On Sat, 22 Jun 2024 at 13:57, Ryan Wendland wrote:
>
> When a usb device is disconnected the transfer service functions bails
> before appropraite transfer error flags are set.
(typo: "appropriate")
> This patch sets the appropriate condition code OHCI_CC_DEVICENOTRESPONDING
> when a device is disconnected and consequently has no response on the USB bus.
>
> Fixes: https://gitlab.com/qemu-project/qemu/-/issues/2081
>
> Signed-off-by: Ryan Wendland
> ---
> hw/usb/hcd-ohci.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c
> index acd6016980..8cd25d74af 100644
> --- a/hw/usb/hcd-ohci.c
> +++ b/hw/usb/hcd-ohci.c
> @@ -980,7 +980,8 @@ static int ohci_service_td(OHCIState *ohci, struct
> ohci_ed *ed)
> dev = ohci_find_device(ohci, OHCI_BM(ed->flags, ED_FA));
> if (dev == NULL) {
> trace_usb_ohci_td_dev_error();
> -return 1;
> +OHCI_SET_BM(td.flags, TD_CC, OHCI_CC_DEVICENOTRESPONDING);
> +goto exit_and_retire;
> }
> ep = usb_ep_get(dev, pid, OHCI_BM(ed->flags, ED_EN));
> if (ohci->async_td) {
> @@ -1087,6 +1088,7 @@ static int ohci_service_td(OHCIState *ohci, struct
> ohci_ed *ed)
> ed->head |= OHCI_ED_H;
> }
>
> +exit_and_retire:
> /* Retire this TD */
> ed->head &= ~OHCI_DPTR_MASK;
> ed->head |= td.next & OHCI_DPTR_MASK;
Thanks for this patch; I have a couple of questions:
(1) Do we also need to do something similar for the call in
ohci_service_iso_td() ?
(2) The error handling path for the other way we can
set the DEVICENOTRESPONDING flag also does:
* set done_count to 0
* OR in OCHI_ED_H into ed->head
Do we need to do those things here ? (My guess is "yes".)
thanks
-- PMM
