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PM / devfreq: correct Kconfig dependency

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Devfreq does not depend on OPP. The dependency is removed.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This commit is contained in:
MyungJoo Ham 2011-11-14 23:31:35 +01:00 committed by Rafael J. Wysocki
parent 9f3bdd4f93
commit 6c81f90588
1 changed files with 17 additions and 24 deletions
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41
drivers/devfreq/Kconfig
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@ -1,36 +1,29 @@
config ARCH_HAS_DEVFREQ
bool
depends on ARCH_HAS_OPP
help
Denotes that the architecture supports DEVFREQ. If the architecture
supports multiple OPP entries per device and the frequency of the
devices with OPPs may be altered dynamically, the architecture
supports DEVFREQ.
menuconfig PM_DEVFREQ menuconfig PM_DEVFREQ
bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support" bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support"
depends on PM_OPP && ARCH_HAS_DEVFREQ
help help
With OPP support, a device may have a list of frequencies and A device may have a list of frequencies and voltages available.
voltages available. DEVFREQ, a generic DVFS framework can be devfreq, a generic DVFS framework can be registered for a device
registered for a device with OPP support in order to let the in order to let the governor provided to devfreq choose an
governor provided to DEVFREQ choose an operating frequency operating frequency based on the device driver's policy.
based on the OPP's list and the policy given with DEVFREQ.
Each device may have its own governor and policy. DEVFREQ can Each device may have its own governor and policy. Devfreq can
reevaluate the device state periodically and/or based on the reevaluate the device state periodically and/or based on the
OPP list changes (each frequency/voltage pair in OPP may be notification to "nb", a notifier block, of devfreq.
disabled or enabled).
Like some CPUs with CPUFREQ, a device may have multiple clocks. Like some CPUs with CPUfreq, a device may have multiple clocks.
However, because the clock frequencies of a single device are However, because the clock frequencies of a single device are
determined by the single device's state, an instance of DEVFREQ determined by the single device's state, an instance of devfreq
is attached to a single device and returns a "representative" is attached to a single device and returns a "representative"
clock frequency from the OPP of the device, which is also attached clock frequency of the device, which is also attached
to a device by 1-to-1. The device registering DEVFREQ takes the to a device by 1-to-1. The device registering devfreq takes the
responsiblity to "interpret" the frequency listed in OPP and responsiblity to "interpret" the representative frequency and
to set its every clock accordingly with the "target" callback to set its every clock accordingly with the "target" callback
given to DEVFREQ. given to devfreq.
When OPP is used with the devfreq device, it is recommended to
register devfreq's nb to the OPP's notifier head. If OPP is
used with the devfreq device, you may use OPP helper
functions defined in devfreq.h.
if PM_DEVFREQ if PM_DEVFREQ