Re: [PATCH 2/2] leds: lm3692x: Allow to set ovp and brigthness mode

[Guido Günther]

Hi,
On Sat, Dec 21, 2019 at 08:18:44PM +0100, Pavel Machek wrote:
> Hi!
> 
> > Overvoltage protection and brightness mode are currently hardcoded
> > as disabled in the driver. Make these configurable via DT.
> 
> What exactly is overvoltage protection good for? Should we default to
> 29V if we have no other information?

The OVP protects the IC from overvoltage conditions on the output side.
While looking at the manual again I noticed that i misremembered the
'00' value which means 17V - not unprotected. Also the chip defaults
to 29V OVP so i've adjusted that too.

Cheers,
 -- Guido

> 
> > Signed-off-by: Guido Günther <agx@xxxxxxxxxxx>
> 
> > +	ret = device_property_read_u32(&led->client->dev,
> > +				       "ti,overvoltage-volts", &ovp);
> > +	if (!ret) {
> > +		switch (ovp) {
> > +		case 0:
> > +			break;
> > +		case 22:
> > +			led->boost_ctrl |= LM3692X_OVP_21V;
> > +			break;
> 
> Should be case 21.
> 								Pavel
> -- 
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html