Add driver_to_pm() helper allowing for accessing the Power Management callbacs for a particular device. Access to the callbacs (struct dev_pm_ops) is normally done through using the pm pointer that is embedded within the device_driver struct.
Helper allows for the code required to reference the pm pointer and access Power Management callbas to be simplified. Changing the following:
struct device_driver *drv = dev->driver; if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) { int ret = dev->driver->pm->prepare(dev);
To:
const struct dev_pm_ops *pm = driver_to_pm(dev->driver); if (pm && pm->prepare) { int ret = pm->prepare(dev);
Or, changing the following:
const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
To: const struct dev_pm_ops *pm = driver_to_pm(dev->driver);
Signed-off-by: Krzysztof Wilczyński kw@linux.com --- include/linux/device/driver.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/include/linux/device/driver.h b/include/linux/device/driver.h index ee7ba5b5417e..ccd0b315fd93 100644 --- a/include/linux/device/driver.h +++ b/include/linux/device/driver.h @@ -236,6 +236,21 @@ driver_find_device_by_acpi_dev(struct device_driver *drv, const void *adev) } #endif
+/** + * driver_to_pm - Return Power Management callbacs (struct dev_pm_ops) for + * a particular device. + * @drv: Pointer to a device (struct device_driver) for which you want to access + * the Power Management callbacks. + * + * Returns a pointer to the struct dev_pm_ops embedded within the device (struct + * device_driver), or returns NULL if Power Management is not present and the + * pointer is not valid. + */ +static inline const struct dev_pm_ops *driver_to_pm(struct device_driver *drv) +{ + return drv && drv->pm ? drv->pm : NULL; +} + extern int driver_deferred_probe_timeout; void driver_deferred_probe_add(struct device *dev); int driver_deferred_probe_check_state(struct device *dev);