From: Michel Dänzer <michel.daenzer@xxxxxxx> Fixes the vblank interrupt being disabled when it should be on, which can cause at least the following symptoms: * Hangs when running 'xset dpms force off' in a GNOME session with gnome-shell using DRI2. * RandR 1.4 slave outputs freezing with garbage displayed using xf86-video-ati 7.8.0 or newer. NOTE: This patch only applies to 4.5.y or older kernels. With newer kernels, this problem cannot happen because the driver now uses drm_crtc_vblank_on/off instead of drm_vblank_pre/post_modeset. I consider this patch safer for older kernels than backporting the API change, because drm_crtc_vblank_on/off had various issues in older kernels, and I'm not sure all fixes for those have been backported to all stable branches where this patch could be applied. Reported-and-Tested-by: Max Staudt <mstaudt at suse.de> Signed-off-by: Michel Dänzer <michel.daenzer at amd.com> --- drivers/gpu/drm/radeon/atombios_crtc.c | 2 ++ drivers/gpu/drm/radeon/radeon_legacy_crtc.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index dac78ad..115b4a4 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -275,6 +275,8 @@ void atombios_crtc_dpms(struct drm_crtc *crtc, int mode) atombios_enable_crtc_memreq(crtc, ATOM_ENABLE); atombios_blank_crtc(crtc, ATOM_DISABLE); drm_vblank_post_modeset(dev, radeon_crtc->crtc_id); + /* Make sure vblank interrupt is still enabled if needed */ + radeon_irq_set(rdev); radeon_crtc_load_lut(crtc); break; case DRM_MODE_DPMS_STANDBY: diff --git a/drivers/gpu/drm/radeon/radeon_legacy_crtc.c b/drivers/gpu/drm/radeon/radeon_legacy_crtc.c index 678b438..89f22bd 100644 --- a/drivers/gpu/drm/radeon/radeon_legacy_crtc.c +++ b/drivers/gpu/drm/radeon/radeon_legacy_crtc.c @@ -331,6 +331,8 @@ static void radeon_crtc_dpms(struct drm_crtc *crtc, int mode) WREG32_P(RADEON_CRTC_EXT_CNTL, crtc_ext_cntl, ~(mask | crtc_ext_cntl)); } drm_vblank_post_modeset(dev, radeon_crtc->crtc_id); + /* Make sure vblank interrupt is still enabled if needed */ + radeon_irq_set(rdev); radeon_crtc_load_lut(crtc); break; case DRM_MODE_DPMS_STANDBY: -- 2.10.2