Re: [PATCH 1/2] dt: bindings: lp5024: Introduce the lp5024 and lp5018 RGB driver

[Jacek Anaszewski]

On 1/8/19 9:53 PM, Dan Murphy wrote:
> Jacek
>
> On 1/8/19 2:33 PM, Jacek Anaszewski wrote:
> > Dan,
> >
> > On 12/19/18 5:26 PM, Dan Murphy wrote:
> > > Introduce the bindings for the Texas Instruments LP5024 and the LP5018
> > > RGB LED device driver. The LP5024/18 can control RGB LEDs individually
> > > or as part of a control bank group. These devices have the ability
> > > to adjust the mixing control for the RGB LEDs to obtain different colors
> > > independent of the overall brightness of the LED grouping.
> > >
> > > Datasheet:
> > > http://www.ti.com/lit/ds/symlink/lp5024.pdf
> > >
> > > Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
> > > ---
> > >   .../devicetree/bindings/leds/leds-lp5024.txt | 63 +++++++++++++++++++
> > >  Â 1 file changed, 63 insertions(+)
> > >  Â create mode 100644 Documentation/devicetree/bindings/leds/leds-lp5024.txt
> > >
> > > diff --git a/Documentation/devicetree/bindings/leds/leds-lp5024.txt b/Documentation/devicetree/bindings/leds/leds-lp5024.txt
> > > new file mode 100644
> > > index 000000000000..9567aa6f7813
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/leds/leds-lp5024.txt
> > > @@ -0,0 +1,63 @@
> > > +* Texas Instruments - LP5024/18 RGB LED driver
> > > +
> > > +The LM3692x is an ultra-compact, highly efficient,
> > > +white-LED driver designed for LCD display backlighting.
> > > +
> > > +The main difference between the LP5024 and L5018 is the number of
> > > +RGB LEDs they support. The LP5024 supports twenty four strings while the
> > > +LP5018 supports eighteen strings.
> > > +
> > > +Required properties:
> > > +ÂÂÂ - compatible:
> > > +ÂÂÂÂÂÂÂ "ti,lp5018"
> > > +ÂÂÂÂÂÂÂ "ti,lp5024"
> > > +ÂÂÂ - reg :Â I2C slave address
> > > +ÂÂÂ - #address-cells : 1
> > > +ÂÂÂ - #size-cells : 0
> > > +
> > > +Optional properties:
> > > +ÂÂÂ - enable-gpios : gpio pin to enable/disable the device.
> > > +ÂÂÂ - vled-supply : LED supply
> > > +
> > > +Required child properties:
> > > +ÂÂÂ - reg : Is the child node iteration.
> > > +ÂÂÂ - led-sources : LP5024 - 0 - 7
> > > +ÂÂÂÂÂÂÂÂÂÂÂ LP5018 - 0 - 5
> > > +ÂÂÂÂÂÂÂÂÂÂÂ Declares the LED string or strings that the child node
> > > + will control. If ti,control-bank is set then this
> > > +ÂÂÂÂÂÂÂÂÂÂÂ property will contain multiple LED IDs.
> > > +
> > > +Optional child properties:
> > > +ÂÂÂ - label : see Documentation/devicetree/bindings/leds/common.txt
> > > +ÂÂÂ - linux,default-trigger :
> > > +ÂÂÂÂÂÂ see Documentation/devicetree/bindings/leds/common.txt
> > > +ÂÂÂ - ti,control-bank : Indicates that the LED strings declared in the
> > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ led-sources property are grouped within a control
> > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ bank for brightness and mixing control.
> > > +
> > > +Example:
> > > +
> > > +led-controller@28 {
> > > +ÂÂÂ compatible = "ti,lp5024";
> > > +ÂÂÂ reg = <0x28>;
> > > +ÂÂÂ #address-cells = <1>;
> > > +ÂÂÂ #size-cells = <0>;
> > > +
> > > +ÂÂÂ enable-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
> > > +ÂÂÂ vled-supply = <&vbatt>;
> > > +
> > > +ÂÂÂ led@0 {
> > > +ÂÂÂÂÂÂÂ reg = <0>;
> > > +ÂÂÂÂÂÂÂ led-sources = <1>;
> > > +ÂÂÂ };
> > > +
> > > +ÂÂÂ led@1 {
> > > +ÂÂÂÂÂÂÂ reg = <1>;
> > > +ÂÂÂÂÂÂÂ led-sources = <0 6>;
> > > +ÂÂÂÂÂÂÂ ti,control-bank;
> >
> > Do you really need ti,control-bank? Doesn't led-sources array size
> > greater than 1 mean that the node describes control bank?
>
> That will work too.

> > Also, does it make sense to have only two LEDs in the bank?
>
> The array can populate all 7 LEDs in a single node.  I only show 2 here as the example.
> See the description above of the led-sources

OK, I confused RGB LED modules with banks.

Shouldn't we allow for defining either strings or RGB LED
triplets somehow then?

--
Best regards,
Jacek Anaszewski