diff options
| author |   Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2025-04-23 10:55:40 +0200 |
|---|---|---|
| committer |   Jiri Kosina <jkosina@suse.com> | 2025-04-24 12:07:55 +0200 |
| commit | 837b05fea0752ee900abe57253d9f79ca46dd227 (patch) | |
| tree | 66168a6bc2174118164d1fc6611d5a91625d5a85 /drivers/hid | |
| parent | HID: cp2112: destroy mutex on driver detach (diff) | |
| download | linux-rng-837b05fea0752ee900abe57253d9f79ca46dd227.tar.xz linux-rng-837b05fea0752ee900abe57253d9f79ca46dd227.zip | |
HID: cp2112: hold the lock for the entire direction_output() call
We currently take the lock, set direction to output, release it,
reacquire it and set the desired value. That doesn't look correct.
Introduce a helper function that sets the value without taking the lock
and use it where applicable in order to combine the critical sections.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Diffstat (limited to 'drivers/hid')
| -rw-r--r-- | drivers/hid/hid-cp2112.c | 23 |
1 files changed, 15 insertions, 8 deletions
diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c index a001b9acd2d4..408c865efdd4 100644 --- a/drivers/hid/hid-cp2112.c +++ b/drivers/hid/hid-cp2112.c @@ -17,6 +17,7 @@ */ #include <linux/bitops.h> +#include <linux/cleanup.h> #include <linux/gpio/driver.h> #include <linux/hid.h> #include <linux/hidraw.h> @@ -218,15 +219,13 @@ exit: return ret; } -static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value) +static void cp2112_gpio_set_unlocked(struct cp2112_device *dev, + unsigned int offset, int value) { - struct cp2112_device *dev = gpiochip_get_data(chip); struct hid_device *hdev = dev->hdev; u8 *buf = dev->in_out_buffer; int ret; - mutex_lock(&dev->lock); - buf[0] = CP2112_GPIO_SET; buf[1] = value ? CP2112_GPIO_ALL_GPIO_MASK : 0; buf[2] = BIT(offset); @@ -236,8 +235,16 @@ static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value) HID_REQ_SET_REPORT); if (ret < 0) hid_err(hdev, "error setting GPIO values: %d\n", ret); +} - mutex_unlock(&dev->lock); +static void cp2112_gpio_set(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct cp2112_device *dev = gpiochip_get_data(chip); + + guard(mutex)(&dev->lock); + + return cp2112_gpio_set_unlocked(dev, offset, value); } static int cp2112_gpio_get_all(struct gpio_chip *chip) @@ -306,13 +313,13 @@ static int cp2112_gpio_direction_output(struct gpio_chip *chip, goto fail; } - mutex_unlock(&dev->lock); - /* * Set gpio value when output direction is already set, * as specified in AN495, Rev. 0.2, cpt. 4.4 */ - cp2112_gpio_set(chip, offset, value); + cp2112_gpio_set_unlocked(dev, offset, value); + + mutex_unlock(&dev->lock); return 0; |