drm/i915/sdvo: always set positive sync polarity

This is a revert of 81a14b46846fea0741902e8d8dfcc6c6c78154c8.

We already set the mode polarity using the SDVO commands with struct
intel_sdvo_dtd. We have at least 3 bugs that get fixed with this patch.
The documentation, despite not clear, can also be interpreted in a way
that suggests this patch is needed.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=15766
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42174
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=43333
Cc: stable@kernel.org
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 3 insertions, 5 deletions

diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index f7b9268df266..e334ec33a47d 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -1066,15 +1066,13 @@ static void intel_sdvo_mode_set(struct drm_encoder *encoder,
 
         /* Set the SDVO control regs. */
         if (INTEL_INFO(dev)->gen >= 4) {
-                sdvox = 0;
+                /* The real mode polarity is set by the SDVO commands, using
+                 * struct intel_sdvo_dtd. */
+                sdvox = SDVO_VSYNC_ACTIVE_HIGH | SDVO_HSYNC_ACTIVE_HIGH;
                 if (intel_sdvo->is_hdmi)
                         sdvox |= intel_sdvo->color_range;
                 if (INTEL_INFO(dev)->gen < 5)
                         sdvox |= SDVO_BORDER_ENABLE;
-                if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
-                        sdvox |= SDVO_VSYNC_ACTIVE_HIGH;
-                if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
-                        sdvox |= SDVO_HSYNC_ACTIVE_HIGH;
         } else {
                 sdvox = I915_READ(intel_sdvo->sdvo_reg);
                 switch (intel_sdvo->sdvo_reg) {