| Message ID | 20170622190339.142671-4-puthik@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Jun 22, 2017 at 12:03:39PM -0700, Puthikorn Voravootivat wrote: > This patch adds option to enable dynamic backlight for eDP > panel that supports this feature via DPCD register and > set minimum / maximum brightness to 0% and 100% of the > normal brightness. This patch causes a regression on my ThinkPad X1 Carbon Gen 4; with enable_dbc = true the backlight stays off; setting i915.enable_dbc=0 on boot makes things work properly again. > Signed-off-by: Puthikorn Voravootivat <puthik@chromium.org> > Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> > --- > drivers/gpu/drm/i915/i915_params.c | 5 +++++ > drivers/gpu/drm/i915/i915_params.h | 3 ++- > drivers/gpu/drm/i915/intel_dp_aux_backlight.c | 26 ++++++++++++++++++++++++++ > 3 files changed, 33 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c > index 5b5ab15d191f..88b9d3e6713a 100644 > --- a/drivers/gpu/drm/i915/i915_params.c > +++ b/drivers/gpu/drm/i915/i915_params.c > @@ -65,6 +65,7 @@ struct i915_params i915 __read_mostly = { > .inject_load_failure = 0, > .enable_dpcd_backlight = -1, > .enable_gvt = false, > + .enable_dbc = true, > }; > > module_param_named(modeset, i915.modeset, int, 0400); > @@ -254,3 +255,7 @@ MODULE_PARM_DESC(enable_dpcd_backlight, > module_param_named(enable_gvt, i915.enable_gvt, bool, 0400); > MODULE_PARM_DESC(enable_gvt, > "Enable support for Intel GVT-g graphics virtualization host support(default:false)"); > + > +module_param_named_unsafe(enable_dbc, i915.enable_dbc, bool, 0600); > +MODULE_PARM_DESC(enable_dbc, > + "Enable support for dynamic backlight control (default:true)"); > diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h > index 0d6cf9138dc4..057e203e6bda 100644 > --- a/drivers/gpu/drm/i915/i915_params.h > +++ b/drivers/gpu/drm/i915/i915_params.h > @@ -67,7 +67,8 @@ > func(bool, verbose_state_checks); \ > func(bool, nuclear_pageflip); \ > func(bool, enable_dp_mst); \ > - func(bool, enable_gvt) > + func(bool, enable_gvt); \ > + func(bool, enable_dbc) > > #define MEMBER(T, member) T member > struct i915_params { > diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > index fea161727c6e..b25cd88fc1c5 100644 > --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > @@ -173,6 +173,24 @@ static bool intel_dp_aux_set_pwm_freq(struct intel_connector *connector) > return true; > } > > +/* > +* Set minimum / maximum dynamic brightness percentage. This value is expressed > +* as the percentage of normal brightness in 5% increments. > +*/ > +static bool > +intel_dp_aux_set_dynamic_backlight_percent(struct intel_dp *intel_dp, > + u32 min, u32 max) > +{ > + u8 dbc[] = { DIV_ROUND_CLOSEST(min, 5), DIV_ROUND_CLOSEST(max, 5) }; > + > + if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_DBC_MINIMUM_BRIGHTNESS_SET, > + dbc, sizeof(dbc)) < 0) { > + DRM_DEBUG_KMS("Failed to write aux DBC brightness level\n"); > + return false; > + } > + return true; > +} > + > static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_state, > const struct drm_connector_state *conn_state) > { > @@ -208,6 +226,14 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st > if (intel_dp_aux_set_pwm_freq(connector)) > new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; > > + if (i915.enable_dbc && > + (intel_dp->edp_dpcd[2] & DP_EDP_DYNAMIC_BACKLIGHT_CAP)) { > + if(intel_dp_aux_set_dynamic_backlight_percent(intel_dp, 0, 100)) { > + new_dpcd_buf |= DP_EDP_DYNAMIC_BACKLIGHT_ENABLE; > + DRM_DEBUG_KMS("Enable dynamic brightness.\n"); > + } > + } > + > if (new_dpcd_buf != dpcd_buf) { > if (drm_dp_dpcd_writeb(&intel_dp->aux, > DP_EDP_BACKLIGHT_MODE_SET_REGISTER, new_dpcd_buf) < 0) { > -- > 2.13.1.611.g7e3b11ae1-goog > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
On Mon, Jun 26, 2017 at 05:18:19PM +0300, David Weinehall wrote: > On Thu, Jun 22, 2017 at 12:03:39PM -0700, Puthikorn Voravootivat wrote: > > This patch adds option to enable dynamic backlight for eDP > > panel that supports this feature via DPCD register and > > set minimum / maximum brightness to 0% and 100% of the > > normal brightness. > > This patch causes a regression on my ThinkPad X1 Carbon Gen 4; > with enable_dbc = true the backlight stays off; setting i915.enable_dbc=0 > on boot makes things work properly again. Some more testing indicates that while i915.enable_dbc=0 solves the initial issue of backlight not coming on, it's not enough--after suspend/resume the backlight stays off. Passing i915.enable_dpcd_backlight=0 seems to work both for the initial case of backlight not coming on at boot, and the issue with backlight not coming on after suspend/resume. So: DBC:1, DPCD: -1: blank screen on boot DBC:0, DPCD: -1: screen OK on boot, blank after suspend/resume DBC:1, DPCD: 0: screen OK on boot, screen OK after suspend/resume DBC:0, DPCD: 0: screen OK on boot, screen OK after suspend/resume So it seems that at least for the ThinkPad X1 Carbon Gen 4 (possibly limited to the 2560x1440 model) DPCD backlight isn't supported. Or possibly something is wrong with the DPCD backlight patch. > > Signed-off-by: Puthikorn Voravootivat <puthik@chromium.org> > > Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> > > --- > > drivers/gpu/drm/i915/i915_params.c | 5 +++++ > > drivers/gpu/drm/i915/i915_params.h | 3 ++- > > drivers/gpu/drm/i915/intel_dp_aux_backlight.c | 26 ++++++++++++++++++++++++++ > > 3 files changed, 33 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c > > index 5b5ab15d191f..88b9d3e6713a 100644 > > --- a/drivers/gpu/drm/i915/i915_params.c > > +++ b/drivers/gpu/drm/i915/i915_params.c > > @@ -65,6 +65,7 @@ struct i915_params i915 __read_mostly = { > > .inject_load_failure = 0, > > .enable_dpcd_backlight = -1, > > .enable_gvt = false, > > + .enable_dbc = true, > > }; > > > > module_param_named(modeset, i915.modeset, int, 0400); > > @@ -254,3 +255,7 @@ MODULE_PARM_DESC(enable_dpcd_backlight, > > module_param_named(enable_gvt, i915.enable_gvt, bool, 0400); > > MODULE_PARM_DESC(enable_gvt, > > "Enable support for Intel GVT-g graphics virtualization host support(default:false)"); > > + > > +module_param_named_unsafe(enable_dbc, i915.enable_dbc, bool, 0600); > > +MODULE_PARM_DESC(enable_dbc, > > + "Enable support for dynamic backlight control (default:true)"); > > diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h > > index 0d6cf9138dc4..057e203e6bda 100644 > > --- a/drivers/gpu/drm/i915/i915_params.h > > +++ b/drivers/gpu/drm/i915/i915_params.h > > @@ -67,7 +67,8 @@ > > func(bool, verbose_state_checks); \ > > func(bool, nuclear_pageflip); \ > > func(bool, enable_dp_mst); \ > > - func(bool, enable_gvt) > > + func(bool, enable_gvt); \ > > + func(bool, enable_dbc) > > > > #define MEMBER(T, member) T member > > struct i915_params { > > diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > > index fea161727c6e..b25cd88fc1c5 100644 > > --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > > +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > > @@ -173,6 +173,24 @@ static bool intel_dp_aux_set_pwm_freq(struct intel_connector *connector) > > return true; > > } > > > > +/* > > +* Set minimum / maximum dynamic brightness percentage. This value is expressed > > +* as the percentage of normal brightness in 5% increments. > > +*/ > > +static bool > > +intel_dp_aux_set_dynamic_backlight_percent(struct intel_dp *intel_dp, > > + u32 min, u32 max) > > +{ > > + u8 dbc[] = { DIV_ROUND_CLOSEST(min, 5), DIV_ROUND_CLOSEST(max, 5) }; > > + > > + if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_DBC_MINIMUM_BRIGHTNESS_SET, > > + dbc, sizeof(dbc)) < 0) { > > + DRM_DEBUG_KMS("Failed to write aux DBC brightness level\n"); > > + return false; > > + } > > + return true; > > +} > > + > > static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_state, > > const struct drm_connector_state *conn_state) > > { > > @@ -208,6 +226,14 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st > > if (intel_dp_aux_set_pwm_freq(connector)) > > new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; > > > > + if (i915.enable_dbc && > > + (intel_dp->edp_dpcd[2] & DP_EDP_DYNAMIC_BACKLIGHT_CAP)) { > > + if(intel_dp_aux_set_dynamic_backlight_percent(intel_dp, 0, 100)) { > > + new_dpcd_buf |= DP_EDP_DYNAMIC_BACKLIGHT_ENABLE; > > + DRM_DEBUG_KMS("Enable dynamic brightness.\n"); > > + } > > + } > > + > > if (new_dpcd_buf != dpcd_buf) { > > if (drm_dp_dpcd_writeb(&intel_dp->aux, > > DP_EDP_BACKLIGHT_MODE_SET_REGISTER, new_dpcd_buf) < 0) { > > -- > > 2.13.1.611.g7e3b11ae1-goog > > > > _______________________________________________ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
On Tue, 2017-06-27 at 16:23 +0300, David Weinehall wrote: > On Mon, Jun 26, 2017 at 05:18:19PM +0300, David Weinehall wrote: > > On Thu, Jun 22, 2017 at 12:03:39PM -0700, Puthikorn Voravootivat wrote: > > > This patch adds option to enable dynamic backlight for eDP > > > panel that supports this feature via DPCD register and > > > set minimum / maximum brightness to 0% and 100% of the > > > normal brightness. > > > > This patch causes a regression on my ThinkPad X1 Carbon Gen 4; > > with enable_dbc = true the backlight stays off; setting i915.enable_dbc=0 > > on boot makes things work properly again. > > Some more testing indicates that while i915.enable_dbc=0 solves the > initial issue of backlight not coming on, it's not enough--after > suspend/resume the backlight stays off. > > Passing i915.enable_dpcd_backlight=0 seems to work both for the initial > case of backlight not coming on at boot, and the issue with backlight > not coming on after suspend/resume. > > So: > > DBC:1, DPCD: -1: blank screen on boot > DBC:0, DPCD: -1: screen OK on boot, blank after suspend/resume > DBC:1, DPCD: 0: screen OK on boot, screen OK after suspend/resume > DBC:0, DPCD: 0: screen OK on boot, screen OK after suspend/resume > > So it seems that at least for the ThinkPad X1 Carbon Gen 4 (possibly > limited to the 2560x1440 model) DPCD backlight isn't supported. > Hi David, Thanks for the bug report. It's come a bit sooner than I expected though. We shouldn't be enabling DPCD backlight control if the panel does not support it. I'd like to look at the dmesg with drm.debug=0xE. We debug log the panel capabilities early during boot and that will be useful. Can you also provide the output of i915_dpcd in debugfs for the eDP connector? I guess it makes sense to file an FDO and attach the logs there. -DK > Or possibly something is wrong with the DPCD backlight patch. > > > > Signed-off-by: Puthikorn Voravootivat <puthik@chromium.org> > > > Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> > > > --- > > > drivers/gpu/drm/i915/i915_params.c | 5 +++++ > > > drivers/gpu/drm/i915/i915_params.h | 3 ++- > > > drivers/gpu/drm/i915/intel_dp_aux_backlight.c | 26 ++++++++++++++++++++++++++ > > > 3 files changed, 33 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c > > > index 5b5ab15d191f..88b9d3e6713a 100644 > > > --- a/drivers/gpu/drm/i915/i915_params.c > > > +++ b/drivers/gpu/drm/i915/i915_params.c > > > @@ -65,6 +65,7 @@ struct i915_params i915 __read_mostly = { > > > .inject_load_failure = 0, > > > .enable_dpcd_backlight = -1, > > > .enable_gvt = false, > > > + .enable_dbc = true, > > > }; > > > > > > module_param_named(modeset, i915.modeset, int, 0400); > > > @@ -254,3 +255,7 @@ MODULE_PARM_DESC(enable_dpcd_backlight, > > > module_param_named(enable_gvt, i915.enable_gvt, bool, 0400); > > > MODULE_PARM_DESC(enable_gvt, > > > "Enable support for Intel GVT-g graphics virtualization host support(default:false)"); > > > + > > > +module_param_named_unsafe(enable_dbc, i915.enable_dbc, bool, 0600); > > > +MODULE_PARM_DESC(enable_dbc, > > > + "Enable support for dynamic backlight control (default:true)"); > > > diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h > > > index 0d6cf9138dc4..057e203e6bda 100644 > > > --- a/drivers/gpu/drm/i915/i915_params.h > > > +++ b/drivers/gpu/drm/i915/i915_params.h > > > @@ -67,7 +67,8 @@ > > > func(bool, verbose_state_checks); \ > > > func(bool, nuclear_pageflip); \ > > > func(bool, enable_dp_mst); \ > > > - func(bool, enable_gvt) > > > + func(bool, enable_gvt); \ > > > + func(bool, enable_dbc) > > > > > > #define MEMBER(T, member) T member > > > struct i915_params { > > > diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > > > index fea161727c6e..b25cd88fc1c5 100644 > > > --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > > > +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c > > > @@ -173,6 +173,24 @@ static bool intel_dp_aux_set_pwm_freq(struct intel_connector *connector) > > > return true; > > > } > > > > > > +/* > > > +* Set minimum / maximum dynamic brightness percentage. This value is expressed > > > +* as the percentage of normal brightness in 5% increments. > > > +*/ > > > +static bool > > > +intel_dp_aux_set_dynamic_backlight_percent(struct intel_dp *intel_dp, > > > + u32 min, u32 max) > > > +{ > > > + u8 dbc[] = { DIV_ROUND_CLOSEST(min, 5), DIV_ROUND_CLOSEST(max, 5) }; > > > + > > > + if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_DBC_MINIMUM_BRIGHTNESS_SET, > > > + dbc, sizeof(dbc)) < 0) { > > > + DRM_DEBUG_KMS("Failed to write aux DBC brightness level\n"); > > > + return false; > > > + } > > > + return true; > > > +} > > > + > > > static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_state, > > > const struct drm_connector_state *conn_state) > > > { > > > @@ -208,6 +226,14 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st > > > if (intel_dp_aux_set_pwm_freq(connector)) > > > new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; > > > > > > + if (i915.enable_dbc && > > > + (intel_dp->edp_dpcd[2] & DP_EDP_DYNAMIC_BACKLIGHT_CAP)) { > > > + if(intel_dp_aux_set_dynamic_backlight_percent(intel_dp, 0, 100)) { > > > + new_dpcd_buf |= DP_EDP_DYNAMIC_BACKLIGHT_ENABLE; > > > + DRM_DEBUG_KMS("Enable dynamic brightness.\n"); > > > + } > > > + } > > > + > > > if (new_dpcd_buf != dpcd_buf) { > > > if (drm_dp_dpcd_writeb(&intel_dp->aux, > > > DP_EDP_BACKLIGHT_MODE_SET_REGISTER, new_dpcd_buf) < 0) { > > > -- > > > 2.13.1.611.g7e3b11ae1-goog > > > > > > _______________________________________________ > > > Intel-gfx mailing list > > > Intel-gfx@lists.freedesktop.org > > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx > > _______________________________________________ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
On Tue, Jun 27, 2017 at 10:29:33PM +0000, Pandiyan, Dhinakaran wrote: > > > > On Tue, 2017-06-27 at 16:23 +0300, David Weinehall wrote: > > On Mon, Jun 26, 2017 at 05:18:19PM +0300, David Weinehall wrote: > > > On Thu, Jun 22, 2017 at 12:03:39PM -0700, Puthikorn Voravootivat wrote: > > > > This patch adds option to enable dynamic backlight for eDP > > > > panel that supports this feature via DPCD register and > > > > set minimum / maximum brightness to 0% and 100% of the > > > > normal brightness. > > > > > > This patch causes a regression on my ThinkPad X1 Carbon Gen 4; > > > with enable_dbc = true the backlight stays off; setting i915.enable_dbc=0 > > > on boot makes things work properly again. > > > > Some more testing indicates that while i915.enable_dbc=0 solves the > > initial issue of backlight not coming on, it's not enough--after > > suspend/resume the backlight stays off. > > > > Passing i915.enable_dpcd_backlight=0 seems to work both for the initial > > case of backlight not coming on at boot, and the issue with backlight > > not coming on after suspend/resume. > > > > So: > > > > DBC:1, DPCD: -1: blank screen on boot > > DBC:0, DPCD: -1: screen OK on boot, blank after suspend/resume > > DBC:1, DPCD: 0: screen OK on boot, screen OK after suspend/resume > > DBC:0, DPCD: 0: screen OK on boot, screen OK after suspend/resume > > > > So it seems that at least for the ThinkPad X1 Carbon Gen 4 (possibly > > limited to the 2560x1440 model) DPCD backlight isn't supported. > > > > Hi David, > > Thanks for the bug report. It's come a bit sooner than I expected > though. > > We shouldn't be enabling DPCD backlight control if the panel does not > support it. I'd like to look at the dmesg with drm.debug=0xE. We debug > log the panel capabilities early during boot and that will be useful. > Can you also provide the output of i915_dpcd in debugfs for the eDP > connector? > > I guess it makes sense to file an FDO and attach the logs there. https://bugs.freedesktop.org/show_bug.cgi?id=101619 Kind regards, David
diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index 5b5ab15d191f..88b9d3e6713a 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -65,6 +65,7 @@ struct i915_params i915 __read_mostly = { .inject_load_failure = 0, .enable_dpcd_backlight = -1, .enable_gvt = false, + .enable_dbc = true, }; module_param_named(modeset, i915.modeset, int, 0400); @@ -254,3 +255,7 @@ MODULE_PARM_DESC(enable_dpcd_backlight, module_param_named(enable_gvt, i915.enable_gvt, bool, 0400); MODULE_PARM_DESC(enable_gvt, "Enable support for Intel GVT-g graphics virtualization host support(default:false)"); + +module_param_named_unsafe(enable_dbc, i915.enable_dbc, bool, 0600); +MODULE_PARM_DESC(enable_dbc, + "Enable support for dynamic backlight control (default:true)"); diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h index 0d6cf9138dc4..057e203e6bda 100644 --- a/drivers/gpu/drm/i915/i915_params.h +++ b/drivers/gpu/drm/i915/i915_params.h @@ -67,7 +67,8 @@ func(bool, verbose_state_checks); \ func(bool, nuclear_pageflip); \ func(bool, enable_dp_mst); \ - func(bool, enable_gvt) + func(bool, enable_gvt); \ + func(bool, enable_dbc) #define MEMBER(T, member) T member struct i915_params { diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c index fea161727c6e..b25cd88fc1c5 100644 --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c @@ -173,6 +173,24 @@ static bool intel_dp_aux_set_pwm_freq(struct intel_connector *connector) return true; } +/* +* Set minimum / maximum dynamic brightness percentage. This value is expressed +* as the percentage of normal brightness in 5% increments. +*/ +static bool +intel_dp_aux_set_dynamic_backlight_percent(struct intel_dp *intel_dp, + u32 min, u32 max) +{ + u8 dbc[] = { DIV_ROUND_CLOSEST(min, 5), DIV_ROUND_CLOSEST(max, 5) }; + + if (drm_dp_dpcd_write(&intel_dp->aux, DP_EDP_DBC_MINIMUM_BRIGHTNESS_SET, + dbc, sizeof(dbc)) < 0) { + DRM_DEBUG_KMS("Failed to write aux DBC brightness level\n"); + return false; + } + return true; +} + static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_state, const struct drm_connector_state *conn_state) { @@ -208,6 +226,14 @@ static void intel_dp_aux_enable_backlight(const struct intel_crtc_state *crtc_st if (intel_dp_aux_set_pwm_freq(connector)) new_dpcd_buf |= DP_EDP_BACKLIGHT_FREQ_AUX_SET_ENABLE; + if (i915.enable_dbc && + (intel_dp->edp_dpcd[2] & DP_EDP_DYNAMIC_BACKLIGHT_CAP)) { + if(intel_dp_aux_set_dynamic_backlight_percent(intel_dp, 0, 100)) { + new_dpcd_buf |= DP_EDP_DYNAMIC_BACKLIGHT_ENABLE; + DRM_DEBUG_KMS("Enable dynamic brightness.\n"); + } + } + if (new_dpcd_buf != dpcd_buf) { if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER, new_dpcd_buf) < 0) {