target/linux/bcm27xx/patches-5.15/950-0720-media-i2c-Provide-ov7251_check_hwcfg.patch

   1 From 3b21da2334113027d91829e1fabe332cf21522a3 Mon Sep 17 00:00:00 2001
   2 From: Daniel Scally <djrscally@gmail.com>
   3 Date: Tue, 15 Feb 2022 23:07:31 +0000
   4 Subject: [PATCH] media: i2c: Provide ov7251_check_hwcfg()
   5
   6 Move the endpoint checking from .probe() to a dedicated function,
   7 and additionally check that the firmware provided link frequencies
   8 are a match for those supported by the driver. Finally, return
   9 -EPROBE_DEFER if the endpoint is not available, as it could be built
  10 by the ipu3-cio2 driver if that probes later.
  11
  12 Signed-off-by: Daniel Scally <djrscally@gmail.com>
  13 ---
  14  drivers/media/i2c/ov7251.c | 84 ++++++++++++++++++++++++++++++--------
  15  1 file changed, 66 insertions(+), 18 deletions(-)
  16
  17 --- a/drivers/media/i2c/ov7251.c
  18 +++ b/drivers/media/i2c/ov7251.c
  19 @@ -1255,11 +1255,74 @@ static const struct v4l2_subdev_ops ov72
  20         .pad = &ov7251_subdev_pad_ops,
  21  };
  22
  23 +static int ov7251_check_hwcfg(struct ov7251 *ov7251)
  24 +{
  25 +       struct fwnode_handle *fwnode = dev_fwnode(ov7251->dev);
  26 +       struct v4l2_fwnode_endpoint bus_cfg = {
  27 +               .bus_type = V4L2_MBUS_CSI2_DPHY,
  28 +       };
  29 +       struct fwnode_handle *endpoint;
  30 +       bool freq_found;
  31 +       int i, j;
  32 +       int ret;
  33 +
  34 +       endpoint = fwnode_graph_get_next_endpoint(fwnode, NULL);
  35 +       if (!endpoint)
  36 +               return -EPROBE_DEFER; /* could be provided by cio2-bridge */
  37 +
  38 +       ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
  39 +       fwnode_handle_put(endpoint);
  40 +       if (ret)
  41 +               return dev_err_probe(ov7251->dev, ret,
  42 +                                    "parsing endpoint node failed\n");
  43 +
  44 +       if (bus_cfg.bus_type != V4L2_MBUS_CSI2_DPHY) {
  45 +               ret = -EINVAL;
  46 +               dev_err(ov7251->dev, "invalid bus type (%u), must be (%u)\n",
  47 +                       bus_cfg.bus_type, V4L2_MBUS_CSI2_DPHY);
  48 +               goto out_free_bus_cfg;
  49 +       }
  50 +
  51 +       if (bus_cfg.bus.mipi_csi2.num_data_lanes != 1) {
  52 +               dev_err(ov7251->dev, "only a 1-lane CSI2 config is supported");
  53 +               ret = -EINVAL;
  54 +               goto out_free_bus_cfg;
  55 +       }
  56 +
  57 +       if (!bus_cfg.nr_of_link_frequencies) {
  58 +               dev_err(ov7251->dev, "no link frequencies defined\n");
  59 +               ret = -EINVAL;
  60 +               goto out_free_bus_cfg;
  61 +       }
  62 +
  63 +       freq_found = false;
  64 +       for (i = 0; i < bus_cfg.nr_of_link_frequencies; i++) {
  65 +               if (freq_found)
  66 +                       break;
  67 +
  68 +               for (j = 0; j < ARRAY_SIZE(link_freq); j++)
  69 +                       if (bus_cfg.link_frequencies[i] == link_freq[j]) {
  70 +                               freq_found = true;
  71 +                               break;
  72 +                       }
  73 +       }
  74 +
  75 +       if (i == bus_cfg.nr_of_link_frequencies) {
  76 +               dev_err(ov7251->dev, "no supported link freq found\n");
  77 +               ret = -EINVAL;
  78 +               goto out_free_bus_cfg;
  79 +       }
  80 +
  81 +out_free_bus_cfg:
  82 +       v4l2_fwnode_endpoint_free(&bus_cfg);
  83 +
  84 +       return ret;
  85 +}
  86 +
  87  static int ov7251_probe(struct i2c_client *client)
  88  {
  89         struct v4l2_fwnode_device_properties props;
  90         struct device *dev = &client->dev;
  91 -       struct fwnode_handle *endpoint;
  92         struct ov7251 *ov7251;
  93         u8 chip_id_high, chip_id_low, chip_rev;
  94         int ret;
  95 @@ -1271,24 +1334,9 @@ static int ov7251_probe(struct i2c_clien
  96         ov7251->i2c_client = client;
  97         ov7251->dev = dev;
  98
  99 -       endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(dev), NULL);
 100 -       if (!endpoint) {
 101 -               dev_err(dev, "endpoint node not found\n");
 102 -               return -EINVAL;
 103 -       }
 104 -
 105 -       ret = v4l2_fwnode_endpoint_parse(endpoint, &ov7251->ep);
 106 -       fwnode_handle_put(endpoint);
 107 -       if (ret < 0) {
 108 -               dev_err(dev, "parsing endpoint node failed\n");
 109 +       ret = ov7251_check_hwcfg(ov7251);
 110 +       if (ret)
 111                 return ret;
 112 -       }
 113 -
 114 -       if (ov7251->ep.bus_type != V4L2_MBUS_CSI2_DPHY) {
 115 -               dev_err(dev, "invalid bus type (%u), must be CSI2 (%u)\n",
 116 -                       ov7251->ep.bus_type, V4L2_MBUS_CSI2_DPHY);
 117 -               return -EINVAL;
 118 -       }
 119
 120         /* get system clock (xclk) */
 121         ov7251->xclk = devm_clk_get(dev, "xclk");