gpiolib: introduce fwnode_gpiod_get_index()

This introduces fwnode_gpiod_get_index() that iterates through common gpio
suffixes when trying to locate a GPIO within a given firmware node.

We also switch devm_fwnode_gpiod_get_index() to call
fwnode_gpiod_get_index() instead of iterating through GPIO suffixes on
its own.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Link: https://lore.kernel.org/r/20190913032240.50333-3-dmitry.torokhov@gmail.com
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Dmitry Torokhov 2019-09-12 20:22:39 -07:00 committed by Linus Walleij
parent 2d2f116d69
commit 13949fa9da
3 changed files with 62 additions and 15 deletions

View File

@ -205,29 +205,15 @@ struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
enum gpiod_flags flags,
const char *label)
{
char prop_name[32]; /* 32 is max size of property name */
struct gpio_desc **dr;
struct gpio_desc *desc;
unsigned int i;
dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
GFP_KERNEL);
if (!dr)
return ERR_PTR(-ENOMEM);
for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
if (con_id)
snprintf(prop_name, sizeof(prop_name), "%s-%s",
con_id, gpio_suffixes[i]);
else
snprintf(prop_name, sizeof(prop_name), "%s",
gpio_suffixes[i]);
desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
label);
if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
break;
}
desc = fwnode_gpiod_get_index(fwnode, con_id, index, flags, label);
if (IS_ERR(desc)) {
devres_free(dr);
return desc;

View File

@ -4324,6 +4324,54 @@ static int platform_gpio_count(struct device *dev, const char *con_id)
return count;
}
/**
* fwnode_gpiod_get_index - obtain a GPIO from firmware node
* @fwnode: handle of the firmware node
* @con_id: function within the GPIO consumer
* @index: index of the GPIO to obtain for the consumer
* @flags: GPIO initialization flags
* @label: label to attach to the requested GPIO
*
* This function can be used for drivers that get their configuration
* from opaque firmware.
*
* The function properly finds the corresponding GPIO using whatever is the
* underlying firmware interface and then makes sure that the GPIO
* descriptor is requested before it is returned to the caller.
*
* Returns:
* On successful request the GPIO pin is configured in accordance with
* provided @flags.
*
* In case of error an ERR_PTR() is returned.
*/
struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
const char *con_id, int index,
enum gpiod_flags flags,
const char *label)
{
struct gpio_desc *desc;
char prop_name[32]; /* 32 is max size of property name */
unsigned int i;
for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
if (con_id)
snprintf(prop_name, sizeof(prop_name), "%s-%s",
con_id, gpio_suffixes[i]);
else
snprintf(prop_name, sizeof(prop_name), "%s",
gpio_suffixes[i]);
desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
label);
if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
break;
}
return desc;
}
EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);
/**
* gpiod_count - return the number of GPIOs associated with a device / function
* or -ENOENT if no GPIO has been assigned to the requested function

View File

@ -176,6 +176,10 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
const char *propname, int index,
enum gpiod_flags dflags,
const char *label);
struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
const char *con_id, int index,
enum gpiod_flags flags,
const char *label);
struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
struct fwnode_handle *child,
const char *con_id, int index,
@ -531,6 +535,15 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
return ERR_PTR(-ENOSYS);
}
static inline
struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
const char *con_id, int index,
enum gpiod_flags flags,
const char *label)
{
return ERR_PTR(-ENOSYS);
}
static inline
struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
struct fwnode_handle *fwnode,