On Thu, Sep 28, 2017 at 06:19:35PM +0200, Noralf Trønnes wrote:
Den 28.09.2017 11.15, skrev Meghana Madhyastha:
Add devm_drm_of_find_backlight and the corresponding release function because some drivers such as tinydrm use devres versions of functions for requiring device resources.
Signed-off-by: Meghana Madhyastha meghana.madhyastha@gmail.com
Changes in v3: -None
drivers/gpu/drm/drm_of.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ include/drm/drm_of.h | 2 ++ 2 files changed, 50 insertions(+)
diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c index d878d3a..238e8e5 100644 --- a/drivers/gpu/drm/drm_of.c +++ b/drivers/gpu/drm/drm_of.c @@ -304,3 +304,51 @@ struct backlight_device *drm_of_find_backlight(struct device *dev) return backlight; } EXPORT_SYMBOL(drm_of_find_backlight);
+/**
- devm_drm_of_find_backlight_release - Release backlight device
- @dev: Device
- This is the release function corresponding to the devm_drm_of_find_backlight.
- Each devres entry is associated with a release function.
- */
This is an internal function so no need for docs or exporting. I know that some devm_ functions have explicit release functions, but I don't think this is necessary since those users can just use drm_of_find_backlight() directly instead.
I have a question here. devm_drm_of_find_backlight_release is a wrapper around put_device which is passed as a parameter to devm_add_action in devm_drm_of_find_backlight. So isn't the function useful here ?
+static void devm_drm_of_find_backlight_release(void *data) +{
- put_device(data);
+} +EXPORT_SYMBOL(devm_drm_of_find_backlight_release);
+/**
- devm_drm_of_find_backlight - Find backlight device in device-tree
- devres version of the function
- @dev: Device
- This is the devres version of the function drm_of_find_backlight.
- Some drivers such as tinydrm use devres versions of functions for
No need to mention tinydrm here.
- requiring device resources.
- Returns:
- NULL if there's no backlight property.
- Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
- is found.
- If the backlight device is found, a pointer to the structure is returned.
- */
+struct backlight_device *devm_drm_of_find_backlight(struct device *dev) +{
- struct backlight_device *backlight;
- int ret;
- backlight = drm_of_find_backlight(dev);
- if (IS_ERR_OR_NULL(backlight))
return backlight;- ret = devm_add_action(dev, devm_drm_of_find_backlight_release,
&backlight->dev);- if (ret) {
put_device(&backlight->dev);return ERR_PTR(ret);- }
- return backlight;
+} +EXPORT_SYMBOL(devm_drm_of_find_backlight); diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h index e8fba5b..071fb3b 100644 --- a/include/drm/drm_of.h +++ b/include/drm/drm_of.h @@ -30,7 +30,9 @@ int drm_of_find_panel_or_bridge(const struct device_node *np, struct drm_panel **panel, struct drm_bridge **bridge); struct backlight_device *drm_of_find_backlight(struct device *dev); +struct backlight_device *devm_drm_of_find_backlight(struct device *dev); #else
We need a dummy version of devm_drm_of_find_backlight() here that returns NULL as in the previous patch.
+static void devm_drm_of_find_backlight_release(void *data);
And this isn't needed as explained above.
static inline uint32_t drm_of_find_possible_crtcs(struct drm_device *dev, struct device_node *port) {
I'd appreciate if you could also switch mi0283qt over to this helper :-)
Noralf.