kernel_optimize_test/drivers/base
Rafael J. Wysocki 9659cc0678 PM: Make system-wide PM and runtime PM treat subsystems consistently
The code handling system-wide power transitions (eg. suspend-to-RAM)
can in theory execute callbacks provided by the device's bus type,
device type and class in each phase of the power transition.  In
turn, the runtime PM core code only calls one of those callbacks at
a time, preferring bus type callbacks to device type or class
callbacks and device type callbacks to class callbacks.

It seems reasonable to make them both behave in the same way in that
respect.  Moreover, even though a device may belong to two subsystems
(eg. bus type and device class) simultaneously, in practice power
management callbacks for system-wide power transitions are always
provided by only one of them (ie. if the bus type callbacks are
defined, the device class ones are not and vice versa).  Thus it is
possible to modify the code handling system-wide power transitions
so that it follows the core runtime PM code (ie. treats the
subsystem callbacks as mutually exclusive).

On the other hand, the core runtime PM code will choose to execute,
for example, a runtime suspend callback provided by the device type
even if the bus type's struct dev_pm_ops object exists, but the
runtime_suspend pointer in it happens to be NULL.  This is confusing,
because it may lead to the execution of callbacks from different
subsystems during different operations (eg. the bus type suspend
callback may be executed during runtime suspend of the device, while
the device type callback will be executed during system suspend).

Make all of the power management code treat subsystem callbacks in
a consistent way, such that:
(1) If the device's type is defined (eg. dev->type is not NULL)
    and its pm pointer is not NULL, the callbacks from dev->type->pm
    will be used.
(2) If dev->type is NULL or dev->type->pm is NULL, but the device's
    class is defined (eg. dev->class is not NULL) and its pm pointer
    is not NULL, the callbacks from dev->class->pm will be used.
(3) If dev->type is NULL or dev->type->pm is NULL and dev->class is
    NULL or dev->class->pm is NULL, the callbacks from dev->bus->pm
    will be used provided that both dev->bus and dev->bus->pm are
    not NULL.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Kevin Hilman <khilman@ti.com>
Reasoning-sounds-sane-to: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-15 00:43:17 +01:00
..
power PM: Make system-wide PM and runtime PM treat subsystems consistently 2011-03-15 00:43:17 +01:00
attribute_container.c [SCSI] attirbute_container: Initialize sysfs attributes with sysfs_attr_init 2010-03-27 15:15:24 -04:00
base.h driver-core: merge private parts of class and bus 2010-11-17 14:21:08 -08:00
bus.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-01-13 10:05:56 -08:00
class.c driver-core: merge private parts of class and bus 2010-11-17 14:21:08 -08:00
core.c Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 2011-01-10 16:10:33 -08:00
cpu.c drivers/base/cpu.c: fix the output from /sys/devices/system/cpu/offline 2010-05-21 09:37:28 -07:00
dd.c Driver core: Add BUS_NOTIFY_BIND_DRIVER 2010-08-05 13:53:35 -07:00
devres.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
devtmpfs.c convert get_sb_single() users 2010-10-29 04:16:28 -04:00
dma-coherent.c Driver core: internal struct dma_coherent_mem, change type of a member. 2010-08-05 13:53:33 -07:00
dma-mapping.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
driver.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
firmware_class.c firmware_class: fix typo in error path 2010-08-23 18:12:46 -07:00
firmware.c firmware: change firmware_kset to firmware_kobj 2008-01-24 20:40:23 -08:00
hypervisor.c kobject: convert /sys/hypervisor to use kobject_create 2008-01-24 20:40:15 -08:00
init.c Driver Core: devtmpfs - kernel-maintained tmpfs-based /dev 2009-09-15 09:50:49 -07:00
iommu.c iommu-api: Remove iommu_{un}map_range functions 2010-03-07 18:01:13 +01:00
isa.c dma-mapping: replace all DMA_24BIT_MASK macro with DMA_BIT_MASK(24) 2009-04-07 08:31:12 -07:00
Kconfig kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
Makefile driver-core: base: change to new flag variable 2010-10-22 10:16:44 -07:00
map.c
memory.c Driver core: Add section count to memory_block struct 2010-10-22 10:16:44 -07:00
module.c driver core: module.c: Use kasprintf 2010-05-21 09:37:29 -07:00
node.c thp: transparent hugepage sysfs meminfo 2011-01-13 17:32:46 -08:00
platform.c Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6 2010-10-25 08:19:14 -07:00
sys.c driver core: Display error codes when class suspend fails 2010-10-22 10:16:44 -07:00
topology.c topology/sysfs: Provide book id and siblings attributes 2010-09-09 20:41:25 +02:00
transport_class.c SCSI: convert struct class_device to struct device 2008-04-19 19:10:33 -07:00