Re: [PATCH v3 2/2] ALSA: hda/tas2781: Add tas2781 HDA driver

From: Andy Shevchenko
Date: Fri Aug 18 2023 - 13:02:32 EST


On Fri, Aug 18, 2023 at 11:00:34AM -0500, Pierre-Louis Bossart wrote:

...

> > +static int comp_match_tas2781_dev_name(struct device *dev,
> > + void *data)
> > +{
> > + struct scodec_dev_name *p = data;
> > + const char *d = dev_name(dev);
> > + int n = strlen(p->bus);
> > + char tmp[32];
> > +
> > + /* check the bus name */
> > + if (strncmp(d, p->bus, n))
> > + return 0;

> > + /* skip the bus number */
> > + if (isdigit(d[n]))
> > + n++;

Why do you think it can't be two or more digits?

> > + /* the rest must be exact matching */
> > + snprintf(tmp, sizeof(tmp), "-%s:00", p->hid);
>
> ACPI can sometimes add :01 suffixes, this looks like the re-invention of
> an ACPI helper?
>
> Adding Andy for the ACPI review.
>
> > + return !strcmp(d + n, tmp);
> > +}

Yes, this looks like reinventing a wheel.
Just compare dev_name() against what is in p->....

...

> > +static void tas2781_fixup_i2c(struct hda_codec *cdc,
> > + const struct hda_fixup *fix, int action)
> > +{
> > + tas2781_generic_fixup(cdc, action, "i2c", "TIAS2781");
>
> TI ACPI ID is TXNW
>
> https://uefi.org/ACPI_ID_List?search=TEXAS
>
> There's also a PNP ID PXN
>
> https://uefi.org/PNP_ID_List?search=TEXAS
>
> "TIAS" looks like an invented identifier. It's not uncommon but should
> be recorded with a comment if I am not mistaken.
>
> > +}

Thank you, but actually it's a strong NAK to this even with the comment.
We have to teach people to follow the specification (may be even hard way).

So where did you get the ill-formed ACPI ID?
Is Texas Instrument aware of this?
Can we have a confirmation letter from TI for this ID, please?

--
With Best Regards,
Andy Shevchenko