Re: Question about failure in PCI power-state change

[Larry Finger]

On 09/08/2012 04:50 PM, Alan Stern wrote:
> On Sat, 8 Sep 2012, Rafael J. Wysocki wrote:
>
> > On Saturday, September 08, 2012, Bjorn Helgaas wrote:
> > > +cc Rafael, Huang, linux-pm
> > >
> > > On Fri, Sep 7, 2012 at 3:44 PM, Larry Finger <Larry.Finger@xxxxxxxxxxxx> wrote:
> > > > Hi,
> > > >
> > > > On occasion when I unload and reload driver rtl8192ce, I get the message
> > > >
> > > > "Refused to change power state, currently in D3"
> > > >
> > > > I added additional info to the printk and discovered that it was trying to
> > > > change to state D0. The problem seems to occur when I have made a
> > > > connection, unloaded the driver, and reloaded it. If I do not make a
> > > > connection before unloading, then the problem is a lot less likely.
> > > >
> > > > This is with kernel 3.6-rc4 from wireless-testing. A Google search shows
> > > > that the problem is usually due to suspend/resume difficulties, but this
> > > > machine has not been suspended.
> > > >
> > > > I would appreciate any help that you might give in solving this issue.
> >
> > I think writing "on" to the /sys/devices/.../power/control attribute of the device
> > in question would help.
>
> Are you suggesting that this particular wireless adapter is unable to
> return to D0 from D3?
>
> Larry, what happens if you try the suspend & resume your system while
> there's a connection?  Does a similar error occur during the resume?

After I sent this request, I found an error in the removal process for this 
particular adapter, which I suspect is the real source of the problem. That 
difficulty is only found on the new variant of the card - the older one is OK. I 
think the problem is that the adapter is left in some ill-defined state that can 
only be cleared by doing a power reset. In that state, it is unable to return to D0.

This box has never been able to suspend/resume, thus I cannot answer the other 
question.

Thanks to all that responded. Once I clean up the other error, I will recontact 
the list if the D3 => D0 problem persists.

Larry


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/