2013-07-09 14:03:59

by Roger Quadros

Subject: [PATCH] USB: EHCI: Fix resume signalling on remote wakeup

Set the ehci->resuming flag for the port we receive a remote
wakeup on so that resume signalling can be completed.

Without this, the root hub timer will not fire again to check
if the resume was completed and there will be a never-ending wait on
on the port.

This effect is only observed if the HUB IRQ IN does not come after we
have initiated the port resume.

Signed-off-by: Roger Quadros <[email protected]>
---
drivers/usb/host/ehci-hub.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 9ab4a4d..ca6289b 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -858,6 +858,7 @@ static int ehci_hub_control (
ehci->reset_done[wIndex] = jiffies
+ msecs_to_jiffies(20);
usb_hcd_start_port_resume(&hcd->self, wIndex);
+ set_bit(wIndex, &ehci->resuming_ports);
/* check the port again */
mod_timer(&ehci_to_hcd(ehci)->rh_timer,
ehci->reset_done[wIndex]);
--
1.7.4.1

2013-07-09 15:24:43

by Alan Stern

Subject: Re: [PATCH] USB: EHCI: Fix resume signalling on remote wakeup

On Tue, 9 Jul 2013, Roger Quadros wrote:

> Set the ehci->resuming flag for the port we receive a remote
> wakeup on so that resume signalling can be completed.
>
> Without this, the root hub timer will not fire again to check
> if the resume was completed and there will be a never-ending wait on
> on the port.
>
> This effect is only observed if the HUB IRQ IN does not come after we
> have initiated the port resume.
>
> Signed-off-by: Roger Quadros <[email protected]>
> ---
> drivers/usb/host/ehci-hub.c | 1 +
> 1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
> index 9ab4a4d..ca6289b 100644
> --- a/drivers/usb/host/ehci-hub.c
> +++ b/drivers/usb/host/ehci-hub.c
> @@ -858,6 +858,7 @@ static int ehci_hub_control (
> ehci->reset_done[wIndex] = jiffies
> + msecs_to_jiffies(20);
> usb_hcd_start_port_resume(&hcd->self, wIndex);
> + set_bit(wIndex, &ehci->resuming_ports);
> /* check the port again */
> mod_timer(&ehci_to_hcd(ehci)->rh_timer,
> ehci->reset_done[wIndex]);

Acked-by: Alan Stern <[email protected]>