target/linux/mediatek/patches-5.4/0350-mtd-parsers-trx-Allow-to-specify-trx-magic-in-DT.patch

   1 From 0600e3d81628002a5cd80cf83ee454851b0063c0 Mon Sep 17 00:00:00 2001
   2 From: Hauke Mehrtens <hauke@hauke-m.de>
   3 Date: Sun, 7 Mar 2021 18:19:26 +0100
   4 Subject: mtd: parsers: trx: Allow to specify brcm,trx-magic in DT
   5
   6 Buffalo uses a different TRX magic for every device, to be able to use
   7 this trx parser, make it possible to specify the TRX magic in device
   8 tree. If no TRX magic is specified in device tree, the standard value
   9 will be used. This value should only be specified if a vendor chooses to
  10 use a non standard TRX magic.
  11
  12 Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
  13 ---
  14  .../bindings/mtd/partitions/brcm,trx.txt      |  5 +++++
  15  drivers/mtd/parsers/parser_trx.c              | 21 ++++++++++++++++++-
  16  2 files changed, 25 insertions(+), 1 deletion(-)
  17
  18 --- a/Documentation/devicetree/bindings/mtd/partitions/brcm,trx.txt
  19 +++ b/Documentation/devicetree/bindings/mtd/partitions/brcm,trx.txt
  20 @@ -28,6 +28,11 @@ detected by a software parsing TRX heade
  21  Required properties:
  22  - compatible : (required) must be "brcm,trx"
  23
  24 +Optional properties:
  25 +
  26 +- brcm,trx-magic: TRX magic, if it is different from the default magic
  27 +            0x30524448 as a u32.
  28 +
  29  Example:
  30
  31  flash@0 {
  32 --- a/drivers/mtd/parsers/parser_trx.c
  33 +++ b/drivers/mtd/parsers/parser_trx.c
  34 @@ -74,6 +74,24 @@ out_default:
  35         return "rootfs";
  36  }
  37
  38 +static uint32_t parser_trx_get_magic(struct mtd_info *mtd)
  39 +{
  40 +       uint32_t trx_magic = TRX_MAGIC;
  41 +       struct device_node *np;
  42 +       int err;
  43 +
  44 +       np = mtd_get_of_node(mtd);
  45 +       if (!np)
  46 +               return trx_magic;
  47 +
  48 +       /* Get different magic from device tree if specified */
  49 +       err = of_property_read_u32(np, "brcm,trx-magic", &trx_magic);
  50 +       if (err != 0 && err != -EINVAL)
  51 +               pr_err("failed to parse \"brcm,trx-magic\" DT attribute, use default: %d\n", err);
  52 +
  53 +       return trx_magic;
  54 +}
  55 +
  56  static int parser_trx_parse(struct mtd_info *mtd,
  57                             const struct mtd_partition **pparts,
  58                             struct mtd_part_parser_data *data)
  59 @@ -83,6 +101,7 @@ static int parser_trx_parse(struct mtd_i
  60         struct trx_header trx;
  61         size_t bytes_read;
  62         uint8_t curr_part = 0, i = 0;
  63 +       uint32_t trx_magic = parser_trx_get_magic(mtd);
  64         int err;
  65
  66         parts = kcalloc(TRX_PARSER_MAX_PARTS, sizeof(struct mtd_partition),
  67 @@ -97,7 +116,7 @@ static int parser_trx_parse(struct mtd_i
  68                 return err;
  69         }
  70
  71 -       if (trx.magic != TRX_MAGIC) {
  72 +       if (trx.magic != trx_magic) {
  73                 kfree(parts);
  74                 return -ENOENT;
  75         }