Re: 2.6.31-rc2 warning in drivers/usb/host/ehci-hcd.c

From: Carlos R. Mafra
Date: Tue Jul 07 2009 - 17:28:21 EST


On Tue 7.Jul'09 at 15:58:24 -0400, Alan Stern wrote:
> > PS: I don't know if it is related, but I can't connect anymore
> > after s2ram. 'draknetcenter' says that /dev/ttyUSB1 could not
> > be openned (but I need to make more tests to provide more info)...
>
> That's a separate issue. We can explore it in greater depth if you
> want.
>
> For now, here's a patch to fix the driver. I don't know why the
> usb_clear_halt call was in there; it doesn't appear to serve any useful
> purpose. Let me know how well the patch works.

The patch works fine and the warning is gone now. Consider it tested.

Furthermore it also fixed somehow the non-working state
after s2ram! I suspended to RAM while it was connected and
it resumed just fine, no warnings and it was still connected.

Thank you very much for your fix^2!

> Alan Stern
>
>
>
> Index: usb-2.6/drivers/usb/serial/option.c
> ===================================================================
> --- usb-2.6.orig/drivers/usb/serial/option.c
> +++ usb-2.6/drivers/usb/serial/option.c
> @@ -931,23 +931,11 @@ static int option_open(struct tty_struct
>
> dbg("%s", __func__);
>
> - /* Reset low level data toggle and start reading from endpoints */
> + /* Start reading from the IN endpoint */
> for (i = 0; i < N_IN_URB; i++) {
> urb = portdata->in_urbs[i];
> if (!urb)
> continue;
> - if (urb->dev != serial->dev) {
> - dbg("%s: dev %p != %p", __func__,
> - urb->dev, serial->dev);
> - continue;
> - }
> -
> - /*
> - * make sure endpoint data toggle is synchronized with the
> - * device
> - */
> - usb_clear_halt(urb->dev, urb->pipe);
> -
> err = usb_submit_urb(urb, GFP_KERNEL);
> if (err) {
> dbg("%s: submit urb %d failed (%d) %d",
> @@ -956,16 +944,6 @@ static int option_open(struct tty_struct
> }
> }
>
> - /* Reset low level data toggle on out endpoints */
> - for (i = 0; i < N_OUT_URB; i++) {
> - urb = portdata->out_urbs[i];
> - if (!urb)
> - continue;
> - urb->dev = serial->dev;
> - /* usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
> - usb_pipeout(urb->pipe), 0); */
> - }
> -
> option_send_setup(port);
>
> return 0;
--
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