drm/bridge: tc358767: reject modes which require too much BW

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 <tomi.valkeinen@ti.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190103115954.12785-6-tomi.valkeinen@ti.com
This commit is contained in:
Tomi Valkeinen 2019-01-03 13:59:52 +02:00 committed by Andrzej Hajda
parent 9a63bd6fe1
commit 51b9e62eb6

View File

@ -1114,10 +1114,20 @@ static bool tc_bridge_mode_fixup(struct drm_bridge *bridge,
static enum drm_mode_status 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;
}