Re: [RFT PATCH 2/4] usb: dwc2: Do not update data length if it is 0 on inbound transfers

From: Doug Anderson
Date: Thu Feb 27 2020 - 17:07:00 EST


Hi,

On Wed, Feb 26, 2020 at 1:04 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
>
> The DWC2 documentation states that transfers with zero data length should
> set the number of packets to 1 and the transfer length to 0. This is not
> currently the case for inbound transfers: the transfer length is set to
> the maximum packet length. This can have adverse effects if the chip
> actually does transfer data as it is programmed to do. Follow chip
> documentation and keep the transfer length set to 0 in that situation.
>
> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
> drivers/usb/dwc2/hcd.c | 15 ++++++++-------
> 1 file changed, 8 insertions(+), 7 deletions(-)

I don't have any other test setup that you don't have, so just giving
my review tag and not tested tag.

I will note that it feels like this should have a "Fixes" tag or a
direct Cc to stable to make it obvious that it should make its way
back to stable trees.

Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>