diff options
Diffstat (limited to 'include/drm/drm_eld.h')
| -rw-r--r-- | include/drm/drm_eld.h | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/include/drm/drm_eld.h b/include/drm/drm_eld.h new file mode 100644 index 0000000000..0a88d10b28 --- /dev/null +++ b/include/drm/drm_eld.h @@ -0,0 +1,164 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Copyright © 2023 Intel Corporation + */ + +#ifndef __DRM_ELD_H__ +#define __DRM_ELD_H__ + +#include <linux/types.h> + +struct cea_sad; + +/* ELD Header Block */ +#define DRM_ELD_HEADER_BLOCK_SIZE 4 + +#define DRM_ELD_VER 0 +# define DRM_ELD_VER_SHIFT 3 +# define DRM_ELD_VER_MASK (0x1f << 3) +# define DRM_ELD_VER_CEA861D (2 << 3) /* supports 861D or below */ +# define DRM_ELD_VER_CANNED (0x1f << 3) + +#define DRM_ELD_BASELINE_ELD_LEN 2 /* in dwords! */ + +/* ELD Baseline Block for ELD_Ver == 2 */ +#define DRM_ELD_CEA_EDID_VER_MNL 4 +# define DRM_ELD_CEA_EDID_VER_SHIFT 5 +# define DRM_ELD_CEA_EDID_VER_MASK (7 << 5) +# define DRM_ELD_CEA_EDID_VER_NONE (0 << 5) +# define DRM_ELD_CEA_EDID_VER_CEA861 (1 << 5) +# define DRM_ELD_CEA_EDID_VER_CEA861A (2 << 5) +# define DRM_ELD_CEA_EDID_VER_CEA861BCD (3 << 5) +# define DRM_ELD_MNL_SHIFT 0 +# define DRM_ELD_MNL_MASK (0x1f << 0) + +#define DRM_ELD_SAD_COUNT_CONN_TYPE 5 +# define DRM_ELD_SAD_COUNT_SHIFT 4 +# define DRM_ELD_SAD_COUNT_MASK (0xf << 4) +# define DRM_ELD_CONN_TYPE_SHIFT 2 +# define DRM_ELD_CONN_TYPE_MASK (3 << 2) +# define DRM_ELD_CONN_TYPE_HDMI (0 << 2) +# define DRM_ELD_CONN_TYPE_DP (1 << 2) +# define DRM_ELD_SUPPORTS_AI (1 << 1) +# define DRM_ELD_SUPPORTS_HDCP (1 << 0) + +#define DRM_ELD_AUD_SYNCH_DELAY 6 /* in units of 2 ms */ +# define DRM_ELD_AUD_SYNCH_DELAY_MAX 0xfa /* 500 ms */ + +#define DRM_ELD_SPEAKER 7 +# define DRM_ELD_SPEAKER_MASK 0x7f +# define DRM_ELD_SPEAKER_RLRC (1 << 6) +# define DRM_ELD_SPEAKER_FLRC (1 << 5) +# define DRM_ELD_SPEAKER_RC (1 << 4) +# define DRM_ELD_SPEAKER_RLR (1 << 3) +# define DRM_ELD_SPEAKER_FC (1 << 2) +# define DRM_ELD_SPEAKER_LFE (1 << 1) +# define DRM_ELD_SPEAKER_FLR (1 << 0) + +#define DRM_ELD_PORT_ID 8 /* offsets 8..15 inclusive */ +# define DRM_ELD_PORT_ID_LEN 8 + +#define DRM_ELD_MANUFACTURER_NAME0 16 +#define DRM_ELD_MANUFACTURER_NAME1 17 + +#define DRM_ELD_PRODUCT_CODE0 18 +#define DRM_ELD_PRODUCT_CODE1 19 + +#define DRM_ELD_MONITOR_NAME_STRING 20 /* offsets 20..(20+mnl-1) inclusive */ + +#define DRM_ELD_CEA_SAD(mnl, sad) (20 + (mnl) + 3 * (sad)) + +/** + * drm_eld_mnl - Get ELD monitor name length in bytes. + * @eld: pointer to an eld memory structure with mnl set + */ +static inline int drm_eld_mnl(const u8 *eld) +{ + return (eld[DRM_ELD_CEA_EDID_VER_MNL] & DRM_ELD_MNL_MASK) >> DRM_ELD_MNL_SHIFT; +} + +int drm_eld_sad_get(const u8 *eld, int sad_index, struct cea_sad *cta_sad); +int drm_eld_sad_set(u8 *eld, int sad_index, const struct cea_sad *cta_sad); + +/** + * drm_eld_sad - Get ELD SAD structures. + * @eld: pointer to an eld memory structure with sad_count set + */ +static inline const u8 *drm_eld_sad(const u8 *eld) +{ + unsigned int ver, mnl; + + ver = (eld[DRM_ELD_VER] & DRM_ELD_VER_MASK) >> DRM_ELD_VER_SHIFT; + if (ver != 2 && ver != 31) + return NULL; + + mnl = drm_eld_mnl(eld); + if (mnl > 16) + return NULL; + + return eld + DRM_ELD_CEA_SAD(mnl, 0); +} + +/** + * drm_eld_sad_count - Get ELD SAD count. + * @eld: pointer to an eld memory structure with sad_count set + */ +static inline int drm_eld_sad_count(const u8 *eld) +{ + return (eld[DRM_ELD_SAD_COUNT_CONN_TYPE] & DRM_ELD_SAD_COUNT_MASK) >> + DRM_ELD_SAD_COUNT_SHIFT; +} + +/** + * drm_eld_calc_baseline_block_size - Calculate baseline block size in bytes + * @eld: pointer to an eld memory structure with mnl and sad_count set + * + * This is a helper for determining the payload size of the baseline block, in + * bytes, for e.g. setting the Baseline_ELD_Len field in the ELD header block. + */ +static inline int drm_eld_calc_baseline_block_size(const u8 *eld) +{ + return DRM_ELD_MONITOR_NAME_STRING - DRM_ELD_HEADER_BLOCK_SIZE + + drm_eld_mnl(eld) + drm_eld_sad_count(eld) * 3; +} + +/** + * drm_eld_size - Get ELD size in bytes + * @eld: pointer to a complete eld memory structure + * + * The returned value does not include the vendor block. It's vendor specific, + * and comprises of the remaining bytes in the ELD memory buffer after + * drm_eld_size() bytes of header and baseline block. + * + * The returned value is guaranteed to be a multiple of 4. + */ +static inline int drm_eld_size(const u8 *eld) +{ + return DRM_ELD_HEADER_BLOCK_SIZE + eld[DRM_ELD_BASELINE_ELD_LEN] * 4; +} + +/** + * drm_eld_get_spk_alloc - Get speaker allocation + * @eld: pointer to an ELD memory structure + * + * The returned value is the speakers mask. User has to use %DRM_ELD_SPEAKER + * field definitions to identify speakers. + */ +static inline u8 drm_eld_get_spk_alloc(const u8 *eld) +{ + return eld[DRM_ELD_SPEAKER] & DRM_ELD_SPEAKER_MASK; +} + +/** + * drm_eld_get_conn_type - Get device type hdmi/dp connected + * @eld: pointer to an ELD memory structure + * + * The caller need to use %DRM_ELD_CONN_TYPE_HDMI or %DRM_ELD_CONN_TYPE_DP to + * identify the display type connected. + */ +static inline u8 drm_eld_get_conn_type(const u8 *eld) +{ + return eld[DRM_ELD_SAD_COUNT_CONN_TYPE] & DRM_ELD_CONN_TYPE_MASK; +} + +#endif /* __DRM_ELD_H__ */ |