On Tue, Apr 16, 2019 at 2:19 AM Maxime Ripard <maxime.ripard@xxxxxxxxxxx> wrote: > > Hi Rob, > > On Mon, Apr 15, 2019 at 08:36:28PM -0500, Rob Herring wrote: > > On Mon, Apr 15, 2019 at 7:07 AM Maxime Ripard <maxime.ripard@xxxxxxxxxxx> wrote: > > > > > > Not all controllers using the A31 SPDIF binding actually have some RX > > > capabilities, and therefore on some controllers we don't have the option to > > > set an RX DMA channel. > > > > > > This was already done in the DTSI, but the binding itself was never > > > updated. > > > > > > Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx> > > > --- > > > Documentation/devicetree/bindings/sound/allwinner,sun6i-a31-spdif.yaml | 16 +++++++++++++--- > > > 1 file changed, 13 insertions(+), 3 deletions(-) > > > > > > diff --git a/Documentation/devicetree/bindings/sound/allwinner,sun6i-a31-spdif.yaml b/Documentation/devicetree/bindings/sound/allwinner,sun6i-a31-spdif.yaml > > > index 7329d9fcf34c..800f794fafe0 100644 > > > --- a/Documentation/devicetree/bindings/sound/allwinner,sun6i-a31-spdif.yaml > > > +++ b/Documentation/devicetree/bindings/sound/allwinner,sun6i-a31-spdif.yaml > > > @@ -44,14 +44,24 @@ properties: > > > - const: spdif > > > > > > dmas: > > > + minItems: 1 > > > + maxItems: 2 > > > items: > > > - description: RX DMA Channel > > > - description: TX DMA Channel > > > + description: > > > + Some controllers cannot receive but can only transmit data. In > > > + such a case, the RX DMA channel is to be omitted. > > > > Really, the schema is saying rx is optional, but it doesn't really > > matter here as the schema for each item is just 'description'. > > What should I do here then? > > Remove the global description and leave only the one under items? I think the opposite. Just drop 'items' and leave 'description'. > Also, it won't necessarily match the dma-names (since rx might be > there or not), does it matter or is it obvious enough that we don't > care? > > > > dma-names: > > > - items: > > > - - const: rx > > > - - const: tx > > > + minItems: 1 > > > + maxItems: 2 > > > + enum: > > > + - rx > > > + - tx > > > + description: > > > + Some controllers cannot receive but can only transmit data. In > > > + such a case, the RX name is to be omitted. > > > > Here it matters though. This would allow just 'tx', '"tx", "tx"', or > > either order. > > > > You need something like this: > > > > oneOf: > > - items: > > - const: rx > > - const: tx > > - const: tx > > Ok. > > > Ideally, we'd always put the required entry first and avoid this > > problem. Not always possible if the first entry gets removed in later > > h/w. > > One of the question I was wondering myself when I wrote those schemas > is how are we supposed to deal with lists that need to have a > particular set of values, but without any particular order? 'items' can be a list or dictionary. When it's a dictionary, the schema for 'items' is applied to each item. For example: items: enum: [ rx, tx ] uniqueItems: true 'uniqueItems' prevents the case of 'rx, rx' or 'tx, tx'. > rx and tx here is a good example of that. We need both (let's leave > the "missing RX" case aside for a minute), but since we reference them > by name, '"rx", "tx"' is strictly equivalent to '"tx", "rx"'. Yet, > items cares about the order, so the latter would fail to validate with > that schemas. Even when we reference things by name, the order should be defined still. Using names allows for skipping entries. If you have a mixture, I'd prefer to see dts files cleaned-up. Rob
