From: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx> Post_disable was sending the D-PHY sequence to put any device into ULPS suspend mode, and then cutting power to the DSI block. The power-on reset state of the DSI block is for DSI to be in an operational state, not ULPS, so it then never sent the sequence for exiting ULPS. Any attached device that didn't have an external reset therefore remained in ULPS / standby, and didn't function. Use of ULPS isn't well specified in DRM, therefore remove entering it to avoid the above situation. Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> --- drivers/gpu/drm/vc4/vc4_dsi.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c index a7b8ffd995b0..4f3805528aa1 100644 --- a/drivers/gpu/drm/vc4/vc4_dsi.c +++ b/drivers/gpu/drm/vc4/vc4_dsi.c @@ -813,8 +813,6 @@ static void vc4_dsi_bridge_post_disable(struct drm_bridge *bridge, struct vc4_dsi *dsi = bridge_to_vc4_dsi(bridge); struct device *dev = &dsi->pdev->dev; - vc4_dsi_ulps(dsi, true); - clk_disable_unprepare(dsi->pll_phy_clock); clk_disable_unprepare(dsi->escape_clock); clk_disable_unprepare(dsi->pixel_clock); -- 2.38.1