V4L/DVB (13310): uvcvideo: Return -EINVAL instead of -ENODEV in read()

[safe/jmp/linux-2.6] / drivers / media / video / v4l2-device.c

diff --git a/drivers/media/video/v4l2-device.c b/drivers/media/video/v4l2-device.c
index cf9d4c7..0d06e7c 100644 (file)
--- a/drivers/media/video/v4l2-device.c
+++ b/drivers/media/video/v4l2-device.c
@@ -26,48 +26,95 @@
 
 int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev)
 {
-       if (dev == NULL || v4l2_dev == NULL)
+       if (v4l2_dev == NULL)
                return -EINVAL;
-       /* Warn if we apparently re-register a device */
-       WARN_ON(dev_get_drvdata(dev) != NULL);
+
        INIT_LIST_HEAD(&v4l2_dev->subdevs);
        spin_lock_init(&v4l2_dev->lock);
        v4l2_dev->dev = dev;
-       snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
-                       dev->driver->name, dev->bus_id);
+       if (dev == NULL) {
+               /* If dev == NULL, then name must be filled in by the caller */
+               WARN_ON(!v4l2_dev->name[0]);
+               return 0;
+       }
+
+       /* Set name to driver name + device name if it is empty. */
+       if (!v4l2_dev->name[0])
+               snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
+                       dev->driver->name, dev_name(dev));
+       if (dev_get_drvdata(dev))
+               v4l2_warn(v4l2_dev, "Non-NULL drvdata on register\n");
        dev_set_drvdata(dev, v4l2_dev);
        return 0;
 }
 EXPORT_SYMBOL_GPL(v4l2_device_register);
 
+int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
+                                               atomic_t *instance)
+{
+       int num = atomic_inc_return(instance) - 1;
+       int len = strlen(basename);
+
+       if (basename[len - 1] >= '0' && basename[len - 1] <= '9')
+               snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
+                               "%s-%d", basename, num);
+       else
+               snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
+                               "%s%d", basename, num);
+       return num;
+}
+EXPORT_SYMBOL_GPL(v4l2_device_set_name);
+
+void v4l2_device_disconnect(struct v4l2_device *v4l2_dev)
+{
+       if (v4l2_dev->dev) {
+               dev_set_drvdata(v4l2_dev->dev, NULL);
+               v4l2_dev->dev = NULL;
+       }
+}
+EXPORT_SYMBOL_GPL(v4l2_device_disconnect);
+
 void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
 {
        struct v4l2_subdev *sd, *next;
 
-       if (v4l2_dev == NULL || v4l2_dev->dev == NULL)
+       if (v4l2_dev == NULL)
                return;
-       dev_set_drvdata(v4l2_dev->dev, NULL);
-       /* unregister subdevs */
-       list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list)
+       v4l2_device_disconnect(v4l2_dev);
+
+       /* Unregister subdevs */
+       list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) {
                v4l2_device_unregister_subdev(sd);
+#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
+               if (sd->flags & V4L2_SUBDEV_FL_IS_I2C) {
+                       struct i2c_client *client = v4l2_get_subdevdata(sd);
 
-       v4l2_dev->dev = NULL;
+                       /* We need to unregister the i2c client explicitly.
+                          We cannot rely on i2c_del_adapter to always
+                          unregister clients for us, since if the i2c bus
+                          is a platform bus, then it is never deleted. */
+                       if (client)
+                               i2c_unregister_device(client);
+               }
+#endif
+       }
 }
 EXPORT_SYMBOL_GPL(v4l2_device_unregister);
 
-int v4l2_device_register_subdev(struct v4l2_device *dev, struct v4l2_subdev *sd)
+int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
+                                               struct v4l2_subdev *sd)
 {
        /* Check for valid input */
-       if (dev == NULL || sd == NULL || !sd->name[0])
+       if (v4l2_dev == NULL || sd == NULL || !sd->name[0])
                return -EINVAL;
        /* Warn if we apparently re-register a subdev */
-       WARN_ON(sd->dev != NULL);
+       WARN_ON(sd->v4l2_dev != NULL);
        if (!try_module_get(sd->owner))
                return -ENODEV;
-       sd->dev = dev;
-       spin_lock(&dev->lock);
-       list_add_tail(&sd->list, &dev->subdevs);
-       spin_unlock(&dev->lock);
+       sd->v4l2_dev = v4l2_dev;
+       spin_lock(&v4l2_dev->lock);
+       list_add_tail(&sd->list, &v4l2_dev->subdevs);
+       spin_unlock(&v4l2_dev->lock);
        return 0;
 }
 EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
@@ -75,12 +122,12 @@ EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
 void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
 {
        /* return if it isn't registered */
-       if (sd == NULL || sd->dev == NULL)
+       if (sd == NULL || sd->v4l2_dev == NULL)
                return;
-       spin_lock(&sd->dev->lock);
+       spin_lock(&sd->v4l2_dev->lock);
        list_del(&sd->list);
-       spin_unlock(&sd->dev->lock);
-       sd->dev = NULL;
+       spin_unlock(&sd->v4l2_dev->lock);
+       sd->v4l2_dev = NULL;
        module_put(sd->owner);
 }
 EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);