I have a pi3 model B+
As an exercise, I connected a led to GPIO pin 21 (with series etc) and tried to associate it with the "gpio-leds" driver.
I compiled a small overlay inserting myled and the resulting "leds" part of the device tree now looks like this afterAfter this I was expecting at least to see that gpio pin 21 (hex 0x15) to be allocated.
Instead gpioinfo shows:Why are the device tree changes not applied?
Is there another command I need to issue?
or
What is the correct way to add a new gpio pin/led to the "gpio-leds" driver so I can use one of the triggers?
Thank You
As an exercise, I connected a led to GPIO pin 21 (with series etc) and tried to associate it with the "gpio-leds" driver.
I compiled a small overlay inserting myled and the resulting "leds" part of the device tree now looks like this after
Code:
sudo dtoverlay new-led.dtbo Code:
leds { compatible = "gpio-leds"; phandle = <0x9a>; led-act { linux,default-trigger = "mmc0"; label = "ACT"; default-state = "off"; phandle = <0x3c>; gpios = <0x07 0x1d 0x00>; }; myled { linux,default-trigger = "heartbeat"; label = "Heartbeat"; default-state = "off"; status = "true"; phandle = <0x9c>; gpios = <0x07 0x15 0x00>; }; led-pwr { linux,default-trigger = "default-on"; label = "PWR"; default-state = "off"; phandle = <0x3d>; gpios = <0x0b 0x02 0x01>; }; };Instead gpioinfo shows:
Code:
line 20: "GPIO20" unused input active-high line 21: "GPIO21" unused input active-high -- why is this still unused after the device tree changes?line 22: "GPIO22" unused input active-high Is there another command I need to issue?
or
What is the correct way to add a new gpio pin/led to the "gpio-leds" driver so I can use one of the triggers?
Thank You
Statistics: Posted by bcperth — Fri Apr 04, 2025 5:00 am — Replies 1 — Views 24