Maarten and Ville noticed that we are enabling backlight via DP aux very
early in the modeset_init path via the intel_dp_aux_setup_backlight()
function, since commit e7156c8339 ("drm/i915: Add Backlight Control using
DPCD for eDP connectors (v9)"). Looks like all we need to do during
_setup_backlight() is read the current brightness state instead of
modifying it.
v2: Rewrote commit message.
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Yetunde Adebisi <yetundex.adebisi@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Puthikorn Voravootivat <puthik@chromium.org>
Fixes: e7156c8339 ("drm/i915: Add Backlight Control using DPCD for eDP connectors (v9)")
Link: http://patchwork.freedesktop.org/patch/msgid/1497384239-2965-1-git-send-email-dhinakaran.pandiyan@intel.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
(cherry picked from commit f6262bda46)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1497895708-19422-1-git-send-email-dhinakaran.pandiyan@intel.com
This patch adds support for eDP backlight control using DPCD registers to
backlight hooks in intel_panel.
It checks for backlight control over AUX channel capability and sets up
function pointers to get and set the backlight brightness level if
supported.
v2: Moved backlight functions from intel_dp.c into a new file
intel_dp_aux_backlight.c. Also moved reading of eDP display control
registers to intel_dp_get_dpcd
v3: Correct some formatting mistakes
v4: Updated to use AUX backlight control if PWM control is not possible
(Jani)
v5: Moved call to initialize backlight registers to dp_aux_setup_backlight
v6: Check DP_EDP_BACKLIGHT_PIN_ENABLE_CAP is disabled before setting up AUX
backlight control. To fix BLM_PWM_ENABLE igt test warnings on bdw_ultra
v7: Add enable_dpcd_backlight module parameter.
v8: Rebase onto latest drm-intel-nightly branch
v9: Remove changes to intel_dp_dpcd_read_wake
Split addition edp_dpcd variable into a separate patch
Cc: Bob Paauwe <bob.j.paauwe@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Yetunde Adebisi <yetundex.adebisi@intel.com>
[Jani: whitepace changes to appease checkpatch]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1459865452-9138-4-git-send-email-yetundex.adebisi@intel.com
