Re: [PATCH 1/3] hwmon: spd5118: Do not fail resume on temporary I2C errors

[Guenter Roeck]

On 1/10/26 14:27, Armin Wolf wrote:
> Am 10.01.26 um 18:19 schrieb Tinsae Tadesse:
>
> > SPD5118 DDR5 temperature sensors may be temporarily unavailable
> > during s2idle resume. Ignore temporary -ENXIO and -EIO errors during resume and allow
> > register synchronization to be retried later.
>
> Hi,
>
> do you know if the error is caused by the SPD5118 device itself or by the underlying
> i2c controller? Please also share the output of "acpidump" and the name of the i2c
> controller used to communicate with the SPD5118.
>
> > Signed-off-by: Tinsae Tadesse <tinsaetadesse2015@xxxxxxxxx>
> > ---
> >   drivers/hwmon/spd5118.c | 8 +++++++-
> >   1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/hwmon/spd5118.c b/drivers/hwmon/spd5118.c
> > index 5da44571b6a0..ec9f14f6e0df 100644
> > --- a/drivers/hwmon/spd5118.c
> > +++ b/drivers/hwmon/spd5118.c
> > @@ -512,9 +512,15 @@ static int spd5118_resume(struct device *dev)
> >   {
> >       struct spd5118_data *data = dev_get_drvdata(dev);
> >       struct regmap *regmap = data->regmap;
> > +    int ret;
> >       regcache_cache_only(regmap, false);
> > -    return regcache_sync(regmap);
> > +    ret = regcache_sync(regmap);
> > +    if(ret == -ENXIO || ret == -EIO) {
> > +        dev_warn(dev, "SPD hub not responding on resume (%d), deferring init\n", ret);
> > +        return 0;
> > +    }
>
> The specification says that the SPD5118 might take up to 10ms to initialize its i2c interface
> after power on. Can you test if simply waiting for 10ms before syncing the regcache solves this
> issue?

It seems to be highly unlikely that this code executes within 10ms of powering on the memory.

Guenter

> Thanks,
> Armin Wolf
>
> > +    return ret;
> >   }
> >   static DEFINE_SIMPLE_DEV_PM_OPS(spd5118_pm_ops, spd5118_suspend, spd5118_resume);