From 8038e09be5a3ac061118bd80c7a505829920b50f Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Thu, 6 Jul 2017 15:03:15 +0200 Subject: [PATCH] drm/crc: Only open CRC on atomic drivers when the CRTC is active. Commit e8fa5671183c ("drm: crc: Wait for a frame before returning from open()") adds a wait for CRC frame, but with the CRTC off this will never be generated. For atomic drivers we know if a CRTC is active through crtc_state->active, so when inactive reject the open with -EIO. Just like with the previous patch changing debugfs opening semantics, this patch has been tested against igt. Signed-off-by: Maarten Lankhorst Fixes: e8fa5671183c ("drm: crc: Wait for a frame before returning from open()") Testcase: debugfs_test.read_all_entries Link: http://patchwork.freedesktop.org/patch/msgid/15f9d300-65d3-63aa-00e3-e83f5e4d5a7a@linux.intel.com Reviewed-by: Daniel Vetter --- drivers/gpu/drm/drm_debugfs_crc.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c index d0ea4627a093..f9e26dda56d6 100644 --- a/drivers/gpu/drm/drm_debugfs_crc.c +++ b/drivers/gpu/drm/drm_debugfs_crc.c @@ -154,6 +154,19 @@ static int crtc_crc_open(struct inode *inode, struct file *filep) size_t values_cnt; int ret = 0; + if (drm_drv_uses_atomic_modeset(crtc->dev)) { + ret = drm_modeset_lock_interruptible(&crtc->mutex, NULL); + if (ret) + return ret; + + if (!crtc->state->active) + ret = -EIO; + drm_modeset_unlock(&crtc->mutex); + + if (ret) + return ret; + } + spin_lock_irq(&crc->lock); if (!crc->opened) crc->opened = true; -- 2.20.1