xref: /linux/include/linux/serio.h (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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/cleanup.h>
10 #include <linux/types.h>
11 #include <linux/interrupt.h>
12 #include <linux/list.h>
13 #include <linux/spinlock.h>
14 #include <linux/mutex.h>
15 #include <linux/device.h>
16 #include <linux/mod_devicetable.h>
17 #include <uapi/linux/serio.h>
18 
19 extern const struct bus_type serio_bus;
20 
21 struct serio {
22 	void *port_data;
23 
24 	char name[32];
25 	char phys[32];
26 	char firmware_id[128];
27 
28 	bool manual_bind;
29 
30 	struct serio_device_id id;
31 
32 	/* Protects critical sections from port's interrupt handler */
33 	spinlock_t lock;
34 
35 	int (*write)(struct serio *, unsigned char);
36 	int (*open)(struct serio *);
37 	void (*close)(struct serio *);
38 	int (*start)(struct serio *);
39 	void (*stop)(struct serio *);
40 
41 	struct serio *parent;
42 	/* Entry in parent->children list */
43 	struct list_head child_node;
44 	struct list_head children;
45 	/* Level of nesting in serio hierarchy */
46 	unsigned int depth;
47 
48 	/*
49 	 * serio->drv is accessed from interrupt handlers; when modifying
50 	 * caller should acquire serio->drv_mutex and serio->lock.
51 	 */
52 	struct serio_driver *drv;
53 	/* Protects serio->drv so attributes can pin current driver */
54 	struct mutex drv_mutex;
55 
56 	struct device dev;
57 
58 	struct list_head node;
59 
60 	/*
61 	 * For use by PS/2 layer when several ports share hardware and
62 	 * may get indigestion when exposed to concurrent access (i8042).
63 	 */
64 	struct mutex *ps2_cmd_mutex;
65 };
66 #define to_serio_port(d)	container_of(d, struct serio, dev)
67 
68 struct serio_driver {
69 	const char *description;
70 
71 	const struct serio_device_id *id_table;
72 	bool manual_bind;
73 
74 	void (*write_wakeup)(struct serio *);
75 	irqreturn_t (*interrupt)(struct serio *, unsigned char, unsigned int);
76 	int  (*connect)(struct serio *, struct serio_driver *drv);
77 	int  (*reconnect)(struct serio *);
78 	int  (*fast_reconnect)(struct serio *);
79 	void (*disconnect)(struct serio *);
80 	void (*cleanup)(struct serio *);
81 
82 	struct device_driver driver;
83 };
84 #define to_serio_driver(d)	container_of_const(d, struct serio_driver, driver)
85 
86 int serio_open(struct serio *serio, struct serio_driver *drv);
87 void serio_close(struct serio *serio);
88 void serio_rescan(struct serio *serio);
89 void serio_reconnect(struct serio *serio);
90 irqreturn_t serio_interrupt(struct serio *serio, unsigned char data, unsigned int flags);
91 
92 void __serio_register_port(struct serio *serio, struct module *owner);
93 
94 /* use a define to avoid include chaining to get THIS_MODULE */
95 #define serio_register_port(serio) \
96 	__serio_register_port(serio, THIS_MODULE)
97 
98 void serio_unregister_port(struct serio *serio);
99 void serio_unregister_child_port(struct serio *serio);
100 
101 int __must_check __serio_register_driver(struct serio_driver *drv,
102 				struct module *owner, const char *mod_name);
103 
104 /* use a define to avoid include chaining to get THIS_MODULE & friends */
105 #define serio_register_driver(drv) \
106 	__serio_register_driver(drv, THIS_MODULE, KBUILD_MODNAME)
107 
108 void serio_unregister_driver(struct serio_driver *drv);
109 
110 /**
111  * module_serio_driver() - Helper macro for registering a serio driver
112  * @__serio_driver: serio_driver struct
113  *
114  * Helper macro for serio drivers which do not do anything special in
115  * module init/exit. This eliminates a lot of boilerplate. Each module
116  * may only use this macro once, and calling it replaces module_init()
117  * and module_exit().
118  */
119 #define module_serio_driver(__serio_driver) \
120 	module_driver(__serio_driver, serio_register_driver, \
121 		       serio_unregister_driver)
122 
123 static inline int serio_write(struct serio *serio, unsigned char data)
124 {
125 	if (serio->write)
126 		return serio->write(serio, data);
127 	else
128 		return -1;
129 }
130 
131 static inline void serio_drv_write_wakeup(struct serio *serio)
132 {
133 	if (serio->drv && serio->drv->write_wakeup)
134 		serio->drv->write_wakeup(serio);
135 }
136 
137 /*
138  * Use the following functions to manipulate serio's per-port
139  * driver-specific data.
140  */
141 static inline void *serio_get_drvdata(struct serio *serio)
142 {
143 	return dev_get_drvdata(&serio->dev);
144 }
145 
146 static inline void serio_set_drvdata(struct serio *serio, void *data)
147 {
148 	dev_set_drvdata(&serio->dev, data);
149 }
150 
151 /*
152  * Use the following functions to protect critical sections in
153  * driver code from port's interrupt handler
154  */
155 static inline void serio_pause_rx(struct serio *serio)
156 {
157 	spin_lock_irq(&serio->lock);
158 }
159 
160 static inline void serio_continue_rx(struct serio *serio)
161 {
162 	spin_unlock_irq(&serio->lock);
163 }
164 
165 DEFINE_GUARD(serio_pause_rx, struct serio *, serio_pause_rx(_T), serio_continue_rx(_T))
166 
167 #endif
168