#include <media/v4l2-subdev.h>
#include <media/v4l2-dev.h>
-/* Each instance of a V4L2 device should create the v4l2_device struct,
- either stand-alone or embedded in a larger struct.
-
- It allows easy access to sub-devices (see v4l2-subdev.h) and provides
- basic V4L2 device-level support.
- */
-
#define V4L2_DEVICE_NAME_SIZE (20 + 16)
struct v4l2_ctrl_handler;
+/**
+ * struct v4l2_device - main struct to for V4L2 device drivers
+ *
+ * @dev: pointer to struct device.
+ * @mdev: pointer to struct media_device
+ * @subdevs: used to keep track of the registered subdevs
+ * @lock: lock this struct; can be used by the driver as well
+ * if this struct is embedded into a larger struct.
+ * @name: unique device name, by default the driver name + bus ID
+ * @notify: notify callback called by some sub-devices.
+ * @ctrl_handler: The control handler. May be NULL.
+ * @prio: Device's priority state
+ * @ref: Keep track of the references to this struct.
+ * @release: Release function that is called when the ref count
+ * goes to 0.
+ *
+ * Each instance of a V4L2 device should create the v4l2_device struct,
+ * either stand-alone or embedded in a larger struct.
+ *
+ * It allows easy access to sub-devices (see v4l2-subdev.h) and provides
+ * basic V4L2 device-level support.
+ *
+ * .. note::
+ *
+ * #) dev->driver_data points to this struct.
+ * #) dev might be NULL if there is no parent device
+ */
+
struct v4l2_device {
- /* dev->driver_data points to this struct.
- Note: dev might be NULL if there is no parent device
- as is the case with e.g. ISA devices. */
struct device *dev;
#if defined(CONFIG_MEDIA_CONTROLLER)
struct media_device *mdev;
#endif
- /* used to keep track of the registered subdevs */
struct list_head subdevs;
- /* lock this struct; can be used by the driver as well if this
- struct is embedded into a larger struct. */
spinlock_t lock;
- /* unique device name, by default the driver name + bus ID */
char name[V4L2_DEVICE_NAME_SIZE];
- /* notify callback called by some sub-devices. */
void (*notify)(struct v4l2_subdev *sd,
unsigned int notification, void *arg);
- /* The control handler. May be NULL. */
struct v4l2_ctrl_handler *ctrl_handler;
- /* Device's priority state */
struct v4l2_prio_state prio;
- /* Keep track of the references to this struct. */
struct kref ref;
- /* Release function that is called when the ref count goes to 0. */
void (*release)(struct v4l2_device *v4l2_dev);
};
+/**
+ * v4l2_device_get - gets a V4L2 device reference
+ *
+ * @v4l2_dev: pointer to struct v4l2_device
+ *
+ * This is an ancillary routine meant to increment the usage for the
+ * struct v4l2_device pointed by @v4l2_dev.
+ */
static inline void v4l2_device_get(struct v4l2_device *v4l2_dev)
{
kref_get(&v4l2_dev->ref);
}
+/**
+ * v4l2_device_put - putss a V4L2 device reference
+ *
+ * @v4l2_dev: pointer to struct v4l2_device
+ *
+ * This is an ancillary routine meant to decrement the usage for the
+ * struct v4l2_device pointed by @v4l2_dev.
+ */
int v4l2_device_put(struct v4l2_device *v4l2_dev);
-/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev.
- dev may be NULL in rare cases (ISA devices). In that case you
- must fill in the v4l2_dev->name field before calling this function. */
-int __must_check v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
-
-/* Optional function to initialize the name field of struct v4l2_device using
- the driver name and a driver-global atomic_t instance.
- This function will increment the instance counter and returns the instance
- value used in the name.
-
- Example:
-
- static atomic_t drv_instance = ATOMIC_INIT(0);
-
- ...
-
- instance = v4l2_device_set_name(&v4l2_dev, "foo", &drv_instance);
-
- The first time this is called the name field will be set to foo0 and
- this function returns 0. If the name ends with a digit (e.g. cx18),
- then the name will be set to cx18-0 since cx180 looks really odd. */
+/**
+ * v4l2_device_register -Initialize v4l2_dev and make dev->driver_data
+ * point to v4l2_dev.
+ *
+ * @dev: pointer to struct device
+ * @v4l2_dev: pointer to struct v4l2_device
+ *
+ * .. note::
+ * dev may be NULL in rare cases (ISA devices).
+ * In such case the caller must fill in the v4l2_dev->name field
+ * before calling this function.
+ */
+int __must_check v4l2_device_register(struct device *dev,
+ struct v4l2_device *v4l2_dev);
+
+/**
+ * v4l2_device_set_name - Optional function to initialize the
+ * name field of struct v4l2_device
+ *
+ * @v4l2_dev: pointer to struct v4l2_device
+ * @basename: base name for the device name
+ * @instance: pointer to a static atomic_t var with the instance usage for
+ * the device driver.
+ *
+ * v4l2_device_set_name() initializes the name field of struct v4l2_device
+ * using the driver name and a driver-global atomic_t instance.
+ *
+ * This function will increment the instance counter and returns the
+ * instance value used in the name.
+ *
+ * Example:
+ *
+ * static atomic_t drv_instance = ATOMIC_INIT(0);
+ *
+ * ...
+ *
+ * instance = v4l2_device_set_name(&v4l2_dev, "foo", &drv_instance);
+ *
+ * The first time this is called the name field will be set to foo0 and
+ * this function returns 0. If the name ends with a digit (e.g. cx18),
+ * then the name will be set to cx18-0 since cx180 would look really odd.
+ */
int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
- atomic_t *instance);
-
-/* Set v4l2_dev->dev to NULL. Call when the USB parent disconnects.
- Since the parent disappears this ensures that v4l2_dev doesn't have an
- invalid parent pointer. */
+ atomic_t *instance);
+
+/**
+ * v4l2_device_disconnect - Change V4L2 device state to disconnected.
+ *
+ * @v4l2_dev: pointer to struct v4l2_device
+ *
+ * Should be called when the USB parent disconnects.
+ * Since the parent disappears, this ensures that v4l2_dev doesn't have
+ * an invalid parent pointer.
+ *
+ * .. note:: This function sets v4l2_dev->dev to NULL.
+ */
void v4l2_device_disconnect(struct v4l2_device *v4l2_dev);
-/* Unregister all sub-devices and any other resources related to v4l2_dev. */
+/**
+ * v4l2_device_unregister - Unregister all sub-devices and any other
+ * resources related to v4l2_dev.
+ *
+ * @v4l2_dev: pointer to struct v4l2_device
+ */
void v4l2_device_unregister(struct v4l2_device *v4l2_dev);
-/* Register a subdev with a v4l2 device. While registered the subdev module
- is marked as in-use. An error is returned if the module is no longer
- loaded when you attempt to register it. */
+/**
+ * v4l2_device_register_subdev - Registers a subdev with a v4l2 device.
+ *
+ * @v4l2_dev: pointer to struct v4l2_device
+ * @sd: pointer to struct v4l2_subdev
+ *
+ * While registered, the subdev module is marked as in-use.
+ *
+ * An error is returned if the module is no longer loaded on any attempts
+ * to register it.
+ */
int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
- struct v4l2_subdev *sd);
-/* Unregister a subdev with a v4l2 device. Can also be called if the subdev
- wasn't registered. In that case it will do nothing. */
+ struct v4l2_subdev *sd);
+
+/**
+ * v4l2_device_unregister_subdev - Unregisters a subdev with a v4l2 device.
+ *
+ * @sd: pointer to struct v4l2_subdev
+ *
+ * .. note ::
+ *
+ * Can also be called if the subdev wasn't registered. In such
+ * case, it will do nothing.
+ */
void v4l2_device_unregister_subdev(struct v4l2_subdev *sd);
-/* Register device nodes for all subdev of the v4l2 device that are marked with
- * the V4L2_SUBDEV_FL_HAS_DEVNODE flag.
+/**
+ * v4l2_device_register_subdev_nodes - Registers device nodes for all subdevs
+ * of the v4l2 device that are marked with
+ * the V4L2_SUBDEV_FL_HAS_DEVNODE flag.
+ *
+ * @v4l2_dev: pointer to struct v4l2_device
*/
int __must_check
v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev);
-/* Send a notification to v4l2_device. */
+/**
+ * v4l2_subdev_notify - Sends a notification to v4l2_device.
+ *
+ * @sd: pointer to struct v4l2_subdev
+ * @notification: type of notification. Please notice that the notification
+ * type is driver-specific.
+ * @arg: arguments for the notification. Those are specific to each
+ * notification type.
+ */
static inline void v4l2_subdev_notify(struct v4l2_subdev *sd,
unsigned int notification, void *arg)
{
projects / cascardo / linux.git / commitdiff