driver core / PM: Add PM domain callbacks for device setup/cleanup

If PM domains are in use, it may be necessary to prepare the code
handling a PM domain for driver probing.  For example, in some
cases device drivers rely on the ability to power on the devices
with the help of the IO runtime PM framework and the PM domain
code needs to be ready for that.  Also, if that code has not been
fully initialized yet, the driver probing should be deferred.

Moreover, after the probing is complete, it may be necessary to
put the PM domain in question into the state reflecting the current
needs of the devices in it, for example, so that power is not drawn
in vain.  The same should be done after removing a driver from
a device, as the PM domain state may need to be changed to reflect
the new situation.

For these reasons, introduce new PM domain callbacks, ->activate,
->sync and ->dismiss called, respectively, before probing for a
device driver, after the probing has completed successfully and
if the probing has failed or the driver has been removed.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index cdc779cf79a3..aeb744891e44 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -298,6 +298,12 @@ static int really_probe(struct device *dev, struct device_driver *drv)
                 goto probe_failed;
         }
 
+        if (dev->pm_domain && dev->pm_domain->activate) {
+                ret = dev->pm_domain->activate(dev);
+                if (ret)
+                        goto probe_failed;
+        }
+
         if (dev->bus->probe) {
                 ret = dev->bus->probe(dev);
                 if (ret)
@@ -308,6 +314,9 @@ static int really_probe(struct device *dev, struct device_driver *drv)
                         goto probe_failed;
         }
 
+        if (dev->pm_domain && dev->pm_domain->sync)
+                dev->pm_domain->sync(dev);
+
         driver_bound(dev);
         ret = 1;
         pr_debug("bus: '%s': %s: bound device %s to driver %s\n",
@@ -319,6 +328,8 @@ probe_failed:
         driver_sysfs_remove(dev);
         dev->driver = NULL;
         dev_set_drvdata(dev, NULL);
+        if (dev->pm_domain && dev->pm_domain->dismiss)
+                dev->pm_domain->dismiss(dev);
 
         if (ret == -EPROBE_DEFER) {
                 /* Driver requested deferred probing */
@@ -525,6 +536,9 @@ static void __device_release_driver(struct device *dev)
                 devres_release_all(dev);
                 dev->driver = NULL;
                 dev_set_drvdata(dev, NULL);
+                if (dev->pm_domain && dev->pm_domain->dismiss)
+                        dev->pm_domain->dismiss(dev);
+
                 klist_remove(&dev->p->knode_driver);
                 if (dev->bus)
                         blocking_notifier_call_chain(&dev->bus->p->bus_notifier,