diff options
| author | Suraj Kandpal <suraj.kandpal@intel.com> | 2025-06-20 12:04:40 +0530 |
|---|---|---|
| committer | Suraj Kandpal <suraj.kandpal@intel.com> | 2025-06-30 20:41:46 +0530 |
| commit | f2db78e37fe7f95dde96abe2a2a8412f8f519658 (patch) | |
| tree | dc789a18ace6101a24d78e8f7b617d965a70b2b0 | |
| parent | 2ff7f0c381c15f457f83439bfdf5823fb33fb436 (diff) | |
drm/dp: Modify drm_edp_backlight_set_level
Modify drm_edp_backlight_set_level to be able to set the value
for register in DP_EDP_PANEL_TARGET_LUMINANCE_VALUE. We multiply
the level with 1000 since we get the value in Nits and the
register accepts it in milliNits.
--v2
-Add comment regarding the unit [Arun]
Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Arun R Murthy <arun.r.murthy@intel.com>
Link: https://lore.kernel.org/r/20250620063445.3603086-9-suraj.kandpal@intel.com
| -rw-r--r-- | drivers/gpu/drm/display/drm_dp_helper.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index c22d97e0f187..c29c327a72af 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -3944,20 +3944,28 @@ int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_bac u32 level) { int ret; - u8 buf[2] = { 0 }; + unsigned int offset = DP_EDP_BACKLIGHT_BRIGHTNESS_MSB; + u8 buf[3] = { 0 }; /* The panel uses the PWM for controlling brightness levels */ - if (!bl->aux_set) + if (!(bl->aux_set || bl->luminance_set)) return 0; - if (bl->lsb_reg_used) { + if (bl->luminance_set) { + level = level * 1000; + level &= 0xffffff; + buf[0] = (level & 0x0000ff); + buf[1] = (level & 0x00ff00) >> 8; + buf[2] = (level & 0xff0000) >> 16; + offset = DP_EDP_PANEL_TARGET_LUMINANCE_VALUE; + } else if (bl->lsb_reg_used) { buf[0] = (level & 0xff00) >> 8; buf[1] = (level & 0x00ff); } else { buf[0] = level; } - ret = drm_dp_dpcd_write_data(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf, sizeof(buf)); + ret = drm_dp_dpcd_write_data(aux, offset, buf, sizeof(buf)); if (ret < 0) { drm_err(aux->drm_dev, "%s: Failed to write aux backlight level: %d\n", |