Re: [PATCH] ASoC: cs35l56: Support clock stop mode 1 if enabled in ACPI

[Richard Fitzgerald]

On 11/03/2026 3:30 pm, Mark Brown wrote:
> On Wed, Mar 11, 2026 at 03:17:16PM +0000, Richard Fitzgerald wrote:
> > On 11/03/2026 3:03 pm, Mark Brown wrote:
> > > On Wed, Mar 11, 2026 at 02:21:53PM +0000, Richard Fitzgerald wrote:
>
> > > > +	ret = fwnode_property_read_u8(dev_fwnode(cs35l56->base.dev),
> > > > +				      "mipi-sdw-clock-stop-mode1-supported",
> > > > +				      &clock_stop_1);
> > > > +	if (ret == 0)
> > > > +		prop->clk_stop_mode1 = !!clock_stop_1;
>
> > > Should this be using fwnode_property_read_bool()?
>
> > No, that only reports whether the property exists (it calls
> > acpi_fwnode_property_present()).
>
> > The property can (and usually does) exist with value 0 to disable
> > clock-stop-mode1.
>
> > I copied the use of fwnode_property_read_u8() to read this property from
> > the implementation of sdw_slave_read_prop().
>
> Hrm, OK - the property seems to be confusingly named and defined :(  Can
> it have any values other than 0 and 1?

It's part of the SoundWire spec. We have to follow it.

The current spec says:

mipi-sdw-clock-stop-mode1-supported
This optional Boolean Property shall indicate whether or not Clock-stop
is supported on this Device.
Integer (Boolean)
Values:
False (zero): Clock-stop mode1 is not supported on this Device.
True (nonzero): Clock-stop mode1 is supported on this Device.