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* PM / devfreq: Define the constant governor nameChanwoo Choi2017-10-261-0/+7
| | | | | | | | | | | | | | | 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
* PM / devfreq: Show the all available frequenciesChanwoo Choi2017-10-261-2/+3
| | | | | | | | | | | | | | | | | | | The commit a76caf55e5b35 ("thermal: Add devfreq cooling") allows the devfreq device to use the cooling device. When the cooling down are required, the devfreq_cooling.c disables the OPP entry with the dev_pm_opp_disable(). In result, 'available_frequencies'[1] sysfs node never came to show the all available frequencies. [1] /sys/class/devfreq/.../available_frequencies So, this patch uses the 'freq_table' in the 'struct devfreq_dev_profile' in order to show the all available frequencies. - If 'freq_table' is NULL, devfreq core initializes them by using OPP values. - If 'freq_table' is initialized, devfreq core just uses the 'freq_table'. And this patch adds some comment about the sort way of 'freq_table'. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: Use the available min/max frequencyChanwoo Choi2017-10-261-0/+4
| | | | | | | | | | | | | | | | The commit a76caf55e5b35 ("thermal: Add devfreq cooling") is able to disable OPP as a cooling device. In result, both update_devfreq() and {min|max}_freq_show() have to consider the 'opp->available' status of each OPP. So, this patch adds the 'scaling_{min|max}_freq' to struct devfreq in order to indicate the available mininum and maximum frequency by adjusting OPP interface such as dev_pm_opp_{disable|enable}(). The 'scaling_{min|max}_freq' are used for on both update_devfreq() and {min|max}_freq_show(). Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: Move private devfreq_update_stats() into devfreqChanwoo Choi2017-08-281-13/+0
| | | | | | | | | | | THe devfreq_update_stats() updates the 'struct devfreq_dev_status' in order to get current status of devfreq device. It is only used for the governors. This patch moves the devfreq_update_stats() into devfreq directory. Signed-off-by: Chanwoo Choi <cwchoi00@gmail.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: Move struct devfreq_governor to devfreq directoryChanwoo Choi2017-04-121-29/+1
| | | | | | | | | This patch moves the struct devfreq_governor from header file to the devfreq directory because this structure is private data and it have to be only accessed by the devfreq core. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: Fix available_governor sysfsChanwoo Choi2017-01-311-0/+3
| | | | | | | | | | | | The devfreq using passive governor is not able to change the governor. So, the user can not change the governor through 'available_governor' sysfs entry. Also, the devfreq which don't use the passive governor is not able to change to 'passive' governor on the fly. Fixes: 996133119f57 ("PM / devfreq: Add new passive governor") Cc: stable@vger.kernel.org Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: Add new passive governorChanwoo Choi2016-05-031-0/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the new passive governor for DEVFREQ framework. The following governors are already present and used for DVFS (Dynamic Voltage and Frequency Scaling) drivers. The following governors are independently used for one device driver which don't give the influence to other device drviers and also don't receive the effect from other device drivers. - ondemand / performance / powersave / userspace The passive governor depends on operation of parent driver with specific governos extremely and is not able to decide the new frequency by oneself. According to the decided new frequency of parent driver with governor, the passive governor uses it to decide the appropriate frequency for own device driver. The passive governor must need the following information from device tree: - the source clock and OPP tables - the instance of parent device For exameple, there are one more devfreq device drivers which need to change their source clock according to their utilization on runtime. But, they share the same power line (e.g., regulator). So, specific device driver is operated as parent with ondemand governor and then the rest device driver with passive governor is influenced by parent device. Suggested-by: Myungjoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> [tjakobi: Reported RCU locking issue and cw00.choi fix it] Reported-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de> [linux.amoon: Reported possible recursive locking and cw00.choi fix it] Reported-by: Anand Moon <linux.amoon@gmail.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
* PM / devfreq: Add new DEVFREQ_TRANSITION_NOTIFIER notifierChanwoo Choi2016-05-031-1/+58
| | | | | | | | | | | | | | | | | | This patch adds the new DEVFREQ_TRANSITION_NOTIFIER notifier to send the notification when the frequency of device is changed. This notifier has two state as following: - DEVFREQ_PRECHANGE : Notify it before chaning the frequency of device - DEVFREQ_POSTCHANGE : Notify it after changed the frequency of device And this patch adds the resourced-managed function to release the resource automatically when error happen. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> [m.reichl and linux.amoon: Tested it on exynos4412-odroidu3 board] Tested-by: Markus Reichl <m.reichl@fivetechno.de> Tested-by: Anand Moon <linux.amoon@gmail.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
* PM / devfreq: Add devfreq_get_devfreq_by_phandle()Chanwoo Choi2016-05-031-0/+9
| | | | | | | | | | | | This patch adds the new devfreq_get_devfreq_by_phandle() OF helper function which can find the instance of devfreq device by using phandle ("devfreq"). Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> [m.reichl and linux.amoon: Tested it on exynos4412-odroidu3 board] Tested-by: Markus Reichl <m.reichl@fivetechno.de> Tested-by: Anand Moon <linux.amoon@gmail.com> Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
* PM / devfreq: Set the freq_table of devfreq deviceChanwoo Choi2016-01-131-1/+1
| | | | | | | | | | | | | | | | | This patch initialize the freq_table array of each devfreq device by using the devfreq_set_freq_table(). If freq_table is NULL, the devfreq framework is not able to support the frequency transtion information through sysfs. The OPP core uses the integer type for the number of opps in the opp list and uses the 'unsigned long' type for each frequency. So, this patch modifies the type of some variable as following: - the type of freq_table : unsigned int -> unsigned long - the type of max_state : unsigned int -> int - Corrected types, format strings, mutex usages by MyungJoo Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: comments for get_dev_status usage updatedMyungJoo Ham2015-09-111-1/+8
| | | | | | | With the introduction of devfreq_update_stats(), governors are not recommended to use get_dev_status() directly. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: cache the last call to get_dev_status()Javi Merino2015-09-111-0/+15
| | | | | | | | | | The return value of get_dev_status() can be reused. Cache it so that other parts of the kernel can reuse it instead of having to call the same function again. Cc: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Javi Merino <javi.merino@arm.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM: Eliminate CONFIG_PM_RUNTIMERafael J. Wysocki2014-12-191-1/+1
| | | | | | | | | | Having switched over all of the users of CONFIG_PM_RUNTIME to use CONFIG_PM directly, turn the latter into a user-selectable option and drop the former entirely from the tree. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Kevin Hilman <khilman@linaro.org>
* PM / devfreq: Add devm_devfreq_{register,unregister}_opp_notfier functionChanwoo Choi2014-05-241-0/+14
| | | | | | | | | | | This patch add resource-managed function for devfreq opp as following functions. The devm_devfreq_register_opp_notifier() manages automatically the registration of devfreq opp using device resource management. - devm_devfreq_register_opp_notifier - devm_devfreq_unregister_opp_notifier() Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: Add resource-managed function for devfreq deviceChanwoo Choi2014-05-241-1/+20
| | | | | | | | | | | This patch add resource-managed function for devfreq device as following functions. The devm_devfreq_add_device() manages automatically the memory of devfreq device using device resource management. - devm_devfreq_add_device() - devm_devfreq_remove_device() Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-11-151-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "Usual earth-shaking, news-breaking, rocket science pile from trivial.git" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits) doc: usb: Fix typo in Documentation/usb/gadget_configs.txt doc: add missing files to timers/00-INDEX timekeeping: Fix some trivial typos in comments mm: Fix some trivial typos in comments irq: Fix some trivial typos in comments NUMA: fix typos in Kconfig help text mm: update 00-INDEX doc: Documentation/DMA-attributes.txt fix typo DRM: comment: `halve' -> `half' Docs: Kconfig: `devlopers' -> `developers' doc: typo on word accounting in kprobes.c in mutliple architectures treewide: fix "usefull" typo treewide: fix "distingush" typo mm/Kconfig: Grammar s/an/a/ kexec: Typo s/the/then/ Documentation/kvm: Update cpuid documentation for steal time and pv eoi treewide: Fix common typo in "identify" __page_to_pfn: Fix typo in comment Correct some typos for word frequency clk: fixed-factor: Fix a trivial typo ...
| * Correct some typos for word frequencyLABBE Corentin2013-10-141-1/+1
| | | | | | | | | | Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | PM / OPP: rename header to linux/pm_opp.hNishanth Menon2013-10-251-1/+1
| | | | | | | | | | | | | | | | | | | | Since Operating Performance Points (OPP) functions are specific to device specific power management, be specific and rename opp.h to pm_opp.h Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | PM / OPP: rename data structures to dev_pm equivalentsNishanth Menon2013-10-251-2/+2
|/ | | | | | | | | | | | | | | | Since Operating Performance Points (OPP) data structures are specific to device specific power management, be specific and rename opp_* data structures in OPP library with dev_pm_opp_* equivalent. Affected structures are: struct opp enum opp_event Minor checkpatch warning resulting of this change was fixed as well. Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* PM / devfreq: add comments and DocumentationMyungJoo Ham2013-06-031-0/+2
| | | | | | | | | - Added missing ABI documents - Added comments to clarify the objectives of functions Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Acked-by: Nishanth Menon <nm@ti.com> Acked-by: Rajagopal Venkat <rajagopal.venkat@linaro.org>
* PM / devfreq: Fix compiler warnings for CONFIG_PM_DEVFREQ unsetRajagopal Venkat2013-04-021-8/+8
| | | | | | | | | Fix compiler warnings generated when devfreq is not enabled (CONFIG_PM_DEVFREQ is not set). 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>
* PM / devfreq: remove compiler error when a governor is moduleMyungJoo Ham2012-11-261-1/+1
| | | | | | | | With the intruction of patch, eff607fdb1f787da1fedf46ab6e64adc2afd1c5a, it became possible to include a governor as a module. Thus the #ifdef statement for a governor should become #if IS_ENABLED. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: map devfreq drivers to governor using nameNishanth Menon2012-11-201-17/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* PM / devfreq: provide hooks for governors to be registeredNishanth Menon2012-11-201-0/+3
| | | | | | | | | | | | | | | | | | | Add devfreq_add_governor and devfreq_remove_governor which can be invoked by governors to register with devfreq. This sets up the stage to dynamically switch governors and allow governors to be dynamically loaded as well. 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>
* PM / devfreq: Add sysfs node for representing frequency transition information.Jonghwa Lee2012-11-201-0/+15
| | | | | | | | | | 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 <jonghwa3.lee@samsung.com> [Added Documentation/ABI entry, updated kernel-doc, and resolved merge conflict] Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: documentation cleanups for devfreq headerNishanth Menon2012-11-201-27/+27
| | | | | | | | | | | | | | | | | | | | | struct parameters need to have ':' in documentation for scripts/kernel-doc to parse appropriately. Fix the errors reported by: ./scripts/kernel-doc include/linux/devfreq.h >/dev/null 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: Randy Dunlap <rdunlap@xenotime.net> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
* PM / devfreq: Add current freq callback in device profileRajagopal Venkat2012-11-151-0/+3
| | | | | | | | | | | | 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 <rajagopal.venkat@linaro.org> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* PM / devfreq: Add suspend and resume apisRajagopal Venkat2012-11-151-0/+12
| | | | | | | | | | Add devfreq suspend/resume apis for devfreq users. This patch supports suspend and resume of devfreq load monitoring, required for devices which can idle. 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>
* PM / devfreq: Core updates to support devices which can idleRajagopal Venkat2012-11-151-24/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* PM / devfreq: add relation of recommended frequency.MyungJoo Ham2012-03-171-3/+13
| | | | | | | | | | | | | | | | | | | The semantics of "target frequency" given to devfreq driver from devfreq framework has always been interpretted as "at least" or GLB (greatest lower bound). However, the framework might want the device driver to limit its max frequency (LUB: least upper bound), especially if it is given by thermal framework (it's too hot). Thus, the target fuction should have another parameter to express whether the framework wants GLB or LUB. And, the additional parameter, "u32 flags", does it. With the update, devfreq_recommended_opp() is also updated. 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> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM / devfreq: add min/max_freq limit requested by users.MyungJoo Ham2012-01-201-0/+5
| | | | | | | | 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>
* PM / devfreq: fixed syntax errors.MyungJoo Ham2012-01-201-2/+2
| | | | | | | | | If devfreq.h was included without CONFIG_PM_DEVFREQ, there has been a compiler error with an additional semicolon added. This patch removes that errorneous semicolon. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
* PM / devfreq: fix private_dataJonathan Corbet2011-11-071-1/+1
| | | | | | | | | The "private_date" field in struct devfreq_dev_status almost certainly wants to be "private_data"; since there are no in-tree users of this functionality, now seems like an easy time to make the fix. Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM / devfreq: Add basic governorsMyungJoo Ham2011-10-021-0/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* PM: Introduce devfreq: generic DVFS framework with device-specific OPPsMyungJoo Ham2011-10-021-0/+203
With OPPs, a device may have multiple operable frequency and voltage sets. However, there can be multiple possible operable sets and a system will need to choose one from them. In order to reduce the power consumption (by reducing frequency and voltage) without affecting the performance too much, a Dynamic Voltage and Frequency Scaling (DVFS) scheme may be used. This patch introduces the DVFS capability to non-CPU devices with OPPs. DVFS is a techique whereby the frequency and supplied voltage of a device is adjusted on-the-fly. DVFS usually sets the frequency as low as possible with given conditions (such as QoS assurance) and adjusts voltage according to the chosen frequency in order to reduce power consumption and heat dissipation. The generic DVFS for devices, devfreq, may appear quite similar with /drivers/cpufreq. However, cpufreq does not allow to have multiple devices registered and is not suitable to have multiple heterogenous devices with different (but simple) governors. Normally, DVFS mechanism controls frequency based on the demand for the device, and then, chooses voltage based on the chosen frequency. devfreq also controls the frequency based on the governor's frequency recommendation and let OPP pick up the pair of frequency and voltage based on the recommended frequency. Then, the chosen OPP is passed to device driver's "target" callback. When PM QoS is going to be used with the devfreq device, the device driver should enable OPPs that are appropriate with the current PM QoS requests. In order to do so, the device driver may call opp_enable and opp_disable at the notifier callback of PM QoS so that PM QoS's update_target() call enables the appropriate OPPs. Note that at least one of OPPs should be enabled at any time; be careful when there is a transition. 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>
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