6.15-stable review patch. If anyone has any objections, please let me know.
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From: Mario Limonciello mario.limonciello@amd.com
[ Upstream commit 8b5f3a229a70d242322b78c8e13744ca00212def ]
[Why] DC and AC levels are advertised in a percentage, not a luminance.
[How] Scale DC and AC levels to supported values.
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4221 Reviewed-by: Alex Hung alex.hung@amd.com Signed-off-by: Mario Limonciello mario.limonciello@amd.com Signed-off-by: Wayne Lin wayne.lin@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 96118a0e1ffeb..389748c420b02 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -4834,6 +4834,7 @@ amdgpu_dm_register_backlight_device(struct amdgpu_dm_connector *aconnector) struct backlight_properties props = { 0 }; struct amdgpu_dm_backlight_caps caps = { 0 }; char bl_name[16]; + int min, max;
if (aconnector->bl_idx == -1) return; @@ -4846,11 +4847,15 @@ amdgpu_dm_register_backlight_device(struct amdgpu_dm_connector *aconnector) }
amdgpu_acpi_get_backlight_caps(&caps); - if (caps.caps_valid) { + if (caps.caps_valid && get_brightness_range(&caps, &min, &max)) { if (power_supply_is_system_supplied() > 0) - props.brightness = caps.ac_level; + props.brightness = (max - min) * DIV_ROUND_CLOSEST(caps.ac_level, 100); else - props.brightness = caps.dc_level; + props.brightness = (max - min) * DIV_ROUND_CLOSEST(caps.dc_level, 100); + /* min is zero, so max needs to be adjusted */ + props.max_brightness = max - min; + drm_dbg(drm, "Backlight caps: min: %d, max: %d, ac %d, dc %d\n", min, max, + caps.ac_level, caps.dc_level); } else props.brightness = AMDGPU_MAX_BL_LEVEL;