Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | /* |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 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. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | * |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 44 | * ps2_sendbyte() can only be called from a process context. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 65 | EXPORT_SYMBOL(ps2_sendbyte); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | |
| 67 | /* |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 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 | |
Arjan van de Ven | c4e32e9 | 2006-02-19 00:21:55 -0500 | [diff] [blame] | 79 | mutex_lock(&ps2dev->cmd_mutex); |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 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)); |
Arjan van de Ven | c4e32e9 | 2006-02-19 00:21:55 -0500 | [diff] [blame] | 89 | mutex_unlock(&ps2dev->cmd_mutex); |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 90 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 91 | EXPORT_SYMBOL(ps2_drain); |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 92 | |
| 93 | /* |
Dmitry Torokhov | 905ab9d | 2005-06-01 02:39:53 -0500 | [diff] [blame] | 94 | * ps2_is_keyboard_id() checks received ID byte against the list of |
| 95 | * known keyboard IDs. |
| 96 | */ |
| 97 | |
Dmitry Torokhov | 9807879 | 2006-09-14 01:31:27 -0400 | [diff] [blame] | 98 | int ps2_is_keyboard_id(char id_byte) |
Dmitry Torokhov | 905ab9d | 2005-06-01 02:39:53 -0500 | [diff] [blame] | 99 | { |
Tobias Klauser | c5a69d5 | 2007-02-17 20:11:19 +0100 | [diff] [blame^] | 100 | static const char keyboard_ids[] = { |
Dmitry Torokhov | 905ab9d | 2005-06-01 02:39:53 -0500 | [diff] [blame] | 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 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 111 | EXPORT_SYMBOL(ps2_is_keyboard_id); |
Dmitry Torokhov | 905ab9d | 2005-06-01 02:39:53 -0500 | [diff] [blame] | 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: |
| 135 | /* |
Dmitry Torokhov | 9807879 | 2006-09-14 01:31:27 -0400 | [diff] [blame] | 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 | |
| 148 | /* |
Dmitry Torokhov | 905ab9d | 2005-06-01 02:39:53 -0500 | [diff] [blame] | 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 | |
| 167 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 182 | if (receive > sizeof(ps2dev->cmdbuf)) { |
| 183 | WARN_ON(1); |
| 184 | return -1; |
| 185 | } |
| 186 | |
Dmitry Torokhov | 95349fe | 2006-07-06 23:54:48 -0400 | [diff] [blame] | 187 | if (send && !param) { |
| 188 | WARN_ON(1); |
| 189 | return -1; |
| 190 | } |
| 191 | |
Jiri Kosina | 88aa010 | 2006-10-11 01:45:31 -0400 | [diff] [blame] | 192 | mutex_lock(&ps2dev->cmd_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
Dmitry Torokhov | c611763 | 2005-06-01 02:39:51 -0500 | [diff] [blame] | 207 | if (ps2_sendbyte(ps2dev, command & 0xff, |
| 208 | command == PS2_CMD_RESET_BAT ? 1000 : 200)) |
| 209 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Dmitry Torokhov | 905ab9d | 2005-06-01 02:39:53 -0500 | [diff] [blame] | 225 | timeout = ps2_adjust_timeout(ps2dev, command, timeout); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Dmitry Torokhov | 905ab9d | 2005-06-01 02:39:53 -0500 | [diff] [blame] | 239 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | serio_pause_rx(ps2dev->serio); |
| 241 | ps2dev->flags = 0; |
| 242 | serio_continue_rx(ps2dev->serio); |
| 243 | |
Arjan van de Ven | c4e32e9 | 2006-02-19 00:21:55 -0500 | [diff] [blame] | 244 | mutex_unlock(&ps2dev->cmd_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | return rc; |
| 246 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 247 | EXPORT_SYMBOL(ps2_command); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 254 | static void ps2_execute_scheduled_command(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | { |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 256 | struct ps2work *ps2work = container_of(work, struct ps2work, work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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); |
David Howells | 65f27f3 | 2006-11-22 14:55:48 +0000 | [diff] [blame] | 281 | INIT_WORK(&ps2work->work, ps2_execute_scheduled_command); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | |
| 283 | if (!schedule_work(&ps2work->work)) { |
| 284 | kfree(ps2work); |
| 285 | return -1; |
| 286 | } |
| 287 | |
| 288 | return 0; |
| 289 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 290 | EXPORT_SYMBOL(ps2_schedule_command); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | |
| 292 | /* |
| 293 | * ps2_init() initializes ps2dev structure |
| 294 | */ |
| 295 | |
| 296 | void ps2_init(struct ps2dev *ps2dev, struct serio *serio) |
| 297 | { |
Arjan van de Ven | c4e32e9 | 2006-02-19 00:21:55 -0500 | [diff] [blame] | 298 | mutex_init(&ps2dev->cmd_mutex); |
Jiri Kosina | 88aa010 | 2006-10-11 01:45:31 -0400 | [diff] [blame] | 299 | lockdep_set_subclass(&ps2dev->cmd_mutex, serio->depth); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | init_waitqueue_head(&ps2dev->wait); |
| 301 | ps2dev->serio = serio; |
| 302 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 303 | EXPORT_SYMBOL(ps2_init); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 349 | EXPORT_SYMBOL(ps2_handle_ack); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 375 | EXPORT_SYMBOL(ps2_handle_response); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | } |
Dmitry Torokhov | 5206c0d | 2006-09-14 01:31:40 -0400 | [diff] [blame] | 387 | EXPORT_SYMBOL(ps2_cmd_aborted); |