I changed the file according to your recommendation. I still get the same error:
=> Adding device-tree overlay 'verdin-imx8mp_backlight_overlay.dts'
Error: verdin-imx8mp_backlight_overlay.dts:7.13-14 syntax error
FATAL ERROR: Unable to parse input tree
error: cannot apply verdin-imx8mp_backlight_overlay.dts.
Hello @mvo,
Sorry about the delay in getting back to you here. It took some time for me to figure this out.
In case it is helpful for anyone else browsing around here, the first thing important is to set the device tree to that for ivy board (# setenv fdtfile imx8mp-verdin-wifi-ivy.dtb) if it is not correctly set - by default, the Torizon OS and BSP images use the device tree file for verdin dev board.
The LEDs should be available and can be controlled through the /sys/class/leds/ interface. You can toggle all LEDs (D9, D5, D8, D7) using this. (By default, D9.Green is always ON and cannot be controlled, D5 is always ON and is Green - you will see why in the schematics of Ivy - section LEDs). This will leave you with the options to toggle the following LEDs:
D9: Red, Blue
D8: Red, Blue, Green
D7: Red, Blue, Green
This is what you will have by default in /sys/class/leds/:
root@verdin-imx8mp-15035975:~# ls /sys/class/leds/
blue:status-1 blue:status-2 blue:status-3 green:status-1 green:status-2 red:status-1 red:status-2 red:status-3
where,
status-1 → D7
status-2 → D8
status-3 → D9
You can toggle any of these available LEDs by writing 1 to the brightness as in:
root@verdin-imx8mp-15035975:/sys/class/leds/blue:status-3# echo 1 > brightness
Testing all these LEDs will give you an indication that these LEDs are configured correctly in the device tree. However, toggling them via GPIO does not work for all of them yet. This is because the pin control for leds is not added into pinctrl-0 for iomuxc yet. So I modified the file imx8mp-verdin-ivy.dtsi to add it. Also, the GPIOs for certain pins (SODIMM 30, 32, 34, 54) were left unnamed in this device tree. I gave it a name and rebuilt the device tree. Here is my diff:
diff --git a/arch/arm64/boot/dts/freescale/imx8mp-verdin-ivy.dtsi b/arch/arm64/boot/dts/freescale/imx8mp-verdin-ivy.dtsi
index db1b4ee7728c..cdbf77f2f049 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp-verdin-ivy.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp-verdin-ivy.dtsi
@@ -328,7 +328,7 @@ &gpio1 {
&gpio3 {
gpio-line-names =
"", /* 0 */
- "",
+ "LED_D8_GREEN", /* SODIMM 54 */
"",
"",
"",
@@ -346,13 +346,13 @@ &gpio3 {
"REL3", /* SODIMM 64 */
"",
"",
- "",
+ "LED_D7_RED", /* SODIMM 34 */
"", /* 20 */
"",
+ "LED_D7_GREEN", /* SODIMM 32 */
"",
"",
- "",
- "",
+ "LED_D7_BLUE", /* SODIMM 30 */
"",
"",
"",
@@ -482,7 +482,7 @@ &iomuxc {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_gpio2>, <&pinctrl_gpio3>,
- <&pinctrl_ivy_dig_inputs>, <&pinctrl_ivy_relays>;
+ <&pinctrl_ivy_dig_inputs>, <&pinctrl_ivy_relays>, <&pinctrl_ivy_leds>;
pinctrl_ivy_dig_inputs: ivydiginputsgrp {
fsl,pins =
Once this device tree is built and applied, you will see all these GPIO pins named and available in gpioinfo. (The truth is, these pins were available earlier but were unnamed, and could also be toggled with the right gpiochip and line numbers, after you add pinctrl_ivy_leds into pinctrl-0). With the above change in the devie tree, you should see those GPIO pins with the new names:
root@verdin-imx8mp-15035975:~# gpioinfo
gpiochip0 - 32 lines:
line 0: unnamed output active-low consumer=spi1 CS1
line 1: "GPIO2" input
line 2: unnamed input
line 3: unnamed input
line 4: unnamed input
line 5: "GPIO3" input
line 6: unnamed output active-low consumer=spi1 CS2
line 7: unnamed output consumer=mux
line 8: unnamed output consumer=mux
line 9: unnamed output
line 10: unnamed input
line 11: unnamed input
line 12: unnamed output consumer=regulator-usb1-vbus
line 13: unnamed input
line 14: unnamed output consumer=regulator-usb2-vbus
line 15: unnamed input
line 16: unnamed input
line 17: unnamed input
line 18: unnamed input
line 19: unnamed input
line 20: unnamed input
line 21: unnamed input
line 22: unnamed input
line 23: unnamed input
line 24: unnamed input
line 25: unnamed input
line 26: unnamed input
line 27: unnamed input
line 28: unnamed input
line 29: unnamed input
line 30: unnamed input
line 31: unnamed input
gpiochip1 - 32 lines:
line 0: unnamed input
line 1: unnamed input
line 2: unnamed input
line 3: unnamed input
line 4: unnamed input
line 5: unnamed input
line 6: "SODIMM_143" input
line 7: "SODIMM_141" input
line 8: unnamed input
line 9: unnamed input
line 10: "SODIMM_161" input consumer="id"
line 11: unnamed output consumer=regulator-wifi-en
line 12: "SODIMM_84" input active-low consumer="cd"
line 13: "SODIMM_78" input
line 14: "SODIMM_74" input
line 15: "SODIMM_80" input
line 16: "SODIMM_82" input
line 17: "SODIMM_70" input
line 18: "SODIMM_72" input
line 19: unnamed input
line 20: unnamed output consumer=regulator-module-eth1phy
line 21: unnamed input
line 22: unnamed input
line 23: unnamed input
line 24: unnamed input
line 25: unnamed input
line 26: unnamed input
line 27: unnamed input
line 28: unnamed input
line 29: unnamed input
line 30: unnamed input
line 31: unnamed input
gpiochip2 - 32 lines:
line 0: unnamed input
line 1: "LED_D8_GREEN" input
line 2: unnamed input
line 3: unnamed input
line 4: unnamed input
line 5: unnamed input
line 6: "DIG_1" input
line 7: "DIG_2" input
line 8: "REL1" input
line 9: "REL2" input
line 10: unnamed input
line 11: unnamed input
line 12: unnamed input
line 13: unnamed input
line 14: "REL4" input
line 15: unnamed input
line 16: "REL3" input
line 17: unnamed input
line 18: unnamed input
line 19: "LED_D7_RED" input
line 20: unnamed input
line 21: unnamed input
line 22: "LED_D7_GREEN" input
line 23: unnamed input
line 24: unnamed input
line 25: "LED_D7_BLUE" input
line 26: unnamed input
line 27: unnamed input
line 28: unnamed input
line 29: unnamed input
line 30: unnamed input
line 31: unnamed input
gpiochip3 - 32 lines:
line 0: "SODIMM_252" input active-low consumer="Wake-Up"
line 1: "SODIMM_222" input
line 2: "SODIMM_36" input
line 3: "SODIMM_220" input
line 4: "SODIMM_193" input
line 5: "SODIMM_191" input
line 6: "SODIMM_201" input
line 7: "SODIMM_203" input
line 8: "SODIMM_205" input
line 9: "SODIMM_207" input
line 10: "SODIMM_199" input
line 11: "SODIMM_197" input
line 12: "SODIMM_221" input
line 13: "SODIMM_219" input
line 14: "SODIMM_217" input
line 15: "SODIMM_215" input
line 16: "SODIMM_211" input
line 17: "SODIMM_213" input
line 18: "SODIMM_189" input
line 19: "SODIMM_244" output consumer="PCIe reset"
line 20: "SODIMM_38" input
line 21: unnamed input
line 22: "SODIMM_76" output consumer="regulator-usdhc2"
line 23: "SODIMM_135" input
line 24: "SODIMM_133" input
line 25: "SODIMM_17" input
line 26: "SODIMM_24" input
line 27: "SODIMM_26" input
line 28: "SODIMM_21" input
line 29: "SODIMM_256" output consumer="regulator-force-sleep-moci"
line 30: "SODIMM_48" input
line 31: "SODIMM_44" input
gpiochip4 - 32 lines:
line 0: "SODIMM_42" input
line 1: "SODIMM_46" input
line 2: "SODIMM_187" input
line 3: "SODIMM_20" input
line 4: "SODIMM_22" input
line 5: "SODIMM_15" input
line 6: "SODIMM_196" input
line 7: "SODIMM_200" input
line 8: "SODIMM_198" input
line 9: "SODIMM_202" output active-low consumer="spi1 CS0"
line 10: unnamed input
line 11: unnamed input
line 12: unnamed input
line 13: unnamed input
line 14: unnamed output drive=open-drain consumer=scl
line 15: unnamed input drive=open-drain consumer=sda
line 16: "SODIMM_55" input
line 17: "SODIMM_53" input
line 18: "SODIMM_95" output drive=open-drain consumer="scl"
line 19: "SODIMM_93" input drive=open-drain consumer="sda"
line 20: "SODIMM_14" output drive=open-drain consumer="scl"
line 21: "SODIMM_12" input drive=open-drain consumer="sda"
line 22: "SODIMM_129" input
line 23: "SODIMM_131" input
line 24: "SODIMM_137" input
line 25: "SODIMM_139" input
line 26: "SODIMM_147" input
line 27: "SODIMM_149" input
line 28: "SODIMM_151" input
line 29: "SODIMM_153" input
line 30: unnamed input
line 31: unnamed input
With this, you can toggle those LEDs with GPIO using the gpioset commands.