recipes-kernel/most/files/0008-dim2-read-clock-speed-from-the-device-tree.patch

   1 From 839ad403a2d8081a6c15f6fc2836b01919338f3c Mon Sep 17 00:00:00 2001
   2 From: Andrey Shvetsov <andrey.shvetsov@k2l.de>
   3 Date: Mon, 12 Feb 2018 12:24:37 +0100
   4 Subject: [PATCH] staging: most: dim2: read clock speed from the device tree
   5
   6 This implements reading of the clock speed parameter from the device
   7 tree.
   8
   9 Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
  10 ---
  11  Documentation/devicetree/bindings/inic/microchip,inic-dim2.txt | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
  12  hdm-dim2/dim2_hdm.c                       | 50 +++++++++++++++++++++++++++++++++++++++++++++++++-
  13  2 files changed, 113 insertions(+), 1 deletion(-)
  14  create mode 100644 Documentation/devicetree/bindings/inic/microchip,inic-dim2.txt
  15
  16 diff --git a/hdm-dim2/dim2_hdm.c b/hdm-dim2/dim2_hdm.c
  17 index 2dba917..05e1896 100644
  18 --- a/hdm-dim2/dim2_hdm.c
  19 +++ b/hdm-dim2/dim2_hdm.c
  20 @@ -698,6 +698,42 @@ static void dma_free(struct mbo *mbo, u32 size)
  21
  22  static const struct of_device_id dim2_of_match[];
  23
  24 +static struct {
  25 +       const char *clock_speed;
  26 +       u8 clk_speed;
  27 +} clk_mt[] = {
  28 +       { "256fs", CLK_256FS },
  29 +       { "512fs", CLK_512FS },
  30 +       { "1024fs", CLK_1024FS },
  31 +       { "2048fs", CLK_2048FS },
  32 +       { "3072fs", CLK_3072FS },
  33 +       { "4096fs", CLK_4096FS },
  34 +       { "6144fs", CLK_6144FS },
  35 +       { "8192fs", CLK_8192FS },
  36 +};
  37 +
  38 +/**
  39 + * get_dim2_clk_speed - converts string to DIM2 clock speed value
  40 + *
  41 + * @clock_speed: string in the format "{NUMBER}fs"
  42 + * @val: pointer to get one of the CLK_{NUMBER}FS values
  43 + *
  44 + * By success stores one of the CLK_{NUMBER}FS in the *val and returns 0,
  45 + * otherwise returns -EINVAL.
  46 + */
  47 +static int get_dim2_clk_speed(const char *clock_speed, u8 *val)
  48 +{
  49 +       int i;
  50 +
  51 +       for (i = 0; i < ARRAY_SIZE(clk_mt); i++) {
  52 +               if (!strcmp(clock_speed, clk_mt[i].clock_speed)) {
  53 +                       *val = clk_mt[i].clk_speed;
  54 +                       return 0;
  55 +               }
  56 +       }
  57 +       return -EINVAL;
  58 +}
  59 +
  60  /*
  61   * dim2_probe - dim2 probe handler
  62   * @pdev: platform device structure
  63 @@ -708,6 +744,7 @@ static const struct of_device_id dim2_of_match[];
  64  static int dim2_probe(struct platform_device *pdev)
  65  {
  66         const struct dim2_platform_data *pdata;
  67 +       const char *clock_speed;
  68         struct dim2_hdm *dev;
  69         struct resource *res;
  70         int ret, i;
  71 @@ -725,7 +762,18 @@ static int dim2_probe(struct platform_device *pdev)
  72
  73         platform_set_drvdata(pdev, dev);
  74
  75 -       dev->clk_speed = CLK_4096FS;
  76 +       ret = of_property_read_string(pdev->dev.of_node,
  77 +                                     "microchip,clock-speed", &clock_speed);
  78 +       if (ret) {
  79 +               dev_err(&pdev->dev, "missing dt property clock-speed\n");
  80 +               return ret;
  81 +       }
  82 +
  83 +       ret = get_dim2_clk_speed(clock_speed, &dev->clk_speed);
  84 +       if (ret) {
  85 +               dev_err(&pdev->dev, "bad dt property clock-speed\n");
  86 +               return ret;
  87 +       }
  88
  89         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  90         dev->io_base = devm_ioremap_resource(&pdev->dev, res);
  91 --
  92 libgit2 0.26.0