2023-06-24 09:09:40

by Jean-Jacques Hiblot

[permalink] [raw]
Subject: [PATCH v10 2/5] leds: provide devm_of_led_get_optional()

This version of devm_of_led_get() doesn't fail if a LED is not found.
Instead it returns a NULL pointer.

Signed-off-by: Jean-Jacques Hiblot <[email protected]>
Reviewed-by: Andy Shevchenko <[email protected]>
---
drivers/leds/led-class.c | 25 +++++++++++++++++++++++++
include/linux/leds.h | 2 ++
2 files changed, 27 insertions(+)

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 6dae56b914fe..eb1a8494dc5b 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -402,6 +402,31 @@ void led_remove_lookup(struct led_lookup_data *led_lookup)
}
EXPORT_SYMBOL_GPL(led_remove_lookup);

+/**
+ * devm_of_led_get_optional - Resource-managed request of an optional LED device
+ * @dev: LED consumer
+ * @index: index of the LED to obtain in the consumer
+ *
+ * The device node of the device is parsed to find the requested LED device.
+ * The LED device returned from this function is automatically released
+ * on driver detach.
+ *
+ * @return a pointer to a LED device, ERR_PTR(errno) on failure and NULL if the
+ * led was not found.
+ */
+struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev,
+ int index)
+{
+ struct led_classdev *led;
+
+ led = devm_of_led_get(dev, index);
+ if (IS_ERR(led) && PTR_ERR(led) == -ENOENT)
+ return NULL;
+
+ return led;
+}
+EXPORT_SYMBOL_GPL(devm_of_led_get_optional);
+
static int led_classdev_next_name(const char *init_name, char *name,
size_t len)
{
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 50b2f8f153fb..95311c70d95c 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -270,6 +270,8 @@ extern struct led_classdev *of_led_get(struct device_node *np, int index);
extern void led_put(struct led_classdev *led_cdev);
struct led_classdev *__must_check devm_of_led_get(struct device *dev,
int index);
+struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev,
+ int index);

/**
* led_blink_set - set blinking with software fallback
--
2.34.1



2023-07-13 10:29:32

by Lee Jones

[permalink] [raw]
Subject: Re: [PATCH v10 2/5] leds: provide devm_of_led_get_optional()

On Sat, 24 Jun 2023, Jean-Jacques Hiblot wrote:

> This version of devm_of_led_get() doesn't fail if a LED is not found.
> Instead it returns a NULL pointer.
>
> Signed-off-by: Jean-Jacques Hiblot <[email protected]>
> Reviewed-by: Andy Shevchenko <[email protected]>
> ---
> drivers/leds/led-class.c | 25 +++++++++++++++++++++++++
> include/linux/leds.h | 2 ++
> 2 files changed, 27 insertions(+)

What Markus said isn't wrong, but isn't a blocker either. He's just
repeating Linus' preferences with respect to commit logs. Ideally you
should be explaining what the problem is and what this patch does to
solve it in a manner that is more directing and less explanatory in the
past tense.

--
Lee Jones [李琼斯]