Re: [PATCH 1/2] dt-bindings: GPIO: Add generic serializer binding

[Geert Uytterhoeven <geert@linux-m68k.org>]

On Mon, Dec 14, 2015 at 5:41 PM, Andrew F. Davis <afd@ti.com> wrote:
> What I'm worried about looks to have happened with the gpio-74x164
> driver, this is kind of the companion device to mine (74164 / 74165)
> and should work with any 74164 compatible shift register (possibly 100s
> of versions of them), but the compatible string that was added is
> "fairchild,74hc595", a relatively new device by a single manufacturer.

In hindsight, that probably should have been "motorola,mc74hc595" instead.
Recently I read that Motorola invented the 74hc59x for their "new" SPI bus
as that time, as the 74164 is not 100% SPI-compatible.

Given the limitations of the '164 for SPI, is the same true for '165, and
should it be "[...]74[...]597" instead?

> The problem this has is then that boards will use this compatible string
> even if the parts are not actually the Fairchild version, just to get
> the match, when they should be using a generic string.

They're all supposed to be "compatible".
Personally, I wouldn't object to just "74595", cfr. "ns16550a".

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds