target/linux/bcm27xx/patches-5.15/950-0722-media-i2c-Add-support-for-19.2MHz-clock-to-ov7251.patch

   1 From 16af9ae925fdb05960f644b6cc84098af8aa3956 Mon Sep 17 00:00:00 2001
   2 From: Daniel Scally <djrscally@gmail.com>
   3 Date: Tue, 15 Feb 2022 23:07:33 +0000
   4 Subject: [PATCH] media: i2c: Add support for 19.2MHz clock to ov7251
   5
   6 The OV7251 sensor is used as the IR camera sensor on the Microsoft
   7 Surface line of tablets; this provides a 19.2MHz external clock. Add
   8 the ability to support that rate to the driver by defining a new set
   9 of PLL configs. Extend the clock handling in .probe() to check for
  10 either supported frequency.
  11
  12 Signed-off-by: Daniel Scally <djrscally@gmail.com>
  13 ---
  14  drivers/media/i2c/ov7251.c | 61 ++++++++++++++++++++++++++++----------
  15  1 file changed, 45 insertions(+), 16 deletions(-)
  16
  17 --- a/drivers/media/i2c/ov7251.c
  18 +++ b/drivers/media/i2c/ov7251.c
  19 @@ -134,10 +134,19 @@ static inline struct ov7251 *to_ov7251(s
  20  }
  21
  22  enum xclk_rate {
  23 +       OV7251_19_2_MHZ,
  24         OV7251_24_MHZ,
  25         OV7251_NUM_SUPPORTED_RATES
  26  };
  27
  28 +static const struct ov7251_pll1_config ov7251_pll1_config_19_2_mhz = {
  29 +       .pre_div = 0x03,
  30 +       .mult = 0x4b,
  31 +       .div = 0x01,
  32 +       .pix_div = 0x0a,
  33 +       .mipi_div = 0x05
  34 +};
  35 +
  36  static const struct ov7251_pll1_config ov7251_pll1_config_24_mhz = {
  37         .pre_div = 0x03,
  38         .mult = 0x64,
  39 @@ -146,6 +155,14 @@ static const struct ov7251_pll1_config o
  40         .mipi_div = 0x05
  41  };
  42
  43 +static const struct ov7251_pll2_config ov7251_pll2_config_19_2_mhz = {
  44 +       .pre_div = 0x04,
  45 +       .mult = 0x32,
  46 +       .div = 0x00,
  47 +       .sys_div = 0x05,
  48 +       .adc_div = 0x04
  49 +};
  50 +
  51  static const struct ov7251_pll2_config ov7251_pll2_config_24_mhz = {
  52         .pre_div = 0x04,
  53         .mult = 0x28,
  54 @@ -154,12 +171,18 @@ static const struct ov7251_pll2_config o
  55         .adc_div = 0x04
  56  };
  57
  58 +static const struct ov7251_pll_configs ov7251_pll_configs_19_2_mhz = {
  59 +       .pll1 = &ov7251_pll1_config_19_2_mhz,
  60 +       .pll2 = &ov7251_pll2_config_19_2_mhz
  61 +};
  62 +
  63  static const struct ov7251_pll_configs ov7251_pll_configs_24_mhz = {
  64         .pll1 = &ov7251_pll1_config_24_mhz,
  65         .pll2 = &ov7251_pll2_config_24_mhz
  66  };
  67
  68  static const struct ov7251_pll_configs *ov7251_pll_configs[] = {
  69 +       [OV7251_19_2_MHZ] = &ov7251_pll_configs_19_2_mhz,
  70         [OV7251_24_MHZ] = &ov7251_pll_configs_24_mhz
  71  };
  72
  73 @@ -553,6 +576,7 @@ static const struct reg_value ov7251_set
  74  };
  75
  76  static const unsigned long supported_xclk_rates[] = {
  77 +       [OV7251_19_2_MHZ] = 19200000,
  78         [OV7251_24_MHZ] = 24000000,
  79  };
  80
  81 @@ -1424,6 +1448,7 @@ static int ov7251_probe(struct i2c_clien
  82         struct device *dev = &client->dev;
  83         struct ov7251 *ov7251;
  84         u8 chip_id_high, chip_id_low, chip_rev;
  85 +       unsigned int rate = 0;
  86         int ret;
  87         int i;
  88
  89 @@ -1439,35 +1464,39 @@ static int ov7251_probe(struct i2c_clien
  90                 return ret;
  91
  92         /* get system clock (xclk) */
  93 -       ov7251->xclk = devm_clk_get(dev, "xclk");
  94 +       ov7251->xclk = devm_clk_get(dev, NULL);
  95         if (IS_ERR(ov7251->xclk)) {
  96                 dev_err(dev, "could not get xclk");
  97                 return PTR_ERR(ov7251->xclk);
  98         }
  99
 100 +       /*
 101 +        * We could have either a 24MHz or 19.2MHz clock rate from either dt or
 102 +        * ACPI. We also need to support the IPU3 case which will have both an
 103 +        * external clock AND a clock-frequency property.
 104 +        */
 105         ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
 106 -                                      &ov7251->xclk_freq);
 107 -       if (ret) {
 108 -               dev_err(dev, "could not get xclk frequency\n");
 109 -               return ret;
 110 +                                      &rate);
 111 +       if (!ret && ov7251->xclk) {
 112 +               ret = clk_set_rate(ov7251->xclk, rate);
 113 +               if (ret)
 114 +                       return dev_err_probe(dev, ret,
 115 +                                            "failed to set clock rate\n");
 116 +       } else if (ret && !ov7251->xclk) {
 117 +               return dev_err_probe(dev, ret, "invalid clock config\n");
 118         }
 119
 120 -       /* external clock must be 24MHz, allow 1% tolerance */
 121 -       if (ov7251->xclk_freq < 23760000 || ov7251->xclk_freq > 24240000) {
 122 -               dev_err(dev, "external clock frequency %u is not supported\n",
 123 -                       ov7251->xclk_freq);
 124 -               return -EINVAL;
 125 -       }
 126 +       ov7251->xclk_freq = rate ? rate : clk_get_rate(ov7251->xclk);
 127
 128 -       ret = clk_set_rate(ov7251->xclk, ov7251->xclk_freq);
 129 -       if (ret) {
 130 -               dev_err(dev, "could not set xclk frequency\n");
 131 -               return ret;
 132 -       }
 133         for (i = 0; i < ARRAY_SIZE(supported_xclk_rates); i++)
 134                 if (ov7251->xclk_freq == supported_xclk_rates[i])
 135                         break;
 136
 137 +       if (i == ARRAY_SIZE(supported_xclk_rates))
 138 +               return dev_err_probe(dev, -EINVAL,
 139 +                                    "clock rate %u Hz is unsupported\n",
 140 +                                    ov7251->xclk_freq);
 141 +
 142         ov7251->pll_configs = ov7251_pll_configs[i];
 143
 144         ov7251->io_regulator = devm_regulator_get(dev, "vdddo");