| Message ID | 1434362256-239992-4-git-send-email-andriy.shevchenko@linux.intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On Mon, Jun 15, 2015 at 11:57 AM, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > From: "Rafael J. Wysocki" <rjw@rjwysocki.net> > > If the parent is still suspended when driver probe is > attempted, the result may be failure. > > For example, if the parent is a PCI MFD device that has been > suspended when we try to probe our device, any register > reads will return 0xffffffff. > > To fix the problem, making sure the parent is always awake > before attempting driver probe. > > Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net> Please use my Intel sign-off with this one: Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > drivers/base/dd.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/drivers/base/dd.c b/drivers/base/dd.c > index e843fdb..c4c1eaf 100644 > --- a/drivers/base/dd.c > +++ b/drivers/base/dd.c > @@ -399,6 +399,8 @@ EXPORT_SYMBOL_GPL(wait_for_device_probe); > * > * This function must be called with @dev lock held. When called for a > * USB interface, @dev->parent lock must be held as well. > + * > + * If the device has a parent, runtime-resume the parent before driver probing. > */ > int driver_probe_device(struct device_driver *drv, struct device *dev) > { > @@ -410,10 +412,16 @@ int driver_probe_device(struct device_driver *drv, struct device *dev) > pr_debug("bus: '%s': %s: matched device %s with driver %s\n", > drv->bus->name, __func__, dev_name(dev), drv->name); > > + if (dev->parent) > + pm_runtime_get_sync(dev->parent); > + > pm_runtime_barrier(dev); > ret = really_probe(dev, drv); > pm_request_idle(dev); > > + if (dev->parent) > + pm_runtime_put(dev->parent); > + > return ret; > } > > @@ -459,8 +467,14 @@ int device_attach(struct device *dev) > ret = 0; > } > } else { > + if (dev->parent) > + pm_runtime_get_sync(dev->parent); > + > ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); > pm_request_idle(dev); > + > + if (dev->parent) > + pm_runtime_put(dev->parent); > } > out_unlock: > device_unlock(dev); > -- > 2.1.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/base/dd.c b/drivers/base/dd.c index e843fdb..c4c1eaf 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -399,6 +399,8 @@ EXPORT_SYMBOL_GPL(wait_for_device_probe); * * This function must be called with @dev lock held. When called for a * USB interface, @dev->parent lock must be held as well. + * + * If the device has a parent, runtime-resume the parent before driver probing. */ int driver_probe_device(struct device_driver *drv, struct device *dev) { @@ -410,10 +412,16 @@ int driver_probe_device(struct device_driver *drv, struct device *dev) pr_debug("bus: '%s': %s: matched device %s with driver %s\n", drv->bus->name, __func__, dev_name(dev), drv->name); + if (dev->parent) + pm_runtime_get_sync(dev->parent); + pm_runtime_barrier(dev); ret = really_probe(dev, drv); pm_request_idle(dev); + if (dev->parent) + pm_runtime_put(dev->parent); + return ret; } @@ -459,8 +467,14 @@ int device_attach(struct device *dev) ret = 0; } } else { + if (dev->parent) + pm_runtime_get_sync(dev->parent); + ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); pm_request_idle(dev); + + if (dev->parent) + pm_runtime_put(dev->parent); } out_unlock: device_unlock(dev);