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> | |
16 | #include <linux/moduleparam.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/interrupt.h> | |
19 | #include <linux/input.h> | |
20 | #include <linux/serio.h> | |
21 | #include <linux/init.h> | |
22 | #include <linux/libps2.h> | |
23 | ||
24 | #define DRIVER_DESC "PS/2 driver library" | |
25 | ||
26 | MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>"); | |
27 | MODULE_DESCRIPTION("PS/2 driver library"); | |
28 | MODULE_LICENSE("GPL"); | |
29 | ||
1da177e4 LT |
30 | /* Work structure to schedule execution of a command */ |
31 | struct ps2work { | |
32 | struct work_struct work; | |
33 | struct ps2dev *ps2dev; | |
34 | int command; | |
35 | unsigned char param[0]; | |
36 | }; | |
37 | ||
38 | ||
39 | /* | |
c611763d DT |
40 | * ps2_sendbyte() sends a byte to the device and waits for acknowledge. |
41 | * It doesn't handle retransmission, though it could - because if there | |
42 | * is a need for retransmissions device has to be replaced anyway. | |
1da177e4 | 43 | * |
c611763d | 44 | * ps2_sendbyte() can only be called from a process context. |
1da177e4 LT |
45 | */ |
46 | ||
47 | int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout) | |
48 | { | |
49 | serio_pause_rx(ps2dev->serio); | |
50 | ps2dev->nak = 1; | |
51 | ps2dev->flags |= PS2_FLAG_ACK; | |
52 | serio_continue_rx(ps2dev->serio); | |
53 | ||
54 | if (serio_write(ps2dev->serio, byte) == 0) | |
55 | wait_event_timeout(ps2dev->wait, | |
56 | !(ps2dev->flags & PS2_FLAG_ACK), | |
57 | msecs_to_jiffies(timeout)); | |
58 | ||
59 | serio_pause_rx(ps2dev->serio); | |
60 | ps2dev->flags &= ~PS2_FLAG_ACK; | |
61 | serio_continue_rx(ps2dev->serio); | |
62 | ||
63 | return -ps2dev->nak; | |
64 | } | |
5206c0d5 | 65 | EXPORT_SYMBOL(ps2_sendbyte); |
1da177e4 | 66 | |
c611763d DT |
67 | /* |
68 | * ps2_drain() waits for device to transmit requested number of bytes | |
69 | * and discards them. | |
70 | */ | |
71 | ||
72 | void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout) | |
73 | { | |
74 | if (maxbytes > sizeof(ps2dev->cmdbuf)) { | |
75 | WARN_ON(1); | |
76 | maxbytes = sizeof(ps2dev->cmdbuf); | |
77 | } | |
78 | ||
c4e32e9f | 79 | mutex_lock(&ps2dev->cmd_mutex); |
c611763d DT |
80 | |
81 | serio_pause_rx(ps2dev->serio); | |
82 | ps2dev->flags = PS2_FLAG_CMD; | |
83 | ps2dev->cmdcnt = maxbytes; | |
84 | serio_continue_rx(ps2dev->serio); | |
85 | ||
86 | wait_event_timeout(ps2dev->wait, | |
87 | !(ps2dev->flags & PS2_FLAG_CMD), | |
88 | msecs_to_jiffies(timeout)); | |
c4e32e9f | 89 | mutex_unlock(&ps2dev->cmd_mutex); |
c611763d | 90 | } |
5206c0d5 | 91 | EXPORT_SYMBOL(ps2_drain); |
c611763d | 92 | |
905ab9d1 DT |
93 | /* |
94 | * ps2_is_keyboard_id() checks received ID byte against the list of | |
95 | * known keyboard IDs. | |
96 | */ | |
97 | ||
9807879b | 98 | int ps2_is_keyboard_id(char id_byte) |
905ab9d1 | 99 | { |
9807879b | 100 | const static char keyboard_ids[] = { |
905ab9d1 DT |
101 | 0xab, /* Regular keyboards */ |
102 | 0xac, /* NCD Sun keyboard */ | |
103 | 0x2b, /* Trust keyboard, translated */ | |
104 | 0x5d, /* Trust keyboard */ | |
105 | 0x60, /* NMB SGI keyboard, translated */ | |
106 | 0x47, /* NMB SGI keyboard */ | |
107 | }; | |
108 | ||
109 | return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL; | |
110 | } | |
5206c0d5 | 111 | EXPORT_SYMBOL(ps2_is_keyboard_id); |
905ab9d1 DT |
112 | |
113 | /* | |
114 | * ps2_adjust_timeout() is called after receiving 1st byte of command | |
115 | * response and tries to reduce remaining timeout to speed up command | |
116 | * completion. | |
117 | */ | |
118 | ||
119 | static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout) | |
120 | { | |
121 | switch (command) { | |
122 | case PS2_CMD_RESET_BAT: | |
123 | /* | |
124 | * Device has sent the first response byte after | |
125 | * reset command, reset is thus done, so we can | |
126 | * shorten the timeout. | |
127 | * The next byte will come soon (keyboard) or not | |
128 | * at all (mouse). | |
129 | */ | |
130 | if (timeout > msecs_to_jiffies(100)) | |
131 | timeout = msecs_to_jiffies(100); | |
132 | break; | |
133 | ||
134 | case PS2_CMD_GETID: | |
9807879b DT |
135 | /* |
136 | * Microsoft Natural Elite keyboard responds to | |
137 | * the GET ID command as it were a mouse, with | |
138 | * a single byte. Fail the command so atkbd will | |
139 | * use alternative probe to detect it. | |
140 | */ | |
141 | if (ps2dev->cmdbuf[1] == 0xaa) { | |
142 | serio_pause_rx(ps2dev->serio); | |
143 | ps2dev->flags = 0; | |
144 | serio_continue_rx(ps2dev->serio); | |
145 | timeout = 0; | |
146 | } | |
147 | ||
905ab9d1 DT |
148 | /* |
149 | * If device behind the port is not a keyboard there | |
150 | * won't be 2nd byte of ID response. | |
151 | */ | |
152 | if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) { | |
153 | serio_pause_rx(ps2dev->serio); | |
154 | ps2dev->flags = ps2dev->cmdcnt = 0; | |
155 | serio_continue_rx(ps2dev->serio); | |
156 | timeout = 0; | |
157 | } | |
158 | break; | |
159 | ||
160 | default: | |
161 | break; | |
162 | } | |
163 | ||
164 | return timeout; | |
165 | } | |
166 | ||
1da177e4 LT |
167 | /* |
168 | * ps2_command() sends a command and its parameters to the mouse, | |
169 | * then waits for the response and puts it in the param array. | |
170 | * | |
171 | * ps2_command() can only be called from a process context | |
172 | */ | |
173 | ||
174 | int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command) | |
175 | { | |
176 | int timeout; | |
177 | int send = (command >> 12) & 0xf; | |
178 | int receive = (command >> 8) & 0xf; | |
179 | int rc = -1; | |
180 | int i; | |
181 | ||
c611763d DT |
182 | if (receive > sizeof(ps2dev->cmdbuf)) { |
183 | WARN_ON(1); | |
184 | return -1; | |
185 | } | |
186 | ||
95349fe8 DT |
187 | if (send && !param) { |
188 | WARN_ON(1); | |
189 | return -1; | |
190 | } | |
191 | ||
88aa0103 | 192 | mutex_lock(&ps2dev->cmd_mutex); |
1da177e4 LT |
193 | |
194 | serio_pause_rx(ps2dev->serio); | |
195 | ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; | |
196 | ps2dev->cmdcnt = receive; | |
197 | if (receive && param) | |
198 | for (i = 0; i < receive; i++) | |
199 | ps2dev->cmdbuf[(receive - 1) - i] = param[i]; | |
200 | serio_continue_rx(ps2dev->serio); | |
201 | ||
202 | /* | |
203 | * Some devices (Synaptics) peform the reset before | |
204 | * ACKing the reset command, and so it can take a long | |
205 | * time before the ACK arrrives. | |
206 | */ | |
c611763d DT |
207 | if (ps2_sendbyte(ps2dev, command & 0xff, |
208 | command == PS2_CMD_RESET_BAT ? 1000 : 200)) | |
209 | goto out; | |
1da177e4 LT |
210 | |
211 | for (i = 0; i < send; i++) | |
212 | if (ps2_sendbyte(ps2dev, param[i], 200)) | |
213 | goto out; | |
214 | ||
215 | /* | |
216 | * The reset command takes a long time to execute. | |
217 | */ | |
218 | timeout = msecs_to_jiffies(command == PS2_CMD_RESET_BAT ? 4000 : 500); | |
219 | ||
220 | timeout = wait_event_timeout(ps2dev->wait, | |
221 | !(ps2dev->flags & PS2_FLAG_CMD1), timeout); | |
222 | ||
223 | if (ps2dev->cmdcnt && timeout > 0) { | |
224 | ||
905ab9d1 | 225 | timeout = ps2_adjust_timeout(ps2dev, command, timeout); |
1da177e4 LT |
226 | wait_event_timeout(ps2dev->wait, |
227 | !(ps2dev->flags & PS2_FLAG_CMD), timeout); | |
228 | } | |
229 | ||
230 | if (param) | |
231 | for (i = 0; i < receive; i++) | |
232 | param[i] = ps2dev->cmdbuf[(receive - 1) - i]; | |
233 | ||
234 | if (ps2dev->cmdcnt && (command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) | |
235 | goto out; | |
236 | ||
237 | rc = 0; | |
238 | ||
905ab9d1 | 239 | out: |
1da177e4 LT |
240 | serio_pause_rx(ps2dev->serio); |
241 | ps2dev->flags = 0; | |
242 | serio_continue_rx(ps2dev->serio); | |
243 | ||
c4e32e9f | 244 | mutex_unlock(&ps2dev->cmd_mutex); |
1da177e4 LT |
245 | return rc; |
246 | } | |
5206c0d5 | 247 | EXPORT_SYMBOL(ps2_command); |
1da177e4 LT |
248 | |
249 | /* | |
250 | * ps2_execute_scheduled_command() sends a command, previously scheduled by | |
251 | * ps2_schedule_command(), to a PS/2 device (keyboard, mouse, etc.) | |
252 | */ | |
253 | ||
254 | static void ps2_execute_scheduled_command(void *data) | |
255 | { | |
256 | struct ps2work *ps2work = data; | |
257 | ||
258 | ps2_command(ps2work->ps2dev, ps2work->param, ps2work->command); | |
259 | kfree(ps2work); | |
260 | } | |
261 | ||
262 | /* | |
263 | * ps2_schedule_command() allows to schedule delayed execution of a PS/2 | |
264 | * command and can be used to issue a command from an interrupt or softirq | |
265 | * context. | |
266 | */ | |
267 | ||
268 | int ps2_schedule_command(struct ps2dev *ps2dev, unsigned char *param, int command) | |
269 | { | |
270 | struct ps2work *ps2work; | |
271 | int send = (command >> 12) & 0xf; | |
272 | int receive = (command >> 8) & 0xf; | |
273 | ||
274 | if (!(ps2work = kmalloc(sizeof(struct ps2work) + max(send, receive), GFP_ATOMIC))) | |
275 | return -1; | |
276 | ||
277 | memset(ps2work, 0, sizeof(struct ps2work)); | |
278 | ps2work->ps2dev = ps2dev; | |
279 | ps2work->command = command; | |
280 | memcpy(ps2work->param, param, send); | |
281 | INIT_WORK(&ps2work->work, ps2_execute_scheduled_command, ps2work); | |
282 | ||
283 | if (!schedule_work(&ps2work->work)) { | |
284 | kfree(ps2work); | |
285 | return -1; | |
286 | } | |
287 | ||
288 | return 0; | |
289 | } | |
5206c0d5 | 290 | EXPORT_SYMBOL(ps2_schedule_command); |
1da177e4 LT |
291 | |
292 | /* | |
293 | * ps2_init() initializes ps2dev structure | |
294 | */ | |
295 | ||
296 | void ps2_init(struct ps2dev *ps2dev, struct serio *serio) | |
297 | { | |
c4e32e9f | 298 | mutex_init(&ps2dev->cmd_mutex); |
88aa0103 | 299 | lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth); |
1da177e4 LT |
300 | init_waitqueue_head(&ps2dev->wait); |
301 | ps2dev->serio = serio; | |
302 | } | |
5206c0d5 | 303 | EXPORT_SYMBOL(ps2_init); |
1da177e4 LT |
304 | |
305 | /* | |
306 | * ps2_handle_ack() is supposed to be used in interrupt handler | |
307 | * to properly process ACK/NAK of a command from a PS/2 device. | |
308 | */ | |
309 | ||
310 | int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data) | |
311 | { | |
312 | switch (data) { | |
313 | case PS2_RET_ACK: | |
314 | ps2dev->nak = 0; | |
315 | break; | |
316 | ||
317 | case PS2_RET_NAK: | |
318 | ps2dev->nak = 1; | |
319 | break; | |
320 | ||
321 | /* | |
322 | * Workaround for mice which don't ACK the Get ID command. | |
323 | * These are valid mouse IDs that we recognize. | |
324 | */ | |
325 | case 0x00: | |
326 | case 0x03: | |
327 | case 0x04: | |
328 | if (ps2dev->flags & PS2_FLAG_WAITID) { | |
329 | ps2dev->nak = 0; | |
330 | break; | |
331 | } | |
332 | /* Fall through */ | |
333 | default: | |
334 | return 0; | |
335 | } | |
336 | ||
337 | ||
338 | if (!ps2dev->nak && ps2dev->cmdcnt) | |
339 | ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; | |
340 | ||
341 | ps2dev->flags &= ~PS2_FLAG_ACK; | |
342 | wake_up(&ps2dev->wait); | |
343 | ||
344 | if (data != PS2_RET_ACK) | |
345 | ps2_handle_response(ps2dev, data); | |
346 | ||
347 | return 1; | |
348 | } | |
5206c0d5 | 349 | EXPORT_SYMBOL(ps2_handle_ack); |
1da177e4 LT |
350 | |
351 | /* | |
352 | * ps2_handle_response() is supposed to be used in interrupt handler | |
353 | * to properly store device's response to a command and notify process | |
354 | * waiting for completion of the command. | |
355 | */ | |
356 | ||
357 | int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data) | |
358 | { | |
359 | if (ps2dev->cmdcnt) | |
360 | ps2dev->cmdbuf[--ps2dev->cmdcnt] = data; | |
361 | ||
362 | if (ps2dev->flags & PS2_FLAG_CMD1) { | |
363 | ps2dev->flags &= ~PS2_FLAG_CMD1; | |
364 | if (ps2dev->cmdcnt) | |
365 | wake_up(&ps2dev->wait); | |
366 | } | |
367 | ||
368 | if (!ps2dev->cmdcnt) { | |
369 | ps2dev->flags &= ~PS2_FLAG_CMD; | |
370 | wake_up(&ps2dev->wait); | |
371 | } | |
372 | ||
373 | return 1; | |
374 | } | |
5206c0d5 | 375 | EXPORT_SYMBOL(ps2_handle_response); |
1da177e4 LT |
376 | |
377 | void ps2_cmd_aborted(struct ps2dev *ps2dev) | |
378 | { | |
379 | if (ps2dev->flags & PS2_FLAG_ACK) | |
380 | ps2dev->nak = 1; | |
381 | ||
382 | if (ps2dev->flags & (PS2_FLAG_ACK | PS2_FLAG_CMD)) | |
383 | wake_up(&ps2dev->wait); | |
384 | ||
385 | ps2dev->flags = 0; | |
386 | } | |
5206c0d5 | 387 | EXPORT_SYMBOL(ps2_cmd_aborted); |