michaelh/zephyr
1
0
Fork 0
Code Releases Activity

docs: pm: Device pm fixes and enhancements

Browse source 
- idle/runtime
- Information about asynchronous calls and how to use the condition
  variable
- More details about usage count

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
This commit is contained in:
Flavio Ceolin 2021-05-10 16:28:19 -07:00 • committed by Anas Nashif
commit 62e2952a5a
1 changed files with 26 additions and 19 deletions
Download patch file Download diff file Expand all files Collapse all files

45
doc/reference/power_management/index.rst
View file

@ -376,11 +376,10 @@ Check Busy Status of All Devices API
Checks if any device is busy. The API returns 0 if no device in the system is busy. Checks if any device is busy. The API returns 0 if no device in the system is busy.
Device Idle Power Management Device Runtime Power Management
**************************** *******************************
The Device Runtime Power Management framework is an Active Power
The Device Idle Power Management framework is a Active Power
Management mechanism which reduces the overall system Power consumtion Management mechanism which reduces the overall system Power consumtion
by suspending the devices which are idle or not being used while the by suspending the devices which are idle or not being used while the
System is active or running. System is active or running.
@ -388,32 +387,32 @@ System is active or running.
The framework uses :c:func:`pm_device_state_set()` API set the The framework uses :c:func:`pm_device_state_set()` API set the
device power state accordingly based on the usage count. device power state accordingly based on the usage count.
The interfaces and APIs provided by the Device Idle PM are The interfaces and APIs provided by the Device Runtime PM are
designed to be generic and architecture independent. designed to be generic and architecture independent.
Device Idle Power Management API Device Runtime Power Management API
================================ ===================================
The Device Drivers use these APIs to perform device idle power management The Device Drivers use these APIs to perform device runtime power
operations on the devices. management operations on the devices.
Enable Device Idle Power Management of a Device API Enable Device Runtime Power Management of a Device API
--------------------------------------------------- ------------------------------------------------------
.. code-block:: c .. code-block:: c
void pm_device_enable(const struct device *dev); void pm_device_enable(const struct device *dev);
Enables Idle Power Management of the device. Enables Runtime Power Management of the device.
Disable Device Idle Power Management of a Device API Disable Device Runtime Power Management of a Device API
---------------------------------------------------- -------------------------------------------------------
.. code-block:: c .. code-block:: c
void pm_device_disable(const struct device *dev); void pm_device_disable(const struct device *dev);
Disables Idle Power Management of the device. Disables Runtime Power Management of the device.
Resume Device asynchronously API Resume Device asynchronously API
-------------------------------- --------------------------------
@ -423,7 +422,12 @@ Resume Device asynchronously API
int pm_device_get(const struct device *dev); int pm_device_get(const struct device *dev);
Marks the device as being used. This API will asynchronously Marks the device as being used. This API will asynchronously
bring the device to resume state. The API returns 0 on success. bring the device to resume state if it was suspended. If the device
was already active, it just increments the device usage count.
The API returns 0 on success.
Device drivers can monitor this operation to finish calling
:c:func:`pm_device_wait`.
Resume Device synchronously API Resume Device synchronously API
------------------------------- -------------------------------
@ -444,9 +448,12 @@ Suspend Device asynchronously API
int pm_device_put(const struct device *dev); int pm_device_put(const struct device *dev);
Marks the device as being released. This API asynchronously put Releases a device. This API asynchronously puts the device to suspend
the device to suspend state if not already in suspend state. state if not already in suspend state if the usage count of this device
The API returns 0 on success. reaches 0.
Device drivers can monitor this operation to finish calling
:c:func:`pm_device_wait`.
Suspend Device synchronously API Suspend Device synchronously API
-------------------------------- --------------------------------