On Thu, Mar 17, 2022 at 01:19:35AM +0900, Vincent Mailhol wrote:
> Rework the body of usb_maxpacket() in order not to reinvent the wheel
> and just rely on the usb_pipe_endpoint() helper function instead.
>
> Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
> ---
> include/linux/usb.h | 14 +-------------
> 1 file changed, 1 insertion(+), 13 deletions(-)
>
> diff --git a/include/linux/usb.h b/include/linux/usb.h
> index 8127782aa7a1..653d34ff0999 100644
> --- a/include/linux/usb.h
> +++ b/include/linux/usb.h
> @@ -1971,19 +1971,7 @@ usb_pipe_endpoint(struct usb_device *dev, unsigned int pipe)
>
> static inline u16 usb_maxpacket(struct usb_device *udev, int pipe)
> {
> - struct usb_host_endpoint *ep;
> - unsigned epnum = usb_pipeendpoint(pipe);
> -
> - if (usb_pipeout(pipe))
> - ep = udev->ep_out[epnum];
> - else
> - ep = udev->ep_in[epnum];
> -
> - if (!ep)
> - return 0;
> -
> - /* NOTE: only 0x07ff bits are for packet size... */
> - return usb_endpoint_maxp(&ep->desc);
> + return usb_endpoint_maxp(&usb_pipe_endpoint(udev, pipe)->desc);
The original code was careful to handle the case where ep was a NULL
pointer. What will your routine do if usb_pipe_endpoint(udev, pipe)
returns NULL?
Alan Stern
> }
>
> /* translate USB error codes to codes user space understands */
> --
> 2.34.1
>
