diff options
| author | Hans de Goede <hdegoede@redhat.com> | 2022-05-16 16:04:17 +0200 |
|---|---|---|
| committer | Hans de Goede <hdegoede@redhat.com> | 2022-09-03 12:17:26 +0200 |
| commit | 5e0e33f92ea5d891ea37fbc5119031024c154805 (patch) | |
| tree | 98b5355b931cb69a06420773263bee1b2563342e /drivers/gpu/drm/radeon | |
| parent | c0f50c5de93b8afb2281009a33c124e82973e457 (diff) | |
| download | linux-5e0e33f92ea5d891ea37fbc5119031024c154805.tar.bz2 | |
drm/radeon: Register ACPI video backlight when skipping radeon backlight registration
Typically the acpi_video driver will initialize before radeon, which
used to cause /sys/class/backlight/acpi_video0 to get registered and then
radeon would register its own radeon_bl# device later. After which
the drivers/acpi/video_detect.c code unregistered the acpi_video0 device
to avoid there being 2 backlight devices.
This means that userspace used to briefly see 2 devices and the
disappearing of acpi_video0 after a brief time confuses the systemd
backlight level save/restore code, see e.g.:
https://bbs.archlinux.org/viewtopic.php?id=269920
To fix this the ACPI video code has been modified to make backlight class
device registration a separate step, relying on the drm/kms driver to
ask for the acpi_video backlight registration after it is done setting up
its native backlight device.
Add a call to the new acpi_video_register_backlight() when radeon skips
registering its own backlight device because of e.g. the firmware_flags
or the acpi_video_get_backlight_type() return value. This ensures that
if the acpi_video backlight device should be used, it will be available
before the radeon drm_device gets registered with userspace.
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Diffstat (limited to 'drivers/gpu/drm/radeon')
| -rw-r--r-- | drivers/gpu/drm/radeon/radeon_encoders.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_encoders.c b/drivers/gpu/drm/radeon/radeon_encoders.c index 46549d5179ee..c1cbebb51be1 100644 --- a/drivers/gpu/drm/radeon/radeon_encoders.c +++ b/drivers/gpu/drm/radeon/radeon_encoders.c @@ -30,6 +30,8 @@ #include <drm/drm_device.h> #include <drm/radeon_drm.h> +#include <acpi/video.h> + #include "radeon.h" #include "radeon_atombios.h" #include "radeon_legacy_encoders.h" @@ -167,7 +169,7 @@ static void radeon_encoder_add_backlight(struct radeon_encoder *radeon_encoder, return; if (radeon_backlight == 0) { - return; + use_bl = false; } else if (radeon_backlight == 1) { use_bl = true; } else if (radeon_backlight == -1) { @@ -193,6 +195,13 @@ static void radeon_encoder_add_backlight(struct radeon_encoder *radeon_encoder, else radeon_legacy_backlight_init(radeon_encoder, connector); } + + /* + * If there is no native backlight device (which may happen even when + * use_bl==true) try registering an ACPI video backlight device instead. + */ + if (!rdev->mode_info.bl_encoder) + acpi_video_register_backlight(); } void |