From: Marek Vasut <marex@xxxxxxx> [ Upstream commit ebd267b2e3c25d5f93a08528b47c036569eb8744 ] Add missing pm_runtime_get_sync() into ltdc_crtc_atomic_enable() to match pm_runtime_put_sync() in ltdc_crtc_atomic_disable(), otherwise the LTDC might suspend via runtime PM, disable clock, and then fail to resume later on. The test which triggers it is roughly -- run qt5 application which uses eglfs platform and etnaviv, stop the application, sleep for 15 minutes, run the application again. This leads to a timeout waiting for vsync, because the LTDC has suspended, but did not resume. Fixes: 35ab6cfbf211 ("drm/stm: support runtime power management") Signed-off-by: Marek Vasut <marex@xxxxxxx> Cc: Yannick Fertré <yannick.fertre@xxxxxx> Cc: Philippe Cornu <philippe.cornu@xxxxxx> Cc: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx> Cc: Vincent Abriou <vincent.abriou@xxxxxx> Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx> Cc: Alexandre Torgue <alexandre.torgue@xxxxxx> To: dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Acked-by: Philippe Cornu <philippe.cornu@xxxxxx> Tested-by: Yannick Fertre <yannick.fertre@xxxxxx> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20200229221649.90813-1-marex@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/stm/ltdc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 3ab4fbf8eb0d1..51571f7246abf 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -424,9 +424,12 @@ static void ltdc_crtc_atomic_enable(struct drm_crtc *crtc, struct drm_crtc_state *old_state) { struct ltdc_device *ldev = crtc_to_ltdc(crtc); + struct drm_device *ddev = crtc->dev; DRM_DEBUG_DRIVER("\n"); + pm_runtime_get_sync(ddev->dev); + /* Sets the background color value */ reg_write(ldev->regs, LTDC_BCCR, BCCR_BCBLACK); -- 2.25.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel