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/interrupt.h> |
18 | #include <linux/input.h> | |
19 | #include <linux/serio.h> | |
181d683d | 20 | #include <linux/i8042.h> |
1da177e4 LT |
21 | #include <linux/libps2.h> |
22 | ||
23 | #define DRIVER_DESC "PS/2 driver library" | |
24 | ||
25 | MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); | |
26 | MODULE_DESCRIPTION("PS/2 driver library"); | |
27 | MODULE_LICENSE("GPL"); | |
28 | ||
1da177e4 | 29 | /* |
c611763d DT |
30 | * ps2_sendbyte() sends a byte to the device and waits for acknowledge. |
31 | * It doesn't handle retransmission, though it could - because if there | |
32 | * is a need for retransmissions device has to be replaced anyway. | |
1da177e4 | 33 | * |
c611763d | 34 | * ps2_sendbyte() can only be called from a process context. |
1da177e4 LT |
35 | */ |
36 | ||
37 | int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout) | |
38 | { | |
39 | serio_pause_rx(ps2dev->serio); | |
40 | ps2dev->nak = 1; | |
41 | ps2dev->flags |= PS2_FLAG_ACK; | |
42 | serio_continue_rx(ps2dev->serio); | |
43 | ||
44 | if (serio_write(ps2dev->serio, byte) == 0) | |
45 | wait_event_timeout(ps2dev->wait, | |
46 | !(ps2dev->flags & PS2_FLAG_ACK), | |
47 | msecs_to_jiffies(timeout)); | |
48 | ||
49 | serio_pause_rx(ps2dev->serio); | |
50 | ps2dev->flags &= ~PS2_FLAG_ACK; | |
51 | serio_continue_rx(ps2dev->serio); | |
52 | ||
53 | return -ps2dev->nak; | |
54 | } | |
5206c0d5 | 55 | EXPORT_SYMBOL(ps2_sendbyte); |
1da177e4 | 56 | |
181d683d DT |
57 | void ps2_begin_command(struct ps2dev *ps2dev) |
58 | { | |
40974618 | 59 | struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex; |
181d683d | 60 | |
40974618 | 61 | mutex_lock(m); |
181d683d DT |
62 | } |
63 | EXPORT_SYMBOL(ps2_begin_command); | |
64 | ||
65 | void ps2_end_command(struct ps2dev *ps2dev) | |
66 | { | |
40974618 | 67 | struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex; |
181d683d | 68 | |
40974618 | 69 | mutex_unlock(m); |
181d683d DT |
70 | } |
71 | EXPORT_SYMBOL(ps2_end_command); | |
72 | ||
c611763d DT |
73 | /* |
74 | * ps2_drain() waits for device to transmit requested number of bytes | |
75 | * and discards them. | |
76 | */ | |
77 | ||
78 | void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout) | |
79 | { | |
80 | if (maxbytes > sizeof(ps2dev->cmdbuf)) { | |
81 | WARN_ON(1); | |
82 | maxbytes = sizeof(ps2dev->cmdbuf); | |
83 | } | |
84 | ||
181d683d | 85 | ps2_begin_command(ps2dev); |
c611763d DT |
86 | |
87 | serio_pause_rx(ps2dev->serio); | |
88 | ps2dev->flags = PS2_FLAG_CMD; | |
89 | ps2dev->cmdcnt = maxbytes; | |
90 | serio_continue_rx(ps2dev->serio); | |
91 | ||
92 | wait_event_timeout(ps2dev->wait, | |
93 | !(ps2dev->flags & PS2_FLAG_CMD), | |
94 | msecs_to_jiffies(timeout)); | |
181d683d DT |
95 | |
96 | ps2_end_command(ps2dev); | |
c611763d | 97 | } |
5206c0d5 | 98 | EXPORT_SYMBOL(ps2_drain); |
c611763d | 99 | |
905ab9d1 DT |
100 | /* |
101 | * ps2_is_keyboard_id() checks received ID byte against the list of | |
102 | * known keyboard IDs. | |
103 | */ | |
104 | ||
9807879b | 105 | int ps2_is_keyboard_id(char id_byte) |
905ab9d1 | 106 | { |
c5a69d57 | 107 | static const char keyboard_ids[] = { |
905ab9d1 DT |
108 | 0xab, /* Regular keyboards */ |
109 | 0xac, /* NCD Sun keyboard */ | |
110 | 0x2b, /* Trust keyboard, translated */ | |
111 | 0x5d, /* Trust keyboard */ | |
112 | 0x60, /* NMB SGI keyboard, translated */ | |
113 | 0x47, /* NMB SGI keyboard */ | |
114 | }; | |
115 | ||
116 | return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL; | |
117 | } | |
5206c0d5 | 118 | EXPORT_SYMBOL(ps2_is_keyboard_id); |
905ab9d1 DT |
119 | |
120 | /* | |
121 | * ps2_adjust_timeout() is called after receiving 1st byte of command | |
122 | * response and tries to reduce remaining timeout to speed up command | |
123 | * completion. | |
124 | */ | |
125 | ||
126 | static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout) | |
127 | { | |
128 | switch (command) { | |
129 | case PS2_CMD_RESET_BAT: | |
130 | /* | |
131 | * Device has sent the first response byte after | |
132 | * reset command, reset is thus done, so we can | |
133 | * shorten the timeout. | |
134 | * The next byte will come soon (keyboard) or not | |
135 | * at all (mouse). | |
136 | */ | |
137 | if (timeout > msecs_to_jiffies(100)) | |
138 | timeout = msecs_to_jiffies(100); | |
139 | break; | |
140 | ||
141 | case PS2_CMD_GETID: | |
9807879b DT |
142 | /* |
143 | * Microsoft Natural Elite keyboard responds to | |
144 | * the GET ID command as it were a mouse, with | |
145 | * a single byte. Fail the command so atkbd will | |
146 | * use alternative probe to detect it. | |
147 | */ | |
148 | if (ps2dev->cmdbuf[1] == 0xaa) { | |
149 | serio_pause_rx(ps2dev->serio); | |
150 | ps2dev->flags = 0; | |
151 | serio_continue_rx(ps2dev->serio); | |
152 | timeout = 0; | |
153 | } | |
154 | ||
905ab9d1 DT |
155 | /* |
156 | * If device behind the port is not a keyboard there | |
157 | * won't be 2nd byte of ID response. | |
158 | */ | |
159 | if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) { | |
160 | serio_pause_rx(ps2dev->serio); | |
161 | ps2dev->flags = ps2dev->cmdcnt = 0; | |
162 | serio_continue_rx(ps2dev->serio); | |
163 | timeout = 0; | |
164 | } | |
165 | break; | |
166 | ||
167 | default: | |
168 | break; | |
169 | } | |
170 | ||
171 | return timeout; | |
172 | } | |
173 | ||
1da177e4 LT |
174 | /* |
175 | * ps2_command() sends a command and its parameters to the mouse, | |
176 | * then waits for the response and puts it in the param array. | |
177 | * | |
178 | * ps2_command() can only be called from a process context | |
179 | */ | |
180 | ||
fc69f4a6 | 181 | int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) |
1da177e4 LT |
182 | { |
183 | int timeout; | |
184 | int send = (command >> 12) & 0xf; | |
185 | int receive = (command >> 8) & 0xf; | |
186 | int rc = -1; | |
187 | int i; | |
188 | ||
c611763d DT |
189 | if (receive > sizeof(ps2dev->cmdbuf)) { |
190 | WARN_ON(1); | |
191 | return -1; | |
192 | } | |
193 | ||
95349fe8 DT |
194 | if (send && !param) { |
195 | WARN_ON(1); | |
196 | return -1; | |
197 | } | |
198 | ||
1da177e4 LT |
199 | serio_pause_rx(ps2dev->serio); |
200 | ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; | |
201 | ps2dev->cmdcnt = receive; | |
202 | if (receive && param) | |
203 | for (i = 0; i < receive; i++) | |
204 | ps2dev->cmdbuf[(receive - 1) - i] = param[i]; | |
205 | serio_continue_rx(ps2dev->serio); | |
206 | ||
207 | /* | |
208 | * Some devices (Synaptics) peform the reset before | |
209 | * ACKing the reset command, and so it can take a long | |
83ae417b | 210 | * time before the ACK arrives. |
1da177e4 | 211 | */ |
c611763d | 212 | if (ps2_sendbyte(ps2dev, command & 0xff, |
218c1f76 DV |
213 | command == PS2_CMD_RESET_BAT ? 1000 : 200)) { |
214 | serio_pause_rx(ps2dev->serio); | |
215 | goto out_reset_flags; | |
216 | } | |
1da177e4 | 217 | |
218c1f76 DV |
218 | for (i = 0; i < send; i++) { |
219 | if (ps2_sendbyte(ps2dev, param[i], 200)) { | |
220 | serio_pause_rx(ps2dev->serio); | |
221 | goto out_reset_flags; | |
222 | } | |
223 | } | |
1da177e4 LT |
224 | |
225 | /* | |
226 | * The reset command takes a long time to execute. | |
227 | */ | |
228 | timeout = msecs_to_jiffies(command == PS2_CMD_RESET_BAT ? 4000 : 500); | |
229 | ||
230 | timeout = wait_event_timeout(ps2dev->wait, | |
231 | !(ps2dev->flags & PS2_FLAG_CMD1), timeout); | |
232 | ||
a3ce6ea4 | 233 | if (ps2dev->cmdcnt && !(ps2dev->flags & PS2_FLAG_CMD1)) { |
1da177e4 | 234 | |
905ab9d1 | 235 | timeout = ps2_adjust_timeout(ps2dev, command, timeout); |
1da177e4 LT |
236 | wait_event_timeout(ps2dev->wait, |
237 | !(ps2dev->flags & PS2_FLAG_CMD), timeout); | |
238 | } | |
239 | ||
218c1f76 DV |
240 | serio_pause_rx(ps2dev->serio); |
241 | ||
1da177e4 LT |
242 | if (param) |
243 | for (i = 0; i < receive; i++) | |
244 | param[i] = ps2dev->cmdbuf[(receive - 1) - i]; | |
245 | ||
246 | if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) | |
218c1f76 | 247 | goto out_reset_flags; |
1da177e4 LT |
248 | |
249 | rc = 0; | |
250 | ||
218c1f76 | 251 | out_reset_flags: |
1da177e4 LT |
252 | ps2dev->flags = 0; |
253 | serio_continue_rx(ps2dev->serio); | |
254 | ||
fc69f4a6 TL |
255 | return rc; |
256 | } | |
257 | EXPORT_SYMBOL(__ps2_command); | |
258 | ||
259 | int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) | |
260 | { | |
261 | int rc; | |
262 | ||
181d683d | 263 | ps2_begin_command(ps2dev); |
fc69f4a6 | 264 | rc = __ps2_command(ps2dev, param, command); |
181d683d | 265 | ps2_end_command(ps2dev); |
fc69f4a6 | 266 | |
1da177e4 LT |
267 | return rc; |
268 | } | |
5206c0d5 | 269 | EXPORT_SYMBOL(ps2_command); |
1da177e4 | 270 | |
1da177e4 LT |
271 | /* |
272 | * ps2_init() initializes ps2dev structure | |
273 | */ | |
274 | ||
275 | void ps2_init(struct ps2dev *ps2dev, struct serio *serio) | |
276 | { | |
c4e32e9f | 277 | mutex_init(&ps2dev->cmd_mutex); |
88aa0103 | 278 | lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth); |
1da177e4 LT |
279 | init_waitqueue_head(&ps2dev->wait); |
280 | ps2dev->serio = serio; | |
281 | } | |
5206c0d5 | 282 | EXPORT_SYMBOL(ps2_init); |
1da177e4 LT |
283 | |
284 | /* | |
285 | * ps2_handle_ack() is supposed to be used in interrupt handler | |
286 | * to properly process ACK/NAK of a command from a PS/2 device. | |
287 | */ | |
288 | ||
289 | int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data) | |
290 | { | |
291 | switch (data) { | |
292 | case PS2_RET_ACK: | |
293 | ps2dev->nak = 0; | |
294 | break; | |
295 | ||
296 | case PS2_RET_NAK: | |
a2d781fc DT |
297 | ps2dev->flags |= PS2_FLAG_NAK; |
298 | ps2dev->nak = PS2_RET_NAK; | |
1da177e4 LT |
299 | break; |
300 | ||
a2d781fc DT |
301 | case PS2_RET_ERR: |
302 | if (ps2dev->flags & PS2_FLAG_NAK) { | |
303 | ps2dev->flags &= ~PS2_FLAG_NAK; | |
304 | ps2dev->nak = PS2_RET_ERR; | |
305 | break; | |
306 | } | |
307 | ||
1da177e4 LT |
308 | /* |
309 | * Workaround for mice which don't ACK the Get ID command. | |
310 | * These are valid mouse IDs that we recognize. | |
311 | */ | |
312 | case 0x00: | |
313 | case 0x03: | |
314 | case 0x04: | |
315 | if (ps2dev->flags & PS2_FLAG_WAITID) { | |
316 | ps2dev->nak = 0; | |
317 | break; | |
318 | } | |
319 | /* Fall through */ | |
320 | default: | |
321 | return 0; | |
322 | } | |
323 | ||
324 | ||
a2d781fc DT |
325 | if (!ps2dev->nak) { |
326 | ps2dev->flags &= ~PS2_FLAG_NAK; | |
327 | if (ps2dev->cmdcnt) | |
328 | ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; | |
329 | } | |
1da177e4 LT |
330 | |
331 | ps2dev->flags &= ~PS2_FLAG_ACK; | |
332 | wake_up(&ps2dev->wait); | |
333 | ||
334 | if (data != PS2_RET_ACK) | |
335 | ps2_handle_response(ps2dev, data); | |
336 | ||
337 | return 1; | |
338 | } | |
5206c0d5 | 339 | EXPORT_SYMBOL(ps2_handle_ack); |
1da177e4 LT |
340 | |
341 | /* | |
342 | * ps2_handle_response() is supposed to be used in interrupt handler | |
343 | * to properly store device's response to a command and notify process | |
344 | * waiting for completion of the command. | |
345 | */ | |
346 | ||
347 | int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data) | |
348 | { | |
349 | if (ps2dev->cmdcnt) | |
350 | ps2dev->cmdbuf[--ps2dev->cmdcnt] = data; | |
351 | ||
352 | if (ps2dev->flags & PS2_FLAG_CMD1) { | |
353 | ps2dev->flags &= ~PS2_FLAG_CMD1; | |
354 | if (ps2dev->cmdcnt) | |
355 | wake_up(&ps2dev->wait); | |
356 | } | |
357 | ||
358 | if (!ps2dev->cmdcnt) { | |
359 | ps2dev->flags &= ~PS2_FLAG_CMD; | |
360 | wake_up(&ps2dev->wait); | |
361 | } | |
362 | ||
363 | return 1; | |
364 | } | |
5206c0d5 | 365 | EXPORT_SYMBOL(ps2_handle_response); |
1da177e4 LT |
366 | |
367 | void ps2_cmd_aborted(struct ps2dev *ps2dev) | |
368 | { | |
369 | if (ps2dev->flags & PS2_FLAG_ACK) | |
370 | ps2dev->nak = 1; | |
371 | ||
372 | if (ps2dev->flags & (PS2_FLAG_ACK | PS2_FLAG_CMD)) | |
373 | wake_up(&ps2dev->wait); | |
374 | ||
a2d781fc DT |
375 | /* reset all flags except last nack */ |
376 | ps2dev->flags &= PS2_FLAG_NAK; | |
1da177e4 | 377 | } |
5206c0d5 | 378 | EXPORT_SYMBOL(ps2_cmd_aborted); |