When video.use_native_backlight=1 and non intel gfx are in use, the raw backlight device of the gfx driver will show up after acpi-video has done its acpi_video_verify_backlight_support() check.
This causes video.use_native_backlight=1 to not have the desired result.
This patch fixes this by adding a backlight notifier and when a raw backlight is registered or unregistered re-doing the acpi_video_verify_backlight_support() check.
Signed-off-by: Hans de Goede hdegoede@redhat.com --- drivers/acpi/video.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+)
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index ba6e4d7..47b7e21 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -151,6 +151,7 @@ struct acpi_video_enumerated_device { struct acpi_video_bus { struct acpi_device *device; bool backlight_registered; + bool backlight_notifier_registered; u8 dos_setting; struct acpi_video_enumerated_device *attached_array; u8 attached_count; @@ -162,6 +163,7 @@ struct acpi_video_bus { struct input_dev *input; char phys[32]; /* for input device */ struct notifier_block pm_nb; + struct notifier_block backlight_nb; };
struct acpi_video_device_flags { @@ -1828,6 +1830,9 @@ static int acpi_video_bus_register_backlight(struct acpi_video_bus *video) { struct acpi_video_device *dev;
+ if (video->backlight_registered) + return 0; + if (!acpi_video_verify_backlight_support()) return 0;
@@ -1972,6 +1977,56 @@ static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video) video->input = NULL; }
+static int acpi_video_backlight_notify(struct notifier_block *nb, + unsigned long val, void *bd) +{ + struct backlight_device *backlight = bd; + struct acpi_video_bus *video; + + /* acpi_video_verify_backlight_support only cares about raw devices */ + if (backlight->props.type != BACKLIGHT_RAW) + return NOTIFY_DONE; + + video = container_of(nb, struct acpi_video_bus, backlight_nb); + + switch (val) { + case BACKLIGHT_REGISTERED: + if (!acpi_video_verify_backlight_support()) + acpi_video_bus_unregister_backlight(video); + break; + case BACKLIGHT_UNREGISTERED: + acpi_video_bus_register_backlight(video); + break; + } + + return NOTIFY_OK; +} + +static int acpi_video_bus_add_backlight_notify_handler( + struct acpi_video_bus *video) +{ + int error; + + video->backlight_nb.notifier_call = acpi_video_backlight_notify; + video->backlight_nb.priority = 0; + error = backlight_register_notifier(&video->backlight_nb); + if (error == 0) + video->backlight_notifier_registered = true; + + return error; +} + +static int acpi_video_bus_remove_backlight_notify_handler( + struct acpi_video_bus *video) +{ + if (!video->backlight_notifier_registered) + return 0; + + video->backlight_notifier_registered = false; + + return backlight_unregister_notifier(&video->backlight_nb); +} + static int acpi_video_bus_put_devices(struct acpi_video_bus *video) { struct acpi_video_device *dev, *next; @@ -2053,6 +2108,7 @@ static int acpi_video_bus_add(struct acpi_device *device)
acpi_video_bus_register_backlight(video); acpi_video_bus_add_notify_handler(video); + acpi_video_bus_add_backlight_notify_handler(video);
return 0;
@@ -2076,6 +2132,7 @@ static int acpi_video_bus_remove(struct acpi_device *device)
video = acpi_driver_data(device);
+ acpi_video_bus_remove_backlight_notify_handler(video); acpi_video_bus_remove_notify_handler(video); acpi_video_bus_unregister_backlight(video); acpi_video_bus_put_devices(video);