| Message ID | 20170530162554.26159-6-johan@kernel.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tue, May 30, 2017 at 06:25:52PM +0200, Johan Hovold wrote: > In an attempt to work around a pinmux over-allocation issue in driver > core, commit dc5878abf49c ("usb: core: move root hub's device node > assignment after it is added to bus") moved the device-tree node > assignment until after the root hub had been registered. > > This not only makes the device-tree node unavailable to the usb driver > during probe, but also prevents the of_node from being linked to in > sysfs and causes a race with user-space for the (recently added) devspec > attribute. > > Use the new device_set_of_node_from_dev() helper to reuse the node of > the sysdev device, something which now prevents driver core from trying > to reclaim any pinctrl pins during probe. > > Fixes: dc5878abf49c ("usb: core: move root hub's device node assignment after it is added to bus") > Fixes: 51fa91475e43 ("usb/core: Added devspec sysfs entry for devices behind the usb hub") > Signed-off-by: Johan Hovold <johan@kernel.org> > --- > drivers/usb/core/hcd.c | 2 -- > drivers/usb/core/usb.c | 4 ++-- > 2 files changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c > index 5dea98358c05..2cff59e9c268 100644 > --- a/drivers/usb/core/hcd.c > +++ b/drivers/usb/core/hcd.c > @@ -1076,7 +1076,6 @@ static void usb_deregister_bus (struct usb_bus *bus) > static int register_root_hub(struct usb_hcd *hcd) > { > struct device *parent_dev = hcd->self.controller; > - struct device *sysdev = hcd->self.sysdev; > struct usb_device *usb_dev = hcd->self.root_hub; > const int devnum = 1; > int retval; > @@ -1123,7 +1122,6 @@ static int register_root_hub(struct usb_hcd *hcd) > /* Did the HC die before the root hub was registered? */ > if (HCD_DEAD(hcd)) > usb_hc_died (hcd); /* This time clean up */ > - usb_dev->dev.of_node = sysdev->of_node; > } > mutex_unlock(&usb_bus_idr_lock); > > diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c > index 62e1906bb2f3..17681d5638ac 100644 > --- a/drivers/usb/core/usb.c > +++ b/drivers/usb/core/usb.c > @@ -416,8 +416,7 @@ static void usb_release_dev(struct device *dev) > > usb_destroy_configuration(udev); > usb_release_bos_descriptor(udev); > - if (udev->parent) > - of_node_put(dev->of_node); > + of_node_put(dev->of_node); > usb_put_hcd(hcd); > kfree(udev->product); > kfree(udev->manufacturer); > @@ -616,6 +615,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, > dev->route = 0; > > dev->dev.parent = bus->controller; > + device_set_of_node_from_dev(&dev->dev, bus->sysdev); > dev_set_name(&dev->dev, "usb%d", bus->busnum); > root_hub = 1; > } else { > -- > 2.13.0 I am OK with it, but I suggest adding it for new rc1 since it is based on the 1st patch which is a bug-fix. If this one is really needed for stable tree in future, you can cherry-pick it.
On Mon, Jun 05, 2017 at 12:51:04PM +0800, Peter Chen wrote: > On Tue, May 30, 2017 at 06:25:52PM +0200, Johan Hovold wrote: > > In an attempt to work around a pinmux over-allocation issue in driver > > core, commit dc5878abf49c ("usb: core: move root hub's device node > > assignment after it is added to bus") moved the device-tree node > > assignment until after the root hub had been registered. > > > > This not only makes the device-tree node unavailable to the usb driver > > during probe, but also prevents the of_node from being linked to in > > sysfs and causes a race with user-space for the (recently added) devspec > > attribute. > > > > Use the new device_set_of_node_from_dev() helper to reuse the node of > > the sysdev device, something which now prevents driver core from trying > > to reclaim any pinctrl pins during probe. > > > > Fixes: dc5878abf49c ("usb: core: move root hub's device node assignment after it is added to bus") > > Fixes: 51fa91475e43 ("usb/core: Added devspec sysfs entry for devices behind the usb hub") > > Signed-off-by: Johan Hovold <johan@kernel.org> > I am OK with it, but I suggest adding it for new rc1 since it is based > on the 1st patch which is a bug-fix. If this one is really needed for > stable tree in future, you can cherry-pick it. I agree, and didn't intent for this one to go into 4.12-rc. Let's see how Greg wants to handle this. I'll add some comments to the cover letter in v2. Thanks, Johan
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 5dea98358c05..2cff59e9c268 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -1076,7 +1076,6 @@ static void usb_deregister_bus (struct usb_bus *bus) static int register_root_hub(struct usb_hcd *hcd) { struct device *parent_dev = hcd->self.controller; - struct device *sysdev = hcd->self.sysdev; struct usb_device *usb_dev = hcd->self.root_hub; const int devnum = 1; int retval; @@ -1123,7 +1122,6 @@ static int register_root_hub(struct usb_hcd *hcd) /* Did the HC die before the root hub was registered? */ if (HCD_DEAD(hcd)) usb_hc_died (hcd); /* This time clean up */ - usb_dev->dev.of_node = sysdev->of_node; } mutex_unlock(&usb_bus_idr_lock); diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 62e1906bb2f3..17681d5638ac 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -416,8 +416,7 @@ static void usb_release_dev(struct device *dev) usb_destroy_configuration(udev); usb_release_bos_descriptor(udev); - if (udev->parent) - of_node_put(dev->of_node); + of_node_put(dev->of_node); usb_put_hcd(hcd); kfree(udev->product); kfree(udev->manufacturer); @@ -616,6 +615,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, dev->route = 0; dev->dev.parent = bus->controller; + device_set_of_node_from_dev(&dev->dev, bus->sysdev); dev_set_name(&dev->dev, "usb%d", bus->busnum); root_hub = 1; } else {
In an attempt to work around a pinmux over-allocation issue in driver core, commit dc5878abf49c ("usb: core: move root hub's device node assignment after it is added to bus") moved the device-tree node assignment until after the root hub had been registered. This not only makes the device-tree node unavailable to the usb driver during probe, but also prevents the of_node from being linked to in sysfs and causes a race with user-space for the (recently added) devspec attribute. Use the new device_set_of_node_from_dev() helper to reuse the node of the sysdev device, something which now prevents driver core from trying to reclaim any pinctrl pins during probe. Fixes: dc5878abf49c ("usb: core: move root hub's device node assignment after it is added to bus") Fixes: 51fa91475e43 ("usb/core: Added devspec sysfs entry for devices behind the usb hub") Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/usb/core/hcd.c | 2 -- drivers/usb/core/usb.c | 4 ++-- 2 files changed, 2 insertions(+), 4 deletions(-)