Re: [PATCH v2 1/2] gpio: pca953x: fix handling of automatic address incrementing

Uwe Kleine-König
2020-04-14T10:16:03Z

Hello,

obviously I failed to Cc: the gpio maintainers. Should I resend because
of that?

On Tue, Mar 31, 2020 at 01:07:59PM +0300, Andy Shevchenko wrote:
> On Mon, Mar 30, 2020 at 09:50:17PM +0200, Uwe Kleine-König wrote:
>
> ...
>
> > The history of this bug is a bit complicated. Commit b32cecb46bdc
> > ("gpio: pca953x: Extract the register address mangling to single
> > function") changed which chips and functions are affected. Commit
> > 3b00691cc46a ("gpio: pca953x: hack to fix 24 bit gpio expanders") used
> > some duct tape to make the driver at least appear to work. Commit
> > 49427232764d ("gpio: pca953x: Perform basic regmap conversion")
> > introduced the caching. Commit b4818afeacbd ("gpio: pca953x: Add
> > set_multiple to allow multiple bits to be set in one write.") introduced
> > the .set_multiple() callback which didn't work for chips that need the
> > AI bit which was fixed later for some chips in 8958262af3fb ("gpio:
> > pca953x: Repair multi-byte IO address increment on PCA9575"). So I'm
> > sorry, I don't know which commit I should pick for a Fixes: line.
>
> It's allowed to put more, but I rather utilize Depends-on for that.
>
> So, something like
>
> Fixes: b4818afeacbd ...
> Depends-on: 8958262af3fb ...

I don't know what is best here. Using

Fixes: b4818afeacbd ("gpio: pca953x: Add set_multiple to allow multiple bits to be set in one write.")

seems sensible. Not sure which commits are sensible to list in
Depends-on lines. I tend to just don't list any and then backport on
request of the stable maintainers iff and when application to older
versions failed.

Linus/Bartosz: Do you care for application of the tags according to your
taste?

Best regards
Uwe

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