1What:		/sys/class/devfreq/.../
  2Date:		September 2011
  3Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
  4Description:
  5		Provide a place in sysfs for the devfreq objects.
  6		This allows accessing various devfreq specific variables.
  7		The name of devfreq object denoted as ... is same as the
  8		name of device using devfreq.
  9
 10What:		/sys/class/devfreq/.../name
 11Date:		November 2019
 12Contact:	Chanwoo Choi <cw00.choi@samsung.com>
 13Description:
 14		The /sys/class/devfreq/.../name shows the name of device
 15		of the corresponding devfreq object.
 16
 17What:		/sys/class/devfreq/.../governor
 18Date:		September 2011
 19Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 20Description:
 21		The /sys/class/devfreq/.../governor show or set the name of the
 22		governor used by the corresponding devfreq object.
 23
 24What:		/sys/class/devfreq/.../cur_freq
 25Date:		September 2011
 26Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 27Description:
 28		The /sys/class/devfreq/.../cur_freq shows the current
 29		frequency of the corresponding devfreq object. Same as
 30		target_freq when get_cur_freq() is not implemented by
 31		devfreq driver.
 32
 33What:		/sys/class/devfreq/.../target_freq
 34Date:		September 2012
 35Contact:	Rajagopal Venkat <rajagopal.venkat@linaro.org>
 36Description:
 37		The /sys/class/devfreq/.../target_freq shows the next governor
 38		predicted target frequency of the corresponding devfreq object.
 39
 40What:		/sys/class/devfreq/.../trans_stat
 41Date:		October 2012
 42Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 43Description:
 44		This ABI shows or clears the statistics of devfreq behavior
 45		on a specific device. It shows the time spent in each state
 46		and the number of transitions between states.
 47		In order to activate this ABI, the devfreq target device
 48		driver should provide the list of available frequencies
 49		with its profile. If need to reset the statistics of devfreq
 50		behavior on a specific device, enter 0(zero) to 'trans_stat'
 51		as following::
 52
 53			echo 0 > /sys/class/devfreq/.../trans_stat
 54
 55		If the transition table is bigger than PAGE_SIZE, reading
 56		this will return an -EFBIG error.
 57
 58What:		/sys/class/devfreq/.../available_frequencies
 59Date:		October 2012
 60Contact:	Nishanth Menon <nm@ti.com>
 61Description:
 62		The /sys/class/devfreq/.../available_frequencies shows
 63		the available frequencies of the corresponding devfreq object.
 64		This is a snapshot of available frequencies and not limited
 65		by the min/max frequency restrictions.
 66
 67What:		/sys/class/devfreq/.../available_governors
 68Date:		October 2012
 69Contact:	Nishanth Menon <nm@ti.com>
 70Description:
 71		The /sys/class/devfreq/.../available_governors shows
 72		currently available governors in the system.
 73
 74What:		/sys/class/devfreq/.../min_freq
 75Date:		January 2013
 76Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 77Description:
 78		The /sys/class/devfreq/.../min_freq shows and stores
 79		the minimum frequency requested by users. It is 0 if
 80		the user does not care. min_freq overrides the
 81		frequency requested by governors.
 82
 83What:		/sys/class/devfreq/.../max_freq
 84Date:		January 2013
 85Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 86Description:
 87		The /sys/class/devfreq/.../max_freq shows and stores
 88		the maximum frequency requested by users. It is 0 if
 89		the user does not care. max_freq overrides the
 90		frequency requested by governors and min_freq.
 91		The max_freq overrides min_freq because max_freq may be
 92		used to throttle devices to avoid overheating.
 93
 94What:		/sys/class/devfreq/.../polling_interval
 95Date:		September 2011
 96Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
 97Description:
 98		The /sys/class/devfreq/.../polling_interval shows and sets
 99		the requested polling interval of the corresponding devfreq
100		object. The values are represented in ms. If the value is
101		less than 1 jiffy, it is considered to be 0, which means
102		no polling. This value is meaningless if the governor is
103		not polling.
104
105		A list of governors that support the node:
106		- simple_ondmenad
107		- tegra_actmon
108
109What:		/sys/class/devfreq/.../userspace/set_freq
110Date:		September 2011
111Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
112Description:
113		The /sys/class/devfreq/.../userspace/set_freq shows and
114		sets the requested frequency for the devfreq object if
115		userspace governor is in effect.
116
117		A list of governors that support the node:
118		- userspace
119
120What:		/sys/class/devfreq/.../timer
121Date:		July 2020
122Contact:	Chanwoo Choi <cw00.choi@samsung.com>
123Description:
124		This ABI shows and stores the kind of work timer by users.
125		This work timer is used by devfreq workqueue in order to
126		monitor the device status such as utilization. The user
127		can change the work timer on runtime according to their demand
128		as following::
129
130			echo deferrable > /sys/class/devfreq/.../timer
131			echo delayed > /sys/class/devfreq/.../timer
132
133		A list of governors that support the node:
134		- simple_ondemand