On Sat, 20 Nov 2010, Matthew Garrett wrote:
> The AMD SB700 I'm testing with wakes up fine on connection after runtime
> suspend, but doesn't appear to set the "Port change detect" bit in USBSTS.
> The change does appear in the individual port register, so try checking
> the port status as well. It's an infrequent enough operation that the
> overhead shouldn't be an issue.
>
> Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx>
> ---
>
> Just a couple of formatting cleanups
>
> drivers/usb/host/ehci-hub.c | 15 ++++++++++++++-
> 1 files changed, 14 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
> index 796ea0c..460096b 100644
> --- a/drivers/usb/host/ehci-hub.c
> +++ b/drivers/usb/host/ehci-hub.c
> @@ -106,6 +106,17 @@ static void ehci_handover_companion_ports(struct ehci_hcd *ehci)
> ehci->owned_ports = 0;
> }
>
> +static int ehci_port_change(struct ehci_hcd *ehci)
> +{
> + int i = HCS_N_PORTS(ehci->hcs_params);
> +
> + while (i--)
> + if (ehci_readl(ehci, &ehci->regs->port_status[i]) & PORT_CSC)
> + return 1;
> +
> + return 0;
> +}
> +
> static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
> bool suspending, bool do_wakeup)
> {
> @@ -168,7 +179,9 @@ static void ehci_adjust_port_wakeup_flags(struct ehci_hcd *ehci,
> }
>
> /* Does the root hub have a port wakeup pending? */
> - if (!suspending && (ehci_readl(ehci, &ehci->regs->status) & STS_PCD))
> + if (!suspending &&
> + ((ehci_readl(ehci, &ehci->regs->status) & STS_PCD) ||
> + ehci_port_change(ehci)))
> usb_hcd_resume_root_hub(ehci_to_hcd(ehci));
> }
The code itself is fine, but please add a comment explaining why this
is needed. Putting the explanation into the commit description isn't
enough because people reading the code won't see it.
Alan Stern
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
