Re: Regmap and register ranges

From: Dmitry Torokhov
Date: Fri May 17 2013 - 17:53:11 EST

On Fri, May 17, 2013 at 09:50:25PM +0100, Mark Brown wrote:
> On Fri, May 17, 2013 at 09:24:30AM -0700, Dmitry Torokhov wrote:
> > I am looking at regmap and I wonder if I am missing something with the
> > way it checks if a window crosses another range boundary or if a
> > selector is in some other window as it seem to be always tripping on
> > itself. Should we skip the current range as we iterate through them
> > and do sanity checks?
> > The setup: a device with 0x0000 - 0xffff potential register range, paged
> > in chunks of 256 registers with page selector register repeated at 0xff.
> The general idea is that the pages should be mapped in to virtual
> addresses rather than real ones so in your example you might add a
> prefix so all the registers are numbered 0x10000 to 0x1ffff. The
> physical registers and the ones inside the paged range aren't supposed
> to overlap.

The issue I have with doing an arbitrary offset is that then data
exposed in debugfs does not match the data from device's specification.

> We should probably either do sanity checks for this at init time or come
> up with a sensible way to support this in case someone does decide to do
> it, though this is the first time anyone noticed.

Does this mean you'll be open to patches allowing this scenario?


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at