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