From: Tomi Valkeinen Date: Thu, 3 Jan 2019 11:59:52 +0000 (+0200) Subject: drm/bridge: tc358767: reject modes which require too much BW X-Git-Tag: v4.14.102~34 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=9a5bce69646dd7c2d2c2977d19de3a6c0e45db05;p=users%2Fjedix%2Flinux-maple.git drm/bridge: tc358767: reject modes which require too much BW [ Upstream commit 51b9e62eb6950c762162ab7eb8390990179be067 ] The current driver accepts any videomode with pclk < 154MHz. This is not correct, as with 1 lane and/or 1.62Mbps speed not all videomodes can be supported. Add code to reject modes that require more bandwidth that is available. Signed-off-by: Tomi Valkeinen Reviewed-by: Andrzej Hajda Signed-off-by: Andrzej Hajda Link: https://patchwork.freedesktop.org/patch/msgid/20190103115954.12785-6-tomi.valkeinen@ti.com Signed-off-by: Sasha Levin --- diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c index 24bb6bfa36f34..792a2548d3bb5 100644 --- a/drivers/gpu/drm/bridge/tc358767.c +++ b/drivers/gpu/drm/bridge/tc358767.c @@ -1112,10 +1112,20 @@ static bool tc_bridge_mode_fixup(struct drm_bridge *bridge, static int tc_connector_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode) { + struct tc_data *tc = connector_to_tc(connector); + u32 req, avail; + u32 bits_per_pixel = 24; + /* DPI interface clock limitation: upto 154 MHz */ if (mode->clock > 154000) return MODE_CLOCK_HIGH; + req = mode->clock * bits_per_pixel / 8; + avail = tc->link.base.num_lanes * tc->link.base.rate; + + if (req > avail) + return MODE_BAD; + return MODE_OK; }