diff options
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 16 | ||||
| -rw-r--r-- | include/drm/drm_dp_helper.h | 3 |
2 files changed, 19 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index da6bcfe..84262ed 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -456,3 +456,19 @@ ssize_t drm_dp_dpcd_write(struct drm_dp_aux *aux, unsigned int offset, size); } EXPORT_SYMBOL(drm_dp_dpcd_write); + +/** + * drm_dp_dpcd_read_link_status() - read DPCD link status (bytes 0x202-0x207) + * @aux: DisplayPort AUX channel + * @status: buffer to store the link status in (must be at least 6 bytes) + * + * Returns the number of bytes transferred on success or a negative error + * code on failure. + */ +int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, + u8 status[DP_LINK_STATUS_SIZE]) +{ + return drm_dp_dpcd_read(aux, DP_LANE0_1_STATUS, status, + DP_LINK_STATUS_SIZE); +} +EXPORT_SYMBOL(drm_dp_dpcd_read_link_status); diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 70f18eb..a78711f 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -477,4 +477,7 @@ static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux *aux, return drm_dp_dpcd_write(aux, offset, &value, 1); } +int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, + u8 status[DP_LINK_STATUS_SIZE]); + #endif /* _DRM_DP_HELPER_H_ */ |