at which
3760 the fan slows down (default 2000)
3761 poe_fan_temp3 Temperature (in millicelcius) at which the fan
3762 speeds up (default 55000)
3763 poe_fan_temp3_hyst Temperature delta (in millicelcius) at which
3764 the fan slows down (default 5000)
3765 i2c Control the fan via Linux I2C drivers instead of
3770 Info: This overlay has been renamed to proto-codec.
3775 Info: Raspberry Pi Sense HAT
3776 Load: dtoverlay=rpi-sense
3781 Info: Raspberry Pi Sense HAT v2
3782 Load: dtoverlay=rpi-sense-v2
3787 Info: Raspberry Pi TV HAT
3788 Load: dtoverlay=rpi-tv
3793 Info: This overlay has been deprecated and deleted as the V4L2 stateless
3794 video decoder driver is enabled by default.
3798 Name: rra-digidac1-wm8741-audio
3799 Info: Configures the Red Rocks Audio DigiDAC1 soundcard
3800 Load: dtoverlay=rra-digidac1-wm8741-audio
3805 Info: Overlay for the SPI-connected Sainsmart 1.8" display (based on the
3807 Load: dtoverlay=sainsmart18,<param>=<val>
3808 Params: rotate Display rotation {0,90,180,270}
3809 speed SPI bus speed in Hz (default 4000000)
3810 fps Display frame rate in Hz
3811 bgr Enable BGR mode (default off)
3812 debug Debug output level {0-7}
3813 dc_pin GPIO pin for D/C (default 24)
3814 reset_pin GPIO pin for RESET (default 25)
3818 Info: Overlay for the NXP SC16IS750 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=sc16is750-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)
3828 Info: Overlay for the NXP SC16IS752 dual UART with I2C Interface
3829 Enables the chip on I2C1 at 0x48 (or the "addr" parameter value). To
3830 select another address, please refer to table 10 in reference manual.
3831 Load: dtoverlay=sc16is752-i2c,<param>=<val>
3832 Params: int_pin GPIO used for IRQ (default 24)
3833 addr Address (default 0x48)
3834 xtal On-board crystal frequency (default 14745600)
3837 Name: sc16is752-spi0
3838 Info: Overlay for the NXP SC16IS752 Dual UART with SPI Interface
3839 Enables the chip on SPI0.
3840 Load: dtoverlay=sc16is752-spi0,<param>=<val>
3841 Params: int_pin GPIO used for IRQ (default 24)
3842 xtal On-board crystal frequency (default 14745600)
3845 Name: sc16is752-spi1
3846 Info: Overlay for the NXP SC16IS752 Dual UART with SPI Interface
3847 Enables the chip on SPI1.
3848 N.B.: spi1 is only accessible on devices with a 40pin header, eg:
3849 A+, B+, Zero and PI2 B; as well as the Compute Module.
3851 Load: dtoverlay=sc16is752-spi1,<param>=<val>
3852 Params: int_pin GPIO used for IRQ (default 24)
3853 xtal On-board crystal frequency (default 14745600)
3857 Info: Selects the bcm2835-sdhost SD/MMC driver, optionally with overclock.
3858 N.B. This overlay is designed for situations where the mmc driver is
3859 the default, so it disables the other (mmc) interface - this will kill
3860 WLAN on a Pi3. If this isn't what you want, either use the sdtweak
3861 overlay or the new sd_* dtparams of the base DTBs.
3862 Load: dtoverlay=sdhost,<param>=<val>
3863 Params: overclock_50 Clock (in MHz) to use when the MMC framework
3866 force_pio Disable DMA support (default off)
3868 pio_limit Number of blocks above which to use DMA
3871 debug Enable debug output (default off)
3875 Info: Selects the bcm2835-sdhost SD/MMC driver, optionally with overclock,
3876 and enables SDIO via GPIOs 22-27. An example of use in 1-bit mode is
3877 "dtoverlay=sdio,bus_width=1,gpios_22_25"
3878 Load: dtoverlay=sdio,<param>=<val>
3879 Params: sdio_overclock SDIO Clock (in MHz) to use when the MMC
3880 framework requests 50MHz
3882 poll_once Disable SDIO-device polling every second
3883 (default on: polling once at boot-time)
3885 bus_width Set the SDIO host bus width (default 4 bits)
3887 gpios_22_25 Select GPIOs 22-25 for 1-bit mode. Must be used
3888 with bus_width=1. This replaces the sdio-1bit
3889 overlay, which is now deprecated.
3891 gpios_34_37 Select GPIOs 34-37 for 1-bit mode. Must be used
3894 gpios_34_39 Select GPIOs 34-39 for 4-bit mode. Must be used
3895 with bus_width=4 (the default).
3899 Info: This overlay is now deprecated. Use
3900 "dtoverlay=sdio,bus_width=1,gpios_22_25" instead.
3905 Info: This overlay is now deprecated. Use the sd_* dtparams in the
3906 base DTB, e.g. "dtoverlay=sdtweak,poll_once" becomes
3907 "dtparam=sd_poll_once".
3911 Name: seeed-can-fd-hat-v1
3912 Info: Overlay for Seeed Studio CAN BUS FD HAT with two CAN FD
3913 channels without RTC. Use this overlay if your HAT has no
3915 https://www.seeedstudio.com/2-Channel-CAN-BUS-FD-Shield-for-Raspberry-Pi-p-4072.html
3916 Load: dtoverlay=seeed-can-fd-hat-v1
3920 Name: seeed-can-fd-hat-v2
3921 Info: Overlay for Seeed Studio CAN BUS FD HAT with two CAN FD
3922 channels and an RTC. Use this overlay if your HAT has a
3924 https://www.seeedstudio.com/CAN-BUS-FD-HAT-for-Raspberry-Pi-p-4742.html
3925 Load: dtoverlay=seeed-can-fd-hat-v2
3930 Info: Overlay for SH1106 OLED via SPI using fbtft staging driver.
3931 Load: dtoverlay=sh1106-spi,<param>=<val>
3932 Params: speed SPI bus speed (default 4000000)
3933 rotate Display rotation (0, 90, 180 or 270; default 0)
3934 fps Delay between frame updates (default 25)
3935 debug Debug output level (0-7; default 0)
3936 dc_pin GPIO pin for D/C (default 24)
3937 reset_pin GPIO pin for RESET (default 25)
3938 height Display height (32 or 64; default 64)
3942 Info: Overlay for Si446x UHF Transceiver via SPI using si446x driver.
3943 The driver is currently out-of-tree at
3944 https://github.com/sunipkmukherjee/silabs.git
3945 Load: dtoverlay=si446x-spi0,<param>=<val>
3946 Params: speed SPI bus speed (default 4000000)
3947 int_pin GPIO pin for interrupts (default 17)
3948 reset_pin GPIO pin for RESET (default 27)
3952 Info: Enables the Secondary Memory Interface peripheral. Uses GPIOs 2-25!
3958 Info: Enables the userspace interface for the SMI driver
3959 Load: dtoverlay=smi-dev
3964 Info: Enables access to NAND flash via the SMI interface
3965 Load: dtoverlay=smi-nand
3970 Info: Move SPI function block to GPIO 35 to 39
3971 Load: dtoverlay=spi-gpio35-39
3976 Info: Move SPI function block to GPIOs 40 to 45
3977 Load: dtoverlay=spi-gpio40-45
3982 Info: Adds support for a number of SPI Real Time Clock devices
3983 Load: dtoverlay=spi-rtc,<param>=<val>
3984 Params: ds3232 Select the DS3232 device
3985 ds3234 Select the DS3234 device
3986 pcf2123 Select the PCF2123 device
3988 spi0_0 Use spi0.0 (default)
3994 cs_high This device requires an active-high CS
3998 Info: Don't claim any CS pins for SPI0. Requires a device with its chip
3999 select permanently enabled, but frees a GPIO for e.g. a DPI display.
4000 Load: dtoverlay=spi0-0cs,<param>=<val>
4001 Params: no_miso Don't claim and use the MISO pin (9), freeing
4006 Info: Only use one CS pin for SPI0
4007 Load: dtoverlay=spi0-1cs,<param>=<val>
4008 Params: cs0_pin GPIO pin for CS0 (default 8)
4009 no_miso Don't claim and use the MISO pin (9), freeing
4014 Info: Change the CS pins for SPI0
4015 Load: dtoverlay=spi0-2cs,<param>=<val>
4016 Params: cs0_pin GPIO pin for CS0 (default 8)
4017 cs1_pin GPIO pin for CS1 (default 7)
4018 no_miso Don't claim and use the MISO pin (9), freeing
4023 Info: This overlay has been renamed spi0-2cs, keeping spi0-cs as an
4024 alias for backwards compatibility.
4029 Info: This overlay has been deprecated and removed because it is no longer
4030 necessary and has been seen to prevent spi0 from working.
4035 Info: Enables spi1 with a single chip select (CS) line and associated spidev
4036 dev node. The gpio pin number for the CS line and spidev device node
4037 creation are configurable.
4038 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4039 Load: dtoverlay=spi1-1cs,<param>=<val>
4040 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4041 cs0_spidev Set to 'off' to stop the creation of a
4042 userspace device node /dev/spidev1.0 (default
4043 is 'on' or enabled).
4047 Info: Enables spi1 with two chip select (CS) lines and associated spidev
4048 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4049 creation are configurable.
4050 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4051 Load: dtoverlay=spi1-2cs,<param>=<val>
4052 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4053 cs1_pin GPIO pin for CS1 (default 17 - BCM SPI1_CE1).
4054 cs0_spidev Set to 'off' to stop the creation of a
4055 userspace device node /dev/spidev1.0 (default
4056 is 'on' or enabled).
4057 cs1_spidev Set to 'off' to stop the creation of a
4058 userspace device node /dev/spidev1.1 (default
4059 is 'on' or enabled).
4063 Info: Enables spi1 with three chip select (CS) lines and associated spidev
4064 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4065 creation are configurable.
4066 N.B.: spi1 is not accessible on old Pis without a 40-pin header.
4067 Load: dtoverlay=spi1-3cs,<param>=<val>
4068 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI1_CE0).
4069 cs1_pin GPIO pin for CS1 (default 17 - BCM SPI1_CE1).
4070 cs2_pin GPIO pin for CS2 (default 16 - BCM SPI1_CE2).
4071 cs0_spidev Set to 'off' to stop the creation of a
4072 userspace device node /dev/spidev1.0 (default
4073 is 'on' or enabled).
4074 cs1_spidev Set to 'off' to stop the creation of a
4075 userspace device node /dev/spidev1.1 (default
4076 is 'on' or enabled).
4077 cs2_spidev Set to 'off' to stop the creation of a
4078 userspace device node /dev/spidev1.2 (default
4079 is 'on' or enabled).
4083 Info: Enables spi2 on GPIOs 40-42 with a single chip select (CS) line and
4084 associated spidev dev node. The gpio pin number for the CS line and
4085 spidev device node creation are configurable. spi2-2cs-pi5 is
4086 substituted on a Pi 5.
4087 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4088 Load: dtoverlay=spi2-1cs,<param>=<val>
4089 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4090 cs0_spidev Set to 'off' to stop the creation of a
4091 userspace device node /dev/spidev2.0 (default
4092 is 'on' or enabled).
4096 Info: Enables spi2 on GPIOs 1-3 with a single chip select (CS) line and
4097 associated spidev dev node. The gpio pin number for the CS line and
4098 spidev device node creation are configurable. Pi 5 only.
4099 Load: dtoverlay=spi2-1cs-pi5,<param>=<val>
4100 Params: cs0_pin GPIO pin for CS0 (default 0).
4101 cs0_spidev Set to 'off' to stop the creation of a
4102 userspace device node /dev/spidev2.0 (default
4103 is 'on' or enabled).
4107 Info: Enables spi2 on GPIOs 40-42 with two chip select (CS) lines and
4108 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4109 spidev device node creation are configurable. spi2-2cs-pi5 is
4110 substituted on a Pi 5.
4111 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4112 Load: dtoverlay=spi2-2cs,<param>=<val>
4113 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4114 cs1_pin GPIO pin for CS1 (default 44 - BCM SPI2_CE1).
4115 cs0_spidev Set to 'off' to stop the creation of a
4116 userspace device node /dev/spidev2.0 (default
4117 is 'on' or enabled).
4118 cs1_spidev Set to 'off' to stop the creation of a
4119 userspace device node /dev/spidev2.1 (default
4120 is 'on' or enabled).
4124 Info: Enables spi2 on GPIOs 1-3 with two chip select (CS) lines and
4125 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4126 spidev device node creation are configurable. Pi 5 only.
4127 Load: dtoverlay=spi2-2cs-pi5,<param>=<val>
4128 Params: cs0_pin GPIO pin for CS0 (default 0).
4129 cs1_pin GPIO pin for CS1 (default 24).
4130 cs0_spidev Set to 'off' to stop the creation of a
4131 userspace device node /dev/spidev2.0 (default
4132 is 'on' or enabled).
4133 cs1_spidev Set to 'off' to stop the creation of a
4134 userspace device node /dev/spidev2.1 (default
4135 is 'on' or enabled).
4139 Info: Enables spi2 on GPIOs 40-42 with three chip select (CS) lines and
4140 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4141 spidev device node creation are configurable.
4142 N.B.: spi2 is only accessible with the Compute Module or Pi 5.
4143 Load: dtoverlay=spi2-3cs,<param>=<val>
4144 Params: cs0_pin GPIO pin for CS0 (default 43 - BCM SPI2_CE0).
4145 cs1_pin GPIO pin for CS1 (default 44 - BCM SPI2_CE1).
4146 cs2_pin GPIO pin for CS2 (default 45 - BCM SPI2_CE2).
4147 cs0_spidev Set to 'off' to stop the creation of a
4148 userspace device node /dev/spidev2.0 (default
4149 is 'on' or enabled).
4150 cs1_spidev Set to 'off' to stop the creation of a
4151 userspace device node /dev/spidev2.1 (default
4152 is 'on' or enabled).
4153 cs2_spidev Set to 'off' to stop the creation of a
4154 userspace device node /dev/spidev2.2 (default
4155 is 'on' or enabled).
4159 Info: Enables spi3 on GPIOs 1-3 with a single chip select (CS) line and
4160 associated spidev dev node. The gpio pin number for the CS line and
4161 spidev device node creation are configurable. BCM2711 only,
4162 spi3-1cs-pi5 is substituted on Pi 5.
4163 Load: dtoverlay=spi3-1cs,<param>=<val>
4164 Params: cs0_pin GPIO pin for CS0 (default 0 - BCM SPI3_CE0).
4165 cs0_spidev Set to 'off' to prevent the creation of a
4166 userspace device node /dev/spidev3.0 (default
4167 is 'on' or enabled).
4171 Info: Enables spi3 on GPIOs 5-7 with a single chip select (CS) line and
4172 associated spidev dev node. The gpio pin number for the CS line and
4173 spidev device node creation are configurable. Pi 5 only.
4174 Load: dtoverlay=spi3-1cs-pi5,<param>=<val>
4175 Params: cs0_pin GPIO pin for CS0 (default 4).
4176 cs0_spidev Set to 'off' to prevent the creation of a
4177 userspace device node /dev/spidev3.0 (default
4178 is 'on' or enabled).
4182 Info: Enables spi3 on GPIO2 1-3 with two chip select (CS) lines and
4183 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4184 spidev device node creation are configurable. BCM2711 only,
4185 spi3-2cs-pi5 is substituted on Pi 5.
4186 Load: dtoverlay=spi3-2cs,<param>=<val>
4187 Params: cs0_pin GPIO pin for CS0 (default 0 - BCM SPI3_CE0).
4188 cs1_pin GPIO pin for CS1 (default 24 - BCM SPI3_CE1).
4189 cs0_spidev Set to 'off' to prevent the creation of a
4190 userspace device node /dev/spidev3.0 (default
4191 is 'on' or enabled).
4192 cs1_spidev Set to 'off' to prevent the creation of a
4193 userspace device node /dev/spidev3.1 (default
4194 is 'on' or enabled).
4198 Info: Enables spi3 on GPIOs 5-7 with two chip select (CS) lines and
4199 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4200 spidev device node creation are configurable. Pi 5 only.
4201 Load: dtoverlay=spi3-2cs-pi5,<param>=<val>
4202 Params: cs0_pin GPIO pin for CS0 (default 4).
4203 cs1_pin GPIO pin for CS1 (default 25).
4204 cs0_spidev Set to 'off' to prevent the creation of a
4205 userspace device node /dev/spidev3.0 (default
4206 is 'on' or enabled).
4207 cs1_spidev Set to 'off' to prevent the creation of a
4208 userspace device node /dev/spidev3.1 (default
4209 is 'on' or enabled).
4213 Info: Enables spi4 on GPIOs 5-7 with a single chip select (CS) line and
4214 associated spidev dev node. The gpio pin number for the CS line and
4215 spidev device node creation are configurable. BCM2711 only.
4216 Load: dtoverlay=spi4-1cs,<param>=<val>
4217 Params: cs0_pin GPIO pin for CS0 (default 4 - BCM SPI4_CE0).
4218 cs0_spidev Set to 'off' to prevent the creation of a
4219 userspace device node /dev/spidev4.0 (default
4220 is 'on' or enabled).
4224 Info: Enables spi4 on GPIOs 5-6 with two chip select (CS) lines and
4225 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4226 spidev device node creation are configurable. BCM2711 only.
4227 Load: dtoverlay=spi4-2cs,<param>=<val>
4228 Params: cs0_pin GPIO pin for CS0 (default 4 - BCM SPI4_CE0).
4229 cs1_pin GPIO pin for CS1 (default 25 - BCM SPI4_CE1).
4230 cs0_spidev Set to 'off' to prevent the creation of a
4231 userspace device node /dev/spidev4.0 (default
4232 is 'on' or enabled).
4233 cs1_spidev Set to 'off' to prevent the creation of a
4234 userspace device node /dev/spidev4.1 (default
4235 is 'on' or enabled).
4239 Info: Enables spi5 on GPIOs 13-15 with a single chip select (CS) line and
4240 associated spidev dev node. The gpio pin numbers for the CS lines and
4241 spidev device node creation are configurable. BCM2711 and Pi 5.
4242 Load: dtoverlay=spi5-1cs,<param>=<val>
4243 Params: cs0_pin GPIO pin for CS0 (default 12).
4244 cs0_spidev Set to 'off' to prevent the creation of a
4245 userspace device node /dev/spidev5.0 (default
4246 is 'on' or enabled).
4254 Info: Enables spi5 on GPIOs 13-15 with two chip select (CS) lines and
4255 associated spidev dev nodes. The gpio pin numbers for the CS lines and
4256 spidev device node creation are configurable. BCM2711 and Pi 5.
4257 Load: dtoverlay=spi5-2cs,<param>=<val>
4258 Params: cs0_pin GPIO pin for CS0 (default 12).
4259 cs1_pin GPIO pin for CS1 (default 26).
4260 cs0_spidev Set to 'off' to prevent the creation of a
4261 userspace device node /dev/spidev5.0 (default
4262 is 'on' or enabled).
4263 cs1_spidev Set to 'off' to prevent the creation of a
4264 userspace device node /dev/spidev5.1 (default
4265 is 'on' or enabled).
4273 Info: Enables spi6 with a single chip select (CS) line and associated spidev
4274 dev node. The gpio pin number for the CS line and spidev device node
4275 creation are configurable. BCM2711 only.
4276 Load: dtoverlay=spi6-1cs,<param>=<val>
4277 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI6_CE0).
4278 cs0_spidev Set to 'off' to prevent the creation of a
4279 userspace device node /dev/spidev6.0 (default
4280 is 'on' or enabled).
4284 Info: Enables spi6 with two chip select (CS) lines and associated spidev
4285 dev nodes. The gpio pin numbers for the CS lines and spidev device node
4286 creation are configurable. BCM2711 only.
4287 Load: dtoverlay=spi6-2cs,<param>=<val>
4288 Params: cs0_pin GPIO pin for CS0 (default 18 - BCM SPI6_CE0).
4289 cs1_pin GPIO pin for CS1 (default 27 - BCM SPI6_CE1).
4290 cs0_spidev Set to 'off' to prevent the creation of a
4291 userspace device node /dev/spidev6.0 (default
4292 is 'on' or enabled).
4293 cs1_spidev Set to 'off' to prevent the creation of a
4294 userspace device node /dev/spidev6.1 (default
4295 is 'on' or enabled).
4299 Info: Overlay for activation of SSD1306 over I2C OLED display framebuffer.
4300 Load: dtoverlay=ssd1306,<param>=<val>
4301 Params: address Location in display memory of first character.
4303 width Width of display. (default=128)
4304 height Height of display. (default=64)
4305 offset virtual channel a. (default=0)
4306 normal Has no effect on displays tested. (default=not
4308 sequential Set this if every other scan line is missing.
4310 remapped Set this if display is garbled. (default=not
4312 inverted Set this if display is inverted and mirrored.
4316 Typical usage for 128x64 display: dtoverlay=ssd1306,inverted
4318 Typical usage for 128x32 display: dtoverlay=ssd1306,inverted,sequential
4320 i2c_baudrate=400000 will speed up the display.
4322 i2c_baudrate=1000000 seems to work even though it's not officially
4323 supported by the hardware, and is faster still.
4325 For more information refer to the device datasheet at:
4326 https://cdn-shop.adafruit.com/datasheets/SSD1306.pdf
4330 Info: Overlay for SSD1306 OLED via SPI using fbtft staging driver.
4331 Load: dtoverlay=ssd1306-spi,<param>=<val>
4332 Params: speed SPI bus speed (default 10000000)
4333 rotate Display rotation (0, 90, 180 or 270; default 0)
4334 fps Delay between frame updates (default 25)
4335 debug Debug output level (0-7; default 0)
4336 dc_pin GPIO pin for D/C (default 24)
4337 reset_pin GPIO pin for RESET (default 25)
4338 height Display height (32 or 64; default 64)
4339 inverted Set this if display is inverted and mirrored.
4344 Info: Overlay for SSD1331 OLED via SPI using fbtft staging driver.
4345 Load: dtoverlay=ssd1331-spi,<param>=<val>
4346 Params: speed SPI bus speed (default 4500000)
4347 rotate Display rotation (0, 90, 180 or 270; default 0)
4348 fps Delay between frame updates (default 25)
4349 debug Debug output level (0-7; default 0)
4350 dc_pin GPIO pin for D/C (default 24)
4351 reset_pin GPIO pin for RESET (default 25)
4355 Info: Overlay for SSD1351 OLED via SPI using fbtft staging driver.
4356 Load: dtoverlay=ssd1351-spi,<param>=<val>
4357 Params: speed SPI bus speed (default 4500000)
4358 rotate Display rotation (0, 90, 180 or 270; default 0)
4359 fps Delay between frame updates (default 25)
4360 debug Debug output level (0-7; default 0)
4361 dc_pin GPIO pin for D/C (default 24)
4362 reset_pin GPIO pin for RESET (default 25)
4365 Name: superaudioboard
4366 Info: Configures the SuperAudioBoard sound card
4367 Load: dtoverlay=superaudioboard,<param>=<val>
4368 Params: gpiopin GPIO pin for codec reset
4372 Info: Configures the Semtech SX150X I2C GPIO expanders.
4373 Load: dtoverlay=sx150x,<param>=<val>
4374 Params: sx150<x>-<n>-<m> Enables SX150X device on I2C#<n> with slave
4375 address <m>. <x> may be 1-9. <n> may be 0 or 1.
4376 Permissible values of <m> (which is denoted in
4377 hex) depend on the device variant. For SX1501,
4378 SX1502, SX1504 and SX1505, <m> may be 20 or 21.
4379 For SX1503 and SX1506, <m> may be 20. For
4380 SX1507 and SX1509, <m> may be 3E, 3F, 70 or 71.
4381 For SX1508, <m> may be 20, 21, 22 or 23.
4383 sx150<x>-<n>-<m>-int-gpio
4384 Integer, enables interrupts on SX150X device on
4385 I2C#<n> with slave address <m>, specifies
4386 the GPIO pin to which NINT output of SX150X is
4391 Info: Toshiba TC358743 HDMI to CSI-2 bridge chip.
4392 Uses Unicam 1, which is the standard camera connector on most Pi
4394 Load: dtoverlay=tc358743,<param>=<val>
4395 Params: 4lane Use 4 lanes (only applicable to Compute Modules
4398 link-frequency Set the link frequency. Only values of 297000000
4399 (574Mbit/s) and 486000000 (972Mbit/s - default)
4400 are supported by the driver.
4401 media-controller Configure use of Media Controller API for
4402 configuring the sensor (default off)
4403 cam0 Adopt the default configuration for CAM0 on a
4404 Compute Module (CSI0, i2c_vc, and cam0_reg).
4407 Name: tc358743-audio
4408 Info: Used in combination with the tc358743-fast overlay to route the audio
4409 from the TC358743 over I2S to the Pi.
4410 Wiring is LRCK/WFS to GPIO 19, BCK/SCK to GPIO 18, and DATA/SD to GPIO
4412 Load: dtoverlay=tc358743-audio,<param>=<val>
4413 Params: card-name Override the default, "tc358743", card name.
4417 Info: 3.5" Color TFT Display by www.tinylcd.com
4418 Options: Touch, RTC, keypad
4419 Load: dtoverlay=tinylcd35,<param>=<val>
4420 Params: speed Display SPI bus speed
4422 rotate Display rotation {0,90,180,270}
4424 fps Delay between frame updates
4426 debug Debug output level {0-7}
4428 touch Enable touch panel
4430 touchgpio Touch controller IRQ GPIO
4432 xohms Touchpanel: Resistance of X-plate in ohms
4434 rtc-pcf PCF8563 Real Time Clock
4436 rtc-ds DS1307 Real Time Clock
4438 keypad Enable keypad
4441 Display with touchpanel, PCF8563 RTC and keypad:
4442 dtoverlay=tinylcd35,touch,rtc-pcf,keypad
4444 dtoverlay=tinylcd35,touch,touchgpio=3
4448 Info: Enables support for Infineon SLB9670 Trusted Platform Module add-on
4449 boards, which can be used as a secure key storage and hwrng,
4450 available as "Iridium SLB9670" by Infineon and "LetsTrust TPM" by pi3g.
4451 Load: dtoverlay=tpm-slb9670
4456 Info: Enables support for Infineon SLB9673 Trusted Platform Module add-on
4457 boards, which can be used as a secure key storage and hwrng
4458 via the I2C protocol.
4459 Load: dtoverlay=tpm-slb9673
4464 Info: Change the pin usage of uart0
4465 Load: dtoverlay=uart0,<param>=<val>
4466 Params: txd0_pin GPIO pin for TXD0 (14, 32 or 36 - default 14)
4468 rxd0_pin GPIO pin for RXD0 (15, 33 or 37 - default 15)
4470 pin_func Alternative pin function - 4(Alt0) for 14&15,
4471 7(Alt3) for 32&33, 6(Alt2) for 36&37
4475 Info: Enable uart 0 on GPIOs 14-15. Pi 5 only.
4476 Load: dtoverlay=uart0-pi5,<param>
4477 Params: ctsrts Enable CTS/RTS on GPIOs 16-17 (default off)
4481 Info: Change the pin usage of uart1
4482 Load: dtoverlay=uart1,<param>=<val>
4483 Params: txd1_pin GPIO pin for TXD1 (14, 32 or 40 - default 14)
4485 rxd1_pin GPIO pin for RXD1 (15, 33 or 41 - default 15)
4489 Info: Enable uart 1 on GPIOs 0-1. Pi 5 only.
4490 Load: dtoverlay=uart1-pi5,<param>
4491 Params: ctsrts Enable CTS/RTS on GPIOs 2-3 (default off)
4495 Info: Enable uart 2 on GPIOs 0-3. BCM2711 only.
4496 Load: dtoverlay=uart2,<param>
4497 Params: ctsrts Enable CTS/RTS on GPIOs 2-3 (default off)
4501 Info: Enable uart 2 on GPIOs 4-5. Pi 5 only.
4502 Load: dtoverlay=uart2-pi5,<param>
4503 Params: ctsrts Enable CTS/RTS on GPIOs 6-7 (default off)
4507 Info: Enable uart 3 on GPIOs 4-7. BCM2711 only.
4508 Load: dtoverlay=uart3,<param>
4509 Params: ctsrts Enable CTS/RTS on GPIOs 6-7 (default off)
4513 Info: Enable uart 3 on GPIOs 8-9. Pi 5 only.
4514 Load: dtoverlay=uart3-pi5,<param>
4515 Params: ctsrts Enable CTS/RTS on GPIOs 10-11 (default off)
4519 Info: Enable uart 4 on GPIOs 8-11. BCM2711 only.
4520 Load: dtoverlay=uart4,<param>
4521 Params: ctsrts Enable CTS/RTS on GPIOs 10-11 (default off)
4525 Info: Enable uart 4 on GPIOs 12-13. Pi 5 only.
4526 Load: dtoverlay=uart4-pi5,<param>
4527 Params: ctsrts Enable CTS/RTS on GPIOs 14-15 (default off)
4531 Info: Enable uart 5 on GPIOs 12-15. BCM2711 only.
4532 Load: dtoverlay=uart5,<param>
4533 Params: ctsrts Enable CTS/RTS on GPIOs 14-15 (default off)
4537 Info: Configures the NW Digital Radio UDRC Hat
4538 Load: dtoverlay=udrc,<param>=<val>
4539 Params: alsaname Name of the ALSA audio device (default "udrc")
4542 Name: ugreen-dabboard
4543 Info: Configures the ugreen-dabboard I2S overlay
4544 This is a simple overlay based on the simple-audio-card and the dmic
4545 codec. It has the speciality that it is configured to use the codec
4546 as a master I2S device. It works for example with the Si468x DAB
4547 receiver on the uGreen DABBoard.
4548 Load: dtoverlay=ugreen-dabboard,<param>=<val>
4549 Params: card-name Override the default, "dabboard", card name.
4553 Info: Allow usage of downstream .dtb with upstream kernel. Comprises the
4554 vc4-kms-v3d and dwc2 overlays.
4555 Load: dtoverlay=upstream
4559 Name: upstream-aux-interrupt
4560 Info: This overlay has been deprecated and removed because it is no longer
4566 Info: Allow usage of downstream .dtb with upstream kernel on Pi 4. Comprises
4567 the vc4-kms-v3d-pi4 and dwc2 overlays.
4568 Load: dtoverlay=upstream-pi4
4573 Info: Enable Eric Anholt's DRM VC4 V3D driver on top of the dispmanx
4575 Load: dtoverlay=vc4-fkms-v3d,<param>
4576 Params: cma-512 CMA is 512MB (needs 1GB)
4577 cma-448 CMA is 448MB (needs 1GB)
4578 cma-384 CMA is 384MB (needs 1GB)
4579 cma-320 CMA is 320MB (needs 1GB)
4580 cma-256 CMA is 256MB (needs 1GB)
4581 cma-192 CMA is 192MB (needs 1GB)
4582 cma-128 CMA is 128MB
4585 cma-size CMA size in bytes, 4MB aligned
4586 cma-default Use upstream's default value
4589 Name: vc4-fkms-v3d-pi4
4590 Info: Enable Eric Anholt's DRM VC4 V3D driver on top of the dispmanx
4592 Load: dtoverlay=vc4-fkms-v3d-pi4,<param>
4593 Params: cma-512 CMA is 512MB (needs 1GB)
4594 cma-448 CMA is 448MB (needs 1GB)
4595 cma-384 CMA is 384MB (needs 1GB)
4596 cma-320 CMA is 320MB (needs 1GB)
4597 cma-256 CMA is 256MB (needs 1GB)
4598 cma-192 CMA is 192MB (needs 1GB)
4599 cma-128 CMA is 128MB
4602 cma-size CMA size in bytes, 4MB aligned
4603 cma-default Use upstream's default value
4606 Name: vc4-kms-dpi-at056tn53v1
4607 Info: This overlay is now deprecated - see vc4-kms-dpi-panel,at056tn53v1
4611 Name: vc4-kms-dpi-generic
4612 Info: Enable a generic DPI display under KMS. Default timings are for the
4613 Adafruit Kippah with 800x480 panel and RGB666 (GPIOs 0-21)
4614 Requires vc4-kms-v3d to be loaded.
4615 Load: dtoverlay=vc4-kms-dpi-generic,<param>=<val>
4616 Params: clock-frequency Display clock frequency (Hz)
4617 hactive Horizontal active pixels
4618 hfp Horizontal front porch
4619 hsync Horizontal sync pulse width
4620 hbp Horizontal back porch
4621 vactive Vertical active lines
4622 vfp Vertical front porch
4623 vsync Vertical sync pulse width
4624 vbp Vertical back porch
4625 hsync-invert Horizontal sync active low
4626 vsync-invert Vertical sync active low
4627 de-invert Data Enable active low
4628 pixclk-invert Negative edge pixel clock
4629 width-mm Define the screen width in mm
4630 height-mm Define the screen height in mm
4631 rgb565 Change to RGB565 output on GPIOs 0-19
4632 rgb565-padhi Change to RGB565 output on GPIOs 0-8, 12-17, and
4634 bgr666 Change to BGR666 output on GPIOs 0-21.
4635 bgr666-padhi Change to BGR666 output on GPIOs 0-9, 12-17, and
4637 rgb666-padhi Change to RGB666 output on GPIOs 0-9, 12-17, and
4639 bgr888 Change to BGR888 output on GPIOs 0-27
4640 rgb888 Change to RGB888 output on GPIOs 0-27
4641 bus-format Override the bus format for a MEDIA_BUS_FMT_*
4642 value. NB also overridden by rgbXXX overrides.
4643 backlight-gpio Defines a GPIO to be used for backlight control
4645 backlight-pwm Defines a PWM channel to be used for backlight
4646 control (default of none). NB Disables audio
4647 headphone output as that also uses PWM.
4648 backlight-pwm-chan Choose channel on &pwm node for backlight
4651 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
4652 pwm-2chan for valid options.
4653 (default 18 - note this can only work with
4655 backlight-pwm-func Pin function of GPIO used for the PWM
4657 See pwm-2chan for valid options.
4659 backlight-def-brightness
4660 Set the default brightness. Normal range 1-16.
4662 rotate Display rotation {0,90,180,270} (default 0)
4665 Name: vc4-kms-dpi-hyperpixel2r
4666 Info: Enable the KMS drivers for the Pimoroni HyperPixel2 Round DPI display.
4667 Requires vc4-kms-v3d to be loaded.
4668 Load: dtoverlay=vc4-kms-dpi-hyperpixel2r,<param>=<val>
4669 Params: disable-touch Disables the touch controller
4670 touchscreen-inverted-x Inverts X direction of touch controller
4671 touchscreen-inverted-y Inverts Y direction of touch controller
4672 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4673 rotate Display rotation {0,90,180,270} (default 0)
4676 Name: vc4-kms-dpi-hyperpixel4
4677 Info: Enable the KMS drivers for the Pimoroni HyperPixel4 DPI display.
4678 Requires vc4-kms-v3d to be loaded.
4679 Load: dtoverlay=vc4-kms-dpi-hyperpixel4,<param>=<val>
4680 Params: disable-touch Disables the touch controller
4681 touchscreen-inverted-x Inverts X direction of touch controller
4682 touchscreen-inverted-y Inverts Y direction of touch controller
4683 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4684 rotate Display rotation {0,90,180,270} (default 0)
4687 Name: vc4-kms-dpi-hyperpixel4sq
4688 Info: Enable the KMS drivers for the Pimoroni HyperPixel4 Square DPI display.
4689 Requires vc4-kms-v3d to be loaded.
4690 Load: dtoverlay=vc4-kms-dpi-hyperpixel4sq,<param>=<val>
4691 Params: disable-touch Disables the touch controller
4692 touchscreen-inverted-x Inverts X direction of touch controller
4693 touchscreen-inverted-y Inverts Y direction of touch controller
4694 touchscreen-swapped-x-y Swaps X & Y axes of touch controller
4695 rotate Display rotation {0,90,180,270} (default 0)
4698 Name: vc4-kms-dpi-panel
4699 Info: Enable a preconfigured KMS DPI panel.
4700 Requires vc4-kms-v3d to be loaded.
4701 Load: dtoverlay=vc4-kms-dpi-panel,<param>=<val>
4702 Params: at056tn53v1 Enable an Innolux 5.6in VGA TFT
4703 kippah-7inch Enable an Adafruit Kippah with 7inch panel.
4704 mzp280 Enable a Geekworm MZP280 panel.
4705 backlight-gpio Defines a GPIO to be used for backlight control
4707 backlight-pwm Defines a PWM channel to be used for backlight
4708 control (default of none). NB Disables audio
4709 headphone output as that also uses PWM.
4710 backlight-pwm-chan Choose channel on &pwm node for backlight
4713 backlight-pwm-gpio GPIO pin to be used for the PWM backlight. See
4714 pwm-2chan for valid options.
4715 (default 18 - note this can only work with
4717 backlight-pwm-func Pin function of GPIO used for the PWM
4719 See pwm-2chan for valid options.
4721 backlight-def-brightness
4722 Set the default brightness. Normal range 1-16.
4724 rotate Display rotation {0,90,180,270} (default 0)
4727 Name: vc4-kms-dsi-7inch
4728 Info: Enable the Raspberry Pi DSI 7" screen.
4729 Includes the edt-ft5406 for the touchscreen element.
4730 Requires vc4-kms-v3d to be loaded.
4731 Load: dtoverlay=vc4-kms-dsi-7inch,<param>=<val>
4732 Params: sizex Touchscreen size x (default 800)
4733 sizey Touchscreen size y (default 480)
4734 invx Touchscreen inverted x axis
4735 invy Touchscreen inverted y axis
4736 swapxy Touchscreen swapped x y axis
4737 disable_touch Disables the touch screen overlay driver
4738 dsi0 Use DSI0 and i2c_csi_dsi0 (rather than
4739 the default DSI1 and i2c_csi_dsi).
4742 Name: vc4-kms-dsi-lt070me05000
4743 Info: Enable a JDI LT070ME05000 DSI display on DSI1.
4744 Note that this is a 4 lane DSI device, so it will only work on a Compute
4746 Requires vc4-kms-v3d to be loaded.
4747 Load: dtoverlay=vc4-kms-dsi-lt070me05000,<param>
4748 Params: reset GPIO for the reset signal (default 17)
4749 enable GPIO for the enable signal (default 4)
4750 dcdc-en GPIO for the DC-DC converter enable (default 5)
4753 Name: vc4-kms-dsi-lt070me05000-v2
4754 Info: Enable a JDI LT070ME05000 DSI display on DSI1 using Harlab's V2
4756 Note that this is a 4 lane DSI device, so it will only work on a Compute
4758 Requires vc4-kms-v3d to be loaded.
4759 Load: dtoverlay=vc4-kms-dsi-lt070me05000-v2
4763 Name: vc4-kms-dsi-waveshare-panel
4764 Info: Enable a Waveshare DSI touchscreen
4765 Includes the Goodix driver for the touchscreen element.
4766 The default is for the display to be using the I2C0 option for control.
4767 Use the i2c1 override if using the I2C1 wiring with jumper wires from
4768 GPIOs 2&3 (pins 3&5).
4769 invx/invy/swapxy should be used with caution as the panel specifier will
4770 set the default inversions for that panel. Always use them after the
4771 panel specifier, and be aware that you may need to set them as =0, not
4773 Requires vc4-kms-v3d to be loaded.
4774 Load: dtoverlay=vc4-kms-dsi-waveshare-panel,<param>=<val>
4775 Params: 2_8_inch 2.8" 480x640
4776 3_4_inch 3.4" 800x800 round
4777 4_0_inch 4.0" 480x800
4778 7_0_inchC 7.0" C 1024x600
4779 7_9_inch 7.9" 400x1280
4780 8_0_inch 8.0" 1280x800
4781 10_1_inch 10.1" 1280x800
4782 11_9_inch 11.9" 320x1480
4783 i2c1 Use i2c-1 with jumper wires from GPIOs 2&3
4784 disable_touch Disable the touch controller
4785 rotation Set the panel orientation property
4786 invx Touchscreen inverted x axis
4787 invy Touchscreen inverted y axis
4788 swapxy Touchscreen swapped x y axis
4789 dsi0 Use DSI0 and i2c_csi_dsi0 (rather than
4790 the default DSI1 and i2c_csi_dsi).
4793 Name: vc4-kms-kippah-7inch
4794 Info: This overlay is now deprecated - see vc4-kms-dpi-panel,kippah-7inch
4799 Info: Enable Eric Anholt's DRM VC4 HDMI/HVS/V3D driver.
4800 Load: dtoverlay=vc4-kms-v3d,<param>
4801 Params: cma-512 CMA is 512MB (needs 1GB)
4802 cma-448 CMA is 448MB (needs 1GB)
4803 cma-384 CMA is 384MB (needs 1GB)
4804 cma-320 CMA is 320MB (needs 1GB)
4805 cma-256 CMA is 256MB (needs 1GB)
4806 cma-192 CMA is 192MB (needs 1GB)
4807 cma-128 CMA is 128MB
4810 cma-size CMA size in bytes, 4MB aligned
4811 cma-default Use upstream's default value
4812 audio Enable or disable audio over HDMI (default "on")
4813 noaudio Disable all HDMI audio (default "off")
4814 composite Enable the composite output (default "off")
4815 N.B. Disables all other outputs on a Pi 4.
4816 nohdmi Disable HDMI output
4819 Name: vc4-kms-v3d-pi4
4820 Info: Enable Eric Anholt's DRM VC4 HDMI/HVS/V3D driver for Pi4.
4821 Load: dtoverlay=vc4-kms-v3d-pi4,<param>
4822 Params: cma-512 CMA is 512MB
4823 cma-448 CMA is 448MB
4824 cma-384 CMA is 384MB
4825 cma-320 CMA is 320MB
4826 cma-256 CMA is 256MB
4827 cma-192 CMA is 192MB
4828 cma-128 CMA is 128MB
4831 cma-size CMA size in bytes, 4MB aligned
4832 cma-default Use upstream's default value
4833 audio Enable or disable audio over HDMI0 (default
4835 audio1 Enable or disable audio over HDMI1 (default
4837 noaudio Disable all HDMI audio (default "off")
4838 composite Enable the composite output (disables all other
4840 nohdmi Disable both HDMI 0 & 1 outputs
4841 nohdmi0 Disable HDMI 0 output
4842 nohdmi1 Disable HDMI 1 output
4845 Name: vc4-kms-v3d-pi5
4846 Info: See vc4-kms-v3d-pi4 (this is the Pi 5 version)
4849 Name: vc4-kms-vga666
4850 Info: Enable the VGA666 (resistor ladder ADC) for the vc4-kms-v3d driver.
4851 Requires vc4-kms-v3d to be loaded.
4852 Load: dtoverlay=vc4-kms-vga666,<param>
4853 Params: ddc Enables GPIOs 0&1 as the I2C to read the EDID
4854 from the display. NB These are NOT 5V tolerant
4855 GPIOs, therefore level shifters are required.
4859 Info: Overlay for the Fen Logic VGA666 board
4860 This uses GPIOs 2-21 (so no I2C), and activates the output 2-3 seconds
4861 after the kernel has started.
4862 NOT for use with vc4-kms-v3d.
4863 Load: dtoverlay=vga666
4868 Info: Overlay to enable a VIA VL805 USB3 controller on CM4 carriers
4869 Will be loaded automatically by up-to-date firmware if "VL805=1" is
4870 set in the EEPROM config.
4871 Load: dtoverlay=vl805
4876 Info: Configures the w1-gpio Onewire interface module.
4877 Use this overlay if you *don't* need a GPIO to drive an external pullup.
4878 Load: dtoverlay=w1-gpio,<param>=<val>
4879 Params: gpiopin GPIO for I/O (default "4")
4880 pullup Now enabled by default (ignored)
4883 Name: w1-gpio-pullup
4884 Info: Configures the w1-gpio Onewire interface module.
4885 Use this overlay if you *do* need a GPIO to drive an external pullup.
4886 Load: dtoverlay=w1-gpio-pullup,<param>=<val>
4887 Params: gpiopin GPIO for I/O (default "4")
4888 extpullup GPIO for external pullup (default "5")
4889 pullup Now enabled by default (ignored)
4893 Info: Overlay for the Wiznet W5500 Ethernet Controller on SPI0
4894 Load: dtoverlay=w5500,<param>=<val>
4895 Params: int_pin GPIO used for INT (default 25)
4897 speed SPI bus speed (default 30000000)
4899 cs SPI bus Chip Select (default 0)
4902 Name: watterott-display
4903 Info: Watterott RPi-Display - 2.8" Touch Display
4904 Linux has 2 drivers that support this display and this overlay supports
4908 fbtft/fb_ili9341: dtoverlay=watterott-display
4909 drm/mi0283qt: dtoverlay=watterott-display,drm,backlight-pwm,rotate=180
4911 Some notable differences with the DRM driver compared to fbtft:
4912 - The display is turned on when it's first used and not on driver load
4913 as with fbtft. So if nothing uses the display it stays off.
4914 - Can run with a higher SPI clock increasing framerate. This is possible
4915 since the driver avoids messing up the controller configuration due to
4916 transmission errors by running config commands at 10MHz and only pixel
4917 data at full speed (occasional pixel glitch might occur).
4918 - PWM backlight is supported.
4920 Load: dtoverlay=watterott-display,<param>=<val>
4921 Params: speed Display SPI bus speed
4922 rotate Display rotation {0,90,180,270}
4923 fps Delay between frame updates (fbtft only)
4924 debug Debug output level {0-7} (fbtft only)
4925 xohms Touchpanel sensitivity (X-plate resistance)
4926 swapxy Swap x and y axis
4927 backlight Change backlight GPIO pin {e.g. 12, 18}
4929 drm Use DRM/KMS driver mi0283qt instead of fbtft.
4930 Set the SPI clock to 70MHz.
4931 This has to be the first parameter.
4932 backlight-pwm Use pwm for backlight (drm only). NB: Disables
4933 audio headphone output as that also uses PWM.
4936 Name: waveshare-can-fd-hat-mode-a
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 A (Default), with can0 on spi0.0
4941 https://www.waveshare.com/2-ch-can-fd-hat.htm
4942 Load: dtoverlay=waveshare-can-fd-hat-mode-a
4946 Name: waveshare-can-fd-hat-mode-b
4947 Info: Overlay for the Waveshare 2-Channel Isolated CAN FD Expansion HAT
4948 for Raspberry Pi, Multi Protections. Use this overlay when the
4949 HAT is configured in Mode B (requires hardware modification), with
4950 can0 on spi0.0 and can1 on spi0.1.
4951 https://www.waveshare.com/2-ch-can-fd-hat.htm
4952 Load: dtoverlay=waveshare-can-fd-hat-mode-b
4957 Info: Configures the wittypi RTC module.
4958 Load: dtoverlay=wittypi,<param>=<val>
4959 Params: led_gpio GPIO for LED (default "17")
4960 led_trigger Choose which activity the LED tracks (default
4964 Name: wm8960-soundcard
4965 Info: Overlay for the Waveshare wm8960 soundcard
4966 Load: dtoverlay=wm8960-soundcard,<param>=<val>
4967 Params: alsaname Changes the card name in ALSA
4968 compatible Changes the codec compatibility
4974 If you are experiencing problems that you think are DT-related, enable DT
4975 diagnostic output by adding this to /boot/config.txt:
4979 and rebooting. Then run:
4983 and look for relevant messages.
4988 This is only meant to be a quick introduction to the subject of Device Tree on
4989 Raspberry Pi. There is a more complete explanation here:
4991 http://www.raspberrypi.org/documentation/configuration/device-tree.md