Re: musb: dsps: make it work with two instances

[Ezequiel Garcia <ezequiel.garcia-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>]

Hi Sebastian,

On Wed, Jul 17, 2013 at 07:12:29PM +0200, Sebastian Andrzej Siewior wrote:
> 
> >After some minor DT tweaking on the current patchset,
> >I've managed to detect an USB mass storage device in the
> >second instance (host / usb1) using a Beaglebone black board.
> 
> Beaglebone black, that one has a different device tree which is not
> mainline, right?
> 

Beaglebone black it is. But I'm almost sure I just used the
am....bone.dts file that's mainlined.

I just changed the mode or something like that, very minor tweaking
indeed, altough right now I don't remember exactly which changes.

> >However, after I unplug the device, it's not recognized
> >when I replug it. Maybe you can take a look at this;
> >i'll do some more testings and see what I can come up with.
> 
> I figured out why my Host is not recognized on the second plug:
> At module load time, musb_start() is executed and it sets the
> MUSB_DEVCTL_SESSION in devctl.
> After the device is unplugged dsps_musb_try_idle() schedules a timer
> which executes the local otg_timer() function. Since the phy is in
> OTG_STATE_A_WAIT_BCON state, the MUSB_DEVCTL_SESSION bit gets removed.
> If the removal of the bit is ignored, the device is recognized after a
> re-plug.
> 

Mmmm... okey. Interesting insight, thanks!

> >Also, FWIW, I think that having a separate USB phy for am35xx would be
> >much better.
> So you would prefer a new file with 90% copy of what we already have in
> the nop_phy?
> 

No, of course not.

-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html