/* * V4L2 asynchronous subdevice registration API * * Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #ifndef V4L2_ASYNC_H #define V4L2_ASYNC_H #include <linux/list.h> #include <linux/mutex.h> 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 /** * enum v4l2_async_match_type - type of asynchronous subdevice logic to be used * in order to identify a match * * @V4L2_ASYNC_MATCH_CUSTOM: Match will use the logic provided by &struct * v4l2_async_subdev.match ops * @V4L2_ASYNC_MATCH_DEVNAME: Match will use the device name * @V4L2_ASYNC_MATCH_I2C: Match will check for I2C adapter ID and address * @V4L2_ASYNC_MATCH_FWNODE: Match will use firmware node * * This enum is used by the asyncrhronous sub-device logic to define the * algorithm that will be used to match an asynchronous device. */ enum v4l2_async_match_type { V4L2_ASYNC_MATCH_CUSTOM, V4L2_ASYNC_MATCH_DEVNAME, V4L2_ASYNC_MATCH_I2C, V4L2_ASYNC_MATCH_FWNODE, }; /** * struct v4l2_async_subdev - sub-device descriptor, as known to a bridge * * @match_type: type of match that will be used * @match: union of per-bus type matching data sets * @match.fwnode: * pointer to &struct fwnode_handle to be matched. * Used if @match_type is %V4L2_ASYNC_MATCH_FWNODE. * @match.device_name: * string containing the device name to be matched. * Used if @match_type is %V4L2_ASYNC_MATCH_DEVNAME. * @match.i2c: embedded struct with I2C parameters to be matched. * Both @match.i2c.adapter_id and @match.i2c.address * should be matched. * Used if @match_type is %V4L2_ASYNC_MATCH_I2C. * @match.i2c.adapter_id: * I2C adapter ID to be matched. * Used if @match_type is %V4L2_ASYNC_MATCH_I2C. * @match.i2c.address: * I2C address to be matched. * Used if @match_type is %V4L2_ASYNC_MATCH_I2C. * @match.custom: * Driver-specific match criteria. * Used if @match_type is %V4L2_ASYNC_MATCH_CUSTOM. * @match.custom.match: * Driver-specific match function to be used if * %V4L2_ASYNC_MATCH_CUSTOM. * @match.custom.priv: * Driver-specific private struct with match parameters * to be used if %V4L2_ASYNC_MATCH_CUSTOM. * @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; union { struct fwnode_handle *fwnode; const char *device_name; struct { int adapter_id; unsigned short address; } i2c; struct { bool (*match)(struct device *, struct v4l2_async_subdev *); void *priv; } custom; } match; /* v4l2-async core private: not to be used by drivers */ struct list_head list; }; /** * struct v4l2_async_notifier_operations - Asynchronous V4L2 notifier operations * @bound: a subdevice driver has successfully probed one of the subdevices * @complete: All subdevices have been probed successfully. The complete * callback is only executed for the root notifier. * @unbind: a subdevice is leaving */ struct v4l2_async_notifier_operations { int (*bound)(struct v4l2_async_notifier *notifier, struct v4l2_subdev *subdev, struct v4l2_async_subdev *asd); int (*complete)(struct v4l2_async_notifier *notifier); void (*unbind)(struct v4l2_async_notifier *notifier, struct v4l2_subdev *subdev, struct v4l2_async_subdev *asd); }; /** * struct v4l2_async_notifier - v4l2_device notifier data * * @ops: notifier operations * @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: v4l2_device of the root notifier, NULL otherwise * @sd: sub-device that registered the notifier, NULL otherwise * @parent: parent notifier * @waiting: list of struct v4l2_async_subdev, waiting for their drivers * @done: list of struct v4l2_subdev, already probed * @list: member in a global list of notifiers */ struct v4l2_async_notifier { const struct v4l2_async_notifier_operations *ops; unsigned int num_subdevs; unsigned int max_subdevs; struct v4l2_async_subdev **subdevs; struct v4l2_device *v4l2_dev; struct v4l2_subdev *sd; struct v4l2_async_notifier *parent; struct list_head waiting; struct list_head done; struct list_head list; }; /** * v4l2_async_notifier_register - registers a subdevice asynchronous notifier * * @v4l2_dev: pointer to &struct v4l2_device * @notifier: pointer to &struct v4l2_async_notifier */ int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev, struct v4l2_async_notifier *notifier); /** * v4l2_async_subdev_notifier_register - registers a subdevice asynchronous * notifier for a sub-device * * @sd: pointer to &struct v4l2_subdev * @notifier: pointer to &struct v4l2_async_notifier */ int v4l2_async_subdev_notifier_register(struct v4l2_subdev *sd, struct v4l2_async_notifier *notifier); /** * v4l2_async_notifier_unregister - unregisters a subdevice asynchronous notifier * * @notifier: pointer to &struct v4l2_async_notifier */ 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 or * @v4l2_fwnode_reference_parse_sensor_common. * * 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 * * @sd: pointer to &struct v4l2_subdev */ int v4l2_async_register_subdev(struct v4l2_subdev *sd); /** * v4l2_async_register_subdev_sensor_common - registers a sensor sub-device to * the asynchronous sub-device * framework and parse set up common * sensor related devices * * @sd: pointer to struct &v4l2_subdev * * This function is just like v4l2_async_register_subdev() with the exception * that calling it will also parse firmware interfaces for remote references * using v4l2_async_notifier_parse_fwnode_sensor_common() and registers the * async sub-devices. The sub-device is similarly unregistered by calling * v4l2_async_unregister_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_async_register_subdev_sensor_common( struct v4l2_subdev *sd); /** * v4l2_async_unregister_subdev - unregisters a sub-device to the asynchronous * subdevice framework * * @sd: pointer to &struct v4l2_subdev */ void v4l2_async_unregister_subdev(struct v4l2_subdev *sd); #endif