Commit 8038e09b authored Jul 06, 2017 by Maarten Lankhorst

drm/crc: Only open CRC on atomic drivers when the CRTC is active.



Commit e8fa5671 ("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 <maarten.lankhorst@linux.intel.com>
Fixes: e8fa5671 ("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 <daniel.vetter@ffwll.ch>

parent eb42ea6d

drivers/gpu/drm/drm_debugfs_crc.c

+13 −0

Original line number	Diff line number	Diff line
		@@ -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;