[PATCH v4 03/13] gpiolib: convert the type of hwnum to unsigned int in gpiochip_get_desc()

Bartosz Golaszewski
2019-12-24T12:07:27Z

From: Bartosz Golaszewski <bgolaszewski@baylibre.com>

gpiochip_get_desc() takes a u16 hwnum, but it turns out most users don't
respect that and usually pass an unsigned int. Since implicit casting to
a smaller type is dangerous - let's change the type of hwnum to unsigned
int in gpiochip_get_desc() and in gpiochip_request_own_desc() where the
size of hwnum is not respected either and who's a user of the former.

This is safe as we then check the hwnum against the number of lines
before proceeding in gpiochip_get_desc().

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
drivers/gpio/gpiolib.c | 5 +++--
drivers/gpio/gpiolib.h | 3 ++-
include/linux/gpio/driver.h | 3 ++-
3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 616e431039fc..68adbd2179a0 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -140,7 +140,7 @@ EXPORT_SYMBOL_GPL(gpio_to_desc);
* in the given chip for the specified hardware number.
*/
struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
- u16 hwnum)
+ unsigned int hwnum)
{
struct gpio_device *gdev = chip->gpiodev;

@@ -2990,7 +2990,8 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested);
* A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
* code on failure.
*/
-struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
+struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip,
+ unsigned int hwnum,
const char *label,
enum gpio_lookup_flags lflags,
enum gpiod_flags dflags)
diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
index ca9bc1e4803c..a1cbeabadc69 100644
--- a/drivers/gpio/gpiolib.h
+++ b/drivers/gpio/gpiolib.h
@@ -78,7 +78,8 @@ struct gpio_array {
unsigned long invert_mask[];
};

-struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
+struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
+ unsigned int hwnum);
int gpiod_get_array_value_complex(bool raw, bool can_sleep,
unsigned int array_size,
struct gpio_desc **desc_array,
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index e2480ef94c55..4f032de10bae 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -715,7 +715,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *chip)

#endif /* CONFIG_PINCTRL */

-struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
+struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip,
+ unsigned int hwnum,
const char *label,
enum gpio_lookup_flags lflags,
enum gpiod_flags dflags);
--
2.23.0