Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * PS/2 driver library | |
3 | * | |
4 | * Copyright (c) 1999-2002 Vojtech Pavlik | |
5 | * Copyright (c) 2004 Dmitry Torokhov | |
6 | */ | |
7 | ||
8 | /* | |
9 | * This program is free software; you can redistribute it and/or modify it | |
10 | * under the terms of the GNU General Public License version 2 as published by | |
11 | * the Free Software Foundation. | |
12 | */ | |
13 | ||
14 | #include <linux/delay.h> | |
15 | #include <linux/module.h> | |
d43c36dc | 16 | #include <linux/sched.h> |
1da177e4 LT |
17 | #include <linux/slab.h> |
18 | #include <linux/interrupt.h> | |
19 | #include <linux/input.h> | |
20 | #include <linux/serio.h> | |
181d683d | 21 | #include <linux/i8042.h> |
1da177e4 LT |
22 | #include <linux/init.h> |
23 | #include <linux/libps2.h> | |
24 | ||
25 | #define DRIVER_DESC "PS/2 driver library" | |
26 | ||
27 | MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); | |
28 | MODULE_DESCRIPTION("PS/2 driver library"); | |
29 | MODULE_LICENSE("GPL"); | |
30 | ||
1da177e4 | 31 | /* |
c611763d DT |
32 | * ps2_sendbyte() sends a byte to the device and waits for acknowledge. |
33 | * It doesn't handle retransmission, though it could - because if there | |
34 | * is a need for retransmissions device has to be replaced anyway. | |
1da177e4 | 35 | * |
c611763d | 36 | * ps2_sendbyte() can only be called from a process context. |
1da177e4 LT |
37 | */ |
38 | ||
39 | int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout) | |
40 | { | |
41 | serio_pause_rx(ps2dev->serio); | |
42 | ps2dev->nak = 1; | |
43 | ps2dev->flags |= PS2_FLAG_ACK; | |
44 | serio_continue_rx(ps2dev->serio); | |
45 | ||
46 | if (serio_write(ps2dev->serio, byte) == 0) | |
47 | wait_event_timeout(ps2dev->wait, | |
48 | !(ps2dev->flags & PS2_FLAG_ACK), | |
49 | msecs_to_jiffies(timeout)); | |
50 | ||
51 | serio_pause_rx(ps2dev->serio); | |
52 | ps2dev->flags &= ~PS2_FLAG_ACK; | |
53 | serio_continue_rx(ps2dev->serio); | |
54 | ||
55 | return -ps2dev->nak; | |
56 | } | |
5206c0d5 | 57 | EXPORT_SYMBOL(ps2_sendbyte); |
1da177e4 | 58 | |
181d683d DT |
59 | void ps2_begin_command(struct ps2dev *ps2dev) |
60 | { | |
61 | mutex_lock(&ps2dev->cmd_mutex); | |
62 | ||
63 | if (i8042_check_port_owner(ps2dev->serio)) | |
64 | i8042_lock_chip(); | |
65 | } | |
66 | EXPORT_SYMBOL(ps2_begin_command); | |
67 | ||
68 | void ps2_end_command(struct ps2dev *ps2dev) | |
69 | { | |
70 | if (i8042_check_port_owner(ps2dev->serio)) | |
71 | i8042_unlock_chip(); | |
72 | ||
73 | mutex_unlock(&ps2dev->cmd_mutex); | |
74 | } | |
75 | EXPORT_SYMBOL(ps2_end_command); | |
76 | ||
c611763d DT |
77 | /* |
78 | * ps2_drain() waits for device to transmit requested number of bytes | |
79 | * and discards them. | |
80 | */ | |
81 | ||
82 | void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout) | |
83 | { | |
84 | if (maxbytes > sizeof(ps2dev->cmdbuf)) { | |
85 | WARN_ON(1); | |
86 | maxbytes = sizeof(ps2dev->cmdbuf); | |
87 | } | |
88 | ||
181d683d | 89 | ps2_begin_command(ps2dev); |
c611763d DT |
90 | |
91 | serio_pause_rx(ps2dev->serio); | |
92 | ps2dev->flags = PS2_FLAG_CMD; | |
93 | ps2dev->cmdcnt = maxbytes; | |
94 | serio_continue_rx(ps2dev->serio); | |
95 | ||
96 | wait_event_timeout(ps2dev->wait, | |
97 | !(ps2dev->flags & PS2_FLAG_CMD), | |
98 | msecs_to_jiffies(timeout)); | |
181d683d DT |
99 | |
100 | ps2_end_command(ps2dev); | |
c611763d | 101 | } |
5206c0d5 | 102 | EXPORT_SYMBOL(ps2_drain); |
c611763d | 103 | |
905ab9d1 DT |
104 | /* |
105 | * ps2_is_keyboard_id() checks received ID byte against the list of | |
106 | * known keyboard IDs. | |
107 | */ | |
108 | ||
9807879b | 109 | int ps2_is_keyboard_id(char id_byte) |
905ab9d1 | 110 | { |
c5a69d57 | 111 | static const char keyboard_ids[] = { |
905ab9d1 DT |
112 | 0xab, /* Regular keyboards */ |
113 | 0xac, /* NCD Sun keyboard */ | |
114 | 0x2b, /* Trust keyboard, translated */ | |
115 | 0x5d, /* Trust keyboard */ | |
116 | 0x60, /* NMB SGI keyboard, translated */ | |
117 | 0x47, /* NMB SGI keyboard */ | |
118 | }; | |
119 | ||
120 | return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL; | |
121 | } | |
5206c0d5 | 122 | EXPORT_SYMBOL(ps2_is_keyboard_id); |
905ab9d1 DT |
123 | |
124 | /* | |
125 | * ps2_adjust_timeout() is called after receiving 1st byte of command | |
126 | * response and tries to reduce remaining timeout to speed up command | |
127 | * completion. | |
128 | */ | |
129 | ||
130 | static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout) | |
131 | { | |
132 | switch (command) { | |
133 | case PS2_CMD_RESET_BAT: | |
134 | /* | |
135 | * Device has sent the first response byte after | |
136 | * reset command, reset is thus done, so we can | |
137 | * shorten the timeout. | |
138 | * The next byte will come soon (keyboard) or not | |
139 | * at all (mouse). | |
140 | */ | |
141 | if (timeout > msecs_to_jiffies(100)) | |
142 | timeout = msecs_to_jiffies(100); | |
143 | break; | |
144 | ||
145 | case PS2_CMD_GETID: | |
9807879b DT |
146 | /* |
147 | * Microsoft Natural Elite keyboard responds to | |
148 | * the GET ID command as it were a mouse, with | |
149 | * a single byte. Fail the command so atkbd will | |
150 | * use alternative probe to detect it. | |
151 | */ | |
152 | if (ps2dev->cmdbuf[1] == 0xaa) { | |
153 | serio_pause_rx(ps2dev->serio); | |
154 | ps2dev->flags = 0; | |
155 | serio_continue_rx(ps2dev->serio); | |
156 | timeout = 0; | |
157 | } | |
158 | ||
905ab9d1 DT |
159 | /* |
160 | * If device behind the port is not a keyboard there | |
161 | * won't be 2nd byte of ID response. | |
162 | */ | |
163 | if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) { | |
164 | serio_pause_rx(ps2dev->serio); | |
165 | ps2dev->flags = ps2dev->cmdcnt = 0; | |
166 | serio_continue_rx(ps2dev->serio); | |
167 | timeout = 0; | |
168 | } | |
169 | break; | |
170 | ||
171 | default: | |
172 | break; | |
173 | } | |
174 | ||
175 | return timeout; | |
176 | } | |
177 | ||
1da177e4 LT |
178 | /* |
179 | * ps2_command() sends a command and its parameters to the mouse, | |
180 | * then waits for the response and puts it in the param array. | |
181 | * | |
182 | * ps2_command() can only be called from a process context | |
183 | */ | |
184 | ||
fc69f4a6 | 185 | int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) |
1da177e4 LT |
186 | { |
187 | int timeout; | |
188 | int send = (command >> 12) & 0xf; | |
189 | int receive = (command >> 8) & 0xf; | |
190 | int rc = -1; | |
191 | int i; | |
192 | ||
c611763d DT |
193 | if (receive > sizeof(ps2dev->cmdbuf)) { |
194 | WARN_ON(1); | |
195 | return -1; | |
196 | } | |
197 | ||
95349fe8 DT |
198 | if (send && !param) { |
199 | WARN_ON(1); | |
200 | return -1; | |
201 | } | |
202 | ||
1da177e4 LT |
203 | serio_pause_rx(ps2dev->serio); |
204 | ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; | |
205 | ps2dev->cmdcnt = receive; | |
206 | if (receive && param) | |
207 | for (i = 0; i < receive; i++) | |
208 | ps2dev->cmdbuf[(receive - 1) - i] = param[i]; | |
209 | serio_continue_rx(ps2dev->serio); | |
210 | ||
211 | /* | |
212 | * Some devices (Synaptics) peform the reset before | |
213 | * ACKing the reset command, and so it can take a long | |
214 | * time before the ACK arrrives. | |
215 | */ | |
c611763d DT |
216 | if (ps2_sendbyte(ps2dev, command & 0xff, |
217 | command == PS2_CMD_RESET_BAT ? 1000 : 200)) | |
218 | goto out; | |
1da177e4 LT |
219 | |
220 | for (i = 0; i < send; i++) | |
221 | if (ps2_sendbyte(ps2dev, param[i], 200)) | |
222 | goto out; | |
223 | ||
224 | /* | |
225 | * The reset command takes a long time to execute. | |
226 | */ | |
227 | timeout = msecs_to_jiffies(command == PS2_CMD_RESET_BAT ? 4000 : 500); | |
228 | ||
229 | timeout = wait_event_timeout(ps2dev->wait, | |
230 | !(ps2dev->flags & PS2_FLAG_CMD1), timeout); | |
231 | ||
a3ce6ea4 | 232 | if (ps2dev->cmdcnt && !(ps2dev->flags & PS2_FLAG_CMD1)) { |
1da177e4 | 233 | |
905ab9d1 | 234 | timeout = ps2_adjust_timeout(ps2dev, command, timeout); |
1da177e4 LT |
235 | wait_event_timeout(ps2dev->wait, |
236 | !(ps2dev->flags & PS2_FLAG_CMD), timeout); | |
237 | } | |
238 | ||
239 | if (param) | |
240 | for (i = 0; i < receive; i++) | |
241 | param[i] = ps2dev->cmdbuf[(receive - 1) - i]; | |
242 | ||
243 | if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) | |
244 | goto out; | |
245 | ||
246 | rc = 0; | |
247 | ||
905ab9d1 | 248 | out: |
1da177e4 LT |
249 | serio_pause_rx(ps2dev->serio); |
250 | ps2dev->flags = 0; | |
251 | serio_continue_rx(ps2dev->serio); | |
252 | ||
fc69f4a6 TL |
253 | return rc; |
254 | } | |
255 | EXPORT_SYMBOL(__ps2_command); | |
256 | ||
257 | int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) | |
258 | { | |
259 | int rc; | |
260 | ||
181d683d | 261 | ps2_begin_command(ps2dev); |
fc69f4a6 | 262 | rc = __ps2_command(ps2dev, param, command); |
181d683d | 263 | ps2_end_command(ps2dev); |
fc69f4a6 | 264 | |
1da177e4 LT |
265 | return rc; |
266 | } | |
5206c0d5 | 267 | EXPORT_SYMBOL(ps2_command); |
1da177e4 | 268 | |
1da177e4 LT |
269 | /* |
270 | * ps2_init() initializes ps2dev structure | |
271 | */ | |
272 | ||
273 | void ps2_init(struct ps2dev *ps2dev, struct serio *serio) | |
274 | { | |
c4e32e9f | 275 | mutex_init(&ps2dev->cmd_mutex); |
88aa0103 | 276 | lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth); |
1da177e4 LT |
277 | init_waitqueue_head(&ps2dev->wait); |
278 | ps2dev->serio = serio; | |
279 | } | |
5206c0d5 | 280 | EXPORT_SYMBOL(ps2_init); |
1da177e4 LT |
281 | |
282 | /* | |
283 | * ps2_handle_ack() is supposed to be used in interrupt handler | |
284 | * to properly process ACK/NAK of a command from a PS/2 device. | |
285 | */ | |
286 | ||
287 | int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data) | |
288 | { | |
289 | switch (data) { | |
290 | case PS2_RET_ACK: | |
291 | ps2dev->nak = 0; | |
292 | break; | |
293 | ||
294 | case PS2_RET_NAK: | |
a2d781fc DT |
295 | ps2dev->flags |= PS2_FLAG_NAK; |
296 | ps2dev->nak = PS2_RET_NAK; | |
1da177e4 LT |
297 | break; |
298 | ||
a2d781fc DT |
299 | case PS2_RET_ERR: |
300 | if (ps2dev->flags & PS2_FLAG_NAK) { | |
301 | ps2dev->flags &= ~PS2_FLAG_NAK; | |
302 | ps2dev->nak = PS2_RET_ERR; | |
303 | break; | |
304 | } | |
305 | ||
1da177e4 LT |
306 | /* |
307 | * Workaround for mice which don't ACK the Get ID command. | |
308 | * These are valid mouse IDs that we recognize. | |
309 | */ | |
310 | case 0x00: | |
311 | case 0x03: | |
312 | case 0x04: | |
313 | if (ps2dev->flags & PS2_FLAG_WAITID) { | |
314 | ps2dev->nak = 0; | |
315 | break; | |
316 | } | |
317 | /* Fall through */ | |
318 | default: | |
319 | return 0; | |
320 | } | |
321 | ||
322 | ||
a2d781fc DT |
323 | if (!ps2dev->nak) { |
324 | ps2dev->flags &= ~PS2_FLAG_NAK; | |
325 | if (ps2dev->cmdcnt) | |
326 | ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; | |
327 | } | |
1da177e4 LT |
328 | |
329 | ps2dev->flags &= ~PS2_FLAG_ACK; | |
330 | wake_up(&ps2dev->wait); | |
331 | ||
332 | if (data != PS2_RET_ACK) | |
333 | ps2_handle_response(ps2dev, data); | |
334 | ||
335 | return 1; | |
336 | } | |
5206c0d5 | 337 | EXPORT_SYMBOL(ps2_handle_ack); |
1da177e4 LT |
338 | |
339 | /* | |
340 | * ps2_handle_response() is supposed to be used in interrupt handler | |
341 | * to properly store device's response to a command and notify process | |
342 | * waiting for completion of the command. | |
343 | */ | |
344 | ||
345 | int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data) | |
346 | { | |
347 | if (ps2dev->cmdcnt) | |
348 | ps2dev->cmdbuf[--ps2dev->cmdcnt] = data; | |
349 | ||
350 | if (ps2dev->flags & PS2_FLAG_CMD1) { | |
351 | ps2dev->flags &= ~PS2_FLAG_CMD1; | |
352 | if (ps2dev->cmdcnt) | |
353 | wake_up(&ps2dev->wait); | |
354 | } | |
355 | ||
356 | if (!ps2dev->cmdcnt) { | |
357 | ps2dev->flags &= ~PS2_FLAG_CMD; | |
358 | wake_up(&ps2dev->wait); | |
359 | } | |
360 | ||
361 | return 1; | |
362 | } | |
5206c0d5 | 363 | EXPORT_SYMBOL(ps2_handle_response); |
1da177e4 LT |
364 | |
365 | void ps2_cmd_aborted(struct ps2dev *ps2dev) | |
366 | { | |
367 | if (ps2dev->flags & PS2_FLAG_ACK) | |
368 | ps2dev->nak = 1; | |
369 | ||
370 | if (ps2dev->flags & (PS2_FLAG_ACK | PS2_FLAG_CMD)) | |
371 | wake_up(&ps2dev->wait); | |
372 | ||
a2d781fc DT |
373 | /* reset all flags except last nack */ |
374 | ps2dev->flags &= PS2_FLAG_NAK; | |
1da177e4 | 375 | } |
5206c0d5 | 376 | EXPORT_SYMBOL(ps2_cmd_aborted); |