1 | /* SPDX-License-Identifier: MIT */ |
2 | /* |
3 | * Copyright © 2023 Intel Corporation |
4 | */ |
5 | |
6 | #ifndef __DRM_ELD_H__ |
7 | #define __DRM_ELD_H__ |
8 | |
9 | #include <linux/types.h> |
10 | |
11 | struct cea_sad; |
12 | |
13 | /* ELD Header Block */ |
14 | #define 4 |
15 | |
16 | #define DRM_ELD_VER 0 |
17 | # define DRM_ELD_VER_SHIFT 3 |
18 | # 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 4 |
26 | # define DRM_ELD_CEA_EDID_VER_SHIFT 5 |
27 | # 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 0 |
33 | # define DRM_ELD_MNL_MASK (0x1f << 0) |
34 | |
35 | #define DRM_ELD_SAD_COUNT_CONN_TYPE 5 |
36 | # define DRM_ELD_SAD_COUNT_SHIFT 4 |
37 | # define DRM_ELD_SAD_COUNT_MASK (0xf << 4) |
38 | # define DRM_ELD_CONN_TYPE_SHIFT 2 |
39 | # 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 7 |
49 | # define DRM_ELD_SPEAKER_MASK 0x7f |
50 | # 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 8 |
60 | |
61 | #define DRM_ELD_MANUFACTURER_NAME0 16 |
62 | #define DRM_ELD_MANUFACTURER_NAME1 17 |
63 | |
64 | #define DRM_ELD_PRODUCT_CODE0 18 |
65 | #define DRM_ELD_PRODUCT_CODE1 19 |
66 | |
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 set |
74 | */ |
75 | static 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 | |
80 | int drm_eld_sad_get(const u8 *eld, int sad_index, struct cea_sad *cta_sad); |
81 | int 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 set |
86 | */ |
87 | static 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 set |
105 | */ |
106 | static 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 bytes |
114 | * @eld: pointer to an eld memory structure with mnl and sad_count set |
115 | * |
116 | * This is a helper for determining the payload size of the baseline block, in |
117 | * bytes, for e.g. setting the Baseline_ELD_Len field in the ELD header block. |
118 | */ |
119 | static 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 bytes |
127 | * @eld: pointer to a complete eld memory structure |
128 | * |
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 after |
131 | * drm_eld_size() bytes of header and baseline block. |
132 | * |
133 | * The returned value is guaranteed to be a multiple of 4. |
134 | */ |
135 | static 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 allocation |
142 | * @eld: pointer to an ELD memory structure |
143 | * |
144 | * The returned value is the speakers mask. User has to use %DRM_ELD_SPEAKER |
145 | * field definitions to identify speakers. |
146 | */ |
147 | static 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 connected |
154 | * @eld: pointer to an ELD memory structure |
155 | * |
156 | * The caller need to use %DRM_ELD_CONN_TYPE_HDMI or %DRM_ELD_CONN_TYPE_DP to |
157 | * identify the display type connected. |
158 | */ |
159 | static 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 | |