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* Merge branch 'pm-domains' into pm-for-linusRafael J. Wysocki2011-12-251-0/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * pm-domains: PM / shmobile: Allow the A4R domain to be turned off at run time PM / input / touchscreen: Make st1232 use device PM QoS constraints PM / QoS: Introduce dev_pm_qos_add_ancestor_request() PM / shmobile: Remove the stay_on flag from SH7372's PM domains PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode ARM: S3C64XX: Implement basic power domain support PM / shmobile: Use common always on power domain governor PM / Domains: Provide an always on power domain governor PM / Domains: Fix default system suspend/resume operations PM / Domains: Make it possible to assign names to generic PM domains PM / Domains: fix compilation failure for CONFIG_PM_GENERIC_DOMAINS unset PM / Domains: Automatically update overoptimistic latency information PM / Domains: Add default power off governor function (v4) PM / Domains: Add device stop governor function (v4) PM / Domains: Rework system suspend callback routines (v2) PM / Domains: Introduce "save/restore state" device callbacks PM / Domains: Make it possible to use per-device domain callbacks
| * PM / QoS: Introduce dev_pm_qos_add_ancestor_request()Rafael J. Wysocki2011-12-251-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some devices, like the I2C controller on SH7372, are not necessary for providing power to their children or forwarding wakeup signals (and generally interrupts) from them. They are only needed by their children when there's some data to transfer, so they may be suspended for the majority of time and resumed on demand, when the children have data to send or receive. For this purpose, however, their power.ignore_children flags have to be set, or the PM core wouldn't allow them to be suspended while their children were active. Unfortunately, in some situations it may take too much time to resume such devices so that they can assist their children in transferring data. For example, if such a device belongs to a PM domain which goes to the "power off" state when that device is suspended, it may take too much time to restore power to the domain in response to the request from one of the device's children. In that case, if the parent's resume time is critical, the domain should stay in the "power on" state, although it still may be desirable to power manage the parent itself (e.g. by manipulating its clock). In general, device PM QoS may be used to address this problem. Namely, if the device's children added PM QoS latency constraints for it, they would be able to prevent it from being put into an overly deep low-power state. However, in some cases the devices needing to be serviced are not the immediate children of a "children-ignoring" device, but its grandchildren or even less direct descendants. In those cases, the entity wanting to add a PM QoS request for a given device's ancestor that ignores its children will have to find it in the first place, so introduce a new helper function that may be used to achieve that. This function, dev_pm_qos_add_ancestor_request(), will search for the first ancestor of the given device whose power.ignore_children flag is set and will add a device PM QoS latency request for that ancestor on behalf of the caller. The request added this way may be removed with the help of dev_pm_qos_remove_request() in the future, like any other device PM QoS latency request. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* | PM / Runtime: Use device PM QoS constraints (v2)Rafael J. Wysocki2011-12-011-0/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the runtime PM core use device PM QoS constraints to check if it is allowed to suspend a given device, so that an error code is returned if the device's own PM QoS constraint is negative or one of its children has already been suspended for too long. If this is not the case, the maximum estimated time the device is allowed to be suspended, computed as the minimum of the device's PM QoS constraint and the PM QoS constraints of its children (reduced by the difference between the current time and their suspend times) is stored in a new device's PM field power.max_time_suspended_ns that can be used by the device's subsystem or PM domain to decide whether or not to put the device into lower-power (and presumably higher-latency) states later (if the constraint is 0, which means "no constraint", the power.max_time_suspended_ns is set to -1). Additionally, the time of execution of the subsystem-level .runtime_suspend() callback for the device is recorded in the new power.suspend_time field for later use by the device's subsystem or PM domain along with power.max_time_suspended_ns (it also is used by the core code when the device's parent is suspended). Introduce a new helper function, pm_runtime_update_max_time_suspended(), allowing subsystems and PM domains (or device drivers) to update the power.max_time_suspended_ns field, for example after changing the power state of a suspended device. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM / QoS: Add function dev_pm_qos_read_value() (v3)Rafael J. Wysocki2011-10-041-2/+10
| | | | | | | | | | | | | | | | | | To read the current PM QoS value for a given device we need to make sure that the device's power.constraints object won't be removed while we're doing that. For this reason, put the operation under dev->power.lock and acquire the lock around the initialization and removal of power.constraints. Moreover, since we're using the value of power.constraints to determine whether or not the object is present, the power.constraints_state field isn't necessary any more and may be removed. However, dev_pm_qos_add_request() needs to check if the device is being removed from the system before allocating a new PM QoS constraints object for it, so make it use the power.power_state field of struct device for this purpose. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM QoS: Add global notification mechanism for device constraintsJean Pihet2011-08-251-0/+11
| | | | | | | | | | | | Add a global notification chain that gets called upon changes to the aggregated constraint value for any device. The notification callbacks are passing the full constraint request data in order for the callees to have access to it. The current use is for the platform low-level code to access the target device of the constraint. Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM QoS: Implement per-device PM QoS constraintsJean Pihet2011-08-251-0/+42
| | | | | | | | | | | | | | | | | | | | | | Implement the per-device PM QoS constraints by creating a device PM QoS API, which calls the PM QoS constraints management core code. The per-device latency constraints data strctures are stored in the device dev_pm_info struct. The device PM code calls the init and destroy of the per-device constraints data struct in order to support the dynamic insertion and removal of the devices in the system. To minimize the data usage by the per-device constraints, the data struct is only allocated at the first call to dev_pm_qos_add_request. The data is later free'd when the device is removed from the system. A global mutex protects the constraints users from the data being allocated and free'd. Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM QoS: Generalize and export constraints management codeJean Pihet2011-08-251-0/+14
| | | | | | | | | | | | | | | | | In preparation for the per-device constratins support: - rename update_target to pm_qos_update_target - generalize and export pm_qos_update_target for usage by the upcoming per-device latency constraints framework: * operate on struct pm_qos_constraints for constraints management, * introduce an 'action' parameter for constraints add/update/remove, * the return value indicates if the aggregated constraint value has changed, - update the internal code to operate on struct pm_qos_constraints - add a NULL pointer check in the API functions Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM QoS: Reorganize data structsJean Pihet2011-08-251-0/+19
| | | | | | | | | | | | | | In preparation for the per-device constratins support, re-organize the data strctures: - add a struct pm_qos_constraints which contains the constraints related data - update struct pm_qos_object contents to the PM QoS internal object data. Add a pointer to struct pm_qos_constraints - update the internal code to use the new data structs. Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM QoS: Minor clean-upsJean Pihet2011-08-251-11/+11
| | | | | | | | | | | | | | - Misc fixes to improve code readability: * rename struct pm_qos_request_list to struct pm_qos_request, * rename pm_qos_req parameter to req in internal code, consistenly use req in the API parameters, * update the in-kernel API callers to the new parameters names, * rename of fields names (requests, list, node, constraints) Signed-off-by: Jean Pihet <j-pihet@ti.com> Acked-by: markgross <markgross@thegnar.org> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* PM QoS: Move and rename the implementation filesJean Pihet2011-08-251-0/+61
The PM QoS implementation files are better named kernel/power/qos.c and include/linux/pm_qos.h. The PM QoS support is compiled under the CONFIG_PM option. Signed-off-by: Jean Pihet <j-pihet@ti.com> Acked-by: markgross <markgross@thegnar.org> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>