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 | { | |
59 | mutex_lock(&ps2dev->cmd_mutex); | |
60 | ||
61 | if (i8042_check_port_owner(ps2dev->serio)) | |
62 | i8042_lock_chip(); | |
63 | } | |
64 | EXPORT_SYMBOL(ps2_begin_command); | |
65 | ||
66 | void ps2_end_command(struct ps2dev *ps2dev) | |
67 | { | |
68 | if (i8042_check_port_owner(ps2dev->serio)) | |
69 | i8042_unlock_chip(); | |
70 | ||
71 | mutex_unlock(&ps2dev->cmd_mutex); | |
72 | } | |
73 | EXPORT_SYMBOL(ps2_end_command); | |
74 | ||
c611763d DT |
75 | /* |
76 | * ps2_drain() waits for device to transmit requested number of bytes | |
77 | * and discards them. | |
78 | */ | |
79 | ||
80 | void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout) | |
81 | { | |
82 | if (maxbytes > sizeof(ps2dev->cmdbuf)) { | |
83 | WARN_ON(1); | |
84 | maxbytes = sizeof(ps2dev->cmdbuf); | |
85 | } | |
86 | ||
181d683d | 87 | ps2_begin_command(ps2dev); |
c611763d DT |
88 | |
89 | serio_pause_rx(ps2dev->serio); | |
90 | ps2dev->flags = PS2_FLAG_CMD; | |
91 | ps2dev->cmdcnt = maxbytes; | |
92 | serio_continue_rx(ps2dev->serio); | |
93 | ||
94 | wait_event_timeout(ps2dev->wait, | |
95 | !(ps2dev->flags & PS2_FLAG_CMD), | |
96 | msecs_to_jiffies(timeout)); | |
181d683d DT |
97 | |
98 | ps2_end_command(ps2dev); | |
c611763d | 99 | } |
5206c0d5 | 100 | EXPORT_SYMBOL(ps2_drain); |
c611763d | 101 | |
905ab9d1 DT |
102 | /* |
103 | * ps2_is_keyboard_id() checks received ID byte against the list of | |
104 | * known keyboard IDs. | |
105 | */ | |
106 | ||
9807879b | 107 | int ps2_is_keyboard_id(char id_byte) |
905ab9d1 | 108 | { |
c5a69d57 | 109 | static const char keyboard_ids[] = { |
905ab9d1 DT |
110 | 0xab, /* Regular keyboards */ |
111 | 0xac, /* NCD Sun keyboard */ | |
112 | 0x2b, /* Trust keyboard, translated */ | |
113 | 0x5d, /* Trust keyboard */ | |
114 | 0x60, /* NMB SGI keyboard, translated */ | |
115 | 0x47, /* NMB SGI keyboard */ | |
116 | }; | |
117 | ||
118 | return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL; | |
119 | } | |
5206c0d5 | 120 | EXPORT_SYMBOL(ps2_is_keyboard_id); |
905ab9d1 DT |
121 | |
122 | /* | |
123 | * ps2_adjust_timeout() is called after receiving 1st byte of command | |
124 | * response and tries to reduce remaining timeout to speed up command | |
125 | * completion. | |
126 | */ | |
127 | ||
128 | static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout) | |
129 | { | |
130 | switch (command) { | |
131 | case PS2_CMD_RESET_BAT: | |
132 | /* | |
133 | * Device has sent the first response byte after | |
134 | * reset command, reset is thus done, so we can | |
135 | * shorten the timeout. | |
136 | * The next byte will come soon (keyboard) or not | |
137 | * at all (mouse). | |
138 | */ | |
139 | if (timeout > msecs_to_jiffies(100)) | |
140 | timeout = msecs_to_jiffies(100); | |
141 | break; | |
142 | ||
143 | case PS2_CMD_GETID: | |
9807879b DT |
144 | /* |
145 | * Microsoft Natural Elite keyboard responds to | |
146 | * the GET ID command as it were a mouse, with | |
147 | * a single byte. Fail the command so atkbd will | |
148 | * use alternative probe to detect it. | |
149 | */ | |
150 | if (ps2dev->cmdbuf[1] == 0xaa) { | |
151 | serio_pause_rx(ps2dev->serio); | |
152 | ps2dev->flags = 0; | |
153 | serio_continue_rx(ps2dev->serio); | |
154 | timeout = 0; | |
155 | } | |
156 | ||
905ab9d1 DT |
157 | /* |
158 | * If device behind the port is not a keyboard there | |
159 | * won't be 2nd byte of ID response. | |
160 | */ | |
161 | if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) { | |
162 | serio_pause_rx(ps2dev->serio); | |
163 | ps2dev->flags = ps2dev->cmdcnt = 0; | |
164 | serio_continue_rx(ps2dev->serio); | |
165 | timeout = 0; | |
166 | } | |
167 | break; | |
168 | ||
169 | default: | |
170 | break; | |
171 | } | |
172 | ||
173 | return timeout; | |
174 | } | |
175 | ||
1da177e4 LT |
176 | /* |
177 | * ps2_command() sends a command and its parameters to the mouse, | |
178 | * then waits for the response and puts it in the param array. | |
179 | * | |
180 | * ps2_command() can only be called from a process context | |
181 | */ | |
182 | ||
fc69f4a6 | 183 | int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) |
1da177e4 LT |
184 | { |
185 | int timeout; | |
186 | int send = (command >> 12) & 0xf; | |
187 | int receive = (command >> 8) & 0xf; | |
188 | int rc = -1; | |
189 | int i; | |
190 | ||
c611763d DT |
191 | if (receive > sizeof(ps2dev->cmdbuf)) { |
192 | WARN_ON(1); | |
193 | return -1; | |
194 | } | |
195 | ||
95349fe8 DT |
196 | if (send && !param) { |
197 | WARN_ON(1); | |
198 | return -1; | |
199 | } | |
200 | ||
1da177e4 LT |
201 | serio_pause_rx(ps2dev->serio); |
202 | ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; | |
203 | ps2dev->cmdcnt = receive; | |
204 | if (receive && param) | |
205 | for (i = 0; i < receive; i++) | |
206 | ps2dev->cmdbuf[(receive - 1) - i] = param[i]; | |
207 | serio_continue_rx(ps2dev->serio); | |
208 | ||
209 | /* | |
210 | * Some devices (Synaptics) peform the reset before | |
211 | * ACKing the reset command, and so it can take a long | |
83ae417b | 212 | * time before the ACK arrives. |
1da177e4 | 213 | */ |
c611763d | 214 | if (ps2_sendbyte(ps2dev, command & 0xff, |
218c1f76 DV |
215 | command == PS2_CMD_RESET_BAT ? 1000 : 200)) { |
216 | serio_pause_rx(ps2dev->serio); | |
217 | goto out_reset_flags; | |
218 | } | |
1da177e4 | 219 | |
218c1f76 DV |
220 | for (i = 0; i < send; i++) { |
221 | if (ps2_sendbyte(ps2dev, param[i], 200)) { | |
222 | serio_pause_rx(ps2dev->serio); | |
223 | goto out_reset_flags; | |
224 | } | |
225 | } | |
1da177e4 LT |
226 | |
227 | /* | |
228 | * The reset command takes a long time to execute. | |
229 | */ | |
230 | timeout = msecs_to_jiffies(command == PS2_CMD_RESET_BAT ? 4000 : 500); | |
231 | ||
232 | timeout = wait_event_timeout(ps2dev->wait, | |
233 | !(ps2dev->flags & PS2_FLAG_CMD1), timeout); | |
234 | ||
a3ce6ea4 | 235 | if (ps2dev->cmdcnt && !(ps2dev->flags & PS2_FLAG_CMD1)) { |
1da177e4 | 236 | |
905ab9d1 | 237 | timeout = ps2_adjust_timeout(ps2dev, command, timeout); |
1da177e4 LT |
238 | wait_event_timeout(ps2dev->wait, |
239 | !(ps2dev->flags & PS2_FLAG_CMD), timeout); | |
240 | } | |
241 | ||
218c1f76 DV |
242 | serio_pause_rx(ps2dev->serio); |
243 | ||
1da177e4 LT |
244 | if (param) |
245 | for (i = 0; i < receive; i++) | |
246 | param[i] = ps2dev->cmdbuf[(receive - 1) - i]; | |
247 | ||
248 | if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) | |
218c1f76 | 249 | goto out_reset_flags; |
1da177e4 LT |
250 | |
251 | rc = 0; | |
252 | ||
218c1f76 | 253 | out_reset_flags: |
1da177e4 LT |
254 | ps2dev->flags = 0; |
255 | serio_continue_rx(ps2dev->serio); | |
256 | ||
fc69f4a6 TL |
257 | return rc; |
258 | } | |
259 | EXPORT_SYMBOL(__ps2_command); | |
260 | ||
261 | int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) | |
262 | { | |
263 | int rc; | |
264 | ||
181d683d | 265 | ps2_begin_command(ps2dev); |
fc69f4a6 | 266 | rc = __ps2_command(ps2dev, param, command); |
181d683d | 267 | ps2_end_command(ps2dev); |
fc69f4a6 | 268 | |
1da177e4 LT |
269 | return rc; |
270 | } | |
5206c0d5 | 271 | EXPORT_SYMBOL(ps2_command); |
1da177e4 | 272 | |
1da177e4 LT |
273 | /* |
274 | * ps2_init() initializes ps2dev structure | |
275 | */ | |
276 | ||
277 | void ps2_init(struct ps2dev *ps2dev, struct serio *serio) | |
278 | { | |
c4e32e9f | 279 | mutex_init(&ps2dev->cmd_mutex); |
88aa0103 | 280 | lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth); |
1da177e4 LT |
281 | init_waitqueue_head(&ps2dev->wait); |
282 | ps2dev->serio = serio; | |
283 | } | |
5206c0d5 | 284 | EXPORT_SYMBOL(ps2_init); |
1da177e4 LT |
285 | |
286 | /* | |
287 | * ps2_handle_ack() is supposed to be used in interrupt handler | |
288 | * to properly process ACK/NAK of a command from a PS/2 device. | |
289 | */ | |
290 | ||
291 | int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data) | |
292 | { | |
293 | switch (data) { | |
294 | case PS2_RET_ACK: | |
295 | ps2dev->nak = 0; | |
296 | break; | |
297 | ||
298 | case PS2_RET_NAK: | |
a2d781fc DT |
299 | ps2dev->flags |= PS2_FLAG_NAK; |
300 | ps2dev->nak = PS2_RET_NAK; | |
1da177e4 LT |
301 | break; |
302 | ||
a2d781fc DT |
303 | case PS2_RET_ERR: |
304 | if (ps2dev->flags & PS2_FLAG_NAK) { | |
305 | ps2dev->flags &= ~PS2_FLAG_NAK; | |
306 | ps2dev->nak = PS2_RET_ERR; | |
307 | break; | |
308 | } | |
309 | ||
1da177e4 LT |
310 | /* |
311 | * Workaround for mice which don't ACK the Get ID command. | |
312 | * These are valid mouse IDs that we recognize. | |
313 | */ | |
314 | case 0x00: | |
315 | case 0x03: | |
316 | case 0x04: | |
317 | if (ps2dev->flags & PS2_FLAG_WAITID) { | |
318 | ps2dev->nak = 0; | |
319 | break; | |
320 | } | |
321 | /* Fall through */ | |
322 | default: | |
323 | return 0; | |
324 | } | |
325 | ||
326 | ||
a2d781fc DT |
327 | if (!ps2dev->nak) { |
328 | ps2dev->flags &= ~PS2_FLAG_NAK; | |
329 | if (ps2dev->cmdcnt) | |
330 | ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; | |
331 | } | |
1da177e4 LT |
332 | |
333 | ps2dev->flags &= ~PS2_FLAG_ACK; | |
334 | wake_up(&ps2dev->wait); | |
335 | ||
336 | if (data != PS2_RET_ACK) | |
337 | ps2_handle_response(ps2dev, data); | |
338 | ||
339 | return 1; | |
340 | } | |
5206c0d5 | 341 | EXPORT_SYMBOL(ps2_handle_ack); |
1da177e4 LT |
342 | |
343 | /* | |
344 | * ps2_handle_response() is supposed to be used in interrupt handler | |
345 | * to properly store device's response to a command and notify process | |
346 | * waiting for completion of the command. | |
347 | */ | |
348 | ||
349 | int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data) | |
350 | { | |
351 | if (ps2dev->cmdcnt) | |
352 | ps2dev->cmdbuf[--ps2dev->cmdcnt] = data; | |
353 | ||
354 | if (ps2dev->flags & PS2_FLAG_CMD1) { | |
355 | ps2dev->flags &= ~PS2_FLAG_CMD1; | |
356 | if (ps2dev->cmdcnt) | |
357 | wake_up(&ps2dev->wait); | |
358 | } | |
359 | ||
360 | if (!ps2dev->cmdcnt) { | |
361 | ps2dev->flags &= ~PS2_FLAG_CMD; | |
362 | wake_up(&ps2dev->wait); | |
363 | } | |
364 | ||
365 | return 1; | |
366 | } | |
5206c0d5 | 367 | EXPORT_SYMBOL(ps2_handle_response); |
1da177e4 LT |
368 | |
369 | void ps2_cmd_aborted(struct ps2dev *ps2dev) | |
370 | { | |
371 | if (ps2dev->flags & PS2_FLAG_ACK) | |
372 | ps2dev->nak = 1; | |
373 | ||
374 | if (ps2dev->flags & (PS2_FLAG_ACK | PS2_FLAG_CMD)) | |
375 | wake_up(&ps2dev->wait); | |
376 | ||
a2d781fc DT |
377 | /* reset all flags except last nack */ |
378 | ps2dev->flags &= PS2_FLAG_NAK; | |
1da177e4 | 379 | } |
5206c0d5 | 380 | EXPORT_SYMBOL(ps2_cmd_aborted); |