Re: 2.5.69 Interrupt Latency

[Greg KH]

On Wed, May 14, 2003 at 04:06:33PM -0500, Paul Fulghum wrote:
> On Tue, 2003-05-13 at 13:11, Greg KH wrote:
> 
> I was looking over the PIIX3 datasheet and noticed
> that the USBSTS_RD bit is only valid when the
> device is in the suspended state.
> 
> This bit is being acted on regardless of the
> suspend state of the controller in the ISR.
> Could this be why the driver is detecting
> false 'resume' signals and calling wakeup_hc()
> when it shouldn't?
> 
> Maybe the code should be something like:
> 
> if (uhci->is_suspended && (status & USBSTS_RD))
> 	wakeup_hc(uhci);

That's basically what the code I sent you did :)

> in the ISR to qualify acting on that status bit.
> Alternatively, USBCMD_EGSM (BIT3) of the USBCMD
> register could be tested to qualify action on
> the state of USBSTS_RD
> 
> I'm going to test this now, but I wanted to
> know what you think.

I think it's correct, but I don't think it will solve your problem.  I
would be very happy to be wrong though.

thanks,

greg k-h