drm: Set crc->opened to false before setting crc source to NULL.

to terminate the while-loop in drm_dp_aux_crc_work when
drm_dp_start/stop_crc are called in the hook to set crc source.

v3: set crc->opened to false without checking (Nick)
v2: Move spin_lock around entire crc->opened use (Daniel)

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: Nick Kazlauskas <Nicholas.Kazlauskas@amd.com>
Signed-off-by: Dingchen Zhang <dingchen.zhang@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190726173743.11641-1-dingchen.zhang@amd.com

diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c
index 2ece2957da1aff26eb48b8bbd0cd8c57775d08cc..e22b812c4b802c0e6610498b36aa30bf99efb54b 100644 (file)
--- a/drivers/gpu/drm/drm_debugfs_crc.c
+++ b/drivers/gpu/drm/drm_debugfs_crc.c
@@ -258,6 +258,11 @@ static int crtc_crc_release(struct inode *inode, struct file *filep)
        struct drm_crtc *crtc = filep->f_inode->i_private;
        struct drm_crtc_crc *crc = &crtc->crc;
 
+       /* terminate the infinite while loop if 'drm_dp_aux_crc_work' running */
+       spin_lock_irq(&crc->lock);
+       crc->opened = false;
+       spin_unlock_irq(&crc->lock);
+
        crtc->funcs->set_crc_source(crtc, NULL);
 
        spin_lock_irq(&crc->lock);