xref: /linux/include/linux/serio.h (revision dbcedec3a31119d7594baacc743300d127c99c56)
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 
18 extern const struct bus_type serio_bus;
19 
20 struct 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 
67 struct 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 
85 int serio_open(struct serio *serio, struct serio_driver *drv);
86 void serio_close(struct serio *serio);
87 void serio_rescan(struct serio *serio);
88 void serio_reconnect(struct serio *serio);
89 irqreturn_t serio_interrupt(struct serio *serio, unsigned char data, unsigned int flags);
90 
91 void __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 
97 void serio_unregister_port(struct serio *serio);
98 void serio_unregister_child_port(struct serio *serio);
99 
100 int __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 
107 void 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 
122 static 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 
130 static 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  */
140 static inline void *serio_get_drvdata(struct serio *serio)
141 {
142 	return dev_get_drvdata(&serio->dev);
143 }
144 
145 static 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  */
154 static inline void serio_pause_rx(struct serio *serio)
155 {
156 	spin_lock_irq(&serio->lock);
157 }
158 
159 static inline void serio_continue_rx(struct serio *serio)
160 {
161 	spin_unlock_irq(&serio->lock);
162 }
163 
164 #endif
165