1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_RESET_CONTROLLER_H_
3#define _LINUX_RESET_CONTROLLER_H_
4
5#include <linux/list.h>
6
7struct reset_controller_dev;
8
9/**
10 * struct reset_control_ops
11 *
12 * @reset: for self-deasserting resets, does all necessary
13 * things to reset the device
14 * @assert: manually assert the reset line, if supported
15 * @deassert: manually deassert the reset line, if supported
16 * @status: return the status of the reset line, if supported
17 */
18struct reset_control_ops {
19 int (*reset)(struct reset_controller_dev *rcdev, unsigned long id);
20 int (*assert)(struct reset_controller_dev *rcdev, unsigned long id);
21 int (*deassert)(struct reset_controller_dev *rcdev, unsigned long id);
22 int (*status)(struct reset_controller_dev *rcdev, unsigned long id);
23};
24
25struct module;
26struct device_node;
27struct of_phandle_args;
28
29/**
30 * struct reset_control_lookup - represents a single lookup entry
31 *
32 * @list: internal list of all reset lookup entries
33 * @provider: name of the reset controller device controlling this reset line
34 * @index: ID of the reset controller in the reset controller device
35 * @dev_id: name of the device associated with this reset line
36 * @con_id name of the reset line (can be NULL)
37 */
38struct reset_control_lookup {
39 struct list_head list;
40 const char *provider;
41 unsigned int index;
42 const char *dev_id;
43 const char *con_id;
44};
45
46#define RESET_LOOKUP(_provider, _index, _dev_id, _con_id) \
47 { \
48 .provider = _provider, \
49 .index = _index, \
50 .dev_id = _dev_id, \
51 .con_id = _con_id, \
52 }
53
54/**
55 * struct reset_controller_dev - reset controller entity that might
56 * provide multiple reset controls
57 * @ops: a pointer to device specific struct reset_control_ops
58 * @owner: kernel module of the reset controller driver
59 * @list: internal list of reset controller devices
60 * @reset_control_head: head of internal list of requested reset controls
61 * @dev: corresponding driver model device struct
62 * @of_node: corresponding device tree node as phandle target
63 * @of_reset_n_cells: number of cells in reset line specifiers
64 * @of_xlate: translation function to translate from specifier as found in the
65 * device tree to id as given to the reset control ops
66 * @nr_resets: number of reset controls in this reset controller device
67 */
68struct reset_controller_dev {
69 const struct reset_control_ops *ops;
70 struct module *owner;
71 struct list_head list;
72 struct list_head reset_control_head;
73 struct device *dev;
74 struct device_node *of_node;
75 int of_reset_n_cells;
76 int (*of_xlate)(struct reset_controller_dev *rcdev,
77 const struct of_phandle_args *reset_spec);
78 unsigned int nr_resets;
79};
80
81int reset_controller_register(struct reset_controller_dev *rcdev);
82void reset_controller_unregister(struct reset_controller_dev *rcdev);
83
84struct device;
85int devm_reset_controller_register(struct device *dev,
86 struct reset_controller_dev *rcdev);
87
88void reset_controller_add_lookup(struct reset_control_lookup *lookup,
89 unsigned int num_entries);
90
91#endif
92