[PATCH 2/3] powerpc/esdhc: add property to disable the CMD23

[Huang Changming-R66093]

> On Sep 17, 2012, at 7:36 AM, Chris Ball wrote:
> 
> > Hi,
> >
> > On Thu, Sep 13 2012, Kumar Gala wrote:
> >>>> Can you list out which SoCs support it and which don't.  Having
> >>>> this list will be useful in understanding which controller versions
> supported it.
> >>>>
> >>> P1020, p1021, p1022, p1024, p1015 and p4080 can't support it.
> >>> Mpc8536, p2020, and the other current DPAA silicon (e.g. p5020, p3041)
> support it.
> >>
> >> Based on this, why don't we use the HOSTVER register to detect instead
> of device tree:
> >
> > I've got a mild preference for handling quirk assignment in the DT
> > rather than in driver code, so I'd prefer to just push the original
> > patch to mmc-next as-is.  Does that sound okay?
> 
> Why?  I only ask because I agree with Scott that this means you have to
> update your device tree to get proper functionality.
> 
When the new silicon does not support CMD23,
if we don't update the device tree, then we must update the SDHC driver.
I prefer to add the property in device tree,
because we just add this property in new device tree, we don't need more effort to modify driver.