[PATCH 1/2 v2] OMAP2/3: hwmod: fix the i2c-reset timeout during bootup

Kevin Hilman khilman at ti.com
Sat Apr 16 12:42:23 EDT 2011


On Mon, 2011-04-11 at 18:41 +0530, Avinash.H.M. wrote:
> > > > +     oh->_sysc_cache = v;
> > > > +     omap_hwmod_write(v, oh, oh->class->sysc->sysc_offs);
> > >
> > > Direct SYSCONFIG access isn't right here.   This should go through
> > > omap_hwmod.
> > >
> > > What is probably needed is exposing _ocp_softreset to device code
> > > via something like omap_hwmod_ocp_softreset() and calling that here.
> > >
> 
> Hi Kevin , 
> 
> Looking more closely, i realised that, the sequence of _ocp_softreset
> doesn't work for I2C. It has a special programming sequence which needs
> to be followed to reset the IP. That was the reason, we created
> omap_i2c_reset.  So i feel we need not expose _ocp_softreset.
> 
> Since, the problem here is accessing the SYSCONFIG here, instead, what i
> can do is, something like below.
> 
> 	omap_hwmod_softreset(struct omap_hwmod *oh)
> 	{
> 
> 		v = oh->_sysc_cache;
> 		v |= (0x1 << oh->class->sysc->sysc_fields->srst_shift);
> 
> 		oh->_sysc_cache = v;
> 		omap_hwmod_write(v, oh, oh->class->sysc->sysc_offs);
> 
> 	}
> 
> And then call this in omap_i2c_reset. Is this OK ?

Yes, sounds reasonable.

Please be sure to describe the reasoning above in the changelog as well.

Thanks,

Kevin





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