1 /* APM emulation layer for PowerMac 2 * 3 * Copyright 2001 Benjamin Herrenschmidt (benh@kernel.crashing.org) 4 * 5 * Lots of code inherited from apm.c, see appropriate notice in 6 * arch/i386/kernel/apm.c 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2, or (at your option) any 11 * later version. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 24 #include <linux/poll.h> 25 #include <linux/types.h> 26 #include <linux/stddef.h> 27 #include <linux/timer.h> 28 #include <linux/fcntl.h> 29 #include <linux/slab.h> 30 #include <linux/stat.h> 31 #include <linux/proc_fs.h> 32 #include <linux/miscdevice.h> 33 #include <linux/apm_bios.h> 34 #include <linux/init.h> 35 #include <linux/sched.h> 36 #include <linux/pm.h> 37 #include <linux/kernel.h> 38 #include <linux/smp_lock.h> 39 40 #include <linux/adb.h> 41 #include <linux/pmu.h> 42 43 #include <asm/system.h> 44 #include <asm/uaccess.h> 45 #include <asm/machdep.h> 46 47 #undef DEBUG 48 49 #ifdef DEBUG 50 #define DBG(args...) printk(KERN_DEBUG args) 51 //#define DBG(args...) xmon_printf(args) 52 #else 53 #define DBG(args...) do { } while (0) 54 #endif 55 56 /* 57 * The apm_bios device is one of the misc char devices. 58 * This is its minor number. 59 */ 60 #define APM_MINOR_DEV 134 61 62 /* 63 * Maximum number of events stored 64 */ 65 #define APM_MAX_EVENTS 20 66 67 #define FAKE_APM_BIOS_VERSION 0x0101 68 69 #define APM_USER_NOTIFY_TIMEOUT (5*HZ) 70 71 /* 72 * The per-file APM data 73 */ 74 struct apm_user { 75 int magic; 76 struct apm_user * next; 77 int suser: 1; 78 int suspend_waiting: 1; 79 int suspends_pending; 80 int suspends_read; 81 int event_head; 82 int event_tail; 83 apm_event_t events[APM_MAX_EVENTS]; 84 }; 85 86 /* 87 * The magic number in apm_user 88 */ 89 #define APM_BIOS_MAGIC 0x4101 90 91 /* 92 * Local variables 93 */ 94 static int suspends_pending; 95 96 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue); 97 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue); 98 static struct apm_user * user_list; 99 100 static int apm_notify_sleep(struct pmu_sleep_notifier *self, int when); 101 static struct pmu_sleep_notifier apm_sleep_notifier = { 102 apm_notify_sleep, 103 SLEEP_LEVEL_USERLAND, 104 }; 105 106 static char driver_version[] = "0.5"; /* no spaces */ 107 108 #ifdef DEBUG 109 static char * apm_event_name[] = { 110 "system standby", 111 "system suspend", 112 "normal resume", 113 "critical resume", 114 "low battery", 115 "power status change", 116 "update time", 117 "critical suspend", 118 "user standby", 119 "user suspend", 120 "system standby resume", 121 "capabilities change" 122 }; 123 #define NR_APM_EVENT_NAME \ 124 (sizeof(apm_event_name) / sizeof(apm_event_name[0])) 125 126 #endif 127 128 static int queue_empty(struct apm_user *as) 129 { 130 return as->event_head == as->event_tail; 131 } 132 133 static apm_event_t get_queued_event(struct apm_user *as) 134 { 135 as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS; 136 return as->events[as->event_tail]; 137 } 138 139 static void queue_event(apm_event_t event, struct apm_user *sender) 140 { 141 struct apm_user * as; 142 143 DBG("apm_emu: queue_event(%s)\n", apm_event_name[event-1]); 144 if (user_list == NULL) 145 return; 146 for (as = user_list; as != NULL; as = as->next) { 147 if (as == sender) 148 continue; 149 as->event_head = (as->event_head + 1) % APM_MAX_EVENTS; 150 if (as->event_head == as->event_tail) { 151 static int notified; 152 153 if (notified++ == 0) 154 printk(KERN_ERR "apm_emu: an event queue overflowed\n"); 155 as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS; 156 } 157 as->events[as->event_head] = event; 158 if (!as->suser) 159 continue; 160 switch (event) { 161 case APM_SYS_SUSPEND: 162 case APM_USER_SUSPEND: 163 as->suspends_pending++; 164 suspends_pending++; 165 break; 166 case APM_NORMAL_RESUME: 167 as->suspend_waiting = 0; 168 break; 169 } 170 } 171 wake_up_interruptible(&apm_waitqueue); 172 } 173 174 static int check_apm_user(struct apm_user *as, const char *func) 175 { 176 if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) { 177 printk(KERN_ERR "apm_emu: %s passed bad filp\n", func); 178 return 1; 179 } 180 return 0; 181 } 182 183 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos) 184 { 185 struct apm_user * as; 186 size_t i; 187 apm_event_t event; 188 DECLARE_WAITQUEUE(wait, current); 189 190 as = fp->private_data; 191 if (check_apm_user(as, "read")) 192 return -EIO; 193 if (count < sizeof(apm_event_t)) 194 return -EINVAL; 195 if (queue_empty(as)) { 196 if (fp->f_flags & O_NONBLOCK) 197 return -EAGAIN; 198 add_wait_queue(&apm_waitqueue, &wait); 199 repeat: 200 set_current_state(TASK_INTERRUPTIBLE); 201 if (queue_empty(as) && !signal_pending(current)) { 202 schedule(); 203 goto repeat; 204 } 205 set_current_state(TASK_RUNNING); 206 remove_wait_queue(&apm_waitqueue, &wait); 207 } 208 i = count; 209 while ((i >= sizeof(event)) && !queue_empty(as)) { 210 event = get_queued_event(as); 211 DBG("apm_emu: do_read, returning: %s\n", apm_event_name[event-1]); 212 if (copy_to_user(buf, &event, sizeof(event))) { 213 if (i < count) 214 break; 215 return -EFAULT; 216 } 217 switch (event) { 218 case APM_SYS_SUSPEND: 219 case APM_USER_SUSPEND: 220 as->suspends_read++; 221 break; 222 } 223 buf += sizeof(event); 224 i -= sizeof(event); 225 } 226 if (i < count) 227 return count - i; 228 if (signal_pending(current)) 229 return -ERESTARTSYS; 230 return 0; 231 } 232 233 static unsigned int do_poll(struct file *fp, poll_table * wait) 234 { 235 struct apm_user * as; 236 237 as = fp->private_data; 238 if (check_apm_user(as, "poll")) 239 return 0; 240 poll_wait(fp, &apm_waitqueue, wait); 241 if (!queue_empty(as)) 242 return POLLIN | POLLRDNORM; 243 return 0; 244 } 245 246 static int do_ioctl(struct inode * inode, struct file *filp, 247 u_int cmd, u_long arg) 248 { 249 struct apm_user * as; 250 DECLARE_WAITQUEUE(wait, current); 251 252 as = filp->private_data; 253 if (check_apm_user(as, "ioctl")) 254 return -EIO; 255 if (!as->suser) 256 return -EPERM; 257 switch (cmd) { 258 case APM_IOC_SUSPEND: 259 /* If a suspend message was sent to userland, we 260 * consider this as a confirmation message 261 */ 262 if (as->suspends_read > 0) { 263 as->suspends_read--; 264 as->suspends_pending--; 265 suspends_pending--; 266 } else { 267 // Route to PMU suspend ? 268 break; 269 } 270 as->suspend_waiting = 1; 271 add_wait_queue(&apm_waitqueue, &wait); 272 DBG("apm_emu: ioctl waking up sleep waiter !\n"); 273 wake_up(&apm_suspend_waitqueue); 274 mb(); 275 while(as->suspend_waiting && !signal_pending(current)) { 276 set_current_state(TASK_INTERRUPTIBLE); 277 schedule(); 278 } 279 set_current_state(TASK_RUNNING); 280 remove_wait_queue(&apm_waitqueue, &wait); 281 break; 282 default: 283 return -EINVAL; 284 } 285 return 0; 286 } 287 288 static int do_release(struct inode * inode, struct file * filp) 289 { 290 struct apm_user * as; 291 292 as = filp->private_data; 293 if (check_apm_user(as, "release")) 294 return 0; 295 filp->private_data = NULL; 296 lock_kernel(); 297 if (as->suspends_pending > 0) { 298 suspends_pending -= as->suspends_pending; 299 if (suspends_pending <= 0) 300 wake_up(&apm_suspend_waitqueue); 301 } 302 if (user_list == as) 303 user_list = as->next; 304 else { 305 struct apm_user * as1; 306 307 for (as1 = user_list; 308 (as1 != NULL) && (as1->next != as); 309 as1 = as1->next) 310 ; 311 if (as1 == NULL) 312 printk(KERN_ERR "apm: filp not in user list\n"); 313 else 314 as1->next = as->next; 315 } 316 unlock_kernel(); 317 kfree(as); 318 return 0; 319 } 320 321 static int do_open(struct inode * inode, struct file * filp) 322 { 323 struct apm_user * as; 324 325 as = (struct apm_user *)kmalloc(sizeof(*as), GFP_KERNEL); 326 if (as == NULL) { 327 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n", 328 sizeof(*as)); 329 return -ENOMEM; 330 } 331 as->magic = APM_BIOS_MAGIC; 332 as->event_tail = as->event_head = 0; 333 as->suspends_pending = 0; 334 as->suspends_read = 0; 335 /* 336 * XXX - this is a tiny bit broken, when we consider BSD 337 * process accounting. If the device is opened by root, we 338 * instantly flag that we used superuser privs. Who knows, 339 * we might close the device immediately without doing a 340 * privileged operation -- cevans 341 */ 342 as->suser = capable(CAP_SYS_ADMIN); 343 as->next = user_list; 344 user_list = as; 345 filp->private_data = as; 346 347 DBG("apm_emu: opened by %s, suser: %d\n", current->comm, (int)as->suser); 348 349 return 0; 350 } 351 352 /* Wait for all clients to ack the suspend request. APM API 353 * doesn't provide a way to NAK, but this could be added 354 * here. 355 */ 356 static int wait_all_suspend(void) 357 { 358 DECLARE_WAITQUEUE(wait, current); 359 360 add_wait_queue(&apm_suspend_waitqueue, &wait); 361 DBG("apm_emu: wait_all_suspend(), suspends_pending: %d\n", suspends_pending); 362 while(suspends_pending > 0) { 363 set_current_state(TASK_UNINTERRUPTIBLE); 364 schedule(); 365 } 366 set_current_state(TASK_RUNNING); 367 remove_wait_queue(&apm_suspend_waitqueue, &wait); 368 369 DBG("apm_emu: wait_all_suspend() - complete !\n"); 370 371 return 1; 372 } 373 374 static int apm_notify_sleep(struct pmu_sleep_notifier *self, int when) 375 { 376 switch(when) { 377 case PBOOK_SLEEP_REQUEST: 378 queue_event(APM_SYS_SUSPEND, NULL); 379 if (!wait_all_suspend()) 380 return PBOOK_SLEEP_REFUSE; 381 break; 382 case PBOOK_SLEEP_REJECT: 383 case PBOOK_WAKE: 384 queue_event(APM_NORMAL_RESUME, NULL); 385 break; 386 } 387 return PBOOK_SLEEP_OK; 388 } 389 390 #define APM_CRITICAL 10 391 #define APM_LOW 30 392 393 static int apm_emu_get_info(char *buf, char **start, off_t fpos, int length) 394 { 395 /* Arguments, with symbols from linux/apm_bios.h. Information is 396 from the Get Power Status (0x0a) call unless otherwise noted. 397 398 0) Linux driver version (this will change if format changes) 399 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2. 400 2) APM flags from APM Installation Check (0x00): 401 bit 0: APM_16_BIT_SUPPORT 402 bit 1: APM_32_BIT_SUPPORT 403 bit 2: APM_IDLE_SLOWS_CLOCK 404 bit 3: APM_BIOS_DISABLED 405 bit 4: APM_BIOS_DISENGAGED 406 3) AC line status 407 0x00: Off-line 408 0x01: On-line 409 0x02: On backup power (BIOS >= 1.1 only) 410 0xff: Unknown 411 4) Battery status 412 0x00: High 413 0x01: Low 414 0x02: Critical 415 0x03: Charging 416 0x04: Selected battery not present (BIOS >= 1.2 only) 417 0xff: Unknown 418 5) Battery flag 419 bit 0: High 420 bit 1: Low 421 bit 2: Critical 422 bit 3: Charging 423 bit 7: No system battery 424 0xff: Unknown 425 6) Remaining battery life (percentage of charge): 426 0-100: valid 427 -1: Unknown 428 7) Remaining battery life (time units): 429 Number of remaining minutes or seconds 430 -1: Unknown 431 8) min = minutes; sec = seconds */ 432 433 unsigned short ac_line_status; 434 unsigned short battery_status = 0; 435 unsigned short battery_flag = 0xff; 436 int percentage = -1; 437 int time_units = -1; 438 int real_count = 0; 439 int i; 440 char * p = buf; 441 char charging = 0; 442 long charge = -1; 443 long amperage = 0; 444 unsigned long btype = 0; 445 446 ac_line_status = ((pmu_power_flags & PMU_PWR_AC_PRESENT) != 0); 447 for (i=0; i<pmu_battery_count; i++) { 448 if (pmu_batteries[i].flags & PMU_BATT_PRESENT) { 449 battery_status++; 450 if (percentage < 0) 451 percentage = 0; 452 if (charge < 0) 453 charge = 0; 454 percentage += (pmu_batteries[i].charge * 100) / 455 pmu_batteries[i].max_charge; 456 charge += pmu_batteries[i].charge; 457 amperage += pmu_batteries[i].amperage; 458 if (btype == 0) 459 btype = (pmu_batteries[i].flags & PMU_BATT_TYPE_MASK); 460 real_count++; 461 if ((pmu_batteries[i].flags & PMU_BATT_CHARGING)) 462 charging++; 463 } 464 } 465 if (0 == battery_status) 466 ac_line_status = 1; 467 battery_status = 0xff; 468 if (real_count) { 469 if (amperage < 0) { 470 if (btype == PMU_BATT_TYPE_SMART) 471 time_units = (charge * 59) / (amperage * -1); 472 else 473 time_units = (charge * 16440) / (amperage * -60); 474 } 475 percentage /= real_count; 476 if (charging > 0) { 477 battery_status = 0x03; 478 battery_flag = 0x08; 479 } else if (percentage <= APM_CRITICAL) { 480 battery_status = 0x02; 481 battery_flag = 0x04; 482 } else if (percentage <= APM_LOW) { 483 battery_status = 0x01; 484 battery_flag = 0x02; 485 } else { 486 battery_status = 0x00; 487 battery_flag = 0x01; 488 } 489 } 490 p += sprintf(p, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n", 491 driver_version, 492 (FAKE_APM_BIOS_VERSION >> 8) & 0xff, 493 FAKE_APM_BIOS_VERSION & 0xff, 494 0, 495 ac_line_status, 496 battery_status, 497 battery_flag, 498 percentage, 499 time_units, 500 "min"); 501 502 return p - buf; 503 } 504 505 static struct file_operations apm_bios_fops = { 506 .owner = THIS_MODULE, 507 .read = do_read, 508 .poll = do_poll, 509 .ioctl = do_ioctl, 510 .open = do_open, 511 .release = do_release, 512 }; 513 514 static struct miscdevice apm_device = { 515 APM_MINOR_DEV, 516 "apm_bios", 517 &apm_bios_fops 518 }; 519 520 static int __init apm_emu_init(void) 521 { 522 struct proc_dir_entry *apm_proc; 523 524 if (sys_ctrler != SYS_CTRLER_PMU) { 525 printk(KERN_INFO "apm_emu: Requires a machine with a PMU.\n"); 526 return -ENODEV; 527 } 528 529 apm_proc = create_proc_info_entry("apm", 0, NULL, apm_emu_get_info); 530 if (apm_proc) 531 apm_proc->owner = THIS_MODULE; 532 533 misc_register(&apm_device); 534 535 pmu_register_sleep_notifier(&apm_sleep_notifier); 536 537 printk(KERN_INFO "apm_emu: APM Emulation %s initialized.\n", driver_version); 538 539 return 0; 540 } 541 542 static void __exit apm_emu_exit(void) 543 { 544 pmu_unregister_sleep_notifier(&apm_sleep_notifier); 545 misc_deregister(&apm_device); 546 remove_proc_entry("apm", NULL); 547 548 printk(KERN_INFO "apm_emu: APM Emulation removed.\n"); 549 } 550 551 module_init(apm_emu_init); 552 module_exit(apm_emu_exit); 553 554 MODULE_AUTHOR("Benjamin Herrenschmidt"); 555 MODULE_DESCRIPTION("APM emulation layer for PowerMac"); 556 MODULE_LICENSE("GPL"); 557 558