Re: Patch mceusb: fix invalid urb interval

[Mauro Carvalho Chehab <m.chehab@samsung.com>]

Em Sun, 10 Nov 2013 10:50:45 +0000 (UTC)
Martin Kittel <linux@martin-kittel.de> escreveu:

> Hi,
> 
> I had trouble getting my MCE remote control to work on my new Intel
> mainboard. It was working fine with older boards but with the new board
> there would be no reply from the remote just after the setup package was
> received during the init phase.
> I traced the problem down to the mceusb_dev_recv function where the received
> urb is resubmitted again. The problem is that my new board is so blazing
> fast that the initial urb was processed in less than a single 125
> microsecond interval, so the urb as it was received had urb->interval set to 0.
> As the urb is just resubmitted as it came in it now had an invalid interval
> set and was rejected.
> The patch just resets urb->interval to its initial value and adds some error
> diagnostics (which would have saved me a lot of time during my analysis).
> 
> Any comment is welcome.
> 
> Best wishes,

You forgot to send your signed-off-by:
> 
> Martin.
> 
> 
> diff --git a/drivers/media/rc/mceusb.c b/drivers/media/rc/mceusb.c
> index 3c76101..c5313cb 100644
> --- a/drivers/media/rc/mceusb.c
> +++ b/drivers/media/rc/mceusb.c
> @@ -1030,7 +1030,7 @@ static void mceusb_process_ir_data(struct mceusb_dev *ir
>  static void mceusb_dev_recv(struct urb *urb)
>  {
>         struct mceusb_dev *ir;
> -       int buf_len;
> +       int buf_len, res;
>  

Please use tabs and not spaces. Note: This could be something wrong with your
emailer that could be mangling whitespaces.


>         if (!urb)
>                 return;
> @@ -1067,7 +1067,11 @@ static void mceusb_dev_recv(struct urb *urb)
>                 break;
>         }
>  
> -       usb_submit_urb(urb, GFP_ATOMIC);
> +       urb->interval = ir->usb_ep_out->bInterval; /* reset urb interval */
> +       res = usb_submit_urb(urb, GFP_ATOMIC);
> +       if (res) {
> +               mce_dbg(ir->dev, "restart request FAILED! (res=%d)\n", res);
> +       }

No need for braces here. Just do:
+	if (res)
+		mce_dbg(ir->dev, "restart request FAILED! (res=%d)\n", res);

>  }

>  
>  static void mceusb_get_emulator_version(struct mceusb_dev *ir)
> 
> 
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-- 

Cheers,
Mauro