On Friday, June 21, 2013 10:09:15 AM Lan Tianyu wrote: > This patch updates new changes of PM QoS function. > > Signed-off-by: Lan Tianyu <tianyu.lan@xxxxxxxxx> Queued up for 3.11. Thanks, Rafael > --- > Cc linux-pm maillist > > Documentation/power/pm_qos_interface.txt | 50 +++++++++++++++++++++++++----- > 1 file changed, 43 insertions(+), 7 deletions(-) > > diff --git a/Documentation/power/pm_qos_interface.txt b/Documentation/power/pm_qos_interface.txt > index 79a2a58..4836320 100644 > --- a/Documentation/power/pm_qos_interface.txt > +++ b/Documentation/power/pm_qos_interface.txt > @@ -7,7 +7,7 @@ one of the 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. > +constraints and PM QoS flags. > > Each parameters have defined units: > * latency: usec > @@ -86,13 +86,17 @@ To remove the user mode request for a target value simply close the device > node. > > > -2. PM QoS per-device latency framework > +2. PM QoS per-device latency and flags framework > + > +For each device, there are two lists of PM QoS requests. One is maintained > +along with the aggregated target of latency value and the other is for PM QoS > +flags. Values are updated in response to changes of the request list. > + > +Target latency value is simply the minimum of the request values held in the > +parameter list elements. The PM QoS flags aggregate value is a gather (bitwise > +OR) of all list elements' values. Two device PM QoS flags are defined currently: > +PM_QOS_FLAG_NO_POWER_OFF and PM_QOS_FLAG_REMOTE_WAKEUP. > > -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. > > @@ -119,6 +123,38 @@ the request. > s32 dev_pm_qos_read_value(device): > Returns the aggregated value for a given device's constraints list. > > +enum pm_qos_flags_status dev_pm_qos_flags(device, mask) > +Check PM QoS flags of the given device against the given mask of flags. > +The meaning of the return values is as follows: > + PM_QOS_FLAGS_ALL: All flags from the mask are set > + PM_QOS_FLAGS_SOME: Some flags from the mask are set > + PM_QOS_FLAGS_NONE: No flags from the mask are set > + PM_QOS_FLAGS_UNDEFINED: The device's PM QoS structure has not been > + initialized or the list of requests is empty. > + > +int dev_pm_qos_add_ancestor_request(dev, handle, value) > +Add a PM QoS request for the first direct ancestor of the given device whose > +power.ignore_children flag is unset. > + > +int dev_pm_qos_expose_latency_limit(device, value) > +Add a request to the device's PM QoS list of latency constraints and create > +a sysfs attribute pm_qos_resume_latency_us under the device's power directory > +allowing user space to manipulate that request. > + > +void dev_pm_qos_hide_latency_limit(device) > +Drop the request added by dev_pm_qos_expose_latency_limit() from the device's > +PM QoS list of latency constraints and remove sysfs attribute pm_qos_resume_latency_us > +from the device's power directory. > + > +int dev_pm_qos_expose_flags(device, value) > +Add a request to the device's PM QoS list of flags and create sysfs attributes > +pm_qos_no_power_off and pm_qos_remote_wakeup under the device's power directory > +allowing user space to change these flags' value. > + > +void dev_pm_qos_hide_flags(device) > +Drop the request added by dev_pm_qos_expose_flags() from the device's PM QoS list > +of flags and remove sysfs attributes pm_qos_no_power_off and pm_qos_remote_wakeup > +under the device's power directory. > > Notification mechanisms: > The per-device PM QoS framework has 2 different and distinct notification trees: > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
