Re: [PATCH] sh: sh7785lcr: register the PCA9564 as I2C bus 0

[Geert Uytterhoeven]

Hi Karl,

On Sat, 3 Oct 2026 at 11:51, Karl Mehltretter <kmehltretter@xxxxxxxxx> wrote:
> On Sat, Oct 03, 2026 at 11:38:43AM +0100, John Paul Adrian Glaubitz wrote:
> > > Reviewed-by: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
> >
> > I have to admit though I don't fully understand the description of this
> > patch. Either I don't have enough coffee or it's not precise enough.
>
> Thanks for testing and reviewing! I agree the changelog doesn't explain
> why -1 is wrong and 0 is right for this board very clearly. I'll give it
> a day or so to step back and submit a v2 with your tags and a better
> changelog.

Perhaps something like:

Before commit 44454baa7ca7bb57 ("i2c: Dynamically assign adapter id if
it wasn't explictly specified"), a negative ID was replaced by zero,
and I2C bus zero was instantiated.  Since that commit, a negative ID
is passed verbatim, instantiating an I2C bus with a dynamic number.
As SH boards still use i2c_register_board_info(0, ...) to register I2C
devices, they rely on the I2C bus being bus zero, causing registration to fail.

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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