drm/dp: add helper for reading DP sink/branch device desc from DPCD

[karo-tx-linux.git] / include / drm / drm_dp_helper.h

diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index c0bd0d7651a947bf06407d7c680dde5c377b9b26..84502da177a1681a6c7ac4b2b838e362bd24bc4d 100644 (file)
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -913,4 +913,23 @@ 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);
 
+struct drm_dp_dpcd_ident {
+       u8 oui[3];
+       u8 device_id[6];
+       u8 hw_rev;
+       u8 sw_major_rev;
+       u8 sw_minor_rev;
+} __packed;
+
+/**
+ * struct drm_dp_desc - DP branch/sink device descriptor
+ * @ident: DP device identification from DPCD 0x400 (sink) or 0x500 (branch).
+ */
+struct drm_dp_desc {
+       struct drm_dp_dpcd_ident ident;
+};
+
+int drm_dp_read_desc(struct drm_dp_aux *aux, struct drm_dp_desc *desc,
+                    bool is_branch);
+
 #endif /* _DRM_DP_HELPER_H_ */