[U-Boot] [PATCH RFC] usb: Prevent using reserved registers on DM36x usb

[Marek Vasut <marex@denx.de>]

Dear Andrew Murray,
> 
> > The musb driver defines and uses MUSB_CSR0_H_DIS_PING, however this
> > bit is reserved on the DM36x. Thus this patch ensures that the
> > reserved bit is not accesssed.
> > 
> > It has been observed that some USB devices will fail to enumerate
> > with errors such as 'error in inquiry' without this patch.
> > 
> > See http://www.ti.com/litv/pdf/sprufh9a for details.
> > 
> > Cc: Marek Vasut <marex@denx.de>
> > Cc: Tom Rini <trini@ti.com>
> > Signed-off-by: Andrew Murray <amurray@embedded-bits.co.uk>
> > ---
> > 
> >  drivers/usb/musb/musb_core.h |    4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h
> > index ec8a038..c9a9d66 100644
> > --- a/drivers/usb/musb/musb_core.h
> > +++ b/drivers/usb/musb/musb_core.h
> > @@ -216,7 +216,11 @@ struct musb_regs {
> > 
> >  #define MUSB_CSR0_P_SENTSTALL	0x0004
> >  
> >  /* CSR0 in Host mode */
> > 
> > +#if defined(CONFIG_SOC_DM365)
> > +#define MUSB_CSR0_H_DIS_PING		0x0000
> > +#else
> > 
> >  #define MUSB_CSR0_H_DIS_PING		0x0800
> > 
> > +#endif
> > 
> >  #define MUSB_CSR0_H_WR_DATATOGGLE	0x0400	/* Set to allow setting: */
> >  #define MUSB_CSR0_H_DATATOGGLE		0x0200	/* Data toggle control
> 
> */
> 
> >  #define MUSB_CSR0_H_NAKTIMEOUT		0x0080
> 
> It would be much nicer if you avoided using this bit in musb_hcd.c instead
> of hacking it like this.

Bump? Will we get a V2 here ?

Best regards,
Marek Vasut