gpio: return NULL from gpiod_get_optional when GPIOLIB is disabled

Given the intent behind gpiod_get_optional() and friends it does not make
sense to return -ENOSYS when GPIOLIB is disabled: the driver is expected to
work just fine without gpio so let's behave as if gpio was not found.
Otherwise we have to special-case -ENOSYS in drivers.

Note that there was objection that someone might forget to enable GPIOLIB
when dealing with a platform that has device that actually specifies
optional gpio and we'll break it. I find this unconvincing as that would
have to be the *only GPIO* in the system, which is extremely unlikely.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Dmitry Torokhov
2017-02-12 17:13:55 -08:00
committed by Linus Walleij
parent 85c73d50e5
commit 22c403676d
2 changed files with 12 additions and 6 deletions

View File

@@ -179,14 +179,14 @@ static inline struct gpio_desc *__must_check
gpiod_get_optional(struct device *dev, const char *con_id,
enum gpiod_flags flags)
{
return ERR_PTR(-ENOSYS);
return NULL;
}
static inline struct gpio_desc *__must_check
gpiod_get_index_optional(struct device *dev, const char *con_id,
unsigned int index, enum gpiod_flags flags)
{
return ERR_PTR(-ENOSYS);
return NULL;
}
static inline struct gpio_descs *__must_check
@@ -200,7 +200,7 @@ static inline struct gpio_descs *__must_check
gpiod_get_array_optional(struct device *dev, const char *con_id,
enum gpiod_flags flags)
{
return ERR_PTR(-ENOSYS);
return NULL;
}
static inline void gpiod_put(struct gpio_desc *desc)
@@ -240,14 +240,14 @@ static inline struct gpio_desc *__must_check
devm_gpiod_get_optional(struct device *dev, const char *con_id,
enum gpiod_flags flags)
{
return ERR_PTR(-ENOSYS);
return NULL;
}
static inline struct gpio_desc *__must_check
devm_gpiod_get_index_optional(struct device *dev, const char *con_id,
unsigned int index, enum gpiod_flags flags)
{
return ERR_PTR(-ENOSYS);
return NULL;
}
static inline struct gpio_descs *__must_check
@@ -261,7 +261,7 @@ static inline struct gpio_descs *__must_check
devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
enum gpiod_flags flags)
{
return ERR_PTR(-ENOSYS);
return NULL;
}
static inline void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)