On Wed, Oct 25, 2006 at 08:49:40PM +0200, Laurent Pinchart wrote:
> Hi everybody,
> 
> I recently found out an endianess issue in a USB driver I'm developing. While 
> browsing through the USB stack code to find where the problem comes from, I 
> found what I think to be a mistake in the usb_get_device_descriptor() 
> function documentation.
> 
> /*
>  * usb_get_device_descriptor - (re)reads the device descriptor (usbcore)
>  * @dev: the device whose device descriptor is being updated
>  * @size: how much of the descriptor to read
>  * Context: !in_interrupt ()
>  *
>  * Updates the copy of the device descriptor stored in the device structure,
>  * which dedicates space for this purpose.  Note that several fields are
>  * converted to the host CPU's byte order:  the USB version (bcdUSB), and
>  * vendors product and version fields (idVendor, idProduct, and bcdDevice).
>  * That lets device drivers compare against non-byteswapped constants.
>  *
>  * Not exported, only for use by the core.  If drivers really want to read
>  * the device descriptor directly, they can call usb_get_descriptor() with
>  * type = USB_DT_DEVICE and index = 0.
>  *
>  * This call is synchronous, and may not be used in an interrupt context.
>  *
>  * Returns the number of bytes received on success, or else the status code
>  * returned by the underlying usb_control_msg() call.
>  */
> 
> After reading the code I can't find any place where the bcdUSB, idVendor, 
> idProduct and bcdDevice fields are converted to host CPU's byte order.
> 
> Could anyone confirm ? If so, the documentation should be fixed.

Yes, I forgot to update the documentation when I made the change to the
code, very sorry about that.

Please feel free to send a patch for this.

thanks,

greg k-h

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