| Message ID | 1505742050-5697-8-git-send-email-bmeng.cn@gmail.com |
|---|---|
| State | Accepted |
| Delegated to: | Marek Vasut |
| Headers | show |
| Series | usb: xhci: Add interrupt transfer support and full speed device support | expand |
On 18.09.2017 15:40, Bin Meng wrote: > For xHCI it is not possible to read a device descriptor before it > has been assigned an address. That's why usb_setup_descriptor() > was called with 'do_read' being false. But we really need try to > read the device descriptor before starting any real communication > with the default control endpoint. > > Signed-off-by: Bin Meng <bmeng.cn@gmail.com> > --- > > common/usb.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/common/usb.c b/common/usb.c > index 88cee81..8d27bc7 100644 > --- a/common/usb.c > +++ b/common/usb.c > @@ -1052,6 +1052,17 @@ static int usb_prepare_device(struct usb_device *dev, int addr, bool do_read, > > mdelay(10); /* Let the SET_ADDRESS settle */ > > + /* > + * If we haven't read device descriptor before, read it here > + * after device is assigned an address. This is only applicable > + * to xHCI so far. > + */ > + if (!do_read) { > + err = usb_setup_descriptor(dev, true); > + if (err) > + return err; > + } > + > return 0; > } > > Reviewed-by: Stefan Roese <sr@denx.de> Tested-by: Stefan Roese <sr@denx.de> Thanks, Stefan
diff --git a/common/usb.c b/common/usb.c index 88cee81..8d27bc7 100644 --- a/common/usb.c +++ b/common/usb.c @@ -1052,6 +1052,17 @@ static int usb_prepare_device(struct usb_device *dev, int addr, bool do_read, mdelay(10); /* Let the SET_ADDRESS settle */ + /* + * If we haven't read device descriptor before, read it here + * after device is assigned an address. This is only applicable + * to xHCI so far. + */ + if (!do_read) { + err = usb_setup_descriptor(dev, true); + if (err) + return err; + } + return 0; }
For xHCI it is not possible to read a device descriptor before it has been assigned an address. That's why usb_setup_descriptor() was called with 'do_read' being false. But we really need try to read the device descriptor before starting any real communication with the default control endpoint. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> --- common/usb.c | 11 +++++++++++ 1 file changed, 11 insertions(+)