On Mon, Feb 24, 2014 at 12:44:46PM -0500, Alan Stern wrote: > On Mon, 24 Feb 2014, Mathias Nyman wrote: > > > xHCI driver has its own pci probe function that will call usb_hcd_pci_probe > > to register its usb-2 bus, and then continue to manually register the > > usb-3 bus. usb_hcd_pci_probe does a pm_runtime_put_noidle at the end and > > might thus trigger a runtime suspend before the usb-3 bus is ready. > > > > Prevent the runtime suspend by increasing the usage count in the > > beginning of xhci_pci_probe, and decrease it once the usb-3 bus is > > ready. > > > > xhci-platform driver is not using usb_hcd_pci_probe to set up > > busses and should not need to have it's usage count increased during probe. > > > > Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> > > --- > > drivers/usb/host/xhci-pci.c | 11 ++++++++++- > > 1 file changed, 10 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c > > index 04f986d..ea7158b 100644 > > --- a/drivers/usb/host/xhci-pci.c > > +++ b/drivers/usb/host/xhci-pci.c > > @@ -190,6 +190,10 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) > > struct usb_hcd *hcd; > > > > driver = (struct hc_driver *)id->driver_data; > > + > > + /* Prevent USB-2 roothub runtime suspend until USB-3 is initialized. */ > > + pm_runtime_get_noresume(&dev->dev); > > Strictly speaking, this prevents the _controller_ from going into > runtime suspend -- not the root hub. Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Mathias, want to fix this comment and queue this up to Greg? It should probably be marked for stable. > Apart from nit about the comment, > > Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
