[PATCH v2 0/3] Rewrite GPIO LED trigger to use trigger-sources

[Linus Walleij <linus.walleij@linaro.org>]

This rewrites the platform-data GPIO LED trigger to instead
use fwnode trigger-sources to describe the LED used.

This will work out-of-the-box with e.g. device tree.

Tested with real hardware by modifying a device tree adding
trigger-sources to a LED and trigger-source-cells to
a gpio chip, setting the trigger to a pushbutton. It works
like a charm, once the trigger is set to "gpio".

Adding trigger-sources to GPIO chips in a simple way requires
this patch to be merged to the generic dtschema:
https://lore.kernel.org/linux-devicetree/20230916-gpio-triggers-v1-1-6e5052bead9a@linaro.org/

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
Changes in v2:
- Add a quirk to gpiolib-of to allow to read out trigger-sources as
  any regular GPIO.
- Fix a use-after-free bug found by Dan Carpenter.
- Tested on hardware.
- Link to v1: https://lore.kernel.org/r/20230912-gpio-led-trigger-dt-v1-0-1b50e3756dda@linaro.org

---
Linus Walleij (3):
      gpiolib: of: Allow "trigger-sources" to reference a GPIO
      dt-bindings: leds: Mention GPIO triggers
      leds: triggers: gpio: Rewrite to use trigger-sources

 Documentation/devicetree/bindings/leds/common.yaml |   2 +
 drivers/gpio/gpiolib-of.c                          |  28 +++++
 drivers/leds/trigger/Kconfig                       |   5 +-
 drivers/leds/trigger/ledtrig-gpio.c                | 137 ++++++---------------
 4 files changed, 71 insertions(+), 101 deletions(-)
---
base-commit: 8eb1c4d9b44873d30efc1846148944534f4a017d
change-id: 20230911-gpio-led-trigger-dt-922bbe21fa22

Best regards,
-- 
Linus Walleij <linus.walleij@linaro.org>