Messages in this thread | | | From | Linus Walleij <> | Date | Tue, 28 Jun 2022 14:35:30 +0200 | Subject | Re: [PATCH] driver: pca953x: avoid error message when resuming |
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On Mon, Jun 20, 2022 at 6:03 PM Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > On Mon, Jun 20, 2022 at 4:18 PM Pierluigi Passaro > <pierluigi.p@variscite.com> wrote:
> > > > Avoids the error messages "pca953x 1-0020: failed reading register" > > > > when resuming from suspend using gpio-key attached to pca9534. > > > Thanks for your report and fix. My comments below. > > > First of all, how many of them do you get and why is it a problem? > > > > The number of occurrences depends on the time required to I2C bus to fully wake-up. > > It's not a real problem, but the message may lead to think about a real I2C problem. > > Wolfram, do we have any mechanisms that guarantees that I2C traffic is > not going on a semi-woken up host controller? > > Writing this, I'm in doubt this patch is a fix we want. Wouldn't it > just hide the real issue with some resume ordering?
That sounds like a bug in the pm routines in the I2C driver. Why is it returning from [runtime_]resume() if it is not properly resumed?
Yours, Linus Walleij
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