media: atomisp: gc0310: Add check_hwcfg() function

Add a check_hwcfg() function to check if the external clk-freq, CSI
link-freq and lane-count match the driver's expectations.

Signed-off-by: Hans de Goede <hansg@kernel.org>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://lore.kernel.org/r/20250517114106.43494-12-hansg@kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/staging/media/atomisp/i2c/atomisp-gc0310.c b/drivers/staging/media/atomisp/i2c/atomisp-gc0310.c
index 3e94414be6c79778ad7d5d1fe9bebec912c6affb..f3dbc3583d97bce54c7aa8781a1c0ccc79cff932 100644 (file)
--- a/drivers/staging/media/atomisp/i2c/atomisp-gc0310.c
+++ b/drivers/staging/media/atomisp/i2c/atomisp-gc0310.c
@@ -36,6 +36,7 @@
 #define GC0310_PIXELRATE                       13923000
 /* single lane, bus-format is 8 bpp, CSI-2 is double data rate */
 #define GC0310_LINK_FREQ                       (GC0310_PIXELRATE * 8 / 2)
+#define GC0310_MCLK_FREQ                       19200000
 #define GC0310_FPS                             30
 #define GC0310_SKIP_FRAMES                     3
 
@@ -664,21 +665,68 @@ static void gc0310_remove(struct i2c_client *client)
        pm_runtime_disable(&client->dev);
 }
 
-static int gc0310_probe(struct i2c_client *client)
+static int gc0310_check_hwcfg(struct device *dev)
 {
+       struct v4l2_fwnode_endpoint bus_cfg = {
+               .bus_type = V4L2_MBUS_CSI2_DPHY,
+       };
        struct fwnode_handle *ep_fwnode;
-       struct gc0310_device *sensor;
+       unsigned long link_freq_bitmap;
+       u32 mclk;
        int ret;
 
        /*
         * Sometimes the fwnode graph is initialized by the bridge driver.
         * Bridge drivers doing this may also add GPIO mappings, wait for this.
         */
-       ep_fwnode = fwnode_graph_get_next_endpoint(dev_fwnode(&client->dev), NULL);
+       ep_fwnode = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
        if (!ep_fwnode)
-               return dev_err_probe(&client->dev, -EPROBE_DEFER, "waiting for fwnode graph endpoint\n");
+               return dev_err_probe(dev, -EPROBE_DEFER,
+                                    "waiting for fwnode graph endpoint\n");
+
+       ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
+                                      &mclk);
+       if (ret) {
+               fwnode_handle_put(ep_fwnode);
+               return dev_err_probe(dev, ret,
+                                    "reading clock-frequency property\n");
+       }
 
+       if (mclk != GC0310_MCLK_FREQ) {
+               fwnode_handle_put(ep_fwnode);
+               return dev_err_probe(dev, -EINVAL,
+                                    "external clock %u is not supported\n",
+                                    mclk);
+       }
+
+       ret = v4l2_fwnode_endpoint_alloc_parse(ep_fwnode, &bus_cfg);
        fwnode_handle_put(ep_fwnode);
+       if (ret)
+               return dev_err_probe(dev, ret, "parsing endpoint failed\n");
+
+       ret = v4l2_link_freq_to_bitmap(dev, bus_cfg.link_frequencies,
+                                      bus_cfg.nr_of_link_frequencies,
+                                      link_freq_menu_items,
+                                      ARRAY_SIZE(link_freq_menu_items),
+                                      &link_freq_bitmap);
+
+       if (ret == 0 && bus_cfg.bus.mipi_csi2.num_data_lanes != 1)
+               ret = dev_err_probe(dev, -EINVAL,
+                                   "number of CSI2 data lanes %u is not supported\n",
+                                   bus_cfg.bus.mipi_csi2.num_data_lanes);
+
+       v4l2_fwnode_endpoint_free(&bus_cfg);
+       return ret;
+}
+
+static int gc0310_probe(struct i2c_client *client)
+{
+       struct gc0310_device *sensor;
+       int ret;
+
+       ret = gc0310_check_hwcfg(&client->dev);
+       if (ret)
+               return ret;
 
        sensor = devm_kzalloc(&client->dev, sizeof(*sensor), GFP_KERNEL);
        if (!sensor)