kernel/drivers/video/fbdev/omap2/dss/hdmi_common.c

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