Re: abx80x: RV-1805 initialization order correct?

["Kevin P. Fleming" <kevin+linux@km6g.us>]

OK, thanks, I'll update my system to explicitly indicate that the
rv1805 is being used in the device tree.

On Sat, May 30, 2020 at 4:25 PM Alexandre Belloni
<alexandre.belloni@bootlin.com> wrote:
>
> Hi,
>
> On 29/05/2020 07:13:00-0400, Kevin P. Fleming wrote:
> > The driver has a block of RV-1805-specific code (under the comment
> > 'Configure RV1805 specifics'), which is executed before the part
> > autodetection code (under the comment 'part autodetection').
> >
> > If the driver is loaded with the 'generic' device data for abx80x, and
> > the actual part in use is an RV-1805, the part-specific code won't be
> > executed. I'm using this driver in a dynamic Device Tree environment,
> > and at the moment I can't specify the part as the driver is loaded
> > (although I could modify the overlay to support that if required).
> >
> > So the question is: does the RV-1805 specific code *have* to be
> > executed before part autodetection in order to avoid the lockup
> > situation mentioned in the comments, or could it be moved immediately
> > after the autodetection so that it will be always be executed for an
> > RV-1805 part?
>
> You can't detect the difference between the rv1805 and the ab1805 with
> the id registers as both have 0x1805 so you will always have to use the
> correct compatible string for it. The position of the code doesn't
> matter.
>
> Basically, the autodetection should never be used as the device tree
> must describe the actual hardware. My point of view is that this was a
> mistake to have it in the driver in the first place.
>
> --
> Alexandre Belloni, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com