From 7c4c55845ca40b56c9486064cc5c6d9b884d4d76 Mon Sep 17 00:00:00 2001 From: Joonyoung Shim Date: Sun, 18 Jan 2015 17:48:29 +0900 Subject: [PATCH] drm/exynos: fix warning of vblank reference count Prevented re-enabling the vblank interrupt by drm_vblank_off and drm_vblank_get from mixer_wait_for_vblank returns error after drm_vblank_off. We get below warnings without this error handling because vblank reference count is mismatched by above sequence. setting mode 1920x1080-60Hz@XR24 on connectors 16, crtc 13 [ 19.900793] ------------[ cut here ]------------ [ 19.903959] WARNING: CPU: 0 PID: 0 at drivers/gpu/drm/drm_irq.c:1072 exynos_drm_crtc_finish_pageflip+0xac/0xdc() [ 19.914076] Modules linked in: [ 19.917116] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.19.0-rc4-00040-g3d729789-dirty #46 [ 19.925342] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 19.931437] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 19.939131] [] (show_stack) from [] (dump_stack+0x84/0xc4) [ 19.946329] [] (dump_stack) from [] (warn_slowpath_common+0x80/0xb0) [ 19.954382] [] (warn_slowpath_common) from [] (warn_slowpath_null+0x1c/0x24) [ 19.963132] [] (warn_slowpath_null) from [] (exynos_drm_crtc_finish_pageflip+0xac/0xdc) [ 19.972841] [] (exynos_drm_crtc_finish_pageflip) from [] (mixer_irq_handler+0xdc/0x104) [ 19.982546] [] (mixer_irq_handler) from [] (handle_irq_event_percpu+0x78/0x134) [ 19.991555] [] (handle_irq_event_percpu) from [] (handle_irq_event+0x3c/0x5c) [ 20.000395] [] (handle_irq_event) from [] (handle_fasteoi_irq+0xe0/0x1ac) [ 20.008885] [] (handle_fasteoi_irq) from [] (generic_handle_irq+0x2c/0x3c) [ 20.017463] [] (generic_handle_irq) from [] (__handle_domain_irq+0x7c/0xec) [ 20.026128] [] (__handle_domain_irq) from [] (gic_handle_irq+0x30/0x68) [ 20.034449] [] (gic_handle_irq) from [] (__irq_svc+0x40/0x74) [ 20.041893] Exception stack(0xc06fff68 to 0xc06fffb0) [ 20.046923] ff60: 00000000 00000000 000052f6 c001b460 c06fe000 c07064e8 [ 20.055070] ff80: c04d743c c07392a2 c0739440 c06da340 ef7fca80 00000000 01000000 c06fffb0 [ 20.063212] ffa0: c000f24c c000f250 60000013 ffffffff [ 20.068245] [] (__irq_svc) from [] (arch_cpu_idle+0x38/0x3c) [ 20.075611] [] (arch_cpu_idle) from [] (cpu_startup_entry+0x108/0x16c) [ 20.083846] [] (cpu_startup_entry) from [] (start_kernel+0x3a0/0x3ac) [ 20.091980] ---[ end trace 2c76ee0500489d1b ]--- Signed-off-by: Joonyoung Shim Signed-off-by: Inki Dae --- drivers/gpu/drm/exynos/exynos_mixer.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c index 71f1688b188c..064ed6597def 100644 --- a/drivers/gpu/drm/exynos/exynos_mixer.c +++ b/drivers/gpu/drm/exynos/exynos_mixer.c @@ -1026,6 +1026,7 @@ static void mixer_win_disable(struct exynos_drm_manager *mgr, int zpos) static void mixer_wait_for_vblank(struct exynos_drm_manager *mgr) { struct mixer_context *mixer_ctx = mgr_to_mixer(mgr); + int err; mutex_lock(&mixer_ctx->mixer_mutex); if (!mixer_ctx->powered) { @@ -1034,7 +1035,11 @@ static void mixer_wait_for_vblank(struct exynos_drm_manager *mgr) } mutex_unlock(&mixer_ctx->mixer_mutex); - drm_vblank_get(mgr->crtc->dev, mixer_ctx->pipe); + err = drm_vblank_get(mgr->crtc->dev, mixer_ctx->pipe); + if (err < 0) { + DRM_DEBUG_KMS("failed to acquire vblank counter\n"); + return; + } atomic_set(&mixer_ctx->wait_vsync_event, 1); -- 2.20.1