[PATCH v2 08/10] PM core: Fix restoring devices with links during system PM transition
From: m.szyprowski@samsung.com (Marek Szyprowski)
Date: 2016-06-17 06:29:29
Also in:
linux-iommu, linux-pm, linux-samsung-soc, lkml
Subsystem:
driver core, kobjects, debugfs and sysfs, hibernation (aka software suspend, aka swsusp), power management core, suspend to ram, the rest · Maintainers:
Greg Kroah-Hartman, "Rafael J. Wysocki", Danilo Krummrich, Linus Torvalds
When devices are being runtime resumed during the system PM transition to suspend state, the link suppliers might be already resumed and have runtime pm disabled. This is normal case. This patch adds special support for such case. Simple call to pm_runtime_get_syncreturns error when device has runtime PM disabled, what results in incorrect runtime PM state during system wide PM transition. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- drivers/base/power/runtime.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 0ea00d442e0f..d00b079fad88 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c@@ -261,6 +261,26 @@ static int rpm_check_suspend_allowed(struct device *dev) } /** + * __pm_runtime_force_resume - force resume of the device + * @dev: Device to resume + * + * This function works like __pm_runtime_resume(dev, RPM_GET_PUT), but + * also handles devices with runtime PM disabled. This allows to properly + * control all devices during preparation for system PM transition. + */ +static int __pm_runtime_force_resume(struct device *dev) +{ + if (!dev->power.disable_depth) + return pm_runtime_get_sync(dev); + + if (dev->power.runtime_status != RPM_ACTIVE || + atomic_inc_not_zero(&dev->power.usage_count) == 0) + return -EINVAL; + + return 0; +} + +/** * __rpm_callback - Run a given runtime PM callback for a given device. * @cb: Runtime PM callback to run. * @dev: Device to run the callback for.
@@ -291,7 +311,7 @@ static int __rpm_callback(int (*cb)(struct device *), struct device *dev) if ((link->flags & DEVICE_LINK_PM_RUNTIME) && link->status != DEVICE_LINK_SUPPLIER_UNBIND && !link->rpm_active) { - retval = pm_runtime_get_sync(link->supplier); + retval = __pm_runtime_force_resume(link->supplier); if (retval < 0) { pm_runtime_put_noidle(link->supplier); goto fail;
--
1.9.1