drm/i915: rip out intel_disable_pch_ports

Even with the old crtc helper code we should have disabled all
encoders on that pipe by now, and with the new code this would
definitely paper over a bug. We already have the necessary checks
in place in intel_disable_transcoder, so if we accidentally leave
a pch port on, this will be caught.

Hence just rip this all out.

Note that up to the patch in this giant modeset series that removes
the LVDS special case to avoid disabling LVDS in the encoder->prepare
callback ("drm/i915/lvds: ditch ->prepare special case"), this was not
the case for all outputs.

Also note that in

commit 1b3c7a47f993bf9ab6c4c7cc3bbf5588052b58f4
Author: Zhenyu Wang <zhenyuw@linux.intel.com>
Date:   Wed Nov 25 13:09:38 2009 +0800

    drm/i915: Fix LVDS stability issue on Ironlake

this was already discovered independently and worked around. How I
bloody hate this entire mess of cludges piled on top of other cludges.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -1860,59 +1860,6 @@ static void intel_disable_plane(struct drm_i915_private *dev_priv,
 	intel_wait_for_vblank(dev_priv->dev, pipe);
 }
 
-static void disable_pch_dp(struct drm_i915_private *dev_priv,
-			   enum pipe pipe, int reg, u32 port_sel)
-{
-	u32 val = I915_READ(reg);
-	if (dp_pipe_enabled(dev_priv, pipe, port_sel, val)) {
-		DRM_DEBUG_KMS("Disabling pch dp %x on pipe %d\n", reg, pipe);
-		I915_WRITE(reg, val & ~DP_PORT_EN);
-	}
-}
-
-static void disable_pch_hdmi(struct drm_i915_private *dev_priv,
-			     enum pipe pipe, int reg)
-{
-	u32 val = I915_READ(reg);
-	if (hdmi_pipe_enabled(dev_priv, pipe, val)) {
-		DRM_DEBUG_KMS("Disabling pch HDMI %x on pipe %d\n",
-			      reg, pipe);
-		I915_WRITE(reg, val & ~PORT_ENABLE);
-	}
-}
-
-/* Disable any ports connected to this transcoder */
-static void intel_disable_pch_ports(struct drm_i915_private *dev_priv,
-				    enum pipe pipe)
-{
-	u32 reg, val;
-
-	val = I915_READ(PCH_PP_CONTROL);
-	I915_WRITE(PCH_PP_CONTROL, val | PANEL_UNLOCK_REGS);
-
-	disable_pch_dp(dev_priv, pipe, PCH_DP_B, TRANS_DP_PORT_SEL_B);
-	disable_pch_dp(dev_priv, pipe, PCH_DP_C, TRANS_DP_PORT_SEL_C);
-	disable_pch_dp(dev_priv, pipe, PCH_DP_D, TRANS_DP_PORT_SEL_D);
-
-	reg = PCH_ADPA;
-	val = I915_READ(reg);
-	if (adpa_pipe_enabled(dev_priv, pipe, val))
-		I915_WRITE(reg, val & ~ADPA_DAC_ENABLE);
-
-	reg = PCH_LVDS;
-	val = I915_READ(reg);
-	if (lvds_pipe_enabled(dev_priv, pipe, val)) {
-		DRM_DEBUG_KMS("disable lvds on pipe %d val 0x%08x\n", pipe, val);
-		I915_WRITE(reg, val & ~LVDS_PORT_EN);
-		POSTING_READ(reg);
-		udelay(100);
-	}
-
-	disable_pch_hdmi(dev_priv, pipe, HDMIB);
-	disable_pch_hdmi(dev_priv, pipe, HDMIC);
-	disable_pch_hdmi(dev_priv, pipe, HDMID);
-}
-
 int
 intel_pin_and_fence_fb_obj(struct drm_device *dev,
 			   struct drm_i915_gem_object *obj,
@@ -3321,13 +3268,6 @@ static void ironlake_crtc_disable(struct drm_crtc *crtc)
 
 	ironlake_fdi_disable(crtc);
 
-	/* This is a horrible layering violation; we should be doing this in
-	 * the connector/encoder ->prepare instead, but we don't always have
-	 * enough information there about the config to know whether it will
-	 * actually be necessary or just cause undesired flicker.
-	 */
-	intel_disable_pch_ports(dev_priv, pipe);
-
 	intel_disable_transcoder(dev_priv, pipe);
 
 	if (HAS_PCH_CPT(dev)) {