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-rw-r--r--Documentation/power/devices.txt34
1 files changed, 5 insertions, 29 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt
index 421e7d00ffd0..c9abbd86bc18 100644
--- a/Documentation/power/devices.txt
+++ b/Documentation/power/devices.txt
@@ -75,9 +75,6 @@ may need to apply in domain-specific ways to their devices:
75struct bus_type { 75struct bus_type {
76 ... 76 ...
77 int (*suspend)(struct device *dev, pm_message_t state); 77 int (*suspend)(struct device *dev, pm_message_t state);
78 int (*suspend_late)(struct device *dev, pm_message_t state);
79
80 int (*resume_early)(struct device *dev);
81 int (*resume)(struct device *dev); 78 int (*resume)(struct device *dev);
82}; 79};
83 80
@@ -226,20 +223,7 @@ The phases are seen by driver notifications issued in this order:
226 223
227 This call should handle parts of device suspend logic that require 224 This call should handle parts of device suspend logic that require
228 sleeping. It probably does work to quiesce the device which hasn't 225 sleeping. It probably does work to quiesce the device which hasn't
229 been abstracted into class.suspend() or bus.suspend_late(). 226 been abstracted into class.suspend().
230
231 3 bus.suspend_late(dev, message) is called with IRQs disabled, and
232 with only one CPU active. Until the bus.resume_early() phase
233 completes (see later), IRQs are not enabled again. This method
234 won't be exposed by all busses; for message based busses like USB,
235 I2C, or SPI, device interactions normally require IRQs. This bus
236 call may be morphed into a driver call with bus-specific parameters.
237
238 This call might save low level hardware state that might otherwise
239 be lost in the upcoming low power state, and actually put the
240 device into a low power state ... so that in some cases the device
241 may stay partly usable until this late. This "late" call may also
242 help when coping with hardware that behaves badly.
243 227
244The pm_message_t parameter is currently used to refine those semantics 228The pm_message_t parameter is currently used to refine those semantics
245(described later). 229(described later).
@@ -351,19 +335,11 @@ devices processing each phase's calls before the next phase begins.
351 335
352The phases are seen by driver notifications issued in this order: 336The phases are seen by driver notifications issued in this order:
353 337
354 1 bus.resume_early(dev) is called with IRQs disabled, and with 338 1 bus.resume(dev) reverses the effects of bus.suspend(). This may
355 only one CPU active. As with bus.suspend_late(), this method 339 be morphed into a device driver call with bus-specific parameters;
356 won't be supported on busses that require IRQs in order to 340 implementations may sleep.
357 interact with devices.
358
359 This reverses the effects of bus.suspend_late().
360
361 2 bus.resume(dev) is called next. This may be morphed into a device
362 driver call with bus-specific parameters; implementations may sleep.
363
364 This reverses the effects of bus.suspend().
365 341
366 3 class.resume(dev) is called for devices associated with a class 342 2 class.resume(dev) is called for devices associated with a class
367 that has such a method. Implementations may sleep. 343 that has such a method. Implementations may sleep.
368 344
369 This reverses the effects of class.suspend(), and would usually 345 This reverses the effects of class.suspend(), and would usually