[PATCH] leds: sgm3140: Add missing timer cleanup and flash gpio control

From: Ondřej Jirman
Date: Sat Feb 17 2024 - 14:11:45 EST


From: Ondrej Jirman <megi@xxxxxx>

Enabling strobe and then setting brightness to 0 causes the driver to enter
invalid state after strobe end timer fires. We should cancel strobe mode
resources when changing brightness (aka torch mode).

Fixes: cef8ec8cbd21 ("leds: add sgm3140 driver")
Signed-off-by: Ondrej Jirman <megi@xxxxxx>
---
I also have a sense the driver has other issues, like running regulator_disable
in atomic context, and lacking locking in general. But that's for another time.

I don't think this device is typically used from multiple threads/processes.
But writing strobe = 1 and then brightness = 0 affects real usecases.

drivers/leds/flash/leds-sgm3140.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/leds/flash/leds-sgm3140.c b/drivers/leds/flash/leds-sgm3140.c
index eb648ff54b4e..db0ac6641954 100644
--- a/drivers/leds/flash/leds-sgm3140.c
+++ b/drivers/leds/flash/leds-sgm3140.c
@@ -114,8 +114,11 @@ static int sgm3140_brightness_set(struct led_classdev *led_cdev,
"failed to enable regulator: %d\n", ret);
return ret;
}
+ gpiod_set_value_cansleep(priv->flash_gpio, 0);
gpiod_set_value_cansleep(priv->enable_gpio, 1);
} else {
+ del_timer_sync(&priv->powerdown_timer);
+ gpiod_set_value_cansleep(priv->flash_gpio, 0);
gpiod_set_value_cansleep(priv->enable_gpio, 0);
ret = regulator_disable(priv->vin_regulator);
if (ret) {
--
2.43.0