cpufreq / core: Fix typo in comment describing show_bios_limit()

show_bios_limit is mistakenly written as show_scaling_driver in a comment
describing purpose of show_bios_limit() routine.

Fix it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq / core: Fix printing of governor and driver name

Arrays for governer and driver name are of size CPUFREQ_NAME_LEN or 16.
i.e. 15 bytes for name and 1 for trailing '\0'.

When cpufreq driver print these names (for sysfs), it includes '\n' or ' ' in
the fmt string and still passes length as CPUFREQ_NAME_LEN. If the driver or
governor names are using all 15 fields allocated to them, then the trailing '\n'
or ' ' will never be printed. And so commands like:

root@linaro-developer# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver

will print something like:

cpufreq_foodrvroot@linaro-developer#

Fix this by increasing print length by one character.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: return early from __cpufreq_driver_getavg()

There is no need to do cpufreq_get_cpu() and cpufreq_put_cpu() for drivers that
don't support getavg() routine.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Fix sparse warning by making local function static

cpufreq_disabled() is a local function, so should be marked static.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Avoid calling cpufreq driver's target() routine if target_freq == policy->cur

Avoid calling cpufreq driver's target() routine if new frequency is same as
policies current frequency.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Make sure target freq is within limits

__cpufreq_driver_target() must not pass target frequency beyond the
limits of current policy.

Today most of cpufreq platform drivers are doing this check in their
target routines. Why not move it to __cpufreq_driver_target()?

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Remove unnecessary initialization of a local variable

Remove an unnecessary initializer for the 'ret' variable in
__cpufreq_set_policy().

[rjw: Modified the subject and changelog slightly.]
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Manage only online cpus

cpufreq core doesn't manage offline cpus and if driver->init() has returned
mask including offline cpus, it may result in unwanted behavior by cpufreq core
or governors.

We need to get only online cpus in this mask. There are two places to fix this
mask, cpufreq core and cpufreq driver. It makes sense to do this at common place
and hence is done in core.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Notify governors when cpus are hot-[un]plugged

Because cpufreq core and governors worry only about the online cpus, if a cpu is
hot [un]plugged, we must notify governors about it, otherwise be ready to expect
something unexpected.

We already have notifiers in the form of CPUFREQ_GOV_START/CPUFREQ_GOV_STOP, we
just need to call them now.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
cpufreq: Don't use cpu removed during cpufreq_driver_unregister

This is how the core works:
cpufreq_driver_unregister()
 - subsys_interface_unregister()
   - for_each_cpu() call cpufreq_remove_dev(), i.e. 0,1,2,3,4 when we
     unregister.

cpufreq_remove_dev():
 - Remove policy node
 - Call cpufreq_add_dev() for next cpu, sharing mask with removed cpu.
   i.e. When cpu 0 is removed, we call it for cpu 1. And when called for cpu 2,
   we call it for cpu 3.
   - cpufreq_add_dev() would call cpufreq_driver->init()
   - init would return mask as AND of 2, 3 and 4 for cluster A7.
   - cpufreq core would do online_cpu && policy->cpus
     Here is the BUG(). Because cpu hasn't died but we have just unregistered
     the cpufreq driver, online cpu would still have cpu 2 in it. And so thing
     go bad again.

Solution: Keep cpumask of cpus that are registered with cpufreq core and clear
	  cpus when we get a call from subsys_interface_unregister() via
	  cpufreq_remove_dev().

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Conflicts:
	drivers/cpufreq/cpufreq.c