[PATCH 2/5] hwmon: (gpio-fan) Add missing mutex locks

From: Alexander Stein
Date: Mon Feb 10 2025 - 10:02:46 EST


set_fan_speed() is expected to be called with fan_data->lock being locked.
Add locking for proper synchronization.

Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
---
drivers/hwmon/gpio-fan.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c
index d92c536be9af7..b779240328d59 100644
--- a/drivers/hwmon/gpio-fan.c
+++ b/drivers/hwmon/gpio-fan.c
@@ -393,7 +393,12 @@ static int gpio_fan_set_cur_state(struct thermal_cooling_device *cdev,
if (state >= fan_data->num_speed)
return -EINVAL;

+ mutex_lock(&fan_data->lock);
+
set_fan_speed(fan_data, state);
+
+ mutex_unlock(&fan_data->lock);
+
return 0;
}

@@ -489,7 +494,11 @@ MODULE_DEVICE_TABLE(of, of_gpio_fan_match);

static void gpio_fan_stop(void *data)
{
+ struct gpio_fan_data *fan_data = data;
+
+ mutex_lock(&fan_data->lock);
set_fan_speed(data, 0);
+ mutex_unlock(&fan_data->lock);
}

static int gpio_fan_probe(struct platform_device *pdev)
@@ -562,7 +571,9 @@ static int gpio_fan_suspend(struct device *dev)

if (fan_data->gpios) {
fan_data->resume_speed = fan_data->speed_index;
+ mutex_lock(&fan_data->lock);
set_fan_speed(fan_data, 0);
+ mutex_unlock(&fan_data->lock);
}

return 0;
@@ -572,8 +583,11 @@ static int gpio_fan_resume(struct device *dev)
{
struct gpio_fan_data *fan_data = dev_get_drvdata(dev);

- if (fan_data->gpios)
+ if (fan_data->gpios) {
+ mutex_lock(&fan_data->lock);
set_fan_speed(fan_data, fan_data->resume_speed);
+ mutex_unlock(&fan_data->lock);
+ }

return 0;
}
--
2.34.1