Re: [patch 2/2] support for UHCI suspend / remote wake up

Marcelo Tosatti
2010-12-01T17:11:05Z

On Wed, Dec 01, 2010 at 04:12:14PM +0100, Gerd Hoffmann wrote:
> On 11/25/10 18:04, Marcelo Tosatti wrote:
> >This patch enables USB UHCI global suspend/resume feature. The OS will
> >stop the HC once all ports are suspended. If there is activity on the
> >port(s), an interrupt signalling remote wakeup will be triggered.
> >
> >To enable autosuspend for the USB tablet on Linux guests:
> >
> >echo auto> /sys/devices/pci0000:00/0000:00:01.2/usb1/1-1/power/level
>
> Hmm, did you ever got this working sanely?

Yes. Linux and Windows.

> /me sees bus disconnects in the guest ...

I was seeing bus disconnects when not clearing port resume bit properly.

> > port->ctrl&= ~(val& 0x000a);
> >+ port->ctrl&= ~(port->ctrl& 0x0040); /* clear port resume detected */
> > }
>
> This chunk looks suspicious ...
>
> I suspect the port suspend/resume emulation isn't complete.
>
> /me goes debugging,
> Gerd

CONFIG_USB_DEBUG helps.