blackbird-op-linux/Documentation/ABI/testing/sysfs-class-devfreq, branch master

PM / devfreq: Add clearing transitions stats

2019-12-30T00:59:05+00:00

Add clearing transition table and time in states devfreq statistics by writing 0 (zero) to trans_stat file in devfreq sysfs. An example use is like following: echo 0 > /sys/class/devfreq/devfreqX/trans_stat Signed-off-by: Kamil Konieczny [cw00.choi: Edit return value if entering the wrong value for reset and use arrary3_size() to get the size of 3-dimensional array] Signed-off-by: Chanwoo Choi

PM / devfreq: Add new name attribute for sysfs

2019-12-30T00:59:05+00:00

The commit 4585fbcb5331 ("PM / devfreq: Modify the device name as devfreq(X) for sysfs") changed the node name to devfreq(x). After this commit, it is not possible to get the device name through /sys/class/devfreq/devfreq(X)/*. Add new name attribute in order to get device name. Cc: stable@vger.kernel.org Fixes: 4585fbcb5331 ("PM / devfreq: Modify the device name as devfreq(X) for sysfs") Signed-off-by: Chanwoo Choi

ABI: fix some syntax issues at the ABI database

2019-06-14T16:17:11+00:00

On those three files, the ABI representation described at README are violated. - at sysfs-bus-iio-proximity-as3935: a ':' character is missing after "What" - at sysfs-class-devfreq: there's a typo at Description - at sysfs-class-cxl, it is using the ":" character at a file preamble, causing it to be misinterpreted as a tag. - On the other files, instead of "What", they use "Where". Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Mauro Carvalho Chehab Acked-by: Rafael J. Wysocki Acked-by: Andrew Donnellan # cxl Signed-off-by: Greg Kroah-Hartman

PM / devfreq: add comments and Documentation

2013-06-03T11:20:29+00:00

- Added missing ABI documents - Added comments to clarify the objectives of functions Signed-off-by: MyungJoo Ham Acked-by: Nishanth Menon Acked-by: Rajagopal Venkat

PM / devfreq: Add sysfs node to expose available governors

2012-11-20T09:46:24+00:00

Now that governor list can be variable, knowing the available governors is useful to be able to select a governor using relevant sysfs node. Cc: Rajagopal Venkat Cc: MyungJoo Ham Cc: Kyungmin Park Cc: "Rafael J. Wysocki" Cc: Kevin Hilman Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Nishanth Menon Signed-off-by: MyungJoo Ham

PM / devfreq: allow sysfs governor node to switch governor

2012-11-20T09:46:23+00:00

This allows us to select governor runtime from the default configuration without having to rebuild kernel or the devfreq driver using the sysfs node: /sys/class/devfreq/.../governor cat of the governor will return valid governor and an echo 'governor_name'>governor will switch governor Cc: Rajagopal Venkat Cc: MyungJoo Ham Cc: Kyungmin Park Cc: "Rafael J. Wysocki" Cc: Kevin Hilman Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Nishanth Menon Acked-by: MyungJoo Ham Signed-off-by: MyungJoo Ham

PM / devfreq: Add sysfs node for representing frequency transition information.

2012-11-20T07:05:44+00:00

This patch adds sysfs node which can be used to get information of frequency transition. It represents transition table which contains total number of transition of each freqeuncy state and time spent. It is inspired CPUFREQ's status driver. Signed-off-by: Jonghwa Lee [Added Documentation/ABI entry, updated kernel-doc, and resolved merge conflict] Signed-off-by: MyungJoo Ham

PM / devfreq: Add sysfs node to expose available frequencies

2012-11-20T06:59:32+00:00

devfreq governors such as ondemand are controlled by a min and max frequency, while governors like userspace governor allow us to set a specific frequency. However, for the same specific device, depending on the SoC, the available frequencies can vary. So expose the available frequencies as a snapshot over sysfs to allow informed decisions. This was inspired by cpufreq framework's equivalent for similar usage sysfs node: scaling_available_frequencies. Cc: Rajagopal Venkat Cc: MyungJoo Ham Cc: Kyungmin Park Cc: "Rafael J. Wysocki" Cc: Kevin Hilman Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Nishanth Menon Signed-off-by: MyungJoo Ham

PM / devfreq: Add current freq callback in device profile

2012-11-14T23:35:04+00:00

Devfreq returns governor predicted frequency as current frequency via sysfs interface. But device may not support all frequencies that governor predicts. So add a callback in device profile to get current freq from driver. Also add a new sysfs node to expose governor predicted next target frequency. Signed-off-by: Rajagopal Venkat Acked-by: MyungJoo Ham Signed-off-by: Rafael J. Wysocki

PM / devfreq: Core updates to support devices which can idle

2012-11-14T23:35:04+00:00

Prepare devfreq core framework to support devices which can idle. When device idleness is detected perhaps through runtime-pm, need some mechanism to suspend devfreq load monitoring and resume back when device is online. Present code continues monitoring unless device is removed from devfreq core. This patch introduces following design changes, - use per device work instead of global work to monitor device load. This enables suspend/resume of device devfreq and reduces monitoring code complexity. - decouple delayed work based load monitoring logic from core by introducing helpers functions to be used by governors. This provides flexibility for governors either to use delayed work based monitoring functions or to implement their own mechanism. - devfreq core interacts with governors via events to perform specific actions. These events include start/stop devfreq. This sets ground for adding suspend/resume events. The devfreq apis are not modified and are kept intact. Signed-off-by: Rajagopal Venkat Acked-by: MyungJoo Ham Signed-off-by: Rafael J. Wysocki