linux/drivers/base
Rafael J. Wysocki 704d2ce660 PM / domains: Rework governor code to be more consistent
The genpd governor currently uses negative PM QoS values to indicate
the "no suspend" condition and 0 as "no restriction", but it doesn't
use them consistently.  Moreover, it tries to refresh QoS values for
already suspended devices in a quite questionable way.

For the above reasons, rework it to be a bit more consistent.

First off, note that dev_pm_qos_read_value() in
dev_update_qos_constraint() and __default_power_down_ok() is
evaluated for devices in suspend.  Moreover, that only happens if the
effective_constraint_ns value for them is negative (meaning "no
suspend").  It is not evaluated in any other cases, so effectively
the QoS values are only updated for devices in suspend that should
not have been suspended in the first place.  In all of the other
cases, the QoS values taken into account are the effective ones from
the time before the device has been suspended, so generally devices
need to be resumed and suspended again for new QoS values to take
effect anyway.  Thus evaluating dev_update_qos_constraint() in
those two places doesn't make sense at all, so drop it.

Second, initialize effective_constraint_ns to 0 ("no constraint")
rather than to (-1) ("no suspend"), which makes more sense in
general and in case effective_constraint_ns is never updated
(the device is in suspend all the time or it is never suspended)
it doesn't affect the device's parent and so on.

Finally, rework default_suspend_ok() to explicitly handle the
"no restriction" and "no suspend" special cases.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Ramesh Thomas <ramesh.thomas@intel.com>
2017-11-08 12:13:13 +01:00
..
power PM / domains: Rework governor code to be more consistent 2017-11-08 12:13:13 +01:00
regmap regmap: regmap-w1: Fix build troubles 2017-07-17 15:53:00 +01:00
test driver core: test_async: fix up typo found by 0-day 2016-11-29 22:06:42 +01:00
arch_topology.c base: arch_topology: fix section mismatch build warnings 2017-09-18 17:05:07 +02:00
attribute_container.c attribute_container: Fix typo 2016-08-31 15:13:56 +02:00
base.h driver core: make device_{add|remove}_groups() public 2017-07-22 11:59:23 +02:00
bus.c driver core: bus: Fix a potential double free 2017-08-31 18:57:30 +02:00
cacheinfo.c Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-22 09:25:45 -08:00
class.c driver core: remove class_attrs from struct class 2017-06-09 10:41:00 +02:00
component.c Merge 4.5-rc4 into driver-core-next 2016-02-14 14:29:55 -08:00
container.c
core.c Do not disable driver and bus shutdown hook when class shutdown hook is set. 2017-08-28 18:02:46 +02:00
cpu.c treewide: make "nr_cpu_ids" unsigned 2017-09-08 18:26:48 -07:00
dd.c initcall_debug: add deferred probe times 2017-08-03 17:48:49 -07:00
devcoredump.c driver core: devcoredump: convert to use class_groups 2016-11-29 21:12:12 +01:00
devres.c devres: add devm_alloc_percpu() 2016-11-15 22:34:25 -05:00
devtmpfs.c statx: Add a system call to make enhanced file info available 2017-03-02 20:51:15 -05:00
dma-coherent.c dma-coherent: fix rmem_dma_device_init regression 2017-09-17 08:20:02 -07:00
dma-contiguous.c cma: Store a name in the cma structure 2017-04-18 20:41:12 +02:00
dma-mapping.c dma-coherent: remove the DMA_MEMORY_MAP and DMA_MEMORY_IO flags 2017-09-01 11:59:17 +02:00
driver.c driver core: add missing blank line after declaration 2015-03-25 14:36:30 +01:00
firmware_class.c Revert "firmware: add sanity check on shutdown/suspend" 2017-09-10 21:19:06 -07:00
firmware.c
hypervisor.c
init.c drivers: of/base: move of_init to driver_init 2015-05-26 19:55:56 -07:00
isa.c isa: Call isa_bus_init before dependent ISA bus drivers register 2016-06-17 20:47:11 -07:00
Kconfig firmware: Restore support for built-in firmware 2017-09-16 10:58:48 -07:00
Makefile arm, arm64: factorize common cpu capacity default code 2017-06-03 19:10:09 +09:00
map.c drivers: base: map: Use kmalloc_array instead of kmalloc 2015-03-25 14:35:08 +01:00
memory.c mm, memory_hotplug: remove zone restrictions 2017-09-06 17:27:25 -07:00
module.c base: make module_create_drivers_dir race-free 2016-06-15 19:21:31 -07:00
node.c mm: change the call sites of numa statistics items 2017-09-08 18:26:47 -07:00
pinctrl.c driver core: fix automatic pinctrl management 2017-06-13 11:07:32 +02:00
platform-msi.c irqchip/MSI: Use irq_domain_update_bus_token instead of an open coded access 2017-06-22 18:29:17 +02:00
platform.c driver core: platform: Don't read past the end of "driver_override" buffer 2017-09-18 17:16:47 +02:00
property.c device property: Introduce fwnode_property_get_reference_args 2017-07-22 00:04:51 +02:00
soc.c base: soc: Allow early registration of a single SoC device 2017-03-29 21:43:26 +02:00
syscore.c
topology.c base: topology: constify attribute_group structures. 2017-08-28 17:49:22 +02:00
transport_class.c