2024-02-17 19:11:46

by Ondřej Jirman

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

From: Ondrej Jirman <[email protected]>

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 <[email protected]>
---
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



2024-02-23 16:14:34

by Lee Jones

[permalink] [raw]
Subject: Re: (subset) [PATCH] leds: sgm3140: Add missing timer cleanup and flash gpio control

On Sat, 17 Feb 2024 20:11:30 +0100, Ondřej Jirman wrote:
> 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).
>
>

Applied, thanks!

[1/1] leds: sgm3140: Add missing timer cleanup and flash gpio control
commit: 3e7b2b9309cd3eb1b82121b8a978d2dd19301924

--
Lee Jones [李琼斯]