sysfs-class-devfreq (4689B)
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 55What: /sys/class/devfreq/.../available_frequencies 56Date: October 2012 57Contact: Nishanth Menon <nm@ti.com> 58Description: 59 The /sys/class/devfreq/.../available_frequencies shows 60 the available frequencies of the corresponding devfreq object. 61 This is a snapshot of available frequencies and not limited 62 by the min/max frequency restrictions. 63 64What: /sys/class/devfreq/.../available_governors 65Date: October 2012 66Contact: Nishanth Menon <nm@ti.com> 67Description: 68 The /sys/class/devfreq/.../available_governors shows 69 currently available governors in the system. 70 71What: /sys/class/devfreq/.../min_freq 72Date: January 2013 73Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 74Description: 75 The /sys/class/devfreq/.../min_freq shows and stores 76 the minimum frequency requested by users. It is 0 if 77 the user does not care. min_freq overrides the 78 frequency requested by governors. 79 80What: /sys/class/devfreq/.../max_freq 81Date: January 2013 82Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 83Description: 84 The /sys/class/devfreq/.../max_freq shows and stores 85 the maximum frequency requested by users. It is 0 if 86 the user does not care. max_freq overrides the 87 frequency requested by governors and min_freq. 88 The max_freq overrides min_freq because max_freq may be 89 used to throttle devices to avoid overheating. 90 91What: /sys/class/devfreq/.../polling_interval 92Date: September 2011 93Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 94Description: 95 The /sys/class/devfreq/.../polling_interval shows and sets 96 the requested polling interval of the corresponding devfreq 97 object. The values are represented in ms. If the value is 98 less than 1 jiffy, it is considered to be 0, which means 99 no polling. This value is meaningless if the governor is 100 not polling. 101 102 A list of governors that support the node: 103 - simple_ondmenad 104 - tegra_actmon 105 106What: /sys/class/devfreq/.../userspace/set_freq 107Date: September 2011 108Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 109Description: 110 The /sys/class/devfreq/.../userspace/set_freq shows and 111 sets the requested frequency for the devfreq object if 112 userspace governor is in effect. 113 114 A list of governors that support the node: 115 - userspace 116 117What: /sys/class/devfreq/.../timer 118Date: July 2020 119Contact: Chanwoo Choi <cw00.choi@samsung.com> 120Description: 121 This ABI shows and stores the kind of work timer by users. 122 This work timer is used by devfreq workqueue in order to 123 monitor the device status such as utilization. The user 124 can change the work timer on runtime according to their demand 125 as following:: 126 127 echo deferrable > /sys/class/devfreq/.../timer 128 echo delayed > /sys/class/devfreq/.../timer 129 130 A list of governors that support the node: 131 - simple_ondemand