xref: /linux/include/linux/reset-controller.h (revision 208eed95fc710827b100266c9450ae84d46727bd)
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 
7 struct reset_controller_dev;
8 
9 /**
10  * struct reset_control_ops - reset controller driver callbacks
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  */
18 struct 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 
25 struct module;
26 struct device_node;
27 struct of_phandle_args;
28 
29 /**
30  * struct reset_controller_dev - reset controller entity that might
31  *                               provide multiple reset controls
32  * @ops: a pointer to device specific struct reset_control_ops
33  * @owner: kernel module of the reset controller driver
34  * @list: internal list of reset controller devices
35  * @reset_control_head: head of internal list of requested reset controls
36  * @dev: corresponding driver model device struct
37  * @of_node: corresponding device tree node as phandle target
38  * @of_args: for reset-gpios controllers: corresponding phandle args with
39  *           of_node and GPIO number complementing of_node; either this or
40  *           of_node should be present
41  * @of_reset_n_cells: number of cells in reset line specifiers
42  * @of_xlate: translation function to translate from specifier as found in the
43  *            device tree to id as given to the reset control ops, defaults
44  *            to :c:func:`of_reset_simple_xlate`.
45  * @nr_resets: number of reset controls in this reset controller device
46  */
47 struct reset_controller_dev {
48 	const struct reset_control_ops *ops;
49 	struct module *owner;
50 	struct list_head list;
51 	struct list_head reset_control_head;
52 	struct device *dev;
53 	struct device_node *of_node;
54 	const struct of_phandle_args *of_args;
55 	int of_reset_n_cells;
56 	int (*of_xlate)(struct reset_controller_dev *rcdev,
57 			const struct of_phandle_args *reset_spec);
58 	unsigned int nr_resets;
59 };
60 
61 #if IS_ENABLED(CONFIG_RESET_CONTROLLER)
62 int reset_controller_register(struct reset_controller_dev *rcdev);
63 void reset_controller_unregister(struct reset_controller_dev *rcdev);
64 
65 struct device;
66 int devm_reset_controller_register(struct device *dev,
67 				   struct reset_controller_dev *rcdev);
68 #else
reset_controller_register(struct reset_controller_dev * rcdev)69 static inline int reset_controller_register(struct reset_controller_dev *rcdev)
70 {
71 	return 0;
72 }
73 
reset_controller_unregister(struct reset_controller_dev * rcdev)74 static inline void reset_controller_unregister(struct reset_controller_dev *rcdev)
75 {
76 }
77 
devm_reset_controller_register(struct device * dev,struct reset_controller_dev * rcdev)78 static inline int devm_reset_controller_register(struct device *dev,
79 						 struct reset_controller_dev *rcdev)
80 {
81 	return 0;
82 }
83 #endif
84 
85 #endif
86