On Fri, 8 Apr 2011, Sebastian Andrzej Siewior wrote:
> * Alan Stern | 2011-03-18 21:27:15 [-0400]:
>
> >On Fri, 18 Mar 2011, Paul Zimmerman wrote:
> >
> >> > --- a/drivers/usb/gadget/audio.c
> >> > +++ b/drivers/usb/gadget/audio.c
> >> > @@ -52,7 +52,7 @@ static struct usb_device_descriptor device_desc = {
> >> > .bLength = sizeof device_desc,
> >> > .bDescriptorType = USB_DT_DEVICE,
> >> >
> >> > - .bcdUSB = __constant_cpu_to_le16(0x200),
> >> > + .bcdUSB = cpu_to_le16(0x0300),
> >> >
> >> > .bDeviceClass = USB_CLASS_PER_INTERFACE,
> >> > .bDeviceSubClass = 0,
> >>
> >> This won't work. Now the gadget will not be recognized by a USB 2.0
> >> host.
> >
> >Why not? I'm not aware of any hosts that will refuse to work with a
> >device merely because the bcdUSB field says 0x0300 instead of 0x0200.
>
> Quote from ch 9.2.6.6:
> |Devices with a value of at least 0210H in the bcdUSB field of their
> |device descriptor shall support GetDescriptor (BOS Descriptor) requests.
>
> The device can't handle the GetDescriptor (BOS) yet. I don't know if
> "shall" means "must" or "should".
It does seem premature to change the bcdUSB field until support has
been added for all the new descriptors.
Alan Stern
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