Subject: Re: [net-next PATCH 1/1] drivers: net: cpsw: Add support for new CPSW IP version

From: Richard Cochran <[email-masked]>
Date: Wed, 31 Jul 2013 18:38:46 +0200

On Wed, Jul 31, 2013 at 06:28:27PM +0300, Felipe Balbi wrote:
> On Wed, Jul 31, 2013 at 04:49:59PM +0200, Richard Cochran wrote:
> > On Wed, Jul 31, 2013 at 05:42:26PM +0530, Mugunthan V N wrote:
> > > The new IP version has a minor changes and the offsets are same as the previous
> > > version, so instead of adding CPSW version number in the driver, make the driver
> > > to fall through to the latest versions so that the new version of CPSW which has
> > > the same register offsets will work directly without patching the driver.
> > 
> > This doesn't make any sense to me. Why not just add the new version
> > number?
> > 
> > None of the hunks in your patch are on performance sensitive paths, so
> > I really can't see any point in removing the error checking.
> 
> well, if a new revision of the IP comes, the driver at least has some
> chance to work without having to be modified. If it turns out that there
> are really different features, then we patch a new version, otherwise we
> should just assume highest known version and try it out.

And if the driver reads junk from some random address due to
bootloader/DT/multikernel madness, it will happily peek and poke
around instead of rejecting the wrong version number.

Thanks,
Richard