<div dir="ltr"><div class="gmail_extra"> <div class="gmail_quote">On Wed, May 17, 2017 at 1:09 PM, Pandiyan, Dhinakaran <<a href="mailto:dhinakaran.pandiyan@intel.com" target="_blank" class="cremed">dhinakaran.pandiyan@intel.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div> <div style="direction:ltr;font-family:Helvetica;color:#000000;font-size:10pt"> ________________________________________ From: Puthikorn Voravootivat [<a href="mailto:puthik@google.com" target="_blank" class="cremed">puthik@google.com</a>] on behalf of Puthikorn Voravootivat [<a href="mailto:puthik@chromium.org" target="_blank" class="cremed">puthik@chromium.org</a>] Sent: Tuesday, May 16, 2017 5:33 PM To: <a href="mailto:intel-gfx@lists.freedesktop.org" target="_blank" class="cremed">intel-gfx@lists.freedesktop.org</a>; Pandiyan, Dhinakaran Cc: <a href="mailto:dri-devel@lists.freedesktop.org" target="_blank" class="cremed">dri-devel@lists.freedesktop.org</a>; Jani Nikula; Navare, Manasi D; Stephane Marchesin; Puthikorn Voravootivat Subject: [PATCH v8 1/5] drm/i915: Drop AUX backlight enable check for backlight control<div><div class="h5"> There are some panel that (1) does not support display backlight enable via AUX (2) support display backlight adjustment via AUX (3) support display backlight enable via eDP BL_ENABLE pin The current driver required that (1) must be support to enable (2). This patch drops that requirement. Signed-off-by: Puthikorn Voravootivat <<a href="mailto:puthik@chromium.org" target="_blank" class="cremed">puthik@chromium.org</a>> --- drivers/gpu/drm/i915/intel_dp_aux_backlight.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c index b87c5a381d6a..d32c06583e0b 100644 --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c @@ -165,7 +165,6 @@ intel_dp_aux_display_control_capable(struct intel_connector *connector) * the panel can support backlight control over the aux channel */ if (intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP && - (intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) && (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP) && !((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_PIN_ENABLE_CAP) || (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP))) { -- 2.13.0.303.g4ebf302169-goog </div></div> ^ still has the problem I mentioned last time. How about this? diff --git a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c index b87c5a3..7072bcf 100644 --- a/drivers/gpu/drm/i915/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/intel_dp_aux_backlight.c @@ -28,6 +28,10 @@ static void set_aux_backlight_enable(struct intel_dp *intel_dp, bool enable) { uint8_t reg_val = 0; + /* Early return when display use other mechanism to enable backlight. */ + if (!(intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP)) + return; + if (drm_dp_dpcd_readb(&intel_dp->aux, DP_EDP_DISPLAY_CONTROL_REGISTER, &reg_val) < 0) { DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n", @@ -165,10 +169,8 @@ intel_dp_aux_display_control_capable(struct intel_connector *connector) * the panel can support backlight control over the aux channel */ if (intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP && - (intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_CAP) && (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP) && - !((intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_PIN_ENABLE_CAP) || - (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP))) { + !(intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_PWM_PIN_CAP)) { DRM_DEBUG_KMS("AUX Backlight Control Supported!\n"); return true; } </div> </div> </blockquote></div>This works too. I probably misunderstood your comment as I move the code to next patch in the set.</div></div>