On Mon, 17 Dec 2018 at 23:40, Rob Herring <robh@xxxxxxxxxx> wrote: > > On Wed, Dec 12, 2018 at 12:16:42PM +0100, Krzysztof Kozlowski wrote: > > Document new linux,trigger-pattern property for initialization of LED > > pattern trigger. > > > > Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx> > > --- > > Documentation/devicetree/bindings/leds/common.txt | 36 +++++++++++++++++++++++ > > 1 file changed, 36 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/leds/common.txt b/Documentation/devicetree/bindings/leds/common.txt > > index aa1399814a2a..3daccd4ea8a3 100644 > > --- a/Documentation/devicetree/bindings/leds/common.txt > > +++ b/Documentation/devicetree/bindings/leds/common.txt > > @@ -37,6 +37,42 @@ Optional properties for child nodes: > > "ide-disk" - LED indicates IDE disk activity (deprecated), > > in new implementations use "disk-activity" > > "timer" - LED flashes at a fixed, configurable rate > > + "pattern" - LED alters the brightness for the specified duration with one > > + software timer (requires "led-pattern" property) > > + > > +- led-pattern : String with default pattern for certain triggers. Each trigger > > + may parse this string differently: > > + - one-shot : two numbers specifying delay on and delay off, > > + - timer : two numbers specifying delay on and delay off, > > I misunderstood that these triggers applied to this. Is there any point > to supporting these modes? I am not sure whether I explained this clearly enough, so let me be more specific. The "led-pattern" is a string with pattern which will be interpreted differently, based on LED trigger. One-shot and timer triggers expect two numbers. Pattern trigger expects full pattern. > Aren't they just a subset or simplification > of a pattern? Yes, they are. > > Can we control the timer frequency from DT? The pattern could address > that limitation. No, currently we cannot. This patch with pattern solves that issue. > > > + - pattern : The pattern is given by a series of tuples, of > > Don't you need one-shot vs. repeat modes for patterns too? Repeat mode is defined by trigger. One-shot is one time. Timer and patter triggers are repeating. > > I could imagine you'd want a pattern for any trigger. In general I think that only these three triggers require such initialization through pattern. Other triggers - like heartbeat or activity - have they own bindings (or do not need any). Following Pavel's suggestion, I could convert it to array of integers which still should be suitable for these and any future triggers operating on numbers. Best regards, Krzysztof
