diff options
| author | Cong Nguyen <congnt264@gmail.com> | 2026-09-01 22:54:04 +0700 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2026-09-09 18:16:35 -0700 |
| commit | bb2424c3502cc72292eedade46960c331d5f28fb (patch) | |
| tree | fdb0c65076779c164bb12f9dfffbbabbf8125586 | |
| parent | 508baf1713f32f287bfb4f85d759403ec8ba35a3 (diff) | |
hwmon: (gpio-fan) take fan_data->lock in gpio_fan_shutdown()
set_fan_speed() writes the control GPIOs one bit at a time. Every
other caller locks around it; gpio_fan_shutdown() doesn't. If it races
a locked caller, the GPIO writes can interleave and leave the fan at a
speed neither caller asked for.
Fixes: b95579cd8795 ("hwmon: (gpio-fan) Add a shutdown handler to poweroff the fans")
Reported-by: Sashiko AI review <sashiko-bot@kernel.org>
Link: https://lore.kernel.org/r/20260830152150.27F5F1F000E9@smtp.kernel.org
Assisted-by: Claude:claude-opus-4
Signed-off-by: Cong Nguyen <congnt264@gmail.com>
Link: https://patch.msgid.link/20260901155404.1532092-1-congnt264@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
| -rw-r--r-- | drivers/hwmon/gpio-fan.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c index 7f36e5f6f223..df8bd9707605 100644 --- a/drivers/hwmon/gpio-fan.c +++ b/drivers/hwmon/gpio-fan.c @@ -612,8 +612,11 @@ static void gpio_fan_shutdown(struct platform_device *pdev) { struct gpio_fan_data *fan_data = platform_get_drvdata(pdev); - if (fan_data->gpios) + if (fan_data->gpios) { + mutex_lock(&fan_data->lock); set_fan_speed(fan_data, 0); + mutex_unlock(&fan_data->lock); + } } static int gpio_fan_runtime_suspend(struct device *dev) |