1// SPDX-License-Identifier: GPL-2.0
2
3#define DSS_SUBSYS_NAME "HDMI"
4
5#include <linux/kernel.h>
6#include <linux/err.h>
7#include <linux/of.h>
8
9#include "omapdss.h"
10#include "hdmi.h"
11
12int hdmi_parse_lanes_of(struct platform_device *pdev, struct device_node *ep,
13 struct hdmi_phy_data *phy)
14{
15 struct property *prop;
16 int r, len;
17
18 prop = of_find_property(np: ep, name: "lanes", lenp: &len);
19 if (prop) {
20 u32 lanes[8];
21
22 if (len / sizeof(u32) != ARRAY_SIZE(lanes)) {
23 dev_err(&pdev->dev, "bad number of lanes\n");
24 return -EINVAL;
25 }
26
27 r = of_property_read_u32_array(np: ep, propname: "lanes", out_values: lanes,
28 ARRAY_SIZE(lanes));
29 if (r) {
30 dev_err(&pdev->dev, "failed to read lane data\n");
31 return r;
32 }
33
34 r = hdmi_phy_parse_lanes(phy, lanes);
35 if (r) {
36 dev_err(&pdev->dev, "failed to parse lane data\n");
37 return r;
38 }
39 } else {
40 static const u32 default_lanes[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
41
42 r = hdmi_phy_parse_lanes(phy, lanes: default_lanes);
43 if (WARN_ON(r)) {
44 dev_err(&pdev->dev, "failed to parse lane data\n");
45 return r;
46 }
47 }
48
49 return 0;
50}
51
52int hdmi_compute_acr(u32 pclk, u32 sample_freq, u32 *n, u32 *cts)
53{
54 u32 deep_color;
55 bool deep_color_correct = false;
56
57 if (n == NULL || cts == NULL)
58 return -EINVAL;
59
60 /* TODO: When implemented, query deep color mode here. */
61 deep_color = 100;
62
63 /*
64 * When using deep color, the default N value (as in the HDMI
65 * specification) yields to an non-integer CTS. Hence, we
66 * modify it while keeping the restrictions described in
67 * section 7.2.1 of the HDMI 1.4a specification.
68 */
69 switch (sample_freq) {
70 case 32000:
71 case 48000:
72 case 96000:
73 case 192000:
74 if (deep_color == 125)
75 if (pclk == 27027000 || pclk == 74250000)
76 deep_color_correct = true;
77 if (deep_color == 150)
78 if (pclk == 27027000)
79 deep_color_correct = true;
80 break;
81 case 44100:
82 case 88200:
83 case 176400:
84 if (deep_color == 125)
85 if (pclk == 27027000)
86 deep_color_correct = true;
87 break;
88 default:
89 return -EINVAL;
90 }
91
92 if (deep_color_correct) {
93 switch (sample_freq) {
94 case 32000:
95 *n = 8192;
96 break;
97 case 44100:
98 *n = 12544;
99 break;
100 case 48000:
101 *n = 8192;
102 break;
103 case 88200:
104 *n = 25088;
105 break;
106 case 96000:
107 *n = 16384;
108 break;
109 case 176400:
110 *n = 50176;
111 break;
112 case 192000:
113 *n = 32768;
114 break;
115 default:
116 return -EINVAL;
117 }
118 } else {
119 switch (sample_freq) {
120 case 32000:
121 *n = 4096;
122 break;
123 case 44100:
124 *n = 6272;
125 break;
126 case 48000:
127 *n = 6144;
128 break;
129 case 88200:
130 *n = 12544;
131 break;
132 case 96000:
133 *n = 12288;
134 break;
135 case 176400:
136 *n = 25088;
137 break;
138 case 192000:
139 *n = 24576;
140 break;
141 default:
142 return -EINVAL;
143 }
144 }
145 /* Calculate CTS. See HDMI 1.3a or 1.4a specifications */
146 *cts = (pclk/1000) * (*n / 128) * deep_color / (sample_freq / 10);
147
148 return 0;
149}
150

source code of linux/drivers/gpu/drm/omapdrm/dss/hdmi_common.c