On Tue, 2011-01-11 at 11:09 -0500, Alan Stern wrote:
> On Mon, 10 Jan 2011, Dan Williams wrote:
>
> > > > > What serial driver is getting bound to your interface? Is it cdc-acm?
> > > >
> > > > qcaux, which is a thin shim driver over usbserial, much like moto_modem.
> > > > It's basically a driver to expose the Qualcomm DIAG protocol ports on
> > > > devices that present a CDC-ACM interface (for standard AT commands) and
> > > > then a separate Qualcomm DIAG interface. Thus more than one driver gets
> > > > bound to the device; CDC-ACM for the actual CDC-ACM interface, and qcaux
> > > > for the DIAG interface, and possibly another driver for other protocols
> > > > the device may support on the other interfaces.
> > >
> > > ... but maybe something's wrong with qcaux. I'll have a look at it
> > > tomorrow.
> >
> > qcaux.c does not have:
> >
> > #ifdef CONFIG_PM
> > .suspend = usb_serial_suspend,
> > .resume = usb_serial_resume,
> > .supports_autosuspend = 1,
> > #endif
> >
> > but that shouldn't mean that open() fails, I hope. If the driver
> > doesn't support autosuspend, things should still work... Regardless,
> > adding that hunk to qcaux causes things to magically work again.
>
> It isn't needed.
>
> > What's the criteria for drivers to set supports_autosuspend = 1? Should
> > everything that uses usb_serial_probe() be audited with an eye towards
> > adding that block?
>
> No, that's not the problem. The problem is that qcaux.c does not
> define the .usb_driver field in its qcaux_device structure.
>
> Hmm, it looks like the same bug is present for the epic_device
> structure in io_tables.h, and in iuu_phoenix.c, keyspan.h,
> moto_modem.c, oti6858.c, siemens_mpi.c, spcp8x5.c, and usb_debug.c.
> Maybe it would be a good idea to replace the test in
> usb_serial_register() for this field being non-NULL with a BUG. That
> would draw people's attention!
Which makes sense since I originally copied moto_modem.c for qcaux...
This patch to qcaux.c works:
@@ -83,6 +84,7 @@ static struct usb_serial_driver qcaux_device = {
.owner = THIS_MODULE,
.name = "qcaux",
},
+ .usb_driver = &qcaux_driver,
.id_table = id_table,
.num_ports = 1,
};
So I think you've hit the nail on the head. Thanks for the help!
Dan
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