[alsa-devel] [PATCH] sound/soc: rename vol to volatile_register as appropriate

Mark Brown broonie at opensource.wolfsonmicro.com
Wed Oct 13 14:33:01 CEST 2010

On Wed, Oct 13, 2010 at 05:10:45AM -0700, Joe Perches wrote:
> Rename the declaration and uses of variables
> named vol to volatile_register to avoid name
> clash with the much more common use of vol
> for volume.

Are any of the contexts actually ambiguous?  I have to say I don't find
this useful.  If the register I/O code knows anything about volumes I'd
say we've probably messed up somewhere.

> > > static struct {
> > > 	bool readable;
> > > 	bool writable,
> > > 	bool vol;
> > > } etc...

> > The readable and writable fields are being used as bitmasks:

> No, they are being declared as bitmasks.
> writable is used once as bool, readable isn't used at all.

They're being used in the table initialisation.

> > | +       { 0x1F, 0x1F, 1 }, /* 03 battery voltage */

> > so this discards data which we may wish to use in future.

> It's not used as bitmask now, what use would there
> be in the future for it as a bitmask?

Examples would include validating I/O operations done by drivers, or
supporting fancy cache handling that pays attention to things per bit.

> > vol is traditionally used for this throughout the subsystem.  It's
> > unfortuante that volatile is a keyword.

> As far as I see, your description of vol being
> used throughout the subsystem is not true.

I'm sorry?  It's used as the field name for volatility in all the
drivers I can remember that use a table to look volatility up in
register properties.

More information about the Alsa-devel mailing list