resume.c 2.0 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112
  1. /*
  2. * resume.c - Functions for waking devices up.
  3. *
  4. * Copyright (c) 2003 Patrick Mochel
  5. * Copyright (c) 2003 Open Source Development Labs
  6. *
  7. * This file is released under the GPLv2
  8. *
  9. */
  10. #include <linux/device.h>
  11. #include "power.h"
  12. extern int sysdev_resume(void);
  13. /**
  14. * resume_device - Restore state for one device.
  15. * @dev: Device.
  16. *
  17. */
  18. int resume_device(struct device * dev)
  19. {
  20. if (dev->bus && dev->bus->resume)
  21. return dev->bus->resume(dev);
  22. return 0;
  23. }
  24. void dpm_resume(void)
  25. {
  26. down(&dpm_list_sem);
  27. while(!list_empty(&dpm_off)) {
  28. struct list_head * entry = dpm_off.next;
  29. struct device * dev = to_device(entry);
  30. get_device(dev);
  31. list_del_init(entry);
  32. list_add_tail(entry, &dpm_active);
  33. up(&dpm_list_sem);
  34. if (!dev->power.prev_state)
  35. resume_device(dev);
  36. down(&dpm_list_sem);
  37. put_device(dev);
  38. }
  39. up(&dpm_list_sem);
  40. }
  41. /**
  42. * device_resume - Restore state of each device in system.
  43. *
  44. * Walk the dpm_off list, remove each entry, resume the device,
  45. * then add it to the dpm_active list.
  46. */
  47. void device_resume(void)
  48. {
  49. down(&dpm_sem);
  50. dpm_resume();
  51. up(&dpm_sem);
  52. }
  53. EXPORT_SYMBOL_GPL(device_resume);
  54. /**
  55. * device_power_up_irq - Power on some devices.
  56. *
  57. * Walk the dpm_off_irq list and power each device up. This
  58. * is used for devices that required they be powered down with
  59. * interrupts disabled. As devices are powered on, they are moved to
  60. * the dpm_suspended list.
  61. *
  62. * Interrupts must be disabled when calling this.
  63. */
  64. void dpm_power_up(void)
  65. {
  66. while(!list_empty(&dpm_off_irq)) {
  67. struct list_head * entry = dpm_off_irq.next;
  68. struct device * dev = to_device(entry);
  69. get_device(dev);
  70. list_del_init(entry);
  71. list_add_tail(entry, &dpm_active);
  72. resume_device(dev);
  73. put_device(dev);
  74. }
  75. }
  76. /**
  77. * device_pm_power_up - Turn on all devices that need special attention.
  78. *
  79. * Power on system devices then devices that required we shut them down
  80. * with interrupts disabled.
  81. * Called with interrupts disabled.
  82. */
  83. void device_power_up(void)
  84. {
  85. sysdev_resume();
  86. dpm_power_up();
  87. }
  88. EXPORT_SYMBOL_GPL(device_power_up);