[PATCH v7] pinctrl: imx27: imx27 pincontrol driver

[mpa@pengutronix.de (Markus Pargmann)]

On Thu, Nov 07, 2013 at 10:28:01AM +0100, Lucas Stach wrote:
> Am Donnerstag, den 07.11.2013, 10:12 +0100 schrieb Markus Pargmann:
> > On Wed, Nov 06, 2013 at 10:54:02AM -0600, Matt Sealey wrote:
> [...]
> > > 
> > > Would it be so bad to implement this as a regmap and have two drivers
> > > access the same regmap on the Linux side? You don't need two nodes for
> > > that, and the IOMUX definitions can live under the GPIO node. There is
> > > NOTHING stopping two drivers on Linux matching the same compatible
> > > property. Locking and coordination in software of a single IP block
> > > used by two drivers shouldn't be arbitrated by the device tree.
> > 
> > I am not sure if it is practical to use the GPIO nodes for the IOMUX
> > driver. There are actually 6 GPIO nodes. This would lead to 6
> > iomux controllers? The different pin functions may be distributed over
> > different controllers then.
> > 
> > The first version of this series [1] was designed to have a iomux node
> > with 6 gpio subnodes.
> 
> Why was this changed? Having two different DT nodes requesting the same
> IO region is certainly the wrong thing to do.

It was suggested to map the same memory range from both drivers, so I
changed the layout completely. Perhaps it would have been better to keep
the DT node structure while not passing the memory to the gpio
subdevices.

Regards,

Markus

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