From: Mario Limonciello <[email protected]>
[Why]
FWTS autobrightness fails on eDP panels because actual_brightness can
read higher than the advertised max_brightness (e.g. 63576 vs 62451).
The conversion helpers expose the firmware PWM range to userspace as
[0..max]. But max_brightness is advertised as (max - min), which is
smaller. So reading the level can return a value above max_brightness.
This regressed in commit 4b61b8a39051 ("drm/amd/display: Add debugging
message for brightness caps"), which changed max_brightness to
(max - min) and undid commit 8dbd72cb7900 ("drm/amd/display: Export full
brightness range to userspace").
[How]
Advertise max_brightness as max, and scale the initial AC/DC brightness
against max too. Update the KUnit expectations to match.
Fixes: 4b61b8a39051 ("drm/amd/display: Add debugging message for brightness
caps")
Cc: [email protected]
Reviewed-by: Alex Hung <[email protected]>
Signed-off-by: Mario Limonciello <[email protected]>
Signed-off-by: George Zhang <[email protected]>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c | 6 +++---
.../display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c | 8 ++++----
2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c
index 11d54897a894..ca60c72855fd 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c
@@ -407,12 +407,12 @@ void amdgpu_dm_backlight_fill_props(const struct
amdgpu_dm_backlight_caps *caps,
if (get_brightness_range(caps, &min, &max)) {
if (is_system_supplied)
- props->brightness = DIV_ROUND_CLOSEST((max - min) *
caps->ac_level,
+ props->brightness = DIV_ROUND_CLOSEST(max *
caps->ac_level,
100);
else
- props->brightness = DIV_ROUND_CLOSEST((max - min) *
caps->dc_level,
+ props->brightness = DIV_ROUND_CLOSEST(max *
caps->dc_level,
100);
- props->max_brightness = max - min;
+ props->max_brightness = max;
} else {
props->brightness = MAX_BACKLIGHT_LEVEL;
props->max_brightness = MAX_BACKLIGHT_LEVEL;
diff --git
a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c
b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c
index adb896022a27..8ebc0f263e3e 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c
@@ -799,8 +799,8 @@ static void dm_test_backlight_fill_props_ac_linear(struct
kunit *test)
amdgpu_dm_backlight_fill_props(&caps, true, false, &props);
KUNIT_EXPECT_EQ(test, props.brightness,
- DIV_ROUND_CLOSEST((max - min) * caps.ac_level, 100));
- KUNIT_EXPECT_EQ(test, props.max_brightness, max - min);
+ DIV_ROUND_CLOSEST(max * caps.ac_level, 100));
+ KUNIT_EXPECT_EQ(test, props.max_brightness, max);
KUNIT_EXPECT_EQ(test, props.scale, BACKLIGHT_SCALE_LINEAR);
KUNIT_EXPECT_EQ(test, props.type, BACKLIGHT_RAW);
}
@@ -825,8 +825,8 @@ static void
dm_test_backlight_fill_props_dc_nonlinear(struct kunit *test)
amdgpu_dm_backlight_fill_props(&caps, false, true, &props);
KUNIT_EXPECT_EQ(test, props.brightness,
- DIV_ROUND_CLOSEST((max - min) * caps.dc_level, 100));
- KUNIT_EXPECT_EQ(test, props.max_brightness, max - min);
+ DIV_ROUND_CLOSEST(max * caps.dc_level, 100));
+ KUNIT_EXPECT_EQ(test, props.max_brightness, max);
KUNIT_EXPECT_EQ(test, props.scale, BACKLIGHT_SCALE_NON_LINEAR);
KUNIT_EXPECT_EQ(test, props.type, BACKLIGHT_RAW);
}
--
2.55.0
