Pileus Git - ~andy/linux/blob - drivers/staging/android/alarm-dev.c

   1 /* drivers/rtc/alarm-dev.c
   2  *
   3  * Copyright (C) 2007-2009 Google, Inc.
   4  *
   5  * This software is licensed under the terms of the GNU General Public
   6  * License version 2, as published by the Free Software Foundation, and
   7  * may be copied, distributed, and modified under those terms.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  */
  15
  16 #include <linux/time.h>
  17 #include <linux/module.h>
  18 #include <linux/device.h>
  19 #include <linux/miscdevice.h>
  20 #include <linux/fs.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/sched.h>
  23 #include <linux/spinlock.h>
  24 #include <linux/uaccess.h>
  25 #include <linux/alarmtimer.h>
  26 #include "android_alarm.h"
  27
  28 /* XXX - Hack out wakelocks, while they are out of tree */
  29 struct wake_lock {
  30         int i;
  31 };
  32 #define wake_lock(x)
  33 #define wake_lock_timeout(x, y)
  34 #define wake_unlock(x)
  35 #define WAKE_LOCK_SUSPEND 0
  36 #define wake_lock_init(x, y, z) ((x)->i = 1)
  37 #define wake_lock_destroy(x)
  38
  39 #define ANDROID_ALARM_PRINT_INFO (1U << 0)
  40 #define ANDROID_ALARM_PRINT_IO (1U << 1)
  41 #define ANDROID_ALARM_PRINT_INT (1U << 2)
  42
  43
  44 static int debug_mask = ANDROID_ALARM_PRINT_INFO;
  45 module_param_named(debug_mask, debug_mask, int, S_IRUGO | S_IWUSR | S_IWGRP);
  46
  47 #define pr_alarm(debug_level_mask, args...) \
  48         do { \
  49                 if (debug_mask & ANDROID_ALARM_PRINT_##debug_level_mask) { \
  50                         pr_info(args); \
  51                 } \
  52         } while (0)
  53
  54 #define ANDROID_ALARM_WAKEUP_MASK ( \
  55         ANDROID_ALARM_RTC_WAKEUP_MASK | \
  56         ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP_MASK)
  57
  58 /* support old userspace code */
  59 #define ANDROID_ALARM_SET_OLD               _IOW('a', 2, time_t) /* set alarm */
  60 #define ANDROID_ALARM_SET_AND_WAIT_OLD      _IOW('a', 3, time_t)
  61
  62 static int alarm_opened;
  63 static DEFINE_SPINLOCK(alarm_slock);
  64 static struct wake_lock alarm_wake_lock;
  65 static DECLARE_WAIT_QUEUE_HEAD(alarm_wait_queue);
  66 static uint32_t alarm_pending;
  67 static uint32_t alarm_enabled;
  68 static uint32_t wait_pending;
  69
  70 struct devalarm {
  71         union {
  72                 struct hrtimer hrt;
  73                 struct alarm alrm;
  74         } u;
  75         enum android_alarm_type type;
  76 };
  77
  78 static struct devalarm alarms[ANDROID_ALARM_TYPE_COUNT];
  79
  80
  81 static int is_wakeup(enum android_alarm_type type)
  82 {
  83         if (type == ANDROID_ALARM_RTC_WAKEUP ||
  84                         type == ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP)
  85                 return 1;
  86         return 0;
  87 }
  88
  89
  90 static void devalarm_start(struct devalarm *alrm, ktime_t exp)
  91 {
  92         if (is_wakeup(alrm->type))
  93                 alarm_start(&alrm->u.alrm, exp);
  94         else
  95                 hrtimer_start(&alrm->u.hrt, exp, HRTIMER_MODE_ABS);
  96 }
  97
  98
  99 static int devalarm_try_to_cancel(struct devalarm *alrm)
 100 {
 101         int ret;
 102         if (is_wakeup(alrm->type))
 103                 ret = alarm_try_to_cancel(&alrm->u.alrm);
 104         else
 105                 ret = hrtimer_try_to_cancel(&alrm->u.hrt);
 106         return ret;
 107 }
 108
 109 static void devalarm_cancel(struct devalarm *alrm)
 110 {
 111         if (is_wakeup(alrm->type))
 112                 alarm_cancel(&alrm->u.alrm);
 113         else
 114                 hrtimer_cancel(&alrm->u.hrt);
 115 }
 116
 117
 118 static long alarm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 119 {
 120         int rv = 0;
 121         unsigned long flags;
 122         struct timespec new_alarm_time;
 123         struct timespec new_rtc_time;
 124         struct timespec tmp_time;
 125         struct rtc_time new_rtc_tm;
 126         struct rtc_device *rtc_dev;
 127         enum android_alarm_type alarm_type = ANDROID_ALARM_IOCTL_TO_TYPE(cmd);
 128         uint32_t alarm_type_mask = 1U << alarm_type;
 129
 130         if (alarm_type >= ANDROID_ALARM_TYPE_COUNT)
 131                 return -EINVAL;
 132
 133         if (ANDROID_ALARM_BASE_CMD(cmd) != ANDROID_ALARM_GET_TIME(0)) {
 134                 if ((file->f_flags & O_ACCMODE) == O_RDONLY)
 135                         return -EPERM;
 136                 if (file->private_data == NULL &&
 137                     cmd != ANDROID_ALARM_SET_RTC) {
 138                         spin_lock_irqsave(&alarm_slock, flags);
 139                         if (alarm_opened) {
 140                                 spin_unlock_irqrestore(&alarm_slock, flags);
 141                                 return -EBUSY;
 142                         }
 143                         alarm_opened = 1;
 144                         file->private_data = (void *)1;
 145                         spin_unlock_irqrestore(&alarm_slock, flags);
 146                 }
 147         }
 148
 149         switch (ANDROID_ALARM_BASE_CMD(cmd)) {
 150         case ANDROID_ALARM_CLEAR(0):
 151                 spin_lock_irqsave(&alarm_slock, flags);
 152                 pr_alarm(IO, "alarm %d clear\n", alarm_type);
 153                 devalarm_try_to_cancel(&alarms[alarm_type]);
 154                 if (alarm_pending) {
 155                         alarm_pending &= ~alarm_type_mask;
 156                         if (!alarm_pending && !wait_pending)
 157                                 wake_unlock(&alarm_wake_lock);
 158                 }
 159                 alarm_enabled &= ~alarm_type_mask;
 160                 spin_unlock_irqrestore(&alarm_slock, flags);
 161                 break;
 162
 163         case ANDROID_ALARM_SET_OLD:
 164         case ANDROID_ALARM_SET_AND_WAIT_OLD:
 165                 if (get_user(new_alarm_time.tv_sec, (int __user *)arg)) {
 166                         rv = -EFAULT;
 167                         goto err1;
 168                 }
 169                 new_alarm_time.tv_nsec = 0;
 170                 goto from_old_alarm_set;
 171
 172         case ANDROID_ALARM_SET_AND_WAIT(0):
 173         case ANDROID_ALARM_SET(0):
 174                 if (copy_from_user(&new_alarm_time, (void __user *)arg,
 175                     sizeof(new_alarm_time))) {
 176                         rv = -EFAULT;
 177                         goto err1;
 178                 }
 179 from_old_alarm_set:
 180                 spin_lock_irqsave(&alarm_slock, flags);
 181                 pr_alarm(IO, "alarm %d set %ld.%09ld\n", alarm_type,
 182                         new_alarm_time.tv_sec, new_alarm_time.tv_nsec);
 183                 alarm_enabled |= alarm_type_mask;
 184                 devalarm_start(&alarms[alarm_type],
 185                         timespec_to_ktime(new_alarm_time));
 186                 spin_unlock_irqrestore(&alarm_slock, flags);
 187                 if (ANDROID_ALARM_BASE_CMD(cmd) != ANDROID_ALARM_SET_AND_WAIT(0)
 188                     && cmd != ANDROID_ALARM_SET_AND_WAIT_OLD)
 189                         break;
 190                 /* fall though */
 191         case ANDROID_ALARM_WAIT:
 192                 spin_lock_irqsave(&alarm_slock, flags);
 193                 pr_alarm(IO, "alarm wait\n");
 194                 if (!alarm_pending && wait_pending) {
 195                         wake_unlock(&alarm_wake_lock);
 196                         wait_pending = 0;
 197                 }
 198                 spin_unlock_irqrestore(&alarm_slock, flags);
 199                 rv = wait_event_interruptible(alarm_wait_queue, alarm_pending);
 200                 if (rv)
 201                         goto err1;
 202                 spin_lock_irqsave(&alarm_slock, flags);
 203                 rv = alarm_pending;
 204                 wait_pending = 1;
 205                 alarm_pending = 0;
 206                 spin_unlock_irqrestore(&alarm_slock, flags);
 207                 break;
 208         case ANDROID_ALARM_SET_RTC:
 209                 if (copy_from_user(&new_rtc_time, (void __user *)arg,
 210                     sizeof(new_rtc_time))) {
 211                         rv = -EFAULT;
 212                         goto err1;
 213                 }
 214                 rtc_time_to_tm(new_rtc_time.tv_sec, &new_rtc_tm);
 215                 rtc_dev = alarmtimer_get_rtcdev();
 216                 rv = do_settimeofday(&new_rtc_time);
 217                 if (rv < 0)
 218                         goto err1;
 219                 if (rtc_dev)
 220                         rv = rtc_set_time(rtc_dev, &new_rtc_tm);
 221                 spin_lock_irqsave(&alarm_slock, flags);
 222                 alarm_pending |= ANDROID_ALARM_TIME_CHANGE_MASK;
 223                 wake_up(&alarm_wait_queue);
 224                 spin_unlock_irqrestore(&alarm_slock, flags);
 225                 if (rv < 0)
 226                         goto err1;
 227                 break;
 228         case ANDROID_ALARM_GET_TIME(0):
 229                 switch (alarm_type) {
 230                 case ANDROID_ALARM_RTC_WAKEUP:
 231                 case ANDROID_ALARM_RTC:
 232                         getnstimeofday(&tmp_time);
 233                         break;
 234                 case ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP:
 235                 case ANDROID_ALARM_ELAPSED_REALTIME:
 236                         get_monotonic_boottime(&tmp_time);
 237                         break;
 238                 case ANDROID_ALARM_TYPE_COUNT:
 239                 case ANDROID_ALARM_SYSTEMTIME:
 240                         ktime_get_ts(&tmp_time);
 241                         break;
 242                 }
 243                 if (copy_to_user((void __user *)arg, &tmp_time,
 244                     sizeof(tmp_time))) {
 245                         rv = -EFAULT;
 246                         goto err1;
 247                 }
 248                 break;
 249
 250         default:
 251                 rv = -EINVAL;
 252                 goto err1;
 253         }
 254 err1:
 255         return rv;
 256 }
 257
 258 static int alarm_open(struct inode *inode, struct file *file)
 259 {
 260         file->private_data = NULL;
 261         return 0;
 262 }
 263
 264 static int alarm_release(struct inode *inode, struct file *file)
 265 {
 266         int i;
 267         unsigned long flags;
 268
 269         spin_lock_irqsave(&alarm_slock, flags);
 270         if (file->private_data != 0) {
 271                 for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++) {
 272                         uint32_t alarm_type_mask = 1U << i;
 273                         if (alarm_enabled & alarm_type_mask) {
 274                                 pr_alarm(INFO, "alarm_release: clear alarm, "
 275                                         "pending %d\n",
 276                                         !!(alarm_pending & alarm_type_mask));
 277                                 alarm_enabled &= ~alarm_type_mask;
 278                         }
 279                         spin_unlock_irqrestore(&alarm_slock, flags);
 280                         devalarm_cancel(&alarms[i]);
 281                         spin_lock_irqsave(&alarm_slock, flags);
 282                 }
 283                 if (alarm_pending | wait_pending) {
 284                         if (alarm_pending)
 285                                 pr_alarm(INFO, "alarm_release: clear "
 286                                         "pending alarms %x\n", alarm_pending);
 287                         wake_unlock(&alarm_wake_lock);
 288                         wait_pending = 0;
 289                         alarm_pending = 0;
 290                 }
 291                 alarm_opened = 0;
 292         }
 293         spin_unlock_irqrestore(&alarm_slock, flags);
 294         return 0;
 295 }
 296
 297 static void devalarm_triggered(struct devalarm *alarm)
 298 {
 299         unsigned long flags;
 300         uint32_t alarm_type_mask = 1U << alarm->type;
 301
 302         pr_alarm(INT, "devalarm_triggered type %d\n", alarm->type);
 303         spin_lock_irqsave(&alarm_slock, flags);
 304         if (alarm_enabled & alarm_type_mask) {
 305                 wake_lock_timeout(&alarm_wake_lock, 5 * HZ);
 306                 alarm_enabled &= ~alarm_type_mask;
 307                 alarm_pending |= alarm_type_mask;
 308                 wake_up(&alarm_wait_queue);
 309         }
 310         spin_unlock_irqrestore(&alarm_slock, flags);
 311 }
 312
 313
 314 static enum hrtimer_restart devalarm_hrthandler(struct hrtimer *hrt)
 315 {
 316         struct devalarm *devalrm = container_of(hrt, struct devalarm, u.hrt);
 317
 318         devalarm_triggered(devalrm);
 319         return HRTIMER_NORESTART;
 320 }
 321
 322 static enum alarmtimer_restart devalarm_alarmhandler(struct alarm *alrm,
 323                                                         ktime_t now)
 324 {
 325         struct devalarm *devalrm = container_of(alrm, struct devalarm, u.alrm);
 326
 327         devalarm_triggered(devalrm);
 328         return ALARMTIMER_NORESTART;
 329 }
 330
 331
 332 static const struct file_operations alarm_fops = {
 333         .owner = THIS_MODULE,
 334         .unlocked_ioctl = alarm_ioctl,
 335         .open = alarm_open,
 336         .release = alarm_release,
 337 };
 338
 339 static struct miscdevice alarm_device = {
 340         .minor = MISC_DYNAMIC_MINOR,
 341         .name = "alarm",
 342         .fops = &alarm_fops,
 343 };
 344
 345 static int __init alarm_dev_init(void)
 346 {
 347         int err;
 348         int i;
 349
 350         err = misc_register(&alarm_device);
 351         if (err)
 352                 return err;
 353
 354         alarm_init(&alarms[ANDROID_ALARM_RTC_WAKEUP].u.alrm,
 355                         ALARM_REALTIME, devalarm_alarmhandler);
 356         hrtimer_init(&alarms[ANDROID_ALARM_RTC].u.hrt,
 357                         CLOCK_REALTIME, HRTIMER_MODE_ABS);
 358         alarm_init(&alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP].u.alrm,
 359                         ALARM_BOOTTIME, devalarm_alarmhandler);
 360         hrtimer_init(&alarms[ANDROID_ALARM_ELAPSED_REALTIME].u.hrt,
 361                         CLOCK_BOOTTIME, HRTIMER_MODE_ABS);
 362         hrtimer_init(&alarms[ANDROID_ALARM_SYSTEMTIME].u.hrt,
 363                         CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 364
 365         for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++) {
 366                 alarms[i].type = i;
 367                 if (!is_wakeup(i))
 368                         alarms[i].u.hrt.function = devalarm_hrthandler;
 369         }
 370
 371         wake_lock_init(&alarm_wake_lock, WAKE_LOCK_SUSPEND, "alarm");
 372
 373         return 0;
 374 }
 375
 376 static void  __exit alarm_dev_exit(void)
 377 {
 378         misc_deregister(&alarm_device);
 379         wake_lock_destroy(&alarm_wake_lock);
 380 }
 381
 382 module_init(alarm_dev_init);
 383 module_exit(alarm_dev_exit);
 384