diff options
Diffstat (limited to 'include/media')
| -rw-r--r-- | include/media/v4l2-async.h | 24 | ||||
| -rw-r--r-- | include/media/v4l2-fwnode.h | 118 |
2 files changed, 140 insertions, 2 deletions
diff --git a/include/media/v4l2-async.h b/include/media/v4l2-async.h index c69d8c8a66d0..329aeebd1a80 100644 --- a/include/media/v4l2-async.h +++ b/include/media/v4l2-async.h @@ -18,7 +18,6 @@ struct device; struct device_node; struct v4l2_device; struct v4l2_subdev; -struct v4l2_async_notifier; /* A random max subdevice number, used to allocate an array on stack */ #define V4L2_MAX_SUBDEVS 128U @@ -50,6 +49,10 @@ enum v4l2_async_match_type { * @match: union of per-bus type matching data sets * @list: used to link struct v4l2_async_subdev objects, waiting to be * probed, to a notifier->waiting list + * + * When this struct is used as a member in a driver specific struct, + * the driver specific struct shall contain the &struct + * v4l2_async_subdev as its first member. */ struct v4l2_async_subdev { enum v4l2_async_match_type match_type; @@ -78,7 +81,8 @@ struct v4l2_async_subdev { /** * struct v4l2_async_notifier - v4l2_device notifier data * - * @num_subdevs: number of subdevices + * @num_subdevs: number of subdevices used in the subdevs array + * @max_subdevs: number of subdevices allocated in the subdevs array * @subdevs: array of pointers to subdevice descriptors * @v4l2_dev: pointer to struct v4l2_device * @waiting: list of struct v4l2_async_subdev, waiting for their drivers @@ -90,6 +94,7 @@ struct v4l2_async_subdev { */ struct v4l2_async_notifier { unsigned int num_subdevs; + unsigned int max_subdevs; struct v4l2_async_subdev **subdevs; struct v4l2_device *v4l2_dev; struct list_head waiting; @@ -121,6 +126,21 @@ int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev, void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier); /** + * v4l2_async_notifier_cleanup - clean up notifier resources + * @notifier: the notifier the resources of which are to be cleaned up + * + * Release memory resources related to a notifier, including the async + * sub-devices allocated for the purposes of the notifier but not the notifier + * itself. The user is responsible for calling this function to clean up the + * notifier after calling @v4l2_async_notifier_parse_fwnode_endpoints. + * + * There is no harm from calling v4l2_async_notifier_cleanup in other + * cases as long as its memory has been zeroed after it has been + * allocated. + */ +void v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier); + +/** * v4l2_async_register_subdev - registers a sub-device to the asynchronous * subdevice framework * diff --git a/include/media/v4l2-fwnode.h b/include/media/v4l2-fwnode.h index 7adec9851d9e..ac605af9b877 100644 --- a/include/media/v4l2-fwnode.h +++ b/include/media/v4l2-fwnode.h @@ -25,6 +25,8 @@ #include <media/v4l2-mediabus.h> struct fwnode_handle; +struct v4l2_async_notifier; +struct v4l2_async_subdev; #define V4L2_FWNODE_CSI2_MAX_DATA_LANES 4 @@ -122,4 +124,120 @@ int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode, struct v4l2_fwnode_link *link); void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link); +/** + * v4l2_async_notifier_parse_fwnode_endpoints - Parse V4L2 fwnode endpoints in a + * device node + * @dev: the device the endpoints of which are to be parsed + * @notifier: notifier for @dev + * @asd_struct_size: size of the driver's async sub-device struct, including + * sizeof(struct v4l2_async_subdev). The &struct + * v4l2_async_subdev shall be the first member of + * the driver's async sub-device struct, i.e. both + * begin at the same memory address. + * @parse_endpoint: Driver's callback function called on each V4L2 fwnode + * endpoint. Optional. + * Return: %0 on success + * %-ENOTCONN if the endpoint is to be skipped but this + * should not be considered as an error + * %-EINVAL if the endpoint configuration is invalid + * + * Parse the fwnode endpoints of the @dev device and populate the async sub- + * devices array of the notifier. The @parse_endpoint callback function is + * called for each endpoint with the corresponding async sub-device pointer to + * let the caller initialize the driver-specific part of the async sub-device + * structure. + * + * The notifier memory shall be zeroed before this function is called on the + * notifier. + * + * This function may not be called on a registered notifier and may be called on + * a notifier only once. + * + * Do not change the notifier's subdevs array, take references to the subdevs + * array itself or change the notifier's num_subdevs field. This is because this + * function allocates and reallocates the subdevs array based on parsing + * endpoints. + * + * The &struct v4l2_fwnode_endpoint passed to the callback function + * @parse_endpoint is released once the function is finished. If there is a need + * to retain that configuration, the user needs to allocate memory for it. + * + * Any notifier populated using this function must be released with a call to + * v4l2_async_notifier_cleanup() after it has been unregistered and the async + * sub-devices are no longer in use, even if the function returned an error. + * + * Return: %0 on success, including when no async sub-devices are found + * %-ENOMEM if memory allocation failed + * %-EINVAL if graph or endpoint parsing failed + * Other error codes as returned by @parse_endpoint + */ +int v4l2_async_notifier_parse_fwnode_endpoints( + struct device *dev, struct v4l2_async_notifier *notifier, + size_t asd_struct_size, + int (*parse_endpoint)(struct device *dev, + struct v4l2_fwnode_endpoint *vep, + struct v4l2_async_subdev *asd)); + +/** + * v4l2_async_notifier_parse_fwnode_endpoints_by_port - Parse V4L2 fwnode + * endpoints of a port in a + * device node + * @dev: the device the endpoints of which are to be parsed + * @notifier: notifier for @dev + * @asd_struct_size: size of the driver's async sub-device struct, including + * sizeof(struct v4l2_async_subdev). The &struct + * v4l2_async_subdev shall be the first member of + * the driver's async sub-device struct, i.e. both + * begin at the same memory address. + * @port: port number where endpoints are to be parsed + * @parse_endpoint: Driver's callback function called on each V4L2 fwnode + * endpoint. Optional. + * Return: %0 on success + * %-ENOTCONN if the endpoint is to be skipped but this + * should not be considered as an error + * %-EINVAL if the endpoint configuration is invalid + * + * This function is just like v4l2_async_notifier_parse_fwnode_endpoints() with + * the exception that it only parses endpoints in a given port. This is useful + * on devices that have both sinks and sources: the async sub-devices connected + * to sources have already been configured by another driver (on capture + * devices). In this case the driver must know which ports to parse. + * + * Parse the fwnode endpoints of the @dev device on a given @port and populate + * the async sub-devices array of the notifier. The @parse_endpoint callback + * function is called for each endpoint with the corresponding async sub-device + * pointer to let the caller initialize the driver-specific part of the async + * sub-device structure. + * + * The notifier memory shall be zeroed before this function is called on the + * notifier the first time. + * + * This function may not be called on a registered notifier and may be called on + * a notifier only once per port. + * + * Do not change the notifier's subdevs array, take references to the subdevs + * array itself or change the notifier's num_subdevs field. This is because this + * function allocates and reallocates the subdevs array based on parsing + * endpoints. + * + * The &struct v4l2_fwnode_endpoint passed to the callback function + * @parse_endpoint is released once the function is finished. If there is a need + * to retain that configuration, the user needs to allocate memory for it. + * + * Any notifier populated using this function must be released with a call to + * v4l2_async_notifier_cleanup() after it has been unregistered and the async + * sub-devices are no longer in use, even if the function returned an error. + * + * Return: %0 on success, including when no async sub-devices are found + * %-ENOMEM if memory allocation failed + * %-EINVAL if graph or endpoint parsing failed + * Other error codes as returned by @parse_endpoint + */ +int v4l2_async_notifier_parse_fwnode_endpoints_by_port( + struct device *dev, struct v4l2_async_notifier *notifier, + size_t asd_struct_size, unsigned int port, + int (*parse_endpoint)(struct device *dev, + struct v4l2_fwnode_endpoint *vep, + struct v4l2_async_subdev *asd)); + #endif /* _V4L2_FWNODE_H */ |