target/linux/goldfish/patches-2.6.30/0069-PM-Add-user-space-wake-lock-api.patch

   1 From 48e1af2bdd11204f11b3770a6c8d3eee64aee2e8 Mon Sep 17 00:00:00 2001
   2 From: =?utf-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= <arve@android.com>
   3 Date: Thu, 9 Oct 2008 21:01:46 -0700
   4 Subject: [PATCH 069/134] PM: Add user-space wake lock api.
   5
   6 This adds /sys/power/wake_lock and /sys/power/wake_unlock.
   7 Writing a string to wake_lock creates a wake lock the
   8 first time is sees a string and locks it. Optionally, the
   9 string can be followed by a timeout.
  10 To unlock the wake lock, write the same string to wake_unlock.
  11 ---
  12  kernel/power/Kconfig        |   10 ++
  13  kernel/power/Makefile       |    1 +
  14  kernel/power/main.c         |    9 ++
  15  kernel/power/power.h        |   11 ++
  16  kernel/power/userwakelock.c |  218 +++++++++++++++++++++++++++++++++++++++++++
  17  5 files changed, 249 insertions(+), 0 deletions(-)
  18  create mode 100644 kernel/power/userwakelock.c
  19
  20 --- a/kernel/power/Kconfig
  21 +++ b/kernel/power/Kconfig
  22 @@ -138,6 +138,16 @@ config WAKELOCK_STAT
  23         ---help---
  24           Report wake lock stats in /proc/wakelocks
  25
  26 +config USER_WAKELOCK
  27 +       bool "Userspace wake locks"
  28 +       depends on WAKELOCK
  29 +       default y
  30 +       ---help---
  31 +         User-space wake lock api. Write "lockname" or "lockname timeout"
  32 +         to /sys/power/wake_lock lock and if needed create a wake lock.
  33 +         Write "lockname" to /sys/power/wake_unlock to unlock a user wake
  34 +         lock.
  35 +
  36  config EARLYSUSPEND
  37         bool "Early suspend"
  38         depends on WAKELOCK
  39 --- a/kernel/power/Makefile
  40 +++ b/kernel/power/Makefile
  41 @@ -7,6 +7,7 @@ obj-$(CONFIG_PM)                += main.o
  42  obj-$(CONFIG_PM_SLEEP)         += console.o
  43  obj-$(CONFIG_FREEZER)          += process.o
  44  obj-$(CONFIG_WAKELOCK)         += wakelock.o
  45 +obj-$(CONFIG_USER_WAKELOCK)    += userwakelock.o
  46  obj-$(CONFIG_EARLYSUSPEND)     += earlysuspend.o
  47  obj-$(CONFIG_HIBERNATION)      += swsusp.o disk.o snapshot.o swap.o user.o
  48
  49 --- a/kernel/power/main.c
  50 +++ b/kernel/power/main.c
  51 @@ -595,6 +595,11 @@ pm_trace_store(struct kobject *kobj, str
  52  power_attr(pm_trace);
  53  #endif /* CONFIG_PM_TRACE */
  54
  55 +#ifdef CONFIG_USER_WAKELOCK
  56 +power_attr(wake_lock);
  57 +power_attr(wake_unlock);
  58 +#endif
  59 +
  60  static struct attribute * g[] = {
  61         &state_attr.attr,
  62  #ifdef CONFIG_PM_TRACE
  63 @@ -603,6 +608,10 @@ static struct attribute * g[] = {
  64  #if defined(CONFIG_PM_SLEEP) && defined(CONFIG_PM_DEBUG)
  65         &pm_test_attr.attr,
  66  #endif
  67 +#ifdef CONFIG_USER_WAKELOCK
  68 +       &wake_lock_attr.attr,
  69 +       &wake_unlock_attr.attr,
  70 +#endif
  71         NULL,
  72  };
  73
  74 --- a/kernel/power/power.h
  75 +++ b/kernel/power/power.h
  76 @@ -231,6 +231,17 @@ extern struct wake_lock main_wake_lock;
  77  extern suspend_state_t requested_suspend_state;
  78  #endif
  79
  80 +#ifdef CONFIG_USER_WAKELOCK
  81 +ssize_t wake_lock_show(struct kobject *kobj, struct kobj_attribute *attr,
  82 +                       char *buf);
  83 +ssize_t wake_lock_store(struct kobject *kobj, struct kobj_attribute *attr,
  84 +                       const char *buf, size_t n);
  85 +ssize_t wake_unlock_show(struct kobject *kobj, struct kobj_attribute *attr,
  86 +                       char *buf);
  87 +ssize_t  wake_unlock_store(struct kobject *kobj, struct kobj_attribute *attr,
  88 +                       const char *buf, size_t n);
  89 +#endif
  90 +
  91  #ifdef CONFIG_EARLYSUSPEND
  92  /* kernel/power/earlysuspend.c */
  93  void request_suspend_state(suspend_state_t state);
  94 --- /dev/null
  95 +++ b/kernel/power/userwakelock.c
  96 @@ -0,0 +1,218 @@
  97 +/* kernel/power/userwakelock.c
  98 + *
  99 + * Copyright (C) 2005-2008 Google, Inc.
 100 + *
 101 + * This software is licensed under the terms of the GNU General Public
 102 + * License version 2, as published by the Free Software Foundation, and
 103 + * may be copied, distributed, and modified under those terms.
 104 + *
 105 + * This program is distributed in the hope that it will be useful,
 106 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
 107 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 108 + * GNU General Public License for more details.
 109 + *
 110 + */
 111 +
 112 +#include <linux/ctype.h>
 113 +#include <linux/module.h>
 114 +#include <linux/wakelock.h>
 115 +
 116 +#include "power.h"
 117 +
 118 +enum {
 119 +       DEBUG_FAILURE   = BIT(0),
 120 +       DEBUG_ERROR     = BIT(1),
 121 +       DEBUG_NEW       = BIT(2),
 122 +       DEBUG_ACCESS    = BIT(3),
 123 +       DEBUG_LOOKUP    = BIT(4),
 124 +};
 125 +static int debug_mask = DEBUG_FAILURE;
 126 +module_param_named(debug_mask, debug_mask, int, S_IRUGO | S_IWUSR | S_IWGRP);
 127 +
 128 +static DEFINE_MUTEX(tree_lock);
 129 +
 130 +struct user_wake_lock {
 131 +       struct rb_node          node;
 132 +       struct wake_lock        wake_lock;
 133 +       char                    name[0];
 134 +};
 135 +struct rb_root user_wake_locks;
 136 +
 137 +static struct user_wake_lock *lookup_wake_lock_name(
 138 +       const char *buf, int allocate, long *timeoutptr)
 139 +{
 140 +       struct rb_node **p = &user_wake_locks.rb_node;
 141 +       struct rb_node *parent = NULL;
 142 +       struct user_wake_lock *l;
 143 +       int diff;
 144 +       u64 timeout;
 145 +       int name_len;
 146 +       const char *arg;
 147 +
 148 +       /* Find length of lock name and start of optional timeout string */
 149 +       arg = buf;
 150 +       while (*arg && !isspace(*arg))
 151 +               arg++;
 152 +       name_len = arg - buf;
 153 +       if (!name_len)
 154 +               goto bad_arg;
 155 +       while (isspace(*arg))
 156 +               arg++;
 157 +
 158 +       /* Process timeout string */
 159 +       if (timeoutptr && *arg) {
 160 +               timeout = simple_strtoull(arg, (char **)&arg, 0);
 161 +               while (isspace(*arg))
 162 +                       arg++;
 163 +               if (*arg)
 164 +                       goto bad_arg;
 165 +               /* convert timeout from nanoseconds to jiffies > 0 */
 166 +               timeout += (NSEC_PER_SEC / HZ) - 1;
 167 +               do_div(timeout, (NSEC_PER_SEC / HZ));
 168 +               if (timeout <= 0)
 169 +                       timeout = 1;
 170 +               *timeoutptr = timeout;
 171 +       } else if (*arg)
 172 +               goto bad_arg;
 173 +       else if (timeoutptr)
 174 +               *timeoutptr = 0;
 175 +
 176 +       /* Lookup wake lock in rbtree */
 177 +       while (*p) {
 178 +               parent = *p;
 179 +               l = rb_entry(parent, struct user_wake_lock, node);
 180 +               diff = strncmp(buf, l->name, name_len);
 181 +               if (!diff && l->name[name_len])
 182 +                       diff = -1;
 183 +               if (debug_mask & DEBUG_ERROR)
 184 +                       pr_info("lookup_wake_lock_name: compare %.*s %s %d\n",
 185 +                               name_len, buf, l->name, diff);
 186 +
 187 +               if (diff < 0)
 188 +                       p = &(*p)->rb_left;
 189 +               else if (diff > 0)
 190 +                       p = &(*p)->rb_right;
 191 +               else
 192 +                       return l;
 193 +       }
 194 +
 195 +       /* Allocate and add new wakelock to rbtree */
 196 +       if (!allocate) {
 197 +               if (debug_mask & DEBUG_ERROR)
 198 +                       pr_info("lookup_wake_lock_name: %.*s not found\n",
 199 +                               name_len, buf);
 200 +               return ERR_PTR(-EINVAL);
 201 +       }
 202 +       l = kzalloc(sizeof(*l) + name_len + 1, GFP_KERNEL);
 203 +       if (l == NULL) {
 204 +               if (debug_mask & DEBUG_FAILURE)
 205 +                       pr_err("lookup_wake_lock_name: failed to allocate "
 206 +                               "memory for %.*s\n", name_len, buf);
 207 +               return ERR_PTR(-ENOMEM);
 208 +       }
 209 +       memcpy(l->name, buf, name_len);
 210 +       if (debug_mask & DEBUG_NEW)
 211 +               pr_info("lookup_wake_lock_name: new wake lock %s\n", l->name);
 212 +       wake_lock_init(&l->wake_lock, WAKE_LOCK_SUSPEND, l->name);
 213 +       rb_link_node(&l->node, parent, p);
 214 +       rb_insert_color(&l->node, &user_wake_locks);
 215 +       return l;
 216 +
 217 +bad_arg:
 218 +       if (debug_mask & DEBUG_ERROR)
 219 +               pr_info("lookup_wake_lock_name: wake lock, %.*s, bad arg, %s\n",
 220 +                       name_len, buf, arg);
 221 +       return ERR_PTR(-EINVAL);
 222 +}
 223 +
 224 +ssize_t wake_lock_show(
 225 +       struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 226 +{
 227 +       char *s = buf;
 228 +       char *end = buf + PAGE_SIZE;
 229 +       struct rb_node *n;
 230 +       struct user_wake_lock *l;
 231 +
 232 +       mutex_lock(&tree_lock);
 233 +
 234 +       for (n = rb_first(&user_wake_locks); n != NULL; n = rb_next(n)) {
 235 +               l = rb_entry(n, struct user_wake_lock, node);
 236 +               if (wake_lock_active(&l->wake_lock))
 237 +                       s += scnprintf(s, end - s, "%s ", l->name);
 238 +       }
 239 +       s += scnprintf(s, end - s, "\n");
 240 +
 241 +       mutex_unlock(&tree_lock);
 242 +       return (s - buf);
 243 +}
 244 +
 245 +ssize_t wake_lock_store(
 246 +       struct kobject *kobj, struct kobj_attribute *attr,
 247 +       const char *buf, size_t n)
 248 +{
 249 +       long timeout;
 250 +       struct user_wake_lock *l;
 251 +
 252 +       mutex_lock(&tree_lock);
 253 +       l = lookup_wake_lock_name(buf, 1, &timeout);
 254 +       if (IS_ERR(l)) {
 255 +               n = PTR_ERR(l);
 256 +               goto bad_name;
 257 +       }
 258 +
 259 +       if (debug_mask & DEBUG_ACCESS)
 260 +               pr_info("wake_lock_store: %s, timeout %ld\n", l->name, timeout);
 261 +
 262 +       if (timeout)
 263 +               wake_lock_timeout(&l->wake_lock, timeout);
 264 +       else
 265 +               wake_lock(&l->wake_lock);
 266 +bad_name:
 267 +       mutex_unlock(&tree_lock);
 268 +       return n;
 269 +}
 270 +
 271 +
 272 +ssize_t wake_unlock_show(
 273 +       struct kobject *kobj, struct kobj_attribute *attr, char *buf)
 274 +{
 275 +       char *s = buf;
 276 +       char *end = buf + PAGE_SIZE;
 277 +       struct rb_node *n;
 278 +       struct user_wake_lock *l;
 279 +
 280 +       mutex_lock(&tree_lock);
 281 +
 282 +       for (n = rb_first(&user_wake_locks); n != NULL; n = rb_next(n)) {
 283 +               l = rb_entry(n, struct user_wake_lock, node);
 284 +               if (!wake_lock_active(&l->wake_lock))
 285 +                       s += scnprintf(s, end - s, "%s ", l->name);
 286 +       }
 287 +       s += scnprintf(s, end - s, "\n");
 288 +
 289 +       mutex_unlock(&tree_lock);
 290 +       return (s - buf);
 291 +}
 292 +
 293 +ssize_t wake_unlock_store(
 294 +       struct kobject *kobj, struct kobj_attribute *attr,
 295 +       const char *buf, size_t n)
 296 +{
 297 +       struct user_wake_lock *l;
 298 +
 299 +       mutex_lock(&tree_lock);
 300 +       l = lookup_wake_lock_name(buf, 0, NULL);
 301 +       if (IS_ERR(l)) {
 302 +               n = PTR_ERR(l);
 303 +               goto not_found;
 304 +       }
 305 +
 306 +       if (debug_mask & DEBUG_ACCESS)
 307 +               pr_info("wake_unlock_store: %s\n", l->name);
 308 +
 309 +       wake_unlock(&l->wake_lock);
 310 +not_found:
 311 +       mutex_unlock(&tree_lock);
 312 +       return n;
 313 +}
 314 +