| 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/.../name |
| Date: November 2019 |
| Contact: Chanwoo Choi <cw00.choi@samsung.com> |
| Description: |
| The /sys/class/devfreq/.../name shows the name of device |
| of the corresponding devfreq object. |
| |
| 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/.../trans_stat |
| Date: October 2012 |
| Contact: MyungJoo Ham <myungjoo.ham@samsung.com> |
| Description: |
| This ABI shows or clears 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. If need to reset the statistics of devfreq |
| behavior on a specific device, enter 0(zero) to 'trans_stat' |
| as following:: |
| |
| echo 0 > /sys/class/devfreq/.../trans_stat |
| |
| If the transition table is bigger than PAGE_SIZE, reading |
| this will return an -EFBIG error. |
| |
| 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. |
| |
| 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. |
| |
| A list of governors that support the node: |
| - simple_ondmenad |
| - tegra_actmon |
| |
| 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. |
| |
| A list of governors that support the node: |
| - userspace |
| |
| What: /sys/class/devfreq/.../timer |
| Date: July 2020 |
| Contact: Chanwoo Choi <cw00.choi@samsung.com> |
| Description: |
| This ABI shows and stores the kind of work timer by users. |
| This work timer is used by devfreq workqueue in order to |
| monitor the device status such as utilization. The user |
| can change the work timer on runtime according to their demand |
| as following:: |
| |
| echo deferrable > /sys/class/devfreq/.../timer |
| echo delayed > /sys/class/devfreq/.../timer |
| |
| A list of governors that support the node: |
| - simple_ondemand |
