Re: [PATCH v3 2/4] ACPI / scan: Create platform device for fwnodes with multiple i2c devices

[Hans de Goede]

Hi,

On 07-08-18 13:19, Andy Shevchenko wrote:
> On Tue, 2018-08-07 at 10:05 +0200, Hans de Goede wrote:
> > Some devices have multiple I2cSerialBus resources and for things to
> > work
> > an i2c-client must be instantiated for each, each with its own
> > i2c_device_id.
> >
> > Normally we only instantiate an i2c-client for the first resource,
> > using
> > the ACPI HID as id.
> >
> > This commit adds a list of HIDs of devices, which need multiple i2c-
> > clients
> > instantiated from a single fwnode, to
> > acpi_device_enumeration_by_parent and
> > makes acpi_device_enumeration_by_parent return false for these devices
> > so
> > that a platform device will be instantiated.
> >
> > This allows the drivers/platform/x86/i2c-multi-instantiate.c driver,
> > which
> > knows which i2c_device_id to use for each resource, to bind to the
> > fwnode
> > and initiate an i2c-client for each resource.
>
> > +	/*
> > +	 * These devices have multiple I2cSerialBus resources and an
> > i2c-client
> > +	 * must be instantiated for each, each with its own
> > i2c_device_id.
> > +	 * Normally we only instantiate an i2c-client for the first
> > resource,
> > +	 * using the ACPI HID as id. These special cases are handled by
> > the
> > +	 * drivers/platform/x86/i2c-multi-instantiate.c driver, which
> > knows
> > +	 * which i2c_device_id to use for each resource.
> > +	 */
> > +	static const struct acpi_device_id i2c_multi_instantiate_ids[] =
> > {
> > +		{"BSG1160", 0},
> > +		{"", 0},
> > +	};
>
> Style nits:
> - can we move it outside of function?

Sure, but there are 2 existing users of an array of acpi_device_id-s
combined with an acpi_match_device_ids() call and both have the array
inside the function, so for consistency it seems better to keep it
where it is.

> - terminator better without comma

Agreed, will fix for v4.

> - is this existing style in the file and / or files in this folder for
> IDs? (I mean unnecessary 0:s and empty string?

It seems that all variants one can come up with are already used inside
this single file.

I agree that less is more, so I will change this to:

        static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
                {"BSG1160", },
                {}
        };

For v4.

Regards,

Hans