Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * kernel/power/main.c - PM subsystem core functionality. |
| 3 | * |
| 4 | * Copyright (c) 2003 Patrick Mochel |
| 5 | * Copyright (c) 2003 Open Source Development Lab |
| 6 | * |
| 7 | * This file is released under the GPLv2 |
| 8 | * |
| 9 | */ |
| 10 | |
Ralf Baechle | 4cf3034 | 2006-12-06 20:36:06 -0800 | [diff] [blame] | 11 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/suspend.h> |
| 13 | #include <linux/kobject.h> |
| 14 | #include <linux/string.h> |
| 15 | #include <linux/delay.h> |
| 16 | #include <linux/errno.h> |
| 17 | #include <linux/init.h> |
Andrew Morton | 6cc0719 | 2006-06-22 14:47:18 -0700 | [diff] [blame] | 18 | #include <linux/console.h> |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 19 | #include <linux/cpu.h> |
Rafael J. Wysocki | c5c6ba4 | 2006-09-25 23:32:58 -0700 | [diff] [blame] | 20 | #include <linux/resume-trace.h> |
Nigel Cunningham | 7dfb710 | 2006-12-06 20:34:23 -0800 | [diff] [blame] | 21 | #include <linux/freezer.h> |
Christoph Lameter | 9617729 | 2007-02-10 01:43:03 -0800 | [diff] [blame] | 22 | #include <linux/vmstat.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | |
| 24 | #include "power.h" |
| 25 | |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 26 | BLOCKING_NOTIFIER_HEAD(pm_chain_head); |
| 27 | |
David Shaohua Li | 5ae947e | 2005-03-18 16:27:13 -0500 | [diff] [blame] | 28 | /*This is just an arbitrary number */ |
| 29 | #define FREE_PAGE_NUMBER (100) |
| 30 | |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 31 | DEFINE_MUTEX(pm_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
Pavel Machek | 123d3c1 | 2005-11-29 19:34:37 -0800 | [diff] [blame] | 33 | struct pm_ops *pm_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
| 35 | /** |
| 36 | * pm_set_ops - Set the global power method table. |
| 37 | * @ops: Pointer to ops structure. |
| 38 | */ |
| 39 | |
| 40 | void pm_set_ops(struct pm_ops * ops) |
| 41 | { |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 42 | mutex_lock(&pm_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | pm_ops = ops; |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 44 | mutex_unlock(&pm_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | } |
| 46 | |
Johannes Berg | e8c9c50 | 2007-04-30 15:09:54 -0700 | [diff] [blame] | 47 | /** |
| 48 | * pm_valid_only_mem - generic memory-only valid callback |
| 49 | * |
| 50 | * pm_ops drivers that implement mem suspend only and only need |
| 51 | * to check for that in their .valid callback can use this instead |
| 52 | * of rolling their own .valid callback. |
| 53 | */ |
| 54 | int pm_valid_only_mem(suspend_state_t state) |
| 55 | { |
| 56 | return state == PM_SUSPEND_MEM; |
| 57 | } |
| 58 | |
| 59 | |
Rafael J. Wysocki | e3c7db62 | 2007-02-10 01:43:31 -0800 | [diff] [blame] | 60 | static inline void pm_finish(suspend_state_t state) |
| 61 | { |
| 62 | if (pm_ops->finish) |
| 63 | pm_ops->finish(state); |
| 64 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | |
| 66 | /** |
| 67 | * suspend_prepare - Do prep work before entering low-power state. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | * |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 69 | * This is common code that is called for each state that we're entering. |
| 70 | * Run suspend notifiers, allocate a console and stop all processes. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | */ |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 72 | static int suspend_prepare(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | { |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 74 | int error; |
David Shaohua Li | 5ae947e | 2005-03-18 16:27:13 -0500 | [diff] [blame] | 75 | unsigned int free_pages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | |
| 77 | if (!pm_ops || !pm_ops->enter) |
| 78 | return -EPERM; |
| 79 | |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 80 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); |
| 81 | if (error) |
| 82 | goto Finish; |
| 83 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | pm_prepare_console(); |
| 85 | |
| 86 | if (freeze_processes()) { |
| 87 | error = -EAGAIN; |
| 88 | goto Thaw; |
| 89 | } |
| 90 | |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 91 | free_pages = global_page_state(NR_FREE_PAGES); |
| 92 | if (free_pages < FREE_PAGE_NUMBER) { |
David Shaohua Li | 5ae947e | 2005-03-18 16:27:13 -0500 | [diff] [blame] | 93 | pr_debug("PM: free some memory\n"); |
| 94 | shrink_all_memory(FREE_PAGE_NUMBER - free_pages); |
| 95 | if (nr_free_pages() < FREE_PAGE_NUMBER) { |
| 96 | error = -ENOMEM; |
| 97 | printk(KERN_ERR "PM: No enough memory\n"); |
David Shaohua Li | 5ae947e | 2005-03-18 16:27:13 -0500 | [diff] [blame] | 98 | } |
| 99 | } |
Rafael J. Wysocki | e3c7db62 | 2007-02-10 01:43:31 -0800 | [diff] [blame] | 100 | if (!error) |
| 101 | return 0; |
| 102 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | Thaw: |
| 104 | thaw_processes(); |
| 105 | pm_restore_console(); |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 106 | Finish: |
| 107 | pm_notifier_call_chain(PM_POST_SUSPEND); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | return error; |
| 109 | } |
| 110 | |
Johannes Berg | a53c46d | 2007-04-26 11:43:58 +0200 | [diff] [blame] | 111 | /* default implementation */ |
| 112 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) |
| 113 | { |
| 114 | local_irq_disable(); |
| 115 | } |
| 116 | |
| 117 | /* default implementation */ |
| 118 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) |
| 119 | { |
| 120 | local_irq_enable(); |
| 121 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 123 | /** |
| 124 | * suspend_enter - enter the desired system sleep state. |
| 125 | * @state: state to enter |
| 126 | * |
| 127 | * This function should be called after devices have been suspended. |
| 128 | */ |
Luca Tettamanti | 9b23820 | 2006-03-23 03:00:09 -0800 | [diff] [blame] | 129 | int suspend_enter(suspend_state_t state) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | { |
| 131 | int error = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | |
Johannes Berg | a53c46d | 2007-04-26 11:43:58 +0200 | [diff] [blame] | 133 | arch_suspend_disable_irqs(); |
| 134 | BUG_ON(!irqs_disabled()); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | |
| 136 | if ((error = device_power_down(PMSG_SUSPEND))) { |
| 137 | printk(KERN_ERR "Some devices failed to power down\n"); |
| 138 | goto Done; |
| 139 | } |
| 140 | error = pm_ops->enter(state); |
| 141 | device_power_up(); |
| 142 | Done: |
Johannes Berg | a53c46d | 2007-04-26 11:43:58 +0200 | [diff] [blame] | 143 | arch_suspend_enable_irqs(); |
| 144 | BUG_ON(irqs_disabled()); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | return error; |
| 146 | } |
| 147 | |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 148 | /** |
| 149 | * suspend_devices_and_enter - suspend devices and enter the desired system sleep |
| 150 | * state. |
| 151 | * @state: state to enter |
| 152 | */ |
| 153 | int suspend_devices_and_enter(suspend_state_t state) |
| 154 | { |
| 155 | int error; |
| 156 | |
| 157 | if (!pm_ops) |
| 158 | return -ENOSYS; |
| 159 | |
| 160 | if (pm_ops->set_target) { |
| 161 | error = pm_ops->set_target(state); |
| 162 | if (error) |
| 163 | return error; |
| 164 | } |
| 165 | suspend_console(); |
| 166 | error = device_suspend(PMSG_SUSPEND); |
| 167 | if (error) { |
| 168 | printk(KERN_ERR "Some devices failed to suspend\n"); |
| 169 | goto Resume_console; |
| 170 | } |
| 171 | if (pm_ops->prepare) { |
| 172 | error = pm_ops->prepare(state); |
| 173 | if (error) |
| 174 | goto Resume_devices; |
| 175 | } |
| 176 | error = disable_nonboot_cpus(); |
| 177 | if (!error) |
| 178 | suspend_enter(state); |
| 179 | |
| 180 | enable_nonboot_cpus(); |
| 181 | pm_finish(state); |
| 182 | Resume_devices: |
| 183 | device_resume(); |
| 184 | Resume_console: |
| 185 | resume_console(); |
| 186 | return error; |
| 187 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | |
| 189 | /** |
| 190 | * suspend_finish - Do final work before exiting suspend sequence. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | * |
| 192 | * Call platform code to clean up, restart processes, and free the |
| 193 | * console that we've allocated. This is not called for suspend-to-disk. |
| 194 | */ |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 195 | static void suspend_finish(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | thaw_processes(); |
| 198 | pm_restore_console(); |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 199 | pm_notifier_call_chain(PM_POST_SUSPEND); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | } |
| 201 | |
| 202 | |
| 203 | |
| 204 | |
Andreas Mohr | 3b364b8 | 2006-06-25 05:47:56 -0700 | [diff] [blame] | 205 | static const char * const pm_states[PM_SUSPEND_MAX] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | [PM_SUSPEND_STANDBY] = "standby", |
| 207 | [PM_SUSPEND_MEM] = "mem", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | }; |
| 209 | |
Pavel Machek | 123d3c1 | 2005-11-29 19:34:37 -0800 | [diff] [blame] | 210 | static inline int valid_state(suspend_state_t state) |
| 211 | { |
Rafael J. Wysocki | a3d25c2 | 2007-05-09 02:33:18 -0700 | [diff] [blame] | 212 | /* All states need lowlevel support and need to be valid |
| 213 | * to the lowlevel implementation, no valid callback |
Johannes Berg | 9684e51 | 2007-04-30 15:09:55 -0700 | [diff] [blame] | 214 | * implies that none are valid. */ |
| 215 | if (!pm_ops || !pm_ops->valid || !pm_ops->valid(state)) |
Pavel Machek | 123d3c1 | 2005-11-29 19:34:37 -0800 | [diff] [blame] | 216 | return 0; |
| 217 | return 1; |
| 218 | } |
| 219 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | |
| 221 | /** |
| 222 | * enter_state - Do common work of entering low-power state. |
| 223 | * @state: pm_state structure for state we're entering. |
| 224 | * |
| 225 | * Make sure we're the only ones trying to enter a sleep state. Fail |
| 226 | * if someone has beat us to it, since we don't want anything weird to |
| 227 | * happen when we wake up. |
| 228 | * Then, do the setup for suspend, enter the state, and cleaup (after |
| 229 | * we've woken up). |
| 230 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | static int enter_state(suspend_state_t state) |
| 232 | { |
| 233 | int error; |
| 234 | |
Pavel Machek | 123d3c1 | 2005-11-29 19:34:37 -0800 | [diff] [blame] | 235 | if (!valid_state(state)) |
Shaohua Li | eb9289e | 2005-10-30 15:00:01 -0800 | [diff] [blame] | 236 | return -ENODEV; |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 237 | if (!mutex_trylock(&pm_mutex)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | return -EBUSY; |
| 239 | |
David Brownell | 82428b6 | 2005-05-09 08:07:00 -0700 | [diff] [blame] | 240 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 241 | if ((error = suspend_prepare())) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | goto Unlock; |
| 243 | |
David Brownell | 82428b6 | 2005-05-09 08:07:00 -0700 | [diff] [blame] | 244 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 245 | error = suspend_devices_and_enter(state); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | |
David Brownell | 82428b6 | 2005-05-09 08:07:00 -0700 | [diff] [blame] | 247 | pr_debug("PM: Finishing wakeup.\n"); |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 248 | suspend_finish(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | Unlock: |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 250 | mutex_unlock(&pm_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | return error; |
| 252 | } |
| 253 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | |
| 255 | /** |
| 256 | * pm_suspend - Externally visible function for suspending system. |
Rafael J. Wysocki | a3d25c2 | 2007-05-09 02:33:18 -0700 | [diff] [blame] | 257 | * @state: Enumerated value of state to enter. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | * |
| 259 | * Determine whether or not value is within range, get state |
| 260 | * structure, and enter (above). |
| 261 | */ |
| 262 | |
| 263 | int pm_suspend(suspend_state_t state) |
| 264 | { |
Alexey Starikovskiy | e2a5b42 | 2005-03-18 16:20:46 -0500 | [diff] [blame] | 265 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | return enter_state(state); |
| 267 | return -EINVAL; |
| 268 | } |
| 269 | |
Ralf Baechle | 4cf3034 | 2006-12-06 20:36:06 -0800 | [diff] [blame] | 270 | EXPORT_SYMBOL(pm_suspend); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | |
| 272 | decl_subsys(power,NULL,NULL); |
| 273 | |
| 274 | |
| 275 | /** |
| 276 | * state - control system power state. |
| 277 | * |
| 278 | * show() returns what states are supported, which is hard-coded to |
| 279 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and |
| 280 | * 'disk' (Suspend-to-Disk). |
| 281 | * |
| 282 | * store() accepts one of those strings, translates it into the |
| 283 | * proper enumerated value, and initiates a suspend transition. |
| 284 | */ |
| 285 | |
Greg Kroah-Hartman | 823bccf | 2007-04-13 13:15:19 -0700 | [diff] [blame] | 286 | static ssize_t state_show(struct kset *kset, char *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 287 | { |
| 288 | int i; |
| 289 | char * s = buf; |
| 290 | |
| 291 | for (i = 0; i < PM_SUSPEND_MAX; i++) { |
Pavel Machek | 123d3c1 | 2005-11-29 19:34:37 -0800 | [diff] [blame] | 292 | if (pm_states[i] && valid_state(i)) |
| 293 | s += sprintf(s,"%s ", pm_states[i]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | } |
Rafael J. Wysocki | b0cb1a1 | 2007-07-29 23:24:36 +0200 | [diff] [blame^] | 295 | #ifdef CONFIG_HIBERNATION |
Rafael J. Wysocki | a3d25c2 | 2007-05-09 02:33:18 -0700 | [diff] [blame] | 296 | s += sprintf(s, "%s\n", "disk"); |
| 297 | #else |
| 298 | if (s != buf) |
| 299 | /* convert the last space to a newline */ |
| 300 | *(s-1) = '\n'; |
| 301 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | return (s - buf); |
| 303 | } |
| 304 | |
Greg Kroah-Hartman | 823bccf | 2007-04-13 13:15:19 -0700 | [diff] [blame] | 305 | static ssize_t state_store(struct kset *kset, const char *buf, size_t n) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | { |
| 307 | suspend_state_t state = PM_SUSPEND_STANDBY; |
Andreas Mohr | 3b364b8 | 2006-06-25 05:47:56 -0700 | [diff] [blame] | 308 | const char * const *s; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | char *p; |
| 310 | int error; |
| 311 | int len; |
| 312 | |
| 313 | p = memchr(buf, '\n', n); |
| 314 | len = p ? p - buf : n; |
| 315 | |
Rafael J. Wysocki | a3d25c2 | 2007-05-09 02:33:18 -0700 | [diff] [blame] | 316 | /* First, check if we are requested to hibernate */ |
Rafael J. Wysocki | 8d98a69 | 2007-05-16 22:11:19 -0700 | [diff] [blame] | 317 | if (len == 4 && !strncmp(buf, "disk", len)) { |
Rafael J. Wysocki | a3d25c2 | 2007-05-09 02:33:18 -0700 | [diff] [blame] | 318 | error = hibernate(); |
| 319 | return error ? error : n; |
| 320 | } |
| 321 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
Rafael J. Wysocki | 8d98a69 | 2007-05-16 22:11:19 -0700 | [diff] [blame] | 323 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | break; |
| 325 | } |
dean gaudet | 47bb789 | 2006-04-27 18:39:17 -0700 | [diff] [blame] | 326 | if (state < PM_SUSPEND_MAX && *s) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | error = enter_state(state); |
| 328 | else |
| 329 | error = -EINVAL; |
| 330 | return error ? error : n; |
| 331 | } |
| 332 | |
| 333 | power_attr(state); |
| 334 | |
Rafael J. Wysocki | c5c6ba4 | 2006-09-25 23:32:58 -0700 | [diff] [blame] | 335 | #ifdef CONFIG_PM_TRACE |
| 336 | int pm_trace_enabled; |
| 337 | |
Greg Kroah-Hartman | 823bccf | 2007-04-13 13:15:19 -0700 | [diff] [blame] | 338 | static ssize_t pm_trace_show(struct kset *kset, char *buf) |
Rafael J. Wysocki | c5c6ba4 | 2006-09-25 23:32:58 -0700 | [diff] [blame] | 339 | { |
| 340 | return sprintf(buf, "%d\n", pm_trace_enabled); |
| 341 | } |
| 342 | |
| 343 | static ssize_t |
Greg Kroah-Hartman | 823bccf | 2007-04-13 13:15:19 -0700 | [diff] [blame] | 344 | pm_trace_store(struct kset *kset, const char *buf, size_t n) |
Rafael J. Wysocki | c5c6ba4 | 2006-09-25 23:32:58 -0700 | [diff] [blame] | 345 | { |
| 346 | int val; |
| 347 | |
| 348 | if (sscanf(buf, "%d", &val) == 1) { |
| 349 | pm_trace_enabled = !!val; |
| 350 | return n; |
| 351 | } |
| 352 | return -EINVAL; |
| 353 | } |
| 354 | |
| 355 | power_attr(pm_trace); |
| 356 | |
| 357 | static struct attribute * g[] = { |
| 358 | &state_attr.attr, |
| 359 | &pm_trace_attr.attr, |
| 360 | NULL, |
| 361 | }; |
| 362 | #else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | static struct attribute * g[] = { |
| 364 | &state_attr.attr, |
| 365 | NULL, |
| 366 | }; |
Rafael J. Wysocki | c5c6ba4 | 2006-09-25 23:32:58 -0700 | [diff] [blame] | 367 | #endif /* CONFIG_PM_TRACE */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | |
| 369 | static struct attribute_group attr_group = { |
| 370 | .attrs = g, |
| 371 | }; |
| 372 | |
| 373 | |
| 374 | static int __init pm_init(void) |
| 375 | { |
| 376 | int error = subsystem_register(&power_subsys); |
| 377 | if (!error) |
Greg Kroah-Hartman | 823bccf | 2007-04-13 13:15:19 -0700 | [diff] [blame] | 378 | error = sysfs_create_group(&power_subsys.kobj,&attr_group); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | return error; |
| 380 | } |
| 381 | |
| 382 | core_initcall(pm_init); |