drm/dp: add helpers for capture of frame CRCs

Adds helpers for starting and stopping capture of frame CRCs through the
DPCD. When capture is on, a worker waits for vblanks and retrieves the
frame CRC to put it in the queue on the CRTC that is using the
eDP connector, so it's passed to userspace.

v2: Reuse drm_crtc_wait_one_vblank
    Update locking, as drm_crtc_add_crc_entry now takes the lock

v3: Don't call wake_up_interruptible directly, that's now done in
    drm_crtc_add_crc_entry.

v4: Style fixes (Sean Paul)
    Reworked retry of CRC reads (Sean Paul)
    Flush worker after stopping CRC generationa (Sean Paul)

v5: Move back to make the retry explicitly once

v6: Set and use the drm_crtc backpointer (Sean Paul)

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303133936.14964-3-tomeu.vizoso@collabora.com
This commit is contained in:
Tomeu Vizoso
2017-03-03 14:39:34 +01:00
committed by Sean Paul
parent 4bb310fd9e
commit 79c1da7c3b
2 changed files with 133 additions and 0 deletions

View File

@@ -734,6 +734,8 @@ struct drm_dp_aux_msg {
* @dev: pointer to struct device that is the parent for this AUX channel
* @crtc: backpointer to the crtc that is currently using this AUX channel
* @hw_mutex: internal mutex used for locking transfers
* @crc_work: worker that captures CRCs for each frame
* @crc_count: counter of captured frame CRCs
* @transfer: transfers a message representing a single AUX transaction
*
* The .dev field should be set to a pointer to the device that implements
@@ -771,6 +773,8 @@ struct drm_dp_aux {
struct device *dev;
struct drm_crtc *crtc;
struct mutex hw_mutex;
struct work_struct crc_work;
u8 crc_count;
ssize_t (*transfer)(struct drm_dp_aux *aux,
struct drm_dp_aux_msg *msg);
/**
@@ -849,4 +853,7 @@ void drm_dp_aux_init(struct drm_dp_aux *aux);
int drm_dp_aux_register(struct drm_dp_aux *aux);
void drm_dp_aux_unregister(struct drm_dp_aux *aux);
int drm_dp_start_crc(struct drm_dp_aux *aux, struct drm_crtc *crtc);
int drm_dp_stop_crc(struct drm_dp_aux *aux);
#endif /* _DRM_DP_HELPER_H_ */