linux/drivers/base
Sudeep Holla 85945c28b5 PM / core: Add support to skip power management in device/driver model
All device objects in the driver model contain fields that control the
handling of various power management activities. However, it's not
always useful. There are few instances where pseudo devices are added
to the model just to take advantage of many other features like
kobjects, udev events, and so on. One such example is cpu devices and
their caches.

The sysfs for the cpu caches are managed by adding devices with cpu
as the parent in cpu_device_create() when secondary cpu is brought
online. Generally when the secondary CPUs are hotplugged back in as part
of resume from suspend-to-ram, we call cpu_device_create() from the cpu
hotplug state machine while the cpu device associated with that CPU is
not yet ready to be resumed as the device_resume() call happens bit
later. It's not really needed to set the flag is_prepared for cpu
devices as they are mostly pseudo device and hotplug framework deals
with state machine and not managed through the cpu device.

This often results in annoying warning when resuming:
Enabling non-boot CPUs ...
CPU1: Booted secondary processor
 cache: parent cpu1 should not be sleeping
CPU1 is up
CPU2: Booted secondary processor
 cache: parent cpu2 should not be sleeping
CPU2 is up
.... and so on.

So in order to fix these kind of errors, we could just completely avoid
doing any power management related initialisations and operations if
they are not used by these devices.

Add no_pm flags to indicate that the device doesn't require any sort of
PM activities and all of them can be completely skipped. We can use the
same flag to also avoid adding not used *power* sysfs entries for these
devices. For now, lets use this for cpu cache devices.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-02-19 10:42:43 +01:00
..
firmware_loader firmware: Always initialize the fw_priv list object 2018-09-30 08:49:55 -07:00
power PM / core: Add support to skip power management in device/driver model 2019-02-19 10:42:43 +01:00
regmap regmap-irq: do not write mask register if mask_base is zero 2019-01-14 22:11:22 +00:00
test driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
arch_topology.c sched/topology, drivers/base/arch_topology: Rebuild the sched_domain hierarchy when capacities change 2018-09-10 11:05:47 +02:00
attribute_container.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
base.h driver core: remove unnecessary function extern declare 2018-07-16 13:32:20 +02:00
bus.c sysfs: Disable lockdep for driver bind/unbind files 2018-12-19 15:58:40 +01:00
cacheinfo.c drivers: base: cacheinfo: Do not populate sysfs for unknown cache types 2018-10-04 23:02:17 +02:00
class.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
component.c component: convert to DEFINE_SHOW_ATTRIBUTE 2018-12-20 16:33:18 +01:00
container.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
core.c Driver core patches for 4.21-rc1 2018-12-28 20:44:29 -08:00
cpu.c PM / core: Add support to skip power management in device/driver model 2019-02-19 10:42:43 +01:00
dd.c driver core: Add missing dev->bus->need_parent_lock checks 2018-12-19 10:08:34 +01:00
devcon.c drivers: base: Unified device connection lookup 2018-03-22 13:10:29 +01:00
devcoredump.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
devres.c devres: Align data[] to ARCH_KMALLOC_MINALIGN 2018-11-11 11:40:04 -08:00
devtmpfs.c vfs: Suppress MS_* flag defs within the kernel unless explicitly enabled 2018-12-20 16:32:56 +00:00
driver.c driver-core: return EINVAL error instead of BUG_ON() 2018-05-25 18:18:45 +02:00
firmware.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
hypervisor.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
init.c base: fix order of OF initialization 2018-07-07 17:54:29 +02:00
isa.c Merge 4.15-rc3 into driver-core-next 2017-12-11 08:50:05 +01:00
Kconfig firmware_loader: move kconfig FW_LOADER entries to its own file 2018-05-14 16:43:10 +02:00
Makefile drivers: base: Introducing software nodes to the firmware node framework 2018-11-26 18:19:11 +01:00
map.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
memory.c Driver core patches for 4.21-rc1 2018-12-28 20:44:29 -08:00
module.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
node.c mm, proc: add KReclaimable to /proc/meminfo 2018-10-26 16:26:32 -07:00
pinctrl.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
platform-msi.c platform-msi: Free descriptors in platform_msi_domain_free() 2018-12-13 09:35:31 +00:00
platform.c drivers/base/platform.c: kmemleak ignore a known leak 2019-01-04 13:13:48 -08:00
property.c device property: fix fwnode_graph_get_next_endpoint() documentation 2018-12-18 23:39:45 +01:00
soc.c base: soc: use put_device() instead of kfree() 2018-03-15 14:37:03 +01:00
swnode.c drivers: base: swnode: check if swnode is NULL before dereferencing it 2018-12-26 10:50:36 +01:00
syscore.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
topology.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
transport_class.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00