Re: [PATCH v5 3/3] iio: magnetometer: add ti tmag5273 driver

From: Andy Shevchenko
Date: Wed Nov 30 2022 - 12:43:16 EST


On Wed, Nov 30, 2022 at 05:32:10PM +0100, Gerald Loacker wrote:
> Am 30.11.2022 um 16:31 schrieb Andy Shevchenko:
> > On Wed, Nov 30, 2022 at 03:53:56PM +0100, Gerald Loacker wrote:

...

> >> + switch (data->devid) {
> >> + case TMAG5273_MANUFACTURER_ID:
> >> + /*
> >> + * The device name matches the orderable part number. 'x' stands
> >> + * for A, B, C or D devices, which have different I2C addresses.
> >> + * Versions 1 or 2 (0 and 3 is reserved) stands for different
> >> + * magnetic strengths.
> >> + */
> >> + snprintf(data->name, sizeof(data->name), "tmag5273x%1u", data->version);
> >> + if (data->version < 1 || data->version > 2)
> >> + dev_warn(data->dev, "Unsupported device %s\n", data->name);
> >> + return 0;
> >> + default:
> >
> >> + dev_warn(data->dev, "Unknown device ID 0x%x\n", data->devid);
> >> + return 0;
> >
> > And we still continue?! Wouldn't be a problem if that ID drastically changed in
> > terms of programming model and may actually be broken by a wrong sequence?
>
> It was suggested by Jonathan to just print a warning instead of
> returning with -ENODEV. Reason was "Often manufacturers spin new
> versions of chips that are compatible enough that we give them a
> fallback compatible in device tree.". For me this makes sense.

Ah, I see. Maybe adding a comment summarizing above?

> >> + }

--
With Best Regards,
Andy Shevchenko