Re: [PATCH] usb: dwc3: gadget: fix high-speed multiplier setting

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Jun 30, 2022 at 04:02:16PM +0200, Michael Grzeschik wrote:
> For high-speed transfers the __dwc3_prepare_one_trb function is
> calculating the multiplier setting for the trb based on the length of
> the trb currently prepared. This assumption is wrong. For trbs with a
> sglist the length of the actual request has to be taken instead.
> 
> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
> ---
>  drivers/usb/dwc3/gadget.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 8716bece107208..0fc3ecfaa48baf 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -1186,7 +1186,7 @@ static void __dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_trb *trb,
>  		dma_addr_t dma, unsigned int length, unsigned int chain,
>  		unsigned int node, unsigned int stream_id,
>  		unsigned int short_not_ok, unsigned int no_interrupt,
> -		unsigned int is_last, bool must_interrupt)
> +		unsigned int is_last, bool must_interrupt, int req_length)

Why not put this right next to 'length'?

And wow, that's a crazy number of options for a function.  Why is this
even a separate function at all?  Why can't it just be in
dwc3_prepare_one_trb() as that's the only place this is called?

thanks,

greg k-h