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>
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>
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>
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>
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>
- 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>
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>
