Re: [PATCH v1 6/8] iio: dac: ds4424: clear outputs on probe

[Oleksij Rempel <o.rempel@pengutronix.de>]

On Fri, Jan 23, 2026 at 09:38:04AM +0000, Jonathan Cameron wrote:
> On Mon, 19 Jan 2026 19:24:22 +0100
> Oleksij Rempel <o.rempel@pengutronix.de> wrote:
> 
> > The DS44xx devices have no reset pin or reset bit, so output registers
> > may retain preconfigured values across reboot or warm reset.
> > 
> > Also, the driver suspend/resume path restores from data->raw. When the
> > device is first probed, data->raw is zero-initialized and may not match
> > the actual hardware state. A later suspend/resume can therefore change an
> > output from a preconfigured non-zero value to 0 mA.
> 
> For DACs we often want to retain settings from before kernel load (or
> on exit of the driver).  Can we just read them back from the device to
> fill in the cached versions?  If we can I think that would be preferred
> option.

ACK, i was not sure what is the best way here.

Best Regards,
Oleksij
-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |