drm/i915: reject modes the LPT FDI receiver can't handle
More specifically, the LPT FDI RX only supports 8bpc and a maximum of
2 lanes, so anything above that won't work and should be rejected.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 5c77743..3084d01 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -198,6 +198,11 @@
if (mode->clock > max_clock)
return MODE_CLOCK_HIGH;
+ /* The FDI receiver on LPT only supports 8bpc and only has 2 lanes. */
+ if (HAS_PCH_LPT(dev) &&
+ (ironlake_get_lanes_required(mode->clock, 270000, 24) > 2))
+ return MODE_CLOCK_HIGH;
+
return MODE_OK;
}