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1/* SPDX-License-Identifier: MIT */2/*3 * Copyright © 2023 Intel Corporation4 */5 6#ifndef __DRM_ELD_H__7#define __DRM_ELD_H__8 9#include <linux/types.h>10 11struct cea_sad;12 13/* ELD Header Block */14#define DRM_ELD_HEADER_BLOCK_SIZE 415 16#define DRM_ELD_VER 017# define DRM_ELD_VER_SHIFT 318# define DRM_ELD_VER_MASK (0x1f << 3)19# define DRM_ELD_VER_CEA861D (2 << 3) /* supports 861D or below */20# define DRM_ELD_VER_CANNED (0x1f << 3)21 22#define DRM_ELD_BASELINE_ELD_LEN 2 /* in dwords! */23 24/* ELD Baseline Block for ELD_Ver == 2 */25#define DRM_ELD_CEA_EDID_VER_MNL 426# define DRM_ELD_CEA_EDID_VER_SHIFT 527# define DRM_ELD_CEA_EDID_VER_MASK (7 << 5)28# define DRM_ELD_CEA_EDID_VER_NONE (0 << 5)29# define DRM_ELD_CEA_EDID_VER_CEA861 (1 << 5)30# define DRM_ELD_CEA_EDID_VER_CEA861A (2 << 5)31# define DRM_ELD_CEA_EDID_VER_CEA861BCD (3 << 5)32# define DRM_ELD_MNL_SHIFT 033# define DRM_ELD_MNL_MASK (0x1f << 0)34 35#define DRM_ELD_SAD_COUNT_CONN_TYPE 536# define DRM_ELD_SAD_COUNT_SHIFT 437# define DRM_ELD_SAD_COUNT_MASK (0xf << 4)38# define DRM_ELD_CONN_TYPE_SHIFT 239# define DRM_ELD_CONN_TYPE_MASK (3 << 2)40# define DRM_ELD_CONN_TYPE_HDMI (0 << 2)41# define DRM_ELD_CONN_TYPE_DP (1 << 2)42# define DRM_ELD_SUPPORTS_AI (1 << 1)43# define DRM_ELD_SUPPORTS_HDCP (1 << 0)44 45#define DRM_ELD_AUD_SYNCH_DELAY 6 /* in units of 2 ms */46# define DRM_ELD_AUD_SYNCH_DELAY_MAX 0xfa /* 500 ms */47 48#define DRM_ELD_SPEAKER 749# define DRM_ELD_SPEAKER_MASK 0x7f50# define DRM_ELD_SPEAKER_RLRC (1 << 6)51# define DRM_ELD_SPEAKER_FLRC (1 << 5)52# define DRM_ELD_SPEAKER_RC (1 << 4)53# define DRM_ELD_SPEAKER_RLR (1 << 3)54# define DRM_ELD_SPEAKER_FC (1 << 2)55# define DRM_ELD_SPEAKER_LFE (1 << 1)56# define DRM_ELD_SPEAKER_FLR (1 << 0)57 58#define DRM_ELD_PORT_ID 8 /* offsets 8..15 inclusive */59# define DRM_ELD_PORT_ID_LEN 860 61#define DRM_ELD_MANUFACTURER_NAME0 1662#define DRM_ELD_MANUFACTURER_NAME1 1763 64#define DRM_ELD_PRODUCT_CODE0 1865#define DRM_ELD_PRODUCT_CODE1 1966 67#define DRM_ELD_MONITOR_NAME_STRING 20 /* offsets 20..(20+mnl-1) inclusive */68 69#define DRM_ELD_CEA_SAD(mnl, sad) (20 + (mnl) + 3 * (sad))70 71/**72 * drm_eld_mnl - Get ELD monitor name length in bytes.73 * @eld: pointer to an eld memory structure with mnl set74 */75static inline int drm_eld_mnl(const u8 *eld)76{77 return (eld[DRM_ELD_CEA_EDID_VER_MNL] & DRM_ELD_MNL_MASK) >> DRM_ELD_MNL_SHIFT;78}79 80int drm_eld_sad_get(const u8 *eld, int sad_index, struct cea_sad *cta_sad);81int drm_eld_sad_set(u8 *eld, int sad_index, const struct cea_sad *cta_sad);82 83/**84 * drm_eld_sad - Get ELD SAD structures.85 * @eld: pointer to an eld memory structure with sad_count set86 */87static inline const u8 *drm_eld_sad(const u8 *eld)88{89 unsigned int ver, mnl;90 91 ver = (eld[DRM_ELD_VER] & DRM_ELD_VER_MASK) >> DRM_ELD_VER_SHIFT;92 if (ver != 2 && ver != 31)93 return NULL;94 95 mnl = drm_eld_mnl(eld);96 if (mnl > 16)97 return NULL;98 99 return eld + DRM_ELD_CEA_SAD(mnl, 0);100}101 102/**103 * drm_eld_sad_count - Get ELD SAD count.104 * @eld: pointer to an eld memory structure with sad_count set105 */106static inline int drm_eld_sad_count(const u8 *eld)107{108 return (eld[DRM_ELD_SAD_COUNT_CONN_TYPE] & DRM_ELD_SAD_COUNT_MASK) >>109 DRM_ELD_SAD_COUNT_SHIFT;110}111 112/**113 * drm_eld_calc_baseline_block_size - Calculate baseline block size in bytes114 * @eld: pointer to an eld memory structure with mnl and sad_count set115 *116 * This is a helper for determining the payload size of the baseline block, in117 * bytes, for e.g. setting the Baseline_ELD_Len field in the ELD header block.118 */119static inline int drm_eld_calc_baseline_block_size(const u8 *eld)120{121 return DRM_ELD_MONITOR_NAME_STRING - DRM_ELD_HEADER_BLOCK_SIZE +122 drm_eld_mnl(eld) + drm_eld_sad_count(eld) * 3;123}124 125/**126 * drm_eld_size - Get ELD size in bytes127 * @eld: pointer to a complete eld memory structure128 *129 * The returned value does not include the vendor block. It's vendor specific,130 * and comprises of the remaining bytes in the ELD memory buffer after131 * drm_eld_size() bytes of header and baseline block.132 *133 * The returned value is guaranteed to be a multiple of 4.134 */135static inline int drm_eld_size(const u8 *eld)136{137 return DRM_ELD_HEADER_BLOCK_SIZE + eld[DRM_ELD_BASELINE_ELD_LEN] * 4;138}139 140/**141 * drm_eld_get_spk_alloc - Get speaker allocation142 * @eld: pointer to an ELD memory structure143 *144 * The returned value is the speakers mask. User has to use %DRM_ELD_SPEAKER145 * field definitions to identify speakers.146 */147static inline u8 drm_eld_get_spk_alloc(const u8 *eld)148{149 return eld[DRM_ELD_SPEAKER] & DRM_ELD_SPEAKER_MASK;150}151 152/**153 * drm_eld_get_conn_type - Get device type hdmi/dp connected154 * @eld: pointer to an ELD memory structure155 *156 * The caller need to use %DRM_ELD_CONN_TYPE_HDMI or %DRM_ELD_CONN_TYPE_DP to157 * identify the display type connected.158 */159static inline u8 drm_eld_get_conn_type(const u8 *eld)160{161 return eld[DRM_ELD_SAD_COUNT_CONN_TYPE] & DRM_ELD_CONN_TYPE_MASK;162}163 164#endif /* __DRM_ELD_H__ */165