[PATCH 02/12] mmci: fix multi block transfers

Russell King - ARM Linux linux at arm.linux.org.uk
Thu Jul 29 10:14:07 EDT 2010

On Thu, Jul 29, 2010 at 02:55:11PM +0100, Russell King - ARM Linux wrote:
> On Thu, Jul 29, 2010 at 02:42:39PM +0100, Colin Tuckley wrote:
> > > However, I think this will make GPIO on Realview wrong - iirc, the card
> > > detection bits from PL061 are inverted.
> > 
> > See above.
> I've no idea what the right thing on Realview is because the documentation
> is too poor in this area.  Although the Realview EB user manual gives you
> the GPIO block signals, it doesn't say what sense they are.
> It looks to me from the hardware description diagrams, that the GPIO block
> is fed with an inverted signal from the socket card detect pin - which
> itself is active low.  That means the GPIO signal is in a positive logic
> state.
> So I don't think that the "return !status;" is right even for the GPIO
> case.

Hmm.  Firstly, Versatile doesn't support reading the card detect via GPIO.

Secondly, my Realview hardware appears to have the GPIO card detect status
inverted - zero means card inserted, non-zero means card removed.  That's
contary to what the documentation suggests.


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