Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / ABI / testing / sysfs-class-devfreq

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+What:          /sys/class/devfreq/.../
+Date:          September 2011
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+               Provide a place in sysfs for the devfreq objects.
+               This allows accessing various devfreq specific variables.
+               The name of devfreq object denoted as ... is same as the
+               name of device using devfreq.
+
+What:          /sys/class/devfreq/.../governor
+Date:          September 2011
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+               The /sys/class/devfreq/.../governor show or set the name of the
+               governor used by the corresponding devfreq object.
+
+What:          /sys/class/devfreq/.../cur_freq
+Date:          September 2011
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+               The /sys/class/devfreq/.../cur_freq shows the current
+               frequency of the corresponding devfreq object. Same as
+               target_freq when get_cur_freq() is not implemented by
+               devfreq driver.
+
+What:          /sys/class/devfreq/.../target_freq
+Date:          September 2012
+Contact:       Rajagopal Venkat <rajagopal.venkat@linaro.org>
+Description:
+               The /sys/class/devfreq/.../target_freq shows the next governor
+               predicted target frequency of the corresponding devfreq object.
+
+What:          /sys/class/devfreq/.../polling_interval
+Date:          September 2011
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+               The /sys/class/devfreq/.../polling_interval shows and sets
+               the requested polling interval of the corresponding devfreq
+               object. The values are represented in ms. If the value is
+               less than 1 jiffy, it is considered to be 0, which means
+               no polling. This value is meaningless if the governor is
+               not polling; thus. If the governor is not using
+               devfreq-provided central polling
+               (/sys/class/devfreq/.../central_polling is 0), this value
+               may be useless.
+
+What:          /sys/class/devfreq/.../trans_stat
+Date:          October 2012
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Descrtiption:
+               This ABI shows the statistics of devfreq behavior on a
+               specific device. It shows the time spent in each state and
+               the number of transitions between states.
+               In order to activate this ABI, the devfreq target device
+               driver should provide the list of available frequencies
+               with its profile.
+
+What:          /sys/class/devfreq/.../userspace/set_freq
+Date:          September 2011
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+               The /sys/class/devfreq/.../userspace/set_freq shows and
+               sets the requested frequency for the devfreq object if
+               userspace governor is in effect.
+
+What:          /sys/class/devfreq/.../available_frequencies
+Date:          October 2012
+Contact:       Nishanth Menon <nm@ti.com>
+Description:
+               The /sys/class/devfreq/.../available_frequencies shows
+               the available frequencies of the corresponding devfreq object.
+               This is a snapshot of available frequencies and not limited
+               by the min/max frequency restrictions.
+
+What:          /sys/class/devfreq/.../available_governors
+Date:          October 2012
+Contact:       Nishanth Menon <nm@ti.com>
+Description:
+               The /sys/class/devfreq/.../available_governors shows
+               currently available governors in the system.
+
+What:          /sys/class/devfreq/.../min_freq
+Date:          January 2013
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+               The /sys/class/devfreq/.../min_freq shows and stores
+               the minimum frequency requested by users. It is 0 if
+               the user does not care. min_freq overrides the
+               frequency requested by governors.
+
+What:          /sys/class/devfreq/.../max_freq
+Date:          January 2013
+Contact:       MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+               The /sys/class/devfreq/.../max_freq shows and stores
+               the maximum frequency requested by users. It is 0 if
+               the user does not care. max_freq overrides the
+               frequency requested by governors and min_freq.
+               The max_freq overrides min_freq because max_freq may be
+               used to throttle devices to avoid overheating.