diff mbox series

[v3,24/24] gpio: mark unsafe gpio_chip manipulators as deprecated

Message ID 20240208095920.8035-25-brgl@bgdev.pl
State New
Headers show
Series gpio: rework locking and object life-time control | expand

Commit Message

Bartosz Golaszewski Feb. 8, 2024, 9:59 a.m. UTC 
From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

We still have some functions that return the address of the GPIO chip
associated with the GPIO device. This is dangerous and the users should
find a better solution. Let's add appropriate comments to the kernel
docs.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpio/gpiolib.c | 6 ++++++
 1 file changed, 6 insertions(+)
diff mbox series

Patch

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 97829f0c8487..9f8cf064002d 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -211,6 +211,11 @@  EXPORT_SYMBOL_GPL(desc_to_gpio);
 /**
  * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
  * @desc:	descriptor to return the chip of
+ *
+ * *DEPRECATED*
+ * This function is unsafe and should not be used. Using the chip address
+ * without taking the SRCU read lock may result in dereferencing a dangling
+ * pointer.
  */
 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
 {
@@ -275,6 +280,7 @@  EXPORT_SYMBOL(gpio_device_get_label);
  * Returns:
  * Address of the GPIO chip backing this device.
  *
+ * *DEPRECATED*
  * Until we can get rid of all non-driver users of struct gpio_chip, we must
  * provide a way of retrieving the pointer to it from struct gpio_device. This
  * is *NOT* safe as the GPIO API is considered to be hot-unpluggable and the