linux-toradex.git/drivers/cpuidle, branch v3.10.2

cpuidle: add maintainer entry

2013-04-26T20:30:25+00:00

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 
Acked-by: Linus Walleij 
Acked-by: Andrew Lunn   #for kirkwood
Acked-by: Jason Cooper  #for kirkwood
Acked-by: Kevin Hilman 
Signed-off-by: Rafael J. Wysocki

cpuidle: fix comment format

2013-04-23T22:54:51+00:00

Fix comment format for the kernel doc script.

Signed-off-by: Daniel Lezcano 
Signed-off-by: Rafael J. Wysocki

ARM: kirkwood: cpuidle: use init/exit common routine

2013-04-23T11:45:23+00:00

Remove the duplicated code and use the cpuidle common code for initialization.

Signed-off-by: Daniel Lezcano 
Tested-by: Andrew Lunn 
Acked-by: Andrew Lunn 
Signed-off-by: Rafael J. Wysocki

ARM: calxeda: cpuidle: use init/exit common routine

2013-04-23T11:45:23+00:00

Remove the duplicated code and use the cpuidle common code for initialization.

Signed-off-by: Daniel Lezcano 
Acked-by: Rob Herring 
Signed-off-by: Rafael J. Wysocki

cpuidle: make a single register function for all

2013-04-23T11:45:22+00:00

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 
Signed-off-by: Rafael J. Wysocki

cpuidle: remove en_core_tk_irqen flag

2013-04-23T11:45:22+00:00

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 
Acked-by: Kevin Hilman   # for mach-omap2/*
Signed-off-by: Rafael J. Wysocki

cpuidle: initialize the broadcast timer framework

2013-03-31T23:10:28+00:00

The commit 89878baa73f0f1c679355006bd8632e5d78f96c2 introduced
the CPUIDLE_FLAG_TIMER_STOP flag where we specify a specific idle
state stops the local timer.

Now use this flag to check at init time if one state will need
the broadcast timer and, in this case, setup the broadcast timer
framework. That prevents multiple code duplication in the drivers.

Signed-off-by: Daniel Lezcano 
Signed-off-by: Rafael J. Wysocki

cpuidle: kirkwood: fix coccicheck warnings

2013-03-31T23:10:27+00:00

Convert all uses of devm_request_and_ioremap() to the newly introduced
devm_ioremap_resource() which provides more consistent error handling.

devm_ioremap_resource() provides its own error messages so all explicit
error messages can be removed from the failure code paths.

Signed-off-by: Silviu-Mihai Popescu 
Reviewed-by: Daniel Lezcano 
Signed-off-by: Rafael J. Wysocki

cpuidle / kirkwood: remove redundant Kconfig option

2013-03-31T23:10:27+00:00

When the CPU_IDLE and the ARCH_KIRKWOOD options are set it is
pointless to define a new option CPU_IDLE_KIRKWOOD because it
is redundant.

The Makefile drivers directory contains a condition to compile
the cpuidle drivers:

obj-$(CONFIG_CPU_IDLE)          += cpuidle/

Hence, if CPU_IDLE is not set we won't enter this directory.

This patch removes the useless Kconfig option and replaces the
condition in the Makefile by CONFIG_ARCH_KIRKWOOD.

Signed-off-by: Daniel Lezcano 
Acked-by: Jason Cooper 
Signed-off-by: Rafael J. Wysocki

cpuidle : handle clockevent notify from the cpuidle framework

2013-03-31T23:10:27+00:00

When a cpu enters a deep idle state, the local timers are stopped and
the time framework falls back to the timer device used as a broadcast
timer.

The different cpuidle drivers are calling clockevents_notify ENTER/EXIT
when the idle state stops the local timer.

Add a new flag CPUIDLE_FLAG_TIMER_STOP which can be set by the cpuidle
drivers. If the flag is set, the cpuidle core code takes care of the
notification on behalf of the driver to avoid pointless code duplication.

Signed-off-by: Daniel Lezcano 
Reviewed-by: Thomas Gleixner 
Acked-by: Santosh Shilimkar 
Signed-off-by: Rafael J. Wysocki