Hi Daniel et al. On Tue, Aug 04, 2020 at 06:43:30PM +0200, daniel@ffwll.ch wrote:
On Sun, Aug 02, 2020 at 01:06:17PM +0200, Sam Ravnborg wrote:
Add get and set operations to incapsualte access to backlight properties.
One easy win is that the get/set operatiosn can be used when backlight is not included in the configuration, resulting in simpler code with less ifdef's and thus more readable code.
The set/get methods hides some of the confusing power states, limiting the power state to either ON or OFF for the drivers.
Signed-off-by: Sam Ravnborg sam@ravnborg.org Cc: Lee Jones lee.jones@linaro.org Cc: Daniel Thompson daniel.thompson@linaro.org Cc: Jingoo Han jingoohan1@gmail.com
include/linux/backlight.h | 72 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+)
diff --git a/include/linux/backlight.h b/include/linux/backlight.h index d683c053ec09..882ceea45ace 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -474,6 +474,78 @@ static inline int backlight_get_brightness(const struct backlight_device *bd) return bd->props.brightness; }
+/**
- backlight_get_actual_brightness - Returns the actual brightness
- On failure a negative error code is returned.
- */
+static inline int backlight_get_actual_brightness(struct backlight_device *bd) +{
- if (bd && bd->ops && bd->ops->get_brightness)
return bd->ops->get_brightness(bd);- else
return -EINVAL;+}
+/**
- backlight_get_max_brightness - Returns maximum brightness
- This helper operation is preferred over direct access to
- &backlight_properties.max_brightness
- Returns 0 if backlight_device is NULL
- */
+static inline int backlight_get_max_brightness(const struct backlight_device *bd) +{
- if (bd)
return bd->props.max_brightness;- else
return 0;+}
+/**
- backlight_set_brightness - Set the brightness to the specified value
- This helper operation is preferred over direct assignment to
- &backlight_properties.brightness.
- If backlight_device is NULL then silently exit.
- */
+static inline void backlight_set_brightness(struct backlight_device *bd, int brightness) +{
- if (bd)
bd->props.brightness = brightness;Looking at the drivers I think including a call to backlight_update_status would simplify a lot of code.
+}
+/**
- backlight_set_power_on - Set power state to ON.
- This helper operation is preferred over direct assignment to
- backlight_properties.power.
- If backlight_device is NULL then silently exit.
- */
+static inline void backlight_set_power_on(struct backlight_device *bd) +{
- if (bd)
bd->props.power = FB_BLANK_UNBLANK;+}
+/**
- backlight_set_power_off - Set power state to OFF.
- This helper operation is preferred over direct assignment to
- backlight_properties.power.
- If backlight_device is NULL then silently exit.
- */
+static inline void backlight_set_power_off(struct backlight_device *bd)
I'm not clear why we need these two above? I thought the long-term plan is only use backlight_enable/disable and then remove the tri-state power handling once everyone is converted over?
Or maybe I'm just confused about the goal here ...
My TODO for v2: - Check all get_brightness implmentations. Using backlight_get_brightness is wrong - find a better way Check that they do return the actual brightness and not just the copy from the backlight core - Get rid of all uses of power_on/off - this is just another way to disable backlight - so be explicit about it - Consolidate the backlight_set_brightness(); backlight_update() pattern to a helper - Look into a mipi helper for backlight - Consider if we can change the backlight core to use an u32 for brightness - Take a look at Daniels rambling about drm_connector and backlight - Convert some platform backlight drivers to updated interface - to verify that they do not add new demends
The above should address feedback from Daniel etc. Thanks! No promises when I get time to do it - this list was mostly to help myself so I did not forget.
Note: My ISP blocked my attempt to reply to PATCH 0 - so I replied to this with the TODO list.
Sam
-Daniel
+{
- if (bd)
bd->props.power = FB_BLANK_POWERDOWN;+}
struct backlight_device * backlight_device_register(const char *name, struct device *dev, void *devdata, const struct backlight_ops *ops, -- 2.25.1
-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel