include/linux/auxiliary_bus.h

1 /* SPDX-License-Identifier: GPL-2.0-only */
3  * Copyright (c) 2019-2020 Intel Corporation
5  * Please see Documentation/driver-api/auxiliary_bus.rst for more information.
11 #include <linux/device.h>
20  * responsible for the management of the memory used for the device object.
25  * it is done with the device.  The release() function is then automatically
47  * device which unregisters the auxiliary device object(s).
51  * unregisters the auxiliary device.
55  * struct auxiliary_device - auxiliary device object.
56  * @dev: Device,
57  *       The release and parent fields of the device structure must be filled
59  * @name: Match name found by the auxiliary device driver,
60  * @id: unique identitier if multiple devices of the same name are exported,
62  * An auxiliary_device represents a part of its parent device's functionality.
65  * id that combined with the match_name provide a unique name to register with
66  * the bus subsystem.  For example, a driver registering an auxiliary device is
70  * Registering an auxiliary_device is a three-step process.
73  * sub-device desired.  The name, id, dev.release, and dev.parent fields of
78  * "foo_mod.foo_dev", are registered onto the bus, they must have unique id
81  * unique, then the device_add fails and generates an error message.
84  * be populated with a non-NULL pointer to successfully register the
86  * auxiliary device must be free'ed.  Because once the device is placed on the
91  * drivers device.
99  * call to auxiliary_device_add(), which sets the name of the device and adds
100  * the device to the bus.
102  * .. code-block:: c
111  *	my_aux_dev->name = MY_DEVICE_NAME;
112  *	my_aux_dev->id = my_unique_id_alloc(xxx);
113  *	my_aux_dev->dev.release = my_aux_dev_release;
114  *	my_aux_dev->dev.parent = my_dev;
129  * Unregistering an auxiliary_device is a two-step process to mirror the
133  * .. code-block:: c
135  *         auxiliary_device_delete(my_dev->my_aux_dev);
136  *         auxiliary_device_uninit(my_dev->my_aux_dev);
139 	struct device dev;
145  * struct auxiliary_driver - Definition of an auxiliary bus driver
146  * @probe: Called when a matching device is added to the bus.
147  * @remove: Called when device is removed from the bus.
148  * @shutdown: Called at shut-down time to quiesce the device.
149  * @suspend: Called to put the device to sleep mode. Usually to a power state.
150  * @resume: Called to bring a device from sleep mode.
164  * .. code-block:: c
193 	return dev_get_drvdata(&auxdev->dev);  in auxiliary_get_drvdata()
198 	dev_set_drvdata(&auxdev->dev, data);  in auxiliary_set_drvdata()
201 static inline struct auxiliary_device *to_auxiliary_dev(struct device *dev)  in to_auxiliary_dev()
217 	put_device(&auxdev->dev);  in auxiliary_device_uninit()
222 	device_del(&auxdev->dev);  in auxiliary_device_delete()
233  * module_auxiliary_driver() - Helper macro for registering an auxiliary driver
240  * .. code-block:: c
247 struct auxiliary_device *auxiliary_find_device(struct device *start,
249 					       int (*match)(struct device *dev, const void *data));