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14#include <linux/delay.h>
15#include <linux/module.h>
16#include <linux/sched.h>
17#include <linux/interrupt.h>
18#include <linux/input.h>
19#include <linux/serio.h>
20#include <linux/i8042.h>
21#include <linux/libps2.h>
22
23#define DRIVER_DESC "PS/2 driver library"
24
25MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
26MODULE_DESCRIPTION("PS/2 driver library");
27MODULE_LICENSE("GPL");
28
29
30
31
32
33
34
35
36
37int 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}
55EXPORT_SYMBOL(ps2_sendbyte);
56
57void ps2_begin_command(struct ps2dev *ps2dev)
58{
59 struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex;
60
61 mutex_lock(m);
62}
63EXPORT_SYMBOL(ps2_begin_command);
64
65void ps2_end_command(struct ps2dev *ps2dev)
66{
67 struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex;
68
69 mutex_unlock(m);
70}
71EXPORT_SYMBOL(ps2_end_command);
72
73
74
75
76
77
78void 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
85 ps2_begin_command(ps2dev);
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));
95
96 ps2_end_command(ps2dev);
97}
98EXPORT_SYMBOL(ps2_drain);
99
100
101
102
103
104
105int ps2_is_keyboard_id(char id_byte)
106{
107 static const char keyboard_ids[] = {
108 0xab,
109 0xac,
110 0x2b,
111 0x5d,
112 0x60,
113 0x47,
114 };
115
116 return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL;
117}
118EXPORT_SYMBOL(ps2_is_keyboard_id);
119
120
121
122
123
124
125
126static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout)
127{
128 switch (command) {
129 case PS2_CMD_RESET_BAT:
130
131
132
133
134
135
136
137 if (timeout > msecs_to_jiffies(100))
138 timeout = msecs_to_jiffies(100);
139 break;
140
141 case PS2_CMD_GETID:
142
143
144
145
146
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
155
156
157
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
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177
178
179
180
181int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command)
182{
183 int timeout;
184 int send = (command >> 12) & 0xf;
185 int receive = (command >> 8) & 0xf;
186 int rc = -1;
187 int i;
188
189 if (receive > sizeof(ps2dev->cmdbuf)) {
190 WARN_ON(1);
191 return -1;
192 }
193
194 if (send && !param) {
195 WARN_ON(1);
196 return -1;
197 }
198
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
209
210
211
212 if (ps2_sendbyte(ps2dev, command & 0xff,
213 command == PS2_CMD_RESET_BAT ? 1000 : 200)) {
214 serio_pause_rx(ps2dev->serio);
215 goto out_reset_flags;
216 }
217
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 }
224
225
226
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
233 if (ps2dev->cmdcnt && !(ps2dev->flags & PS2_FLAG_CMD1)) {
234
235 timeout = ps2_adjust_timeout(ps2dev, command, timeout);
236 wait_event_timeout(ps2dev->wait,
237 !(ps2dev->flags & PS2_FLAG_CMD), timeout);
238 }
239
240 serio_pause_rx(ps2dev->serio);
241
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))
247 goto out_reset_flags;
248
249 rc = 0;
250
251 out_reset_flags:
252 ps2dev->flags = 0;
253 serio_continue_rx(ps2dev->serio);
254
255 return rc;
256}
257EXPORT_SYMBOL(__ps2_command);
258
259int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command)
260{
261 int rc;
262
263 ps2_begin_command(ps2dev);
264 rc = __ps2_command(ps2dev, param, command);
265 ps2_end_command(ps2dev);
266
267 return rc;
268}
269EXPORT_SYMBOL(ps2_command);
270
271
272
273
274
275void ps2_init(struct ps2dev *ps2dev, struct serio *serio)
276{
277 mutex_init(&ps2dev->cmd_mutex);
278 lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth);
279 init_waitqueue_head(&ps2dev->wait);
280 ps2dev->serio = serio;
281}
282EXPORT_SYMBOL(ps2_init);
283
284
285
286
287
288
289int 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:
297 ps2dev->flags |= PS2_FLAG_NAK;
298 ps2dev->nak = PS2_RET_NAK;
299 break;
300
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
308
309
310
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
320 default:
321 return 0;
322 }
323
324
325 if (!ps2dev->nak) {
326 ps2dev->flags &= ~PS2_FLAG_NAK;
327 if (ps2dev->cmdcnt)
328 ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1;
329 }
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}
339EXPORT_SYMBOL(ps2_handle_ack);
340
341
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343
344
345
346
347int 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}
365EXPORT_SYMBOL(ps2_handle_response);
366
367void 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
375
376 ps2dev->flags &= PS2_FLAG_NAK;
377}
378EXPORT_SYMBOL(ps2_cmd_aborted);
379