Am 8. September 2020 17:15:25 MESZ schrieb Pratyush Yadav p.yadav@ti.com:
On 08/09/20 04:12PM, Heinrich Schuchardt wrote:
On 08.09.20 07:40, Pratyush Yadav wrote:
From: Jean-Jacques Hiblot jjhiblot@ti.com
Add managed functions to get a gpio from the devce-tree, based on a property name (minus the '-gpios' suffix) and optionally an index.
When the device is unbound, the GPIO is automatically released and
the
data structure is freed.
Signed-off-by: Jean-Jacques Hiblot jjhiblot@ti.com Reviewed-by: Simon Glass sjg@chromium.org Signed-off-by: Pratyush Yadav p.yadav@ti.com
drivers/gpio/gpio-uclass.c | 71
++++++++++++++++++++++++++++++++++++++
include/asm-generic/gpio.h | 47 +++++++++++++++++++++++++ 2 files changed, 118 insertions(+)
diff --git a/drivers/gpio/gpio-uclass.c
b/drivers/gpio/gpio-uclass.c
index 9c53299b6a..0c01413b58 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -6,6 +6,8 @@ #include <common.h> #include <dm.h> #include <log.h> +#include <dm/devres.h> +#include <dm/device_compat.h> #include <dm/device-internal.h> #include <dm/lists.h> #include <dm/uclass-internal.h> @@ -1209,6 +1211,75 @@ int gpio_dev_request_index(struct udevice
*dev, const char *nodename,
flags, 0, dev);}
+static void devm_gpiod_release(struct udevice *dev, void *res) +{
- dm_gpio_free(dev, res);
+}
+static int devm_gpiod_match(struct udevice *dev, void *res, void
*data)
+{
- return res == data;
+}
+struct gpio_desc *devm_gpiod_get_index(struct udevice *dev, const
char *id,
unsigned int index, int flags)+{
- int rc;
- struct gpio_desc *desc;
- char *propname;
- static const char suffix[] = "-gpios";
- propname = malloc(strlen(id) + sizeof(suffix));
- if (!propname) {
rc = -ENOMEM;goto end;- }
- strcpy(propname, id);
- strcat(propname, suffix);
- desc = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc),
__GFP_ZERO);- if (unlikely(!desc)) {
rc = -ENOMEM;goto end;- }
- rc = gpio_request_by_name(dev, propname, index, desc, flags);
+end:
- if (propname)
free(propname);- if (rc)
return ERR_PTR(rc);- devres_add(dev, desc);
- return desc;
+}
+struct gpio_desc *devm_gpiod_get_index_optional(struct udevice
*dev,
const char *id,unsigned int index,int flags)+{
- struct gpio_desc *desc = devm_gpiod_get_index(dev, id, index,
flags);
- if (IS_ERR(desc))
return NULL;- return desc;
+}
+void devm_gpiod_put(struct udevice *dev, struct gpio_desc *desc) +{
- int rc;
- rc = devres_release(dev, devm_gpiod_release, devm_gpiod_match,
desc);
- WARN_ON(rc);
+}
static int gpio_post_bind(struct udevice *dev) { struct udevice *child; diff --git a/include/asm-generic/gpio.h
b/include/asm-generic/gpio.h
index a57dd2665c..ad6979a8ce 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -701,4 +701,51 @@ int gpio_get_number(const struct gpio_desc
*desc);
*/ int gpio_get_acpi(const struct gpio_desc *desc, struct acpi_gpio
*gpio);
+/**
- devm_gpiod_get_index - Resource-managed gpiod_get()
- @dev: GPIO consumer
- @con_id: function within the GPIO consumer
- @index: index of the GPIO to obtain in the consumer
- @flags: optional GPIO initialization flags
- Managed gpiod_get(). GPIO descriptors returned from this
function are
- automatically disposed on driver detach.
You pass in a device but write "driver detach". Shouldn't the object
be
"device" in the description as in your commit message?
Yes, it should be device.
Devices have methods remove() and unbind() but no detach. In the
commit
message you speak of unbind(). Please, don't use alternative
language.
Ok.
Please, include the API in the HTML documentation created by 'make htmldocs'.
I tried searching for the GPIO API documentation under doc/ but I can't
find anything. README.gpio doesn't mention it anywhere and doc/api/ has
no file for gpio. Where do I document the newly added APIs then?
Please, add a new file doc/api/gpio.rst and include your include there. Add gpio.rst to doc/api/index.rst.
Check that make htmldocs does not show warnings.
The documentation will be generated in doc/output.
Best regards
Heinrich
Why did you choose the unbind() and not the remove() event for
releasing
the GPIOs?
I did not. Whoever added the devres API did (git blames Masahiro Yamada). device_unbind() calls devres_release_all() so as a consequence
GPIO is released when the device is unbound.
Best regards
Heinrich
- Return the GPIO descriptor corresponding to the function con_id
of device
- dev, -ENOENT if no GPIO has been assigned to the requested
function, or
- another IS_ERR() code if an error occurred while trying to
acquire the GPIO.
- */
+struct gpio_desc *devm_gpiod_get_index(struct udevice *dev, const
char *id,
unsigned int index, int flags);+#define devm_gpiod_get(dev, id, flags) devm_gpiod_get_index(dev,
id, 0, flags)
+/**
- gpiod_get_optional - obtain an optional GPIO for a given GPIO
function
- @dev: GPIO consumer, can be NULL for system-global GPIOs
- @con_id: function within the GPIO consumer
- @index: index of the GPIO to obtain in the consumer
- @flags: optional GPIO initialization flags
- This is equivalent to devm_gpiod_get(), except that when no
GPIO was
- assigned to the requested function it will return NULL. This is
convenient
- for drivers that need to handle optional GPIOs.
- */
+struct gpio_desc *devm_gpiod_get_index_optional(struct udevice
*dev,
const char *id,unsigned int index,int flags);+#define devm_gpiod_get_optional(dev, id, flags) \
- devm_gpiod_get_index_optional(dev, id, 0, flags)
+/**
- devm_gpiod_put - Resource-managed gpiod_put()
- @dev: GPIO consumer
- @desc: GPIO descriptor to dispose of
- Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
- devm_gpiod_get_index(). Normally this function will not be
called as the GPIO
- will be disposed of by the resource management code.
- */
+void devm_gpiod_put(struct udevice *dev, struct gpio_desc *desc);
#endif /* _ASM_GENERIC_GPIO_H_ */
2.28.0