diff options
Diffstat (limited to 'drivers/base')
-rw-r--r-- | drivers/base/power/runtime.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index ab3fcd9f6c98..4c7055009bd6 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -966,6 +966,30 @@ int __pm_runtime_resume(struct device *dev, int rpmflags) EXPORT_SYMBOL_GPL(__pm_runtime_resume); /** + * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter. + * @dev: Device to handle. + * + * Return -EINVAL if runtime PM is disabled for the device. + * + * If that's not the case and if the device's runtime PM status is RPM_ACTIVE + * and the runtime PM usage counter is nonzero, increment the counter and + * return 1. Otherwise return 0 without changing the counter. + */ +int pm_runtime_get_if_in_use(struct device *dev) +{ + unsigned long flags; + int retval; + + spin_lock_irqsave(&dev->power.lock, flags); + retval = dev->power.disable_depth > 0 ? -EINVAL : + dev->power.runtime_status == RPM_ACTIVE + && atomic_inc_not_zero(&dev->power.usage_count); + spin_unlock_irqrestore(&dev->power.lock, flags); + return retval; +} +EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); + +/** * __pm_runtime_set_status - Set runtime PM status of a device. * @dev: Device to handle. * @status: New runtime PM status of the device. |