diff options
| author | Thierry Reding <treding@nvidia.com> | 2014-04-25 17:10:06 +0200 |
|---|---|---|
| committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2015-09-18 08:45:10 +0200 |
| commit | 8e23cf5068fd4c43d379cf5dd56cd9962aaf3241 (patch) | |
| tree | 47471d1e5e271028bdfb69f94807a2c6904b58b5 /Documentation | |
| parent | e9ad022e2f350086fda798bed07128f22e59d7b1 (diff) | |
gpio: Add helpers for optional GPIOs
Introduce gpiod_get_optional() and gpiod_get_index_optional() helpers
that make it easier for drivers to handle optional GPIOs.
Currently in order to handle optional GPIOs, a driver needs to special
case error handling for -ENOENT, such as this:
gpio = gpiod_get(dev, "foo");
if (IS_ERR(gpio)) {
if (PTR_ERR(gpio) != -ENOENT)
return PTR_ERR(gpio);
gpio = NULL;
}
if (gpio) {
/* set up GPIO */
}
With these new helpers the above is reduced to:
gpio = gpiod_get_optional(dev, "foo");
if (IS_ERR(gpio))
return PTR_ERR(gpio);
if (gpio) {
/* set up GPIO */
}
While at it, device-managed variants of these functions are also
provided.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
(cherry picked from commit 29a1f2333e07bbbecb920cc78fd035fe8f53207a)
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/driver-model/devres.txt | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt index 4f7897e99cba..10b8c5d2c797 100644 --- a/Documentation/driver-model/devres.txt +++ b/Documentation/driver-model/devres.txt @@ -308,3 +308,10 @@ SLAVE DMA ENGINE SPI devm_spi_register_master() + +GPIO + devm_gpiod_get() + devm_gpiod_get_index() + devm_gpiod_get_optional() + devm_gpiod_get_index_optional() + devm_gpiod_put() |