queue-4.14/media-cec-make-cec_get_edid_spa_location-an-inline-f.patch

   1 From 9853c7e97d70f17fe1d77f52c7a69757701aa780 Mon Sep 17 00:00:00 2001
   2 From: Hans Verkuil <hans.verkuil@cisco.com>
   3 Date: Thu, 13 Sep 2018 03:25:59 -0400
   4 Subject: media: cec: make cec_get_edid_spa_location() an inline function
   5
   6 [ Upstream commit b915bf575d5b7774d0f22d57d6c143e07dcaade2 ]
   7
   8 This function is needed by both V4L2 and CEC, so move this to
   9 cec.h as a static inline since there are no obvious shared
  10 modules between the two subsystems.
  11
  12 This patch, together with the following ones, fixes a
  13 dependency bug: if CEC_CORE is disabled, then building adv7604
  14 (and other HDMI receivers) will fail because an essential
  15 function is now stubbed out.
  16
  17 Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
  18 Cc: <stable@vger.kernel.org>      # for v4.17 and up
  19 Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
  20 Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
  21 ---
  22  drivers/media/cec/cec-edid.c | 60 -------------------------------
  23  include/media/cec.h          | 70 ++++++++++++++++++++++++++++++++++++
  24  2 files changed, 70 insertions(+), 60 deletions(-)
  25
  26 diff --git a/drivers/media/cec/cec-edid.c b/drivers/media/cec/cec-edid.c
  27 index 38e3fec6152b5..19a31d4c86035 100644
  28 --- a/drivers/media/cec/cec-edid.c
  29 +++ b/drivers/media/cec/cec-edid.c
  30 @@ -22,66 +22,6 @@
  31  #include <linux/types.h>
  32  #include <media/cec.h>
  33
  34 -/*
  35 - * This EDID is expected to be a CEA-861 compliant, which means that there are
  36 - * at least two blocks and one or more of the extensions blocks are CEA-861
  37 - * blocks.
  38 - *
  39 - * The returned location is guaranteed to be < size - 1.
  40 - */
  41 -static unsigned int cec_get_edid_spa_location(const u8 *edid, unsigned int size)
  42 -{
  43 -       unsigned int blocks = size / 128;
  44 -       unsigned int block;
  45 -       u8 d;
  46 -
  47 -       /* Sanity check: at least 2 blocks and a multiple of the block size */
  48 -       if (blocks < 2 || size % 128)
  49 -               return 0;
  50 -
  51 -       /*
  52 -        * If there are fewer extension blocks than the size, then update
  53 -        * 'blocks'. It is allowed to have more extension blocks than the size,
  54 -        * since some hardware can only read e.g. 256 bytes of the EDID, even
  55 -        * though more blocks are present. The first CEA-861 extension block
  56 -        * should normally be in block 1 anyway.
  57 -        */
  58 -       if (edid[0x7e] + 1 < blocks)
  59 -               blocks = edid[0x7e] + 1;
  60 -
  61 -       for (block = 1; block < blocks; block++) {
  62 -               unsigned int offset = block * 128;
  63 -
  64 -               /* Skip any non-CEA-861 extension blocks */
  65 -               if (edid[offset] != 0x02 || edid[offset + 1] != 0x03)
  66 -                       continue;
  67 -
  68 -               /* search Vendor Specific Data Block (tag 3) */
  69 -               d = edid[offset + 2] & 0x7f;
  70 -               /* Check if there are Data Blocks */
  71 -               if (d <= 4)
  72 -                       continue;
  73 -               if (d > 4) {
  74 -                       unsigned int i = offset + 4;
  75 -                       unsigned int end = offset + d;
  76 -
  77 -                       /* Note: 'end' is always < 'size' */
  78 -                       do {
  79 -                               u8 tag = edid[i] >> 5;
  80 -                               u8 len = edid[i] & 0x1f;
  81 -
  82 -                               if (tag == 3 && len >= 5 && i + len <= end &&
  83 -                                   edid[i + 1] == 0x03 &&
  84 -                                   edid[i + 2] == 0x0c &&
  85 -                                   edid[i + 3] == 0x00)
  86 -                                       return i + 4;
  87 -                               i += len + 1;
  88 -                       } while (i < end);
  89 -               }
  90 -       }
  91 -       return 0;
  92 -}
  93 -
  94  u16 cec_get_edid_phys_addr(const u8 *edid, unsigned int size,
  95                            unsigned int *offset)
  96  {
  97 diff --git a/include/media/cec.h b/include/media/cec.h
  98 index df6b3bd312849..b7339cc6fd3d6 100644
  99 --- a/include/media/cec.h
 100 +++ b/include/media/cec.h
 101 @@ -435,4 +435,74 @@ static inline void cec_phys_addr_invalidate(struct cec_adapter *adap)
 102         cec_s_phys_addr(adap, CEC_PHYS_ADDR_INVALID, false);
 103  }
 104
 105 +/**
 106 + * cec_get_edid_spa_location() - find location of the Source Physical Address
 107 + *
 108 + * @edid: the EDID
 109 + * @size: the size of the EDID
 110 + *
 111 + * This EDID is expected to be a CEA-861 compliant, which means that there are
 112 + * at least two blocks and one or more of the extensions blocks are CEA-861
 113 + * blocks.
 114 + *
 115 + * The returned location is guaranteed to be <= size-2.
 116 + *
 117 + * This is an inline function since it is used by both CEC and V4L2.
 118 + * Ideally this would go in a module shared by both, but it is overkill to do
 119 + * that for just a single function.
 120 + */
 121 +static inline unsigned int cec_get_edid_spa_location(const u8 *edid,
 122 +                                                    unsigned int size)
 123 +{
 124 +       unsigned int blocks = size / 128;
 125 +       unsigned int block;
 126 +       u8 d;
 127 +
 128 +       /* Sanity check: at least 2 blocks and a multiple of the block size */
 129 +       if (blocks < 2 || size % 128)
 130 +               return 0;
 131 +
 132 +       /*
 133 +        * If there are fewer extension blocks than the size, then update
 134 +        * 'blocks'. It is allowed to have more extension blocks than the size,
 135 +        * since some hardware can only read e.g. 256 bytes of the EDID, even
 136 +        * though more blocks are present. The first CEA-861 extension block
 137 +        * should normally be in block 1 anyway.
 138 +        */
 139 +       if (edid[0x7e] + 1 < blocks)
 140 +               blocks = edid[0x7e] + 1;
 141 +
 142 +       for (block = 1; block < blocks; block++) {
 143 +               unsigned int offset = block * 128;
 144 +
 145 +               /* Skip any non-CEA-861 extension blocks */
 146 +               if (edid[offset] != 0x02 || edid[offset + 1] != 0x03)
 147 +                       continue;
 148 +
 149 +               /* search Vendor Specific Data Block (tag 3) */
 150 +               d = edid[offset + 2] & 0x7f;
 151 +               /* Check if there are Data Blocks */
 152 +               if (d <= 4)
 153 +                       continue;
 154 +               if (d > 4) {
 155 +                       unsigned int i = offset + 4;
 156 +                       unsigned int end = offset + d;
 157 +
 158 +                       /* Note: 'end' is always < 'size' */
 159 +                       do {
 160 +                               u8 tag = edid[i] >> 5;
 161 +                               u8 len = edid[i] & 0x1f;
 162 +
 163 +                               if (tag == 3 && len >= 5 && i + len <= end &&
 164 +                                   edid[i + 1] == 0x03 &&
 165 +                                   edid[i + 2] == 0x0c &&
 166 +                                   edid[i + 3] == 0x00)
 167 +                                       return i + 4;
 168 +                               i += len + 1;
 169 +                       } while (i < end);
 170 +               }
 171 +       }
 172 +       return 0;
 173 +}
 174 +
 175  #endif /* _MEDIA_CEC_H */
 176 --
 177 2.20.1
 178