Re: [PATCH] PM / devfreq: correct Kconfig dependency

From: Rafael J. Wysocki
Date: Mon Nov 14 2011 - 18:14:12 EST


On Monday, November 14, 2011, MyungJoo Ham wrote:
> Devfreq does not depend on OPP. The dependency is removed.
>
> Signed-off-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>

Applied to linux-pm/pm-fixes.

Thanks,
Rafael


> ---
> drivers/devfreq/Kconfig | 41 +++++++++++++++++------------------------
> 1 files changed, 17 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
> index 8fd34e7..87a742f 100644
> --- a/drivers/devfreq/Kconfig
> +++ b/drivers/devfreq/Kconfig
> @@ -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
> bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support"
> - depends on PM_OPP && ARCH_HAS_DEVFREQ
> help
> - With OPP support, a device may have a list of frequencies and
> - voltages available. DEVFREQ, a generic DVFS framework can be
> - registered for a device with OPP support in order to let the
> - governor provided to DEVFREQ choose an operating frequency
> - based on the OPP's list and the policy given with DEVFREQ.
> + A device may have a list of frequencies and voltages available.
> + devfreq, a generic DVFS framework can be registered for a device
> + in order to let the governor provided to devfreq choose an
> + operating frequency based on the device driver's policy.
>
> - 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
> - OPP list changes (each frequency/voltage pair in OPP may be
> - disabled or enabled).
> + notification to "nb", a notifier block, of devfreq.
>
> - 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
> - 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"
> - clock frequency from the OPP of the device, which is also attached
> - to a device by 1-to-1. The device registering DEVFREQ takes the
> - responsiblity to "interpret" the frequency listed in OPP and
> + clock frequency of the device, which is also attached
> + to a device by 1-to-1. The device registering devfreq takes the
> + responsiblity to "interpret" the representative frequency and
> 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
>
>

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