summaryrefslogtreecommitdiff
path: root/drivers/devfreq/governor_userspace.c
AgeCommit message (Collapse)AuthorFilesLines
2022-11-20PM/devfreq: governor: Add a private governor_data for governorKant Fan1-6/+6
The member void *data in the structure devfreq can be overwrite by governor_userspace. For example: 1. The device driver assigned the devfreq governor to simple_ondemand by the function devfreq_add_device() and init the devfreq member void *data to a pointer of a static structure devfreq_simple_ondemand_data by the function devfreq_add_device(). 2. The user changed the devfreq governor to userspace by the command "echo userspace > /sys/class/devfreq/.../governor". 3. The governor userspace alloced a dynamic memory for the struct userspace_data and assigend the member void *data of devfreq to this memory by the function userspace_init(). 4. The user changed the devfreq governor back to simple_ondemand by the command "echo simple_ondemand > /sys/class/devfreq/.../governor". 5. The governor userspace exited and assigned the member void *data in the structure devfreq to NULL by the function userspace_exit(). 6. The governor simple_ondemand fetched the static information of devfreq_simple_ondemand_data in the function devfreq_simple_ondemand_func() but the member void *data of devfreq was assigned to NULL by the function userspace_exit(). 7. The information of upthreshold and downdifferential is lost and the governor simple_ondemand can't work correctly. The member void *data in the structure devfreq is designed for a static pointer used in a governor and inited by the function devfreq_add_device(). This patch add an element named governor_data in the devfreq structure which can be used by a governor(E.g userspace) who want to assign a private data to do some private things. Fixes: ce26c5bb9569 ("PM / devfreq: Add basic governors") Cc: stable@vger.kernel.org # 5.10+ Reviewed-by: Chanwoo Choi <cwchoi00@gmail.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kant Fan <kant@allwinnertech.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2021-06-17PM / devfreq: userspace: Use DEVICE_ATTR_RW macroYueHaibing1-5/+5
Use DEVICE_ATTR_RW helper instead of plain DEVICE_ATTR, which makes the code a bit shorter and easier to read. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2020-03-25PM / devfreq: Use constant name of userspace governorpierre Kuo1-1/+1
Based on commit aa7c352f9841 ("PM / devfreq: Define the constant governor name"), use constant name for userspace governor. Signed-off-by: pierre Kuo <vichy.kuo@gmail.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02PM / devfreq: Don't adjust to user limits in governorsMatthias Kaehlcke1-12/+4
Several governors use the user space limits df->min/max_freq to adjust the target frequency. This is not necessary, since update_devfreq() already takes care of this. Instead the governor can request the available min/max frequency by setting the target frequency to DEVFREQ_MIN/MAX_FREQ and let update_devfreq() take care of any adjustments. Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Brian Norris <briannorris@chromium.org> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2017-10-26PM / devfreq: Define the constant governor nameChanwoo Choi1-1/+1
Prior to that, the devfreq device uses the governor name when adding the itself. In order to prevent the mistake used the wrong governor name, this patch defines the governor name as a constant and then uses them instead of using the string directly. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Kukjin Kim <kgene@kernel.org> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: linux-samsung-soc@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org
2017-07-06PM / devfreq: constify attribute_group structures.Arvind Yadav1-1/+1
attribute_groups are not supposed to change at runtime. All functions working with attribute_groups provided by <linux/sysfs.h> work with const attribute_group. So mark the non-const structs as const. File size before: text data bss dec hex filename 621 176 0 797 31d drivers/devfreq/governor_userspace.o File size After adding 'const': text data bss dec hex filename 670 144 0 814 32e drivers/devfreq/governor_userspace.o Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2017-01-31PM / devfreq: Fix the wrong description for userspace governorChanwoo Choi1-2/+1
This patch fixes the wrong description of governor_userspace.c and removes the unneeded blank line. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2017-01-31PM / devfreq: Don't delete sysfs group twiceChris Diamand1-1/+7
The 'userspace' governor adds a sysfs entry, which is removed when the governor is changed, or the devfreq device is released. However, when the latter occurs via device_unregister(), device_del() is called first, which removes the sysfs entries recursively and deletes the kobject. This means we get an Oops when the governor calls sysfs_remove_group() on the deleted kobject. Fix this by only doing the call when kobj *hasn't* been kobject_del()'d. Note that we can't just remove the call to sysfs_remove_group() entirely - it's needed for when the governor is changed to one which doesn't need a sysfs entry. Signed-off-by: Chris Diamand <chris.diamand@arm.com> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-20PM / devfreq: governors: add GPL module license and allow module buildNishanth Menon1-0/+2
Add GPL module license and remove the static build restrictions for building governors. This allows governors now to be loaded on a need basis and reloaded independently of kernel build Cc: Rajagopal Venkat <rajagopal.venkat@linaro.org> Cc: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Kevin Hilman <khilman@ti.com> Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-20PM / devfreq: map devfreq drivers to governor using nameNishanth Menon1-1/+1
Allow devfreq drivers to register a preferred governor name and when the devfreq governor loads itself at a later point required drivers are managed appropriately, at the time of unload of a devfreq governor, stop managing those drivers as well. Since the governor structures do not need to be exposed anymore, remove the definitions and make them static NOTE: devfreq_list_lock is now used to protect governor start and stop - as this allows us to protect governors and devfreq with the proper dependencies as needed. As part of this change, change the registration of exynos bus driver to request for ondemand using the governor name. Cc: Rajagopal Venkat <rajagopal.venkat@linaro.org> Cc: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Kevin Hilman <khilman@ti.com> Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Nishanth Menon <nm@ti.com> [Merge conflict resolved by MyungJoo Ham] Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-20PM / devfreq: register governors with devfreq frameworkNishanth Menon1-0/+18
With the new registration functions, governors can be now registered with devfreq framework. NOTE: generates 'discards qualifiers from pointer target type' build warnings, which the next patche in this series fixes Cc: Rajagopal Venkat <rajagopal.venkat@linaro.org> Cc: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Kevin Hilman <khilman@ti.com> Cc: linux-pm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-15PM / devfreq: Core updates to support devices which can idleRajagopal Venkat1-3/+20
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 <rajagopal.venkat@linaro.org> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-01-20PM / devfreq: add min/max_freq limit requested by users.MyungJoo Ham1-3/+12
The frequency requested to devfreq device driver from devfreq governors is restricted by min_freq and max_freq input. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
2011-10-02PM / devfreq: Add basic governorsMyungJoo Ham1-0/+116
Four cpufreq-like governors are provided as examples. powersave: use the lowest frequency possible. The user (device) should set the polling_ms as 0 because polling is useless for this governor. performance: use the highest freqeuncy possible. The user (device) should set the polling_ms as 0 because polling is useless for this governor. userspace: use the user specified frequency stored at devfreq.user_set_freq. With sysfs support in the following patch, a user may set the value with the sysfs interface. simple_ondemand: simplified version of cpufreq's ondemand governor. When a user updates OPP entries (enable/disable/add), OPP framework automatically notifies devfreq to update operating frequency accordingly. Thus, devfreq users (device drivers) do not need to update devfreq manually with OPP entry updates or set polling_ms for powersave , performance, userspace, or any other "static" governors. Note that these are given only as basic examples for governors and any devices with devfreq may implement their own governors with the drivers and use them. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Reviewed-by: Mike Turquette <mturquette@ti.com> Acked-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>