Re: [PATCH] USB: ohci-omap: defer probe if PHY is missing

From: Aaro Koskinen
Date: Tue Jan 03 2017 - 15:12:32 EST


Hi,

On Tue, Jan 03, 2017 at 08:05:04PM +0100, Greg Kroah-Hartman wrote:
> On Tue, Jan 03, 2017 at 08:50:31PM +0200, Aaro Koskinen wrote:
> > On Tue, Jan 03, 2017 at 05:51:43PM +0100, Greg Kroah-Hartman wrote:
> > > On Mon, Jan 02, 2017 at 10:53:55PM +0200, Aaro Koskinen wrote:
> > > > Defer probe if PHY is missing. E.g. on Nokia 770 several modules needs
> > > > to be loaded to get the PHY going and ohci-omap should wait for those.
> > > >
> > > > Signed-off-by: Aaro Koskinen <aaro.koskinen@xxxxxx>
> > >
> > > Is this a new bug? The 770 has been around for forever, why has this
> > > not been a problem before now?
> >
> > PHY/OTG support for 770 has been around only since v3.14.
>
> 3.14 was released March, 2014. A long time ago in kernel development :)
>
> > I was previously compiling phy-tahvo as built-in, and bumped into this
> > issue when compiling it as a module.
>
> Why not just make the defconfig as built-in?

I have reverted back to using built-in in my .config.

> I'm not objecting to this patch, just really curious why no one else has
> ever hit it.

Maybe I'm the only user...

The only other board using OHCI OMAP with PHY driver is H2/H3, and they
have solved the issue making USB_OHCI_HCD_OMAP1 depend on the PHY driver:

depends on ISP1301_OMAP || !(MACH_OMAP_H2 || MACH_OMAP_H3)

This way modprobe will handle the loading order automatically.

BTW, I just realized the same issue is with omap_udc. So I guess this patch
should be just dropped, or resent so that both drivers are fixed.

A.