1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 1999-2002 Vojtech Pavlik
4 */
5#ifndef _SERIO_H
6#define _SERIO_H
7
8
9#include <linux/types.h>
10#include <linux/interrupt.h>
11#include <linux/list.h>
12#include <linux/spinlock.h>
13#include <linux/mutex.h>
14#include <linux/device.h>
15#include <linux/mod_devicetable.h>
16#include <uapi/linux/serio.h>
17
18extern const struct bus_type serio_bus;
19
20struct serio {
21	void *port_data;
22
23	char name[32];
24	char phys[32];
25	char firmware_id[128];
26
27	bool manual_bind;
28
29	struct serio_device_id id;
30
31	/* Protects critical sections from port's interrupt handler */
32	spinlock_t lock;
33
34	int (*write)(struct serio *, unsigned char);
35	int (*open)(struct serio *);
36	void (*close)(struct serio *);
37	int (*start)(struct serio *);
38	void (*stop)(struct serio *);
39
40	struct serio *parent;
41	/* Entry in parent->children list */
42	struct list_head child_node;
43	struct list_head children;
44	/* Level of nesting in serio hierarchy */
45	unsigned int depth;
46
47	/*
48	 * serio->drv is accessed from interrupt handlers; when modifying
49	 * caller should acquire serio->drv_mutex and serio->lock.
50	 */
51	struct serio_driver *drv;
52	/* Protects serio->drv so attributes can pin current driver */
53	struct mutex drv_mutex;
54
55	struct device dev;
56
57	struct list_head node;
58
59	/*
60	 * For use by PS/2 layer when several ports share hardware and
61	 * may get indigestion when exposed to concurrent access (i8042).
62	 */
63	struct mutex *ps2_cmd_mutex;
64};
65#define to_serio_port(d)	container_of(d, struct serio, dev)
66
67struct serio_driver {
68	const char *description;
69
70	const struct serio_device_id *id_table;
71	bool manual_bind;
72
73	void (*write_wakeup)(struct serio *);
74	irqreturn_t (*interrupt)(struct serio *, unsigned char, unsigned int);
75	int  (*connect)(struct serio *, struct serio_driver *drv);
76	int  (*reconnect)(struct serio *);
77	int  (*fast_reconnect)(struct serio *);
78	void (*disconnect)(struct serio *);
79	void (*cleanup)(struct serio *);
80
81	struct device_driver driver;
82};
83#define to_serio_driver(d)	container_of(d, struct serio_driver, driver)
84
85int serio_open(struct serio *serio, struct serio_driver *drv);
86void serio_close(struct serio *serio);
87void serio_rescan(struct serio *serio);
88void serio_reconnect(struct serio *serio);
89irqreturn_t serio_interrupt(struct serio *serio, unsigned char data, unsigned int flags);
90
91void __serio_register_port(struct serio *serio, struct module *owner);
92
93/* use a define to avoid include chaining to get THIS_MODULE */
94#define serio_register_port(serio) \
95	__serio_register_port(serio, THIS_MODULE)
96
97void serio_unregister_port(struct serio *serio);
98void serio_unregister_child_port(struct serio *serio);
99
100int __must_check __serio_register_driver(struct serio_driver *drv,
101				struct module *owner, const char *mod_name);
102
103/* use a define to avoid include chaining to get THIS_MODULE & friends */
104#define serio_register_driver(drv) \
105	__serio_register_driver(drv, THIS_MODULE, KBUILD_MODNAME)
106
107void serio_unregister_driver(struct serio_driver *drv);
108
109/**
110 * module_serio_driver() - Helper macro for registering a serio driver
111 * @__serio_driver: serio_driver struct
112 *
113 * Helper macro for serio drivers which do not do anything special in
114 * module init/exit. This eliminates a lot of boilerplate. Each module
115 * may only use this macro once, and calling it replaces module_init()
116 * and module_exit().
117 */
118#define module_serio_driver(__serio_driver) \
119	module_driver(__serio_driver, serio_register_driver, \
120		       serio_unregister_driver)
121
122static inline int serio_write(struct serio *serio, unsigned char data)
123{
124	if (serio->write)
125		return serio->write(serio, data);
126	else
127		return -1;
128}
129
130static inline void serio_drv_write_wakeup(struct serio *serio)
131{
132	if (serio->drv && serio->drv->write_wakeup)
133		serio->drv->write_wakeup(serio);
134}
135
136/*
137 * Use the following functions to manipulate serio's per-port
138 * driver-specific data.
139 */
140static inline void *serio_get_drvdata(struct serio *serio)
141{
142	return dev_get_drvdata(&serio->dev);
143}
144
145static inline void serio_set_drvdata(struct serio *serio, void *data)
146{
147	dev_set_drvdata(&serio->dev, data);
148}
149
150/*
151 * Use the following functions to protect critical sections in
152 * driver code from port's interrupt handler
153 */
154static inline void serio_pause_rx(struct serio *serio)
155{
156	spin_lock_irq(&serio->lock);
157}
158
159static inline void serio_continue_rx(struct serio *serio)
160{
161	spin_unlock_irq(&serio->lock);
162}
163
164#endif
165