[PATCH] drm/vc4: hdmi: Allow DBLCLK modes even if horz timing is odd.

[Maxime Ripard]

From: Dave Stevenson <dave.stevenson at raspberrypi.com>

The 2711 pixel valve can't produce odd horizontal timings, and
checks were added to vc4_hdmi_encoder_atomic_check and
vc4_hdmi_encoder_mode_valid to filter out/block selection of
such modes.

Modes with DRM_MODE_FLAG_DBLCLK double all the horizontal timing
values before programming them into the PV. The PV values,
therefore, can not be odd, and so the modes can be supported.

Amend the filtering appropriately.

Fixes: 57fb32e632be ("drm/vc4: hdmi: Block odd horizontal timings")
Signed-off-by: Dave Stevenson <dave.stevenson at raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime at cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 0ee446df50a0..92b1530aa17b 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -1269,6 +1269,7 @@ static int vc4_hdmi_encoder_atomic_check(struct drm_encoder *encoder,
 	unsigned long long tmds_rate;
 
 	if (vc4_hdmi->variant->unsupported_odd_h_timings &&
+	    !(mode->flags & DRM_MODE_FLAG_DBLCLK) &&
 	    ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
 	     (mode->hsync_end % 2) || (mode->htotal % 2)))
 		return -EINVAL;
@@ -1316,6 +1317,7 @@ vc4_hdmi_encoder_mode_valid(struct drm_encoder *encoder,
 	struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
 
 	if (vc4_hdmi->variant->unsupported_odd_h_timings &&
+	    !(mode->flags & DRM_MODE_FLAG_DBLCLK) &&
 	    ((mode->hdisplay % 2) || (mode->hsync_start % 2) ||
 	     (mode->hsync_end % 2) || (mode->htotal % 2)))
 		return MODE_H_ILLEGAL;
-- 
2.34.1