xref: /freebsd/sys/dev/evdev/evdev_private.h (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*-
2  * Copyright (c) 2014 Jakub Wojciech Klama <jceel@FreeBSD.org>
3  * Copyright (c) 2015-2016 Vladimir Kondratyev <wulf@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 #ifndef	_DEV_EVDEV_EVDEV_PRIVATE_H
31 #define	_DEV_EVDEV_EVDEV_PRIVATE_H
32 
33 #include <sys/bitstring.h>
34 #include <sys/ck.h>
35 #include <sys/epoch.h>
36 #include <sys/kbio.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/mutex.h>
40 #include <sys/queue.h>
41 #include <sys/selinfo.h>
42 #include <sys/sx.h>
43 #include <sys/sysctl.h>
44 
45 #include <dev/evdev/evdev.h>
46 #include <dev/evdev/input.h>
47 #include <dev/kbd/kbdreg.h>
48 
49 #define	NAMELEN		80
50 
51 /*
52  * bitstr_t implementation must be identical to one found in EVIOCG*
53  * libevdev ioctls. Our bitstring(3) API is compatible since r299090.
54  */
55 _Static_assert(sizeof(bitstr_t) == sizeof(unsigned long),
56     "bitstr_t size mismatch");
57 
58 MALLOC_DECLARE(M_EVDEV);
59 
60 struct evdev_client;
61 struct evdev_mt;
62 
63 #define	CURRENT_MT_SLOT(evdev)	((evdev)->ev_absinfo[ABS_MT_SLOT].value)
64 #define	MAXIMAL_MT_SLOT(evdev)	((evdev)->ev_absinfo[ABS_MT_SLOT].maximum)
65 
66 enum evdev_key_events
67 {
68 	KEY_EVENT_UP,
69 	KEY_EVENT_DOWN,
70 	KEY_EVENT_REPEAT
71 };
72 
73 /* evdev clock IDs in Linux semantic */
74 enum evdev_clock_id
75 {
76 	EV_CLOCK_REALTIME = 0,	/* UTC clock */
77 	EV_CLOCK_MONOTONIC,	/* monotonic, stops on suspend */
78 	EV_CLOCK_BOOTTIME	/* monotonic, suspend-awared */
79 };
80 
81 /*
82  * Locking.
83  *
84  * Internal  evdev structures are protected with next locks:
85  * State lock		(s) - Internal state. The data it protects is changed
86  *			      by incoming evdev events and some ioctls.
87  * Client list epoch	(l) - Read access to client list.
88  * Client list lock	(l) - Write access to client list.
89  * Client queue locks	(q) - One lock per client to serialize access to data
90  *			      available through character device node.
91  *
92  * Depending on evdev_register_() suffix evdev can run in following modes:
93  * 1. Internal epoch. evdev_register(). All locks are internal.
94  * 2. External epoch. Evdev expects to be run under input epoch entered by
95  *    parent driver. The mode is enabled with EVDEV_FLAG_EXT_EPOCH flag.
96  * 3. External mutex. evdev_register_mtx(). Evdev uses mutex provided by parent
97  *    driver as both "State lock" and "Client list lock". This mode is
98  *    deprecated as it causes ev_open and ev_close handlers to be called with
99  *    parent driver mutex taken.
100  */
101 #define	INPUT_EPOCH	global_epoch_preempt
102 
103 enum evdev_lock_type
104 {
105 	EV_LOCK_INTERNAL = 0,	/* Internal epoch */
106 	EV_LOCK_MTX,		/* Driver`s mutex */
107 	EV_LOCK_EXT_EPOCH,	/* External epoch */
108 };
109 
110 struct evdev_dev
111 {
112 	char			ev_name[NAMELEN];
113 	char			ev_shortname[NAMELEN];
114 	char			ev_serial[NAMELEN];
115 	struct cdev *		ev_cdev;
116 	int			ev_unit;
117 	enum evdev_lock_type	ev_lock_type;
118 	struct mtx *		ev_state_lock;	/* State lock */
119 	struct mtx		ev_mtx;		/* Internal state lock */
120 	struct sx		ev_list_lock;	/* Client list lock */
121 	struct input_id		ev_id;
122 	struct evdev_client *	ev_grabber;			/* (s) */
123 	size_t			ev_report_size;
124 
125 	/* Supported features: */
126 	bitstr_t		bit_decl(ev_prop_flags, INPUT_PROP_CNT);
127 	bitstr_t		bit_decl(ev_type_flags, EV_CNT);
128 	bitstr_t		bit_decl(ev_key_flags, KEY_CNT);
129 	bitstr_t		bit_decl(ev_rel_flags, REL_CNT);
130 	bitstr_t		bit_decl(ev_abs_flags, ABS_CNT);
131 	bitstr_t		bit_decl(ev_msc_flags, MSC_CNT);
132 	bitstr_t		bit_decl(ev_led_flags, LED_CNT);
133 	bitstr_t		bit_decl(ev_snd_flags, SND_CNT);
134 	bitstr_t		bit_decl(ev_sw_flags, SW_CNT);
135 	struct input_absinfo *	ev_absinfo;			/* (s) */
136 	bitstr_t		bit_decl(ev_flags, EVDEV_FLAG_CNT);
137 
138 	/* Repeat parameters & callout: */
139 	int			ev_rep[REP_CNT];		/* (s) */
140 	struct callout		ev_rep_callout;			/* (s) */
141 	uint16_t		ev_rep_key;			/* (s) */
142 
143 	/* State: */
144 	bitstr_t		bit_decl(ev_key_states, KEY_CNT); /* (s) */
145 	bitstr_t		bit_decl(ev_led_states, LED_CNT); /* (s) */
146 	bitstr_t		bit_decl(ev_snd_states, SND_CNT); /* (s) */
147 	bitstr_t		bit_decl(ev_sw_states, SW_CNT);	/* (s) */
148 	bool			ev_report_opened;		/* (s) */
149 
150 	/* KDB state: */
151 	bool			ev_kdb_active;
152 	bitstr_t		bit_decl(ev_kdb_led_states, LED_CNT);
153 
154 	/* Multitouch protocol type B state: */
155 	struct evdev_mt *	ev_mt;				/* (s) */
156 
157 	/* Counters: */
158 	uint64_t		ev_event_count;			/* (s) */
159 	uint64_t		ev_report_count;		/* (s) */
160 
161 	/* Parent driver callbacks: */
162 	const struct evdev_methods * ev_methods;
163 	void *			ev_softc;
164 
165 	/* Sysctl: */
166 	struct sysctl_ctx_list	ev_sysctl_ctx;
167 
168 	LIST_ENTRY(evdev_dev) ev_link;
169 	CK_SLIST_HEAD(, evdev_client) ev_clients;		/* (l) */
170 };
171 
172 #define	SYSTEM_CONSOLE_LOCK	&Giant
173 
174 #define	EVDEV_LOCK(evdev)		mtx_lock((evdev)->ev_state_lock)
175 #define	EVDEV_UNLOCK(evdev)		mtx_unlock((evdev)->ev_state_lock)
176 #define	EVDEV_LOCK_ASSERT(evdev)	do {				\
177 	if ((evdev)->ev_state_lock != SYSTEM_CONSOLE_LOCK)		\
178 		mtx_assert((evdev)->ev_state_lock, MA_OWNED);		\
179 } while (0)
180 #define	EVDEV_ENTER(evdev)	do {					\
181 	if ((evdev)->ev_lock_type != EV_LOCK_MTX)			\
182 		EVDEV_LOCK(evdev);					\
183 	else								\
184 		EVDEV_LOCK_ASSERT(evdev);				\
185 } while (0)
186 #define	EVDEV_EXIT(evdev)	do {					\
187 	if ((evdev)->ev_lock_type != EV_LOCK_MTX)			\
188 		EVDEV_UNLOCK(evdev);					\
189 } while (0)
190 
191 #define	EVDEV_LIST_LOCK(evdev)	do {					\
192 	if ((evdev)->ev_lock_type == EV_LOCK_MTX)			\
193 		EVDEV_LOCK(evdev);					\
194 	else								\
195 		sx_xlock(&(evdev)->ev_list_lock);			\
196 } while (0)
197 #define	EVDEV_LIST_UNLOCK(evdev)	do {				\
198 	if ((evdev)->ev_lock_type == EV_LOCK_MTX)			\
199 		EVDEV_UNLOCK(evdev);					\
200 	else								\
201 		sx_unlock(&(evdev)->ev_list_lock);			\
202 } while (0)
203 #define	EVDEV_LIST_LOCK_ASSERT(evdev)	do {				\
204 	if ((evdev)->ev_lock_type == EV_LOCK_MTX)			\
205 		EVDEV_LOCK_ASSERT(evdev);				\
206 	else								\
207 		sx_assert(&(evdev)->ev_list_lock, MA_OWNED);		\
208 } while (0)
209 static inline int
210 EVDEV_LIST_LOCK_SIG(struct evdev_dev *evdev)
211 {
212 	if (evdev->ev_lock_type == EV_LOCK_MTX) {
213 		EVDEV_LOCK(evdev);
214 		return (0);
215 	}
216 	return (sx_xlock_sig(&evdev->ev_list_lock));
217 }
218 
219 struct evdev_client
220 {
221 	struct evdev_dev *	ec_evdev;
222 	struct mtx		ec_buffer_mtx;	/* Client queue lock */
223 	size_t			ec_buffer_size;
224 	size_t			ec_buffer_head;		/* (q) */
225 	size_t			ec_buffer_tail;		/* (q) */
226 	size_t			ec_buffer_ready;	/* (q) */
227 	enum evdev_clock_id	ec_clock_id;
228 	struct selinfo		ec_selp;		/* (q) */
229 	struct sigio *		ec_sigio;
230 	bool			ec_async;		/* (q) */
231 	bool			ec_revoked;		/* (l) */
232 	bool			ec_blocked;		/* (q) */
233 	bool			ec_selected;		/* (q) */
234 
235 	CK_SLIST_ENTRY(evdev_client) ec_link;		/* (l) */
236 
237 	struct input_event	ec_buffer[];		/* (q) */
238 };
239 
240 #define	EVDEV_CLIENT_LOCKQ(client)	mtx_lock(&(client)->ec_buffer_mtx)
241 #define	EVDEV_CLIENT_UNLOCKQ(client)	mtx_unlock(&(client)->ec_buffer_mtx)
242 #define EVDEV_CLIENT_LOCKQ_ASSERT(client) \
243     mtx_assert(&(client)->ec_buffer_mtx, MA_OWNED)
244 #define	EVDEV_CLIENT_EMPTYQ(client) \
245     ((client)->ec_buffer_head == (client)->ec_buffer_ready)
246 #define	EVDEV_CLIENT_SIZEQ(client) \
247     (((client)->ec_buffer_ready + (client)->ec_buffer_size - \
248       (client)->ec_buffer_head) % (client)->ec_buffer_size)
249 
250 /* bitstring(3) helper */
251 static inline void
252 bit_change(bitstr_t *bitstr, int bit, int value)
253 {
254 	if (value)
255 		bit_set(bitstr, bit);
256 	else
257 		bit_clear(bitstr, bit);
258 }
259 
260 /* Input device interface: */
261 void evdev_send_event(struct evdev_dev *, uint16_t, uint16_t, int32_t);
262 int evdev_inject_event(struct evdev_dev *, uint16_t, uint16_t, int32_t);
263 int evdev_cdev_create(struct evdev_dev *);
264 int evdev_cdev_destroy(struct evdev_dev *);
265 bool evdev_event_supported(struct evdev_dev *, uint16_t);
266 void evdev_set_abs_bit(struct evdev_dev *, uint16_t);
267 void evdev_set_absinfo(struct evdev_dev *, uint16_t, struct input_absinfo *);
268 void evdev_restore_after_kdb(struct evdev_dev *);
269 
270 /* Client interface: */
271 int evdev_register_client(struct evdev_dev *, struct evdev_client *);
272 void evdev_dispose_client(struct evdev_dev *, struct evdev_client *);
273 int evdev_grab_client(struct evdev_dev *, struct evdev_client *);
274 int evdev_release_client(struct evdev_dev *, struct evdev_client *);
275 void evdev_client_push(struct evdev_client *, uint16_t, uint16_t, int32_t);
276 void evdev_notify_event(struct evdev_client *);
277 void evdev_revoke_client(struct evdev_client *);
278 
279 /* Multitouch related functions: */
280 void evdev_mt_init(struct evdev_dev *);
281 void evdev_mt_free(struct evdev_dev *);
282 void evdev_mt_sync_frame(struct evdev_dev *);
283 int evdev_mt_get_last_slot(struct evdev_dev *);
284 void evdev_mt_set_last_slot(struct evdev_dev *, int);
285 int32_t evdev_mt_get_value(struct evdev_dev *, int, int16_t);
286 void evdev_mt_set_value(struct evdev_dev *, int, int16_t, int32_t);
287 int32_t evdev_mt_reassign_id(struct evdev_dev *, int, int32_t);
288 bool evdev_mt_record_event(struct evdev_dev *, uint16_t, uint16_t, int32_t);
289 
290 /* Utility functions: */
291 void evdev_client_dumpqueue(struct evdev_client *);
292 void evdev_send_nfingers(struct evdev_dev *, int);
293 
294 #endif	/* _DEV_EVDEV_EVDEV_PRIVATE_H */
295