drm/i915: don't touch the VDD when disabling the panel

I don't see a reason to touch VDD when we're disabling the panel:
since the panel is enabled, we don't need VDD. This saves a few sleep
calls from the vdd_on and vdd_off functions at every modeset.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=69693
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Fix the patch mangle wiggle has done ... Spotted by Paulo.
Also drop the runtime_pm_put call which now has to go due to different
patch ordering. Also from Paul.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_ddi.c

@@ -1165,7 +1165,7 @@ static void intel_ddi_post_disable(struct intel_encoder *intel_encoder)
 
 	if (type == INTEL_OUTPUT_EDP) {
 		struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
-		ironlake_edp_panel_vdd_on(intel_dp);
+
 		ironlake_edp_panel_off(intel_dp);
 	}
 

drivers/gpu/drm/i915/intel_dp.c

@@ -1239,24 +1239,17 @@ void ironlake_edp_panel_off(struct intel_dp *intel_dp)
 
 	DRM_DEBUG_KMS("Turn eDP power off\n");
 
-	WARN(!intel_dp->want_panel_vdd, "Need VDD to turn off panel\n");
-
 	pp = ironlake_get_pp_control(intel_dp);
 	/* We need to switch off panel power _and_ force vdd, for otherwise some
 	 * panels get very unhappy and cease to work. */
-	pp &= ~(POWER_TARGET_ON | EDP_FORCE_VDD | PANEL_POWER_RESET | EDP_BLC_ENABLE);
+	pp &= ~(POWER_TARGET_ON | PANEL_POWER_RESET | EDP_BLC_ENABLE);
 
 	pp_ctrl_reg = _pp_ctrl_reg(intel_dp);
 
 	I915_WRITE(pp_ctrl_reg, pp);
 	POSTING_READ(pp_ctrl_reg);
 
-	intel_dp->want_panel_vdd = false;
-
 	ironlake_wait_panel_off(intel_dp);
-
-	/* We got a reference when we enabled the VDD. */
-	intel_runtime_pm_put(dev_priv);
 }
 
 void ironlake_edp_backlight_on(struct intel_dp *intel_dp)
@@ -1781,7 +1774,6 @@ static void intel_disable_dp(struct intel_encoder *encoder)
 
 	/* Make sure the panel is off before trying to change the mode. But also
 	 * ensure that we have vdd while we switch off the panel. */
-	ironlake_edp_panel_vdd_on(intel_dp);
 	ironlake_edp_backlight_off(intel_dp);
 	intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
 	ironlake_edp_panel_off(intel_dp);