diff options
99 files changed, 4720 insertions, 1044 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq new file mode 100644 index 000000000000..23d78b5aab11 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-devfreq @@ -0,0 +1,52 @@ +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/.../governor +Date: September 2011 +Contact: MyungJoo Ham <myungjoo.ham@samsung.com> +Description: + The /sys/class/devfreq/.../governor shows 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. + +What: /sys/class/devfreq/.../central_polling +Date: September 2011 +Contact: MyungJoo Ham <myungjoo.ham@samsung.com> +Description: + The /sys/class/devfreq/.../central_polling shows whether + the devfreq ojbect is using devfreq-provided central + polling mechanism or not. + +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; thus. If the governor is not using + devfreq-provided central polling + (/sys/class/devfreq/.../central_polling is 0), this value + may be useless. + +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. diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 0e6a1290f04b..2af94a23a6a4 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2246,6 +2246,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. in <PAGE_SIZE> units (needed only for swap files). See Documentation/power/swsusp-and-swap-files.txt + resumedelay= [HIBERNATION] Delay (in seconds) to pause before attempting to + read the resume files + + resumewait [HIBERNATION] Wait (indefinitely) for resume device to show up. + Useful for devices that are detected asynchronously + (e.g. USB and MMC devices). + hibernate= [HIBERNATION] noresume Don't check if there's a hibernation image present during boot. diff --git a/Documentation/power/00-INDEX b/Documentation/power/00-INDEX index 45e9d4a91284..a4d682f54231 100644 --- a/Documentation/power/00-INDEX +++ b/Documentation/power/00-INDEX @@ -26,6 +26,8 @@ s2ram.txt - How to get suspend to ram working (and debug it when it isn't) states.txt - System power management states +suspend-and-cpuhotplug.txt + - Explains the interaction between Suspend-to-RAM (S3) and CPU hotplug swsusp-and-swap-files.txt - Using swap files with software suspend (to disk) swsusp-dmcrypt.txt diff --git a/Documentation/power/basic-pm-debugging.txt b/Documentation/power/basic-pm-debugging.txt index 05a7fe76232d..40a4c65f380a 100644 --- a/Documentation/power/basic-pm-debugging.txt +++ b/Documentation/power/basic-pm-debugging.txt @@ -201,3 +201,27 @@ case, you may be able to search for failing drivers by following the procedure analogous to the one described in section 1. If you find some failing drivers, you will have to unload them every time before an STR transition (ie. before you run s2ram), and please report the problems with them. + +There is a debugfs entry which shows the suspend to RAM statistics. Here is an +example of its output. + # mount -t debugfs none /sys/kernel/debug + # cat /sys/kernel/debug/suspend_stats + success: 20 + fail: 5 + failed_freeze: 0 + failed_prepare: 0 + failed_suspend: 5 + failed_suspend_noirq: 0 + failed_resume: 0 + failed_resume_noirq: 0 + failures: + last_failed_dev: alarm + adc + last_failed_errno: -16 + -16 + last_failed_step: suspend + suspend +Field success means the success number of suspend to RAM, and field fail means +the failure number. Others are the failure number of different steps of suspend +to RAM. suspend_stats just lists the last 2 failed devices, error number and +failed step of suspend. diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 3384d5996be2..646a89e0c07d 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -152,7 +152,9 @@ try to use its wakeup mechanism. device_set_wakeup_enable() affects this flag; for the most part drivers should not change its value. The initial value of should_wakeup is supposed to be false for the majority of devices; the major exceptions are power buttons, keyboards, and Ethernet adapters whose WoL -(wake-on-LAN) feature has been set up with ethtool. +(wake-on-LAN) feature has been set up with ethtool. It should also default +to true for devices that don't generate wakeup requests on their own but merely +forward wakeup requests from one bus to another (like PCI bridges). Whether or not a device is capable of issuing wakeup events is a hardware matter, and the kernel is responsible for keeping track of it. By contrast, @@ -279,10 +281,6 @@ When the system goes into the standby or memory sleep state, the phases are: time.) Unlike the other suspend-related phases, during the prepare phase the device tree is traversed top-down. - In addition to that, if device drivers need to allocate additional - memory to be able to hadle device suspend correctly, that should be - done in the prepare phase. - After the prepare callback method returns, no new children may be registered below the device. The method may also prepare the device or driver in some way for the upcoming system power transition (for diff --git a/Documentation/power/pm_qos_interface.txt b/Documentation/power/pm_qos_interface.txt index bfed898a03fc..17e130a80347 100644 --- a/Documentation/power/pm_qos_interface.txt +++ b/Documentation/power/pm_qos_interface.txt @@ -4,14 +4,19 @@ This interface provides a kernel and user mode interface for registering performance expectations by drivers, subsystems and user space applications on one of the parameters. -Currently we have {cpu_dma_latency, network_latency, network_throughput} as the -initial set of pm_qos parameters. +Two different PM QoS frameworks are available: +1. PM QoS classes for cpu_dma_latency, network_latency, network_throughput. +2. the per-device PM QoS framework provides the API to manage the per-device latency +constraints. Each parameters have defined units: * latency: usec * timeout: usec * throughput: kbs (kilo bit / sec) + +1. PM QoS framework + The infrastructure exposes multiple misc device nodes one per implemented parameter. The set of parameters implement is defined by pm_qos_power_init() and pm_qos_params.h. This is done because having the available parameters @@ -23,14 +28,18 @@ an aggregated target value. The aggregated target value is updated with changes to the request list or elements of the list. Typically the aggregated target value is simply the max or min of the request values held in the parameter list elements. +Note: the aggregated target value is implemented as an atomic variable so that +reading the aggregated value does not require any locking mechanism. + From kernel mode the use of this interface is simple: -handle = pm_qos_add_request(param_class, target_value): -Will insert an element into the list for that identified PM_QOS class with the +void pm_qos_add_request(handle, param_class, target_value): +Will insert an element into the list for that identified PM QoS class with the target value. Upon change to this list the new target is recomputed and any registered notifiers are called only if the target value is now different. -Clients of pm_qos need to save the returned handle. +Clients of pm_qos need to save the returned handle for future use in other +pm_qos API functions. void pm_qos_update_request(handle, new_target_value): Will update the list element pointed to by the handle with the new target value @@ -42,6 +51,20 @@ Will remove the element. After removal it will update the aggregate target and call the notification tree if the target was changed as a result of removing the request. +int pm_qos_request(param_class): +Returns the aggregated value for a given PM QoS class. + +int pm_qos_request_active(handle): +Returns if the request is still active, i.e. it has not been removed from a +PM QoS class constraints list. + +int pm_qos_add_notifier(param_class, notifier): +Adds a notification callback function to the PM QoS class. The callback is +called when the aggregated value for the PM QoS class is changed. + +int pm_qos_remove_notifier(int param_class, notifier): +Removes the notification callback function for the PM QoS class. + From user mode: Only processes can register a pm_qos request. To provide for automatic @@ -63,4 +86,63 @@ To remove the user mode request for a target value simply close the device node. +2. PM QoS per-device latency framework + +For each device a list of performance requests is maintained along with +an aggregated target value. The aggregated target value is updated with +changes to the request list or elements of the list. Typically the +aggregated target value is simply the max or min of the request values held +in the parameter list elements. +Note: the aggregated target value is implemented as an atomic variable so that +reading the aggregated value does not require any locking mechanism. + + +From kernel mode the use of this interface is the following: + +int dev_pm_qos_add_request(device, handle, value): +Will insert an element into the list for that identified device with the +target value. Upon change to this list the new target is recomputed and any +registered notifiers are called only if the target value is now different. +Clients of dev_pm_qos need to save the handle for future use in other +dev_pm_qos API functions. + +int dev_pm_qos_update_request(handle, new_value): +Will update the list element pointed to by the handle with the new target value +and recompute the new aggregated target, calling the notification trees if the +target is changed. + +int dev_pm_qos_remove_request(handle): +Will remove the element. After removal it will update the aggregate target and +call the notification trees if the target was changed as a result of removing +the request. + +s32 dev_pm_qos_read_value(device): +Returns the aggregated value for a given device's constraints list. + + +Notification mechanisms: +The per-device PM QoS framework has 2 different and distinct notification trees: +a per-device notification tree and a global notification tree. + +int dev_pm_qos_add_notifier(device, notifier): +Adds a notification callback function for the device. +The callback is called when the aggregated value of the device constraints list +is changed. + +int dev_pm_qos_remove_notifier(device, notifier): +Removes the notification callback function for the device. + +int dev_pm_qos_add_global_notifier(notifier): +Adds a notification callback function in the global notification tree of the +framework. +The callback is called when the aggregated value for any device is changed. + +int dev_pm_qos_remove_global_notifier(notifier): +Removes the notification callback function from the global notification tree +of the framework. + + +From user mode: +No API for user space access to the per-device latency constraints is provided +yet - still under discussion. diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 6066e3a6b9a9..0e856088db7c 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -43,13 +43,18 @@ struct dev_pm_ops { ... }; -The ->runtime_suspend(), ->runtime_resume() and ->runtime_idle() callbacks are -executed by the PM core for either the device type, or the class (if the device -type's struct dev_pm_ops object does not exist), or the bus type (if the -device type's and class' struct dev_pm_ops objects do not exist) of the given -device (this allows device types to override callbacks provided by bus types or -classes if necessary). The bus type, device |