diff options
Diffstat (limited to 'include/drm/drm_dp_helper.h')
| -rw-r--r-- | include/drm/drm_dp_helper.h | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 20eb5ca28594..b17476a6909c 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -1081,4 +1081,55 @@ 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). + * @quirks: Quirks; use drm_dp_has_quirk() to query for the quirks. + */ +struct drm_dp_desc { + struct drm_dp_dpcd_ident ident; + u32 quirks; +}; + +int drm_dp_read_desc(struct drm_dp_aux *aux, struct drm_dp_desc *desc, + bool is_branch); + +/** + * enum drm_dp_quirk - Display Port sink/branch device specific quirks + * + * Display Port sink and branch devices in the wild have a variety of bugs, try + * to collect them here. The quirks are shared, but it's up to the drivers to + * implement workarounds for them. + */ +enum drm_dp_quirk { + /** + * @DP_DPCD_QUIRK_LIMITED_M_N: + * + * The device requires main link attributes Mvid and Nvid to be limited + * to 16 bits. + */ + DP_DPCD_QUIRK_LIMITED_M_N, +}; + +/** + * drm_dp_has_quirk() - does the DP device have a specific quirk + * @desc: Device decriptor filled by drm_dp_read_desc() + * @quirk: Quirk to query for + * + * Return true if DP device identified by @desc has @quirk. + */ +static inline bool +drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk) +{ + return desc->quirks & BIT(quirk); +} + #endif /* _DRM_DP_HELPER_H_ */ |