diff options
Diffstat (limited to 'drivers/gpu/drm/rcar-du/rcar_du_crtc.c')
| -rw-r--r-- | drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index 79021d7aa3ce..90dacab67be5 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -735,10 +735,22 @@ enum drm_mode_status rcar_du_crtc_mode_valid(struct drm_crtc *crtc, struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc); struct rcar_du_device *rcdu = rcrtc->group->dev; bool interlaced = mode->flags & DRM_MODE_FLAG_INTERLACE; + unsigned int vbp; if (interlaced && !rcar_du_has(rcdu, RCAR_DU_FEATURE_INTERLACED)) return MODE_NO_INTERLACE; + /* + * The hardware requires a minimum combined horizontal sync and back + * porch of 20 pixels and a minimum vertical back porch of 3 lines. + */ + if (mode->htotal - mode->hsync_start < 20) + return MODE_HBLANK_NARROW; + + vbp = (mode->vtotal - mode->vsync_end) / (interlaced ? 2 : 1); + if (vbp < 3) + return MODE_VBLANK_NARROW; + return MODE_OK; } |