drm/i915: Unbreak check_digital_port_conflicts()

Atomic changes broke check_digital_port_conflicts(). It needs to look
at the global situation instead of just trying to find a conflict
within the current atomic state.

This bug made my HSW explode spectacularly after I had split the DDI
encoders into separate DP and HDMI encoders. With the fix, things
seem much more solid.

I hope holding the connection_mutex is enough protection that we can
actually walk the connectors even if they're not part of the current
atomic state...

v2: Regenerate the patch so that it actually applies (Jani)

Cc: stable@vger.kernel.org
Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Fixes: 5448a00d3f06 ("drm/i915: Don't use staged config in check_digital_port_conflicts()")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449764551-12466-1-git-send-email-ville.syrjala@linux.intel.com
(cherry picked from commit 0bff4858653312a10c83709e0009c3adb87e6f1e)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index beb0374a19f199d23c73116dcfcd08c3d500dde0..32cf973469785cb916eb3c2bdd125a741efb5e4c 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12123,18 +12123,22 @@ static void intel_dump_pipe_config(struct intel_crtc *crtc,
 static bool check_digital_port_conflicts(struct drm_atomic_state *state)
 {
        struct drm_device *dev = state->dev;
-       struct intel_encoder *encoder;
        struct drm_connector *connector;
-       struct drm_connector_state *connector_state;
        unsigned int used_ports = 0;
-       int i;
 
        /*
         * Walk the connector list instead of the encoder
         * list to detect the problem on ddi platforms
         * where there's just one encoder per digital port.
         */
-       for_each_connector_in_state(state, connector, connector_state, i) {
+       drm_for_each_connector(connector, dev) {
+               struct drm_connector_state *connector_state;
+               struct intel_encoder *encoder;
+
+               connector_state = drm_atomic_get_existing_connector_state(state, connector);
+               if (!connector_state)
+                       connector_state = connector->state;
+
                if (!connector_state->best_encoder)
                        continue;