Currently cpuidle drivers are spread across different archs.

As a result, there are several different paths for cpuidle patch
submissions: cpuidle core changes go through linux-pm, ARM driver
changes go to the arm-soc or SoC-specific trees, sh changes go
through the sh arch tree, pseries changes go through the PowerPC tree
and finally intel changes go through the Len's tree while ACPI idle
changes go through linux-pm.

That makes it difficult to consolidate code and to propagate
modifications from the cpuidle core to the different drivers.

Hopefully, a movement has started to put the majority of cpuidle
drivers under drivers/cpuidle like cpuidle-calxeda.c and
cpuidle-kirkwood.c.

Add a maintainer entry for cpuidle to MAINTAINERS to clarify the
situation and to indicate to new cpuidle driver authors that those
drivers should not go into arch-specific directories.

The upstreaming process is unchanged: Rafael takes patches for
merging into his tree, but with an Acked-by: tag from the driver's
maintainer, so indicate in the drivers' headers who maintains them.

The arrangement will be the same as for cpufreq.

[rjw: Changelog]
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andrew Lunn <andrew@lunn.ch>  #for kirkwood
Acked-by: Jason Cooper <jason@lakedaemon.net> #for kirkwood
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Fix comment format for the kernel doc script.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The code intializes the cpuidle driver at different places.
The cpuidle driver for :
  * imx5 : is in the pm-imx5.c, the init function is in cpuidle.c
  * imx6 : is in cpuidle-imx6q.c, the init function is in cpuidle.c
           and cpuidle-imx6q.c

Instead of having the cpuidle code spread across different files,
let's create a driver for each SoC and use the common register function.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicated code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the duplicate code and use the cpuidle common code for initialization.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The usual scheme to initialize a cpuidle driver on a SMP is:

	cpuidle_register_driver(drv);
	for_each_possible_cpu(cpu) {
		device = &per_cpu(cpuidle_dev, cpu);
		cpuidle_register_device(device);
	}

This code is duplicated in each cpuidle driver.

On UP systems, it is done this way:

	cpuidle_register_driver(drv);
	device = &per_cpu(cpuidle_dev, cpu);
	cpuidle_register_device(device);

On UP, the macro 'for_each_cpu' does one iteration:

#define for_each_cpu(cpu, mask)                 \
        for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)

Hence, the initialization loop is the same for UP than SMP.

Beside, we saw different bugs / mis-initialization / return code unchecked in
the different drivers, the code is duplicated including bugs. After fixing all
these ones, it appears the initialization pattern is the same for everyone.

Please note, some drivers are doing dev->state_count = drv->state_count. This is
not necessary because it is done by the cpuidle_enable_device function in the
cpuidle framework. This is true, until you have the same states for all your
devices. Otherwise, the 'low level' API should be used instead with the specific
initialization for the driver.

Let's add a wrapper function doing this initialization with a cpumask parameter
for the coupled idle states and use it for all the drivers.

That will save a lot of LOC, consolidate the code, and the modifications in the
future could be done in a single place. Another benefit is the consolidation of
the cpuidle_device variable which is now in the cpuidle framework and no longer
spread accross the different arch specific drivers.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

All the drivers are using, in their initialization function, the
for_each_possible_cpu macro.

Using for_each_online_cpu means the driver must handle the initialization
of the cpuidle device when a cpu is up which is not the case here.

Change the macro to for_each_possible_cpu as that fix the hotplug
initialization and make the initialization routine consistent with the
rest of the code in the different drivers.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The en_core_tk_irqen flag is set in all the cpuidle driver which
means it is not necessary to specify this flag.

Remove the flag and the code related to it.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>  # for mach-omap2/*
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

In a previous commit the en_core_tk_irqen flag has been added but we missed
the cpuidle_wrap_enter which was doing the job to measure the time for the
'omap3_enter_idle' function.

Actually, I don't see any reason to use this wrapper in the code. In the better
case, the time computation is not correctly done because of the different
operations done in omap3_enter_idle_bm which were not taken into account
before the en_core_tk_irqen flag was set.

As the time is reflected for the state overridden by the omap3_enter_idle_bm,
using the wrapper is pointless now, so removing it.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 688036b5 removed the function
'shmobile_enter_wfi' but we forgot to remove the definition in the header file.

Note this function is just an alias to 'cpu_do_idle()' wrapped into a cpuidle
function callback prototype which already exists with the default WFI state
and the arm_simple_enter function.

Remove the function prototype.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the shmobile_enter_wfi function which is the same as the
common WFI enter function from the arm cpuidle driver defined
with the ARM_CPUIDLE_WFI_STATE macro.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Registering the driver, or the device, can fail, let's check the return code
and return the error code to the PM layer.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Like all the other drivers, let's initialize the structure a compile time
instead of init time.

The states #1 and #2 are not enabled by default. The init function will
check the features of the board in order to enable the state.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The CPUIDLE_DRIVER_STATE_START constant is only set when the kernel compilation
option CONFIG_ARCH_HAS_CPU_RELAX is set, but this is only relatated to x86, so
it is always zero.

Remove the reference to this constant in the code.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The driver is a global static variable automatically initialized to zero.

Removing the useless initialization in the init function.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The start/stop_critical_timings are called from arch/x86/kernel/process.c
in the cpu_idle loop function.

Remove the ones in the cpuidle driver.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Merge tag 'omap-pm-v3.10/cleanup/cpuidle-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm into pm-cpuidle

OMAP CPUidle cleanups for v3.10 from Kevin Hilman

The OMAP5 idle driver can re-use most of OMAP4 CPUidle driver
implementation. Also the next derivative SOCs are going to re-use
the MPUSS so, same driver with minor updates can be re-used.

Prepare the code so that its easier to add CPUidle support for
OMAP5 devices.
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>

Current OMAP4 CPUIdle driver is using omap4_mpuss_read_prev_context_state()
to check whether the MPU cluster lost context or not before calling
cpu_cluster_pm_exit().  This was initially done an optimization for
corner cases, where if the cluster low power entry fails for some
reason, the cluster context restore gets skipped.  However, since
reading the previous context is expensive (involving slow accesses to
the PRCM), it's better to avoid it and simply check the target cluster
state instead.

Moving forward, OMAP CPUidle drivers needs to be moved to drivers/idle/*
once the PRM/CM code gets moved to drivers. This patch also reduces one
dependency with platform code for idle driver movement.
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[khilman@linaro.org: minor changelog edits]
Signed-off-by: Kevin Hilman <khilman@linaro.org>

It is useful to know the CPU power state along with MPUSS power state
in a supported C-state. Since the data is available via sysfs, one can
avoid scrolling the source code for precise construction of C-state.
Reported-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>

If the CPUidle device registration fails for some reason, we should
unregister the driver on error path.

Fix the code accordingly. Also when at it, check of the driver registration
failure too.
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>

OMAP4 CPUidle driver registration call is under a loop which leads
to calling cpuidle_register_driver twice which is not intended.

Fix it by moving the driver registration outside the loop.
Reported-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>

The TIME_VALID flag is specified for the different states but
the time residency computation is not done, no tk flag, no time
computation in the idle function.

Set the en_core_tk_irqen flag to activate it.

Cc: stable@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@linaro.org>

The current code computes the idle time but that can be handled
by the cpuidle framework if we enable the .en_core_tk_irqen flag.

Set the flag and remove the code related to the time computation.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The TIME_VALID flag is specified for the different states but
the time residency computation is not done, no tk flag, no time
computation in the idle function.

Set the en_core_tk_irqen flag to activate it.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The davinci_enter_idle is called from the cpuidle with the
cpuidle_wrap_enter function. This one does the time compution
for entering and exiting the idle function and then we call
again cpuidle_wrap_enter for cpu_do_idle. This is wrong, we
are calling recursively cpuidle_wrap_enter for nothing and
furthermore reenabling the local irq.

Remove this and replace it by the cpu_do_idle function.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

dev->state_count is initialized automatically by
cpuidle_register_device().

When drv->state_count is equal to dev->state_count, no need to init
this field, so removing it.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Initialize the idle states directly in the driver structure.

That prevents extra structure declaration and memcpy at init time.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Remove the shmobile_enter_wfi function which is the same as the
common WFI enter function from the arm cpuidle driver defined
with the ARM_CPUIDLE_WFI_STATE macro.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>