On Wed, Aug 09, 2023 at 02:53:27PM +0800, Xu Yang wrote:
> If initially isoc_count = 0, periodic_count > 0 and the io watchdog is
> not started (e.g. just timed out), then the io watchdog may not run after
> submitting isoc urbs and enable_periodic(). The isoc urbs may not complete
> forever if the controller had already stopped periodic schedule.
>
> This will try to call turn_on_io_watchdog() for each enable_periodic() to
> ensure the io watchdog functions properly.
>
> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
> ---
> drivers/usb/host/ehci-sched.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
> index bd542b6fc46b..7e834587e7de 100644
> --- a/drivers/usb/host/ehci-sched.c
> +++ b/drivers/usb/host/ehci-sched.c
> @@ -490,13 +490,14 @@ static int tt_no_collision(
> static void enable_periodic(struct ehci_hcd *ehci)
> {
> if (ehci->periodic_count++)
> - return;
> + goto out;
>
> /* Stop waiting to turn off the periodic schedule */
> ehci->enabled_hrtimer_events &= ~BIT(EHCI_HRTIMER_DISABLE_PERIODIC);
>
> /* Don't start the schedule until PSS is 0 */
> ehci_poll_PSS(ehci);
> +out:
> turn_on_io_watchdog(ehci);
> }
Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
