summaryrefslogtreecommitdiff
path: root/drivers/devfreq
AgeCommit message (Collapse)AuthorFilesLines
2012-11-28PM / devfreq: remove compiler error with module governors (2)MyungJoo Ham1-0/+5
Governors compiled as modules may use these functions. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-26PM / devfreq: Fix return value in devfreq_remove_governor()Sachin Kamat1-1/+1
Use the value obtained from the function instead of -EINVAL. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-26PM / devfreq: Fix incorrect argument in error messageSachin Kamat1-1/+1
'g' is cast to the error return code. Hence gives the following error which is fixed by this patch. drivers/devfreq/devfreq.c:645 devfreq_remove_governor() error: 'g' dereferencing possible ERR_PTR() Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-26PM / devfreq: missing rcu_read_lock() added for find_device_opp()MyungJoo Ham1-6/+20
opp_get_notifier() uses find_device_opp(), which requires to held rcu_read_lock. In order to keep the notifier-header valid, we have added rcu_read_lock(). Reported-by: Kees Cook <keescook@chromium.org> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-20PM / devfreq: exynos4_bus.c: Fixed an alignment of the func call args.Sangho Yi1-1/+1
I fixed the following check item (via checkpatch.pl --strict option): CHECK: Alignment should match open parenthesis Signed-off-by: Sangho Yi <antiroot@gmail.com> [Merge conflict resolved] Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-20PM / devfreq: Add sysfs node to expose available governorsNishanth Menon1-0/+22
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 <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> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-20PM / devfreq: allow sysfs governor node to switch governorNishanth Menon1-1/+44
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 <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: governors: add GPL module license and allow module buildNishanth Menon5-4/+12
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 Menon6-13/+92
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 Menon4-0/+72
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>
2012-11-20PM / devfreq: provide hooks for governors to be registeredNishanth Menon2-0/+95
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>
2012-11-20PM / devfreq: export update_devfreqNishanth Menon1-0/+1
Allow update_devfreq to be used by devfreq governor built as modules 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: Add sysfs node for representing frequency transition information.Jonghwa Lee1-0/+101
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>
2012-11-20PM / devfreq: Add sysfs node to expose available frequenciesNishanth Menon1-0/+32
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 <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> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-20PM / devfreq: Use devm_* functions in exynos4_bus.cSachin Kamat1-30/+11
devm_* functions are device managed functions and make cleanup code simpler and smaller. devm_kzalloc and devm_regulator_get functions are used. Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> [renamed the patch title by MyungJoo Ham] Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-11-15PM / OPP: predictable fail results for opp_find* functions, v2Nishanth Menon1-2/+2
Currently the opp_find* functions return -ENODEV when: a) it cant find a device (e.g. request for an OPP search on device which was not registered) b) When it cant find a match for the search strategy used This makes life a little in-efficient for users such as devfreq to make reasonable judgement before switching search strategies. So, standardize the return results as following: -EINVAL for bad pointer parameters -ENODEV when device cannot be found -ERANGE when search fails This has the following benefit for devfreq implementation: The search fails when an unregistered device pointer is provided. This is a trigger to change the search direction and search for a better fit, however, if we cannot differentiate between a valid search range failure Vs an unregistered device, second search goes through the same fail return condition. This can be avoided by appropriate handling of error return code. With this change, we also fix devfreq for the improved search strategy with updated error code. Signed-off-by: Nishanth Menon <nm@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15PM / devfreq: make devfreq_class staticNishanth Menon1-1/+1
devfreq_class is used internally by devfreq and has no need to be globally available. This also fixes the following sparse warning: drivers/devfreq/devfreq.c:30:14: warning: symbol 'devfreq_class' was not declared. Should it be static? Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15PM / devfreq: fix sscanf handling for writable sysfs entriesNishanth Menon1-6/+3
sscanf returns 0 when an invalid parameter like: echo -n "a">min_freq is attempted. Returning back the return result(0) will cause the command not to return back to command prompt. Instead, just return -EINVAL when sscanf does not return 1. This is done for min_freq, max_freq and polling_interval Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15PM / devfreq: kernel-doc typo correctionsNishanth Menon1-11/+11
Parameter documentation needs a ':' for scripts/kernel-doc to parse properly. Minor fixes for ones warned by: ./scripts/kernel-doc -text drivers/devfreq/devfreq.c>/dev/null 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: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15PM / devfreq: Add current freq callback in device profileRajagopal Venkat1-0/+14
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>
2012-11-15PM / devfreq: Add suspend and resume apisRajagopal Venkat3-0/+39
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>
2012-11-15PM / devfreq: Core updates to support devices which can idleRajagopal Venkat6-264/+268
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>
2012-08-22workqueue: make deferrable delayed_work initializer names consistentTejun Heo1-1/+1
Initalizers for deferrable delayed_work are confused. * __DEFERRED_WORK_INITIALIZER() * DECLARE_DEFERRED_WORK() * INIT_DELAYED_WORK_DEFERRABLE() Rename them to * __DEFERRABLE_WORK_INITIALIZER() * DECLARE_DEFERRABLE_WORK() * INIT_DEFERRABLE_WORK() This patch doesn't cause any functional changes. Signed-off-by: Tejun Heo <tj@kernel.org>
2012-05-24Merge tag 'pm-for-3.5' of ↵Linus Torvalds2-0/+14
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: - Implementation of opportunistic suspend (autosleep) and user space interface for manipulating wakeup sources. - Hibernate updates from Bojan Smojver and Minho Ban. - Updates of the runtime PM core and generic PM domains framework related to PM QoS. - Assorted fixes. * tag 'pm-for-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (25 commits) epoll: Fix user space breakage related to EPOLLWAKEUP PM / Domains: Make it possible to add devices to inactive domains PM / Hibernate: Use get_gendisk to verify partition if resume_file is integer format PM / Domains: Fix computation of maximum domain off time PM / Domains: Fix link checking when add subdomain PM / Sleep: User space wakeup sources garbage collector Kconfig option PM / Sleep: Make the limit of user space wakeup sources configurable PM / Documentation: suspend-and-cpuhotplug.txt: Fix typo PM / Domains: Cache device stop and domain power off governor results, v3 PM / Domains: Make device removal more straightforward PM / Sleep: Fix a mistake in a conditional in autosleep_store() epoll: Add a flag, EPOLLWAKEUP, to prevent suspend while epoll events are ready PM / QoS: Create device constraints objects on notifier registration PM / Runtime: Remove device fields related to suspend time, v2 PM / Domains: Rework default domain power off governor function, v2 PM / Domains: Rework default device stop governor function, v2 PM / Sleep: Add user space interface for manipulating wakeup sources, v3 PM / Sleep: Add "prevent autosleep time" statistics to wakeup sources PM / Sleep: Implement opportunistic sleep, v2 PM / Sleep: Add wakeup_source_activate and wakeup_source_deactivate tracepoints ...
2012-05-01PM: devfreq: init performance/powersave governorXiaoguang Chen2-0/+14
Performance and powersave governor's get_target_freq is not called if driver chooses one of these two governors. Add init function in governor profile to call update_devfreq which will call get_target_freq subsequently. Signed-off-by: Xiaoguang Chen <chenxg@marvell.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-04-16Fix typo in various Kconfig fileMasanari Iida1-1/+1
Correct spelling typo in various Kconfig file. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-03-28Merge tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds1-115/+115
Pull "ARM: global cleanups" from Arnd Bergmann: "Quite a bit of code gets removed, and some stuff moved around, mostly the old samsung s3c24xx stuff. There should be no functional changes in this series otherwise. Some cleanups have dependencies on other arm-soc branches and will be sent in the second round. Signed-off-by: Arnd Bergmann <arnd@arndb.de>" Fixed up trivial conflicts mainly due to #include's being changes on both sides. * tag 'cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (121 commits) ep93xx: Remove unnecessary includes of ep93xx-regs.h ep93xx: Move EP93XX_SYSCON defines to SoC private header ep93xx: Move crunch code to mach-ep93xx directory ep93xx: Make syscon access functions private to SoC ep93xx: Configure GPIO ports in core code ep93xx: Move peripheral defines to local SoC header ep93xx: Convert the watchdog driver into a platform device. ep93xx: Use ioremap for backlight driver ep93xx: Move GPIO defines to gpio-ep93xx.h ep93xx: Don't use system controller defines in audio drivers ep93xx: Move PHYS_BASE defines to local SoC header file ARM: EXYNOS: Add clock register addresses for EXYNOS4X12 bus devfreq driver ARM: EXYNOS: add clock registers for exynos4x12-cpufreq PM / devfreq: update the name of EXYNOS clock registers that were omitted PM / devfreq: update the name of EXYNOS clock register ARM: EXYNOS: change the prefix S5P_ to EXYNOS4_ for clock ARM: EXYNOS: use static declaration on regarding clock ARM: EXYNOS: replace clock.c for other new EXYNOS SoCs ARM: OMAP2+: Fix build error after merge ARM: S3C24XX: remove call to s3c24xx_setup_clocks ...
2012-03-18PM / devfreq: add relation of recommended frequency.MyungJoo Ham2-8/+48
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>
2012-03-11PM / devfreq: update the name of EXYNOS clock registers that were omittedMyungJoo Ham1-3/+3
In the commit, "PM / devfreq: update the name of EXYNOS clock register" ommitted one register. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-03-11PM / devfreq: update the name of EXYNOS clock registerKukjin Kim1-112/+112
According to replacing the name of EXYNOS clock registers, this patch updates exynos4_bus.c file where it is used. Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-01-20PM / devfreq: add min/max_freq limit requested by users.MyungJoo Ham5-8/+96
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>
2012-01-20devfreq: Remove MODULE_ALIAS for exynos4 busfreq driverAxel Lin1-1/+0
This driver can only be built-in, it does not make sense to add modalias for it (in addition to being incorrect, the platform modalias needs to be prefixed with "platform:"). Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2012-01-20devfreq: exynos4_bus: Use dev_get_drvdata at appropriate placesAxel Lin1-12/+4
Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
2011-12-21Merge branch 'devfreq-for-next' of ↵Rafael J. Wysocki3-0/+1151
git://git.infradead.org/users/kmpark/linux-samsung into pm-devfreq * 'devfreq-for-next' of git://git.infradead.org/users/kmpark/linux-samsung: (765 commits) PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412. pci: Fix hotplug of Express Module with pci bridges i2c-eg20t: correct the driver init order of pch_i2c_probe() I2C: OMAP: fix FIFO usage for OMAP4 i2c-s3c2410: Fix return code of s3c24xx_i2c_parse_dt_gpio i2c: i2c-s3c2410: Add a cpu_relax() to busy wait for bus idle Linux 3.2-rc6 Revert "drm/i915: fix infinite recursion on unbind due to ilk vt-d w/a" btrfs: lower the dirty balance poll interval drm/i915/dp: Dither down to 6bpc if it makes the mode fit drm/i915: enable semaphores on per-device defaults drm/i915: don't set unpin_work if vblank_get fails drm/i915: By default, enable RC6 on IVB and SNB when reasonable iommu: Export intel_iommu_enabled to signal when iommu is in use drm/i915/sdvo: Include LVDS panels for the IS_DIGITAL check drm/i915: prevent division by zero when asking for chipset power drm/i915: add PCH info to i915_capabilities drm/i915: set the right SDVO transcoder for CPT drm/i915: no-lvds quirk for ASUS AT5NM10T-I sched: Fix select_idle_sibling() regression in selecting an idle SMT sibling ...
2011-12-20PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412.MyungJoo Ham3-0/+1151
Exynos4-bus device devfreq driver add DVFS capability for Exynos4210/4212/4412-Bus (memory). The driver monitors PPMU counters of memory controllers and adjusts operating frequencies and voltages with OPP. For Exynos4210, vdd_int is controlled. For exynos4412/4212, vdd_mif and vdd_int are controlled. Dependency (CONFIG_EXYNOS_ASV): Exynos4 ASV driver has been posted in the mailing list; however, it si not yet upstreamed. Although the current revision of Exynos4 ASV patch does not contain "CONFIG_EXYNOS_ASV", we have added the symbol to hide the dependent from compilers for now. As soon as Exynos4 ASV drivers are merged, the #ifdef statement will be removed or the name will be changed. However, enabling ASV is essential in most Exynos4 chips to reduce the power consumption of Exynos4210 because without ASV, this Devfreq driver assumes the worst case scenario, which consumes more power. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> --- Changes from v1 - Support 4212 and 4412 as well as 4210.
2011-11-24PM / devfreq: separate error paths from successful pathAxel Lin1-8/+7
I think this change improves code readability. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-15PM / devfreq: correct Kconfig dependencyMyungJoo Ham1-24/+17
Devfreq does not depend on OPP. The dependency is removed. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-15PM / devfreq: fix use after free in devfreq_remove_deviceAxel Lin1-2/+6
In devfreq_remove_device, calling _remove_devfreq will also free devfreq. Don't dereference devfreq->governor->no_central_polling after _remove_devfreq. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-11-10PM / devfreq: Remove compiler error after irq.h updateMyungJoo Ham1-0/+2
Added <linux/module.h> and <linux/stat.h> to avoid a compiler error because linux/irq.h no longer includes linux/module.h after Linux 3.2. Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-10-02PM / devfreq: Add basic governorsMyungJoo Ham6-0/+302
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>
2011-10-02PM / devfreq: Add common sysfs interfacesMyungJoo Ham1-0/+69
Device specific sysfs interface /sys/devices/.../power/devfreq_* - governor R: name of governor - cur_freq R: current frequency - polling_interval R: polling interval in ms given with devfreq profile W: update polling interval. - central_polling R: 1 if polling is managed by devfreq framework 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> -- Documentation/ABI/testing/sysfs-class-devfreq | 44 ++++++++++++++++ drivers/devfreq/devfreq.c | 69 ++++++++++++++++++++++++++ 2 files changed, 113 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-class-devfreq
2011-10-02PM: Introduce devfreq: generic DVFS framework with device-specific OPPsMyungJoo Ham4-0/+596
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>