Re: [PATCH] iio: dac: ad5593r: Dynamically set AD5593R channel modes

[Andy Shevchenko]

On Wed, Sep 2, 2020 at 11:09 AM Hennerich, Michael
<Michael.Hennerich@xxxxxxxxxx> wrote:
> > From: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> > Sent: Montag, 31. August 2020 14:46
> > On Mon, Aug 31, 2020 at 2:28 PM AceLan Kao <acelan.kao@xxxxxxxxxxxxx>
> > wrote:

...

> > P.S. Jonathan, it seems this driver has artificial ACPI HID. We probably have to
> > remove it. However, ADS is indeed reserved for Analog Devices in PNP registry.
> > Can we have AD's official answer on this?
> > Cc'ing additional AD people.
>
> Agreed, this ID was chosen under the PNP ID Vendor Space for Analog Devices Inc.
> Days back, I did a quick kernel grep, and there are many drivers which use the 3-letter
> PNP ID as acpi_device_id. So, I thought this being not an issue.

No, no, the use of PNP ID is not an issue. The point is if the ID is
artificial or official.

> I'm against removing it since I know people shipping this in their ACPI tables already.

I see. Can we consider this email as the official answer from AD that
this ID is being allocated for this certain component?

> Regarding ACPI DSD customization, one way to do this is to move this into the BIOS.
> This way the particular piece of HW can be customized rather than manage HW
> connections in software.

Assuming the confirmation on the above, indeed, one may use ACPI HID
with DSD properties in the firmware. Main purpose of PRP0001 is the
*development* stage of the product at which a vendor should take care
about allocation of proper ACPI IDs for the components in use. Yes, I
know that this is not always feasible b/c some HW component vendors
don't care about ACPI at all.

-- 
With Best Regards,
Andy Shevchenko