From 4012cf67b9f1841ad582ca094c230439d98c8a4d Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Wed, 9 Dec 2009 11:23:42 +0800 Subject: [PATCH] drm: disable all the possible outputs/crtcs before entering KMS mode commit b16d9acbdb97452d1418420e069acf7381ef10bb upstream. Sometimes we will use a crtc for integerated LVDS, which is different with that assigned by BIOS. If we want to get flicker-free transitions, then we could read out the current state for it and set our current state accordingly. But it is true that if we aren't reading current state out, we do need to turn everything off before modesetting. Otherwise the clocks can get very angry and we get things worse than a flicker at boot. In fact we also do the similar thing in UMS mode. We will disable all the possible outputs/crtcs for the first modesetting. So we disable all the possible outputs/crtcs before entering the KMS mode. Before we configure connector/encoder/crtc, the function of drm_helper_disable_unused_function can disable all the possible outputs/crtcs. Signed-off-by: Zhao Yakui Reviewed-by: Eric Anholt Reviewed-by: Rafal Milecki Signed-off-by: Dave Airlie Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_crtc_helper.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c index bbfd110a7168..afed886cb0fe 100644 --- a/drivers/gpu/drm/drm_crtc_helper.c +++ b/drivers/gpu/drm/drm_crtc_helper.c @@ -1020,6 +1020,9 @@ bool drm_helper_initial_config(struct drm_device *dev) { int count = 0; + /* disable all the possible outputs/crtcs before entering KMS mode */ + drm_helper_disable_unused_functions(dev); + drm_fb_helper_parse_command_line(dev); count = drm_helper_probe_connector_modes(dev, -- 2.39.5