On Tue, Apr 12, 2022 at 12:22:03AM +0200, Martin Povišer wrote: > Apple's Audio DMA Controller (ADMAC) is used to fetch and store audio > samples on SoCs from the "Apple Silicon" family. > > Signed-off-by: Martin Povišer <povik+lin@xxxxxxxxxxx> > --- > > After the v1 discussion, I dropped the apple,internal-irq-destination > property and instead the index of the usable interrupt is now signified > by prepending -1 entries to the interrupts= list. This works when I do > it like this: > > interrupt-parent = <&aic>; > interrupts = <AIC_IRQ 0xffffffff 0>, > <AIC_IRQ 626 IRQ_TYPE_LEVEL_HIGH>; BTW, just use '-1'. dtc takes negative values (and other expressions). > > I would find it neat to do it like this: > > interrupts-extended = <0xffffffff>, > <&aic AIC_IRQ 626 IRQ_TYPE_LEVEL_HIGH>; > > but unfortunately the kernel doesn't pick up on it: > > [ 0.767964] apple-admac 238200000.dma-controller: error -6: IRQ index 0 not found > [ 0.773943] apple-admac 238200000.dma-controller: error -6: IRQ index 1 not found > [ 0.780154] apple-admac 238200000.dma-controller: error -6: IRQ index 2 not found > [ 0.786367] apple-admac 238200000.dma-controller: error -6: IRQ index 3 not found > [ 0.788592] apple-admac 238200000.dma-controller: error -6: no usable interrupt We should make this case work. It is less fragile IMO as it doesn't depend on the provider's translation of cells. > > .../devicetree/bindings/dma/apple,admac.yaml | 68 +++++++++++++++++++ > 1 file changed, 68 insertions(+) > create mode 100644 Documentation/devicetree/bindings/dma/apple,admac.yaml > > diff --git a/Documentation/devicetree/bindings/dma/apple,admac.yaml b/Documentation/devicetree/bindings/dma/apple,admac.yaml > new file mode 100644 > index 000000000000..bbd5eaf5f709 > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/apple,admac.yaml > @@ -0,0 +1,68 @@ > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/dma/apple,admac.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Apple Audio DMA Controller (ADMAC) > + > +description: | > + Apple's Audio DMA Controller (ADMAC) is used to fetch and store audio samples > + on SoCs from the "Apple Silicon" family. > + > + The controller has been seen with up to 24 channels. Even-numbered channels > + are TX-only, odd-numbered are RX-only. Individual channels are coupled to > + fixed device endpoints. > + > +maintainers: > + - Martin Povišer <povik+lin@xxxxxxxxxxx> > + > +allOf: > + - $ref: "dma-controller.yaml#" > + > +properties: > + compatible: > + items: > + - enum: > + - apple,t6000-admac > + - apple,t8103-admac > + - const: apple,admac > + > + reg: > + maxItems: 1 > + > + '#dma-cells': > + const: 1 > + description: > + Clients specify single cell with channel number. > + > + dma-channels: > + maximum: 24 > + > + interrupts: > + minItems: 1 > + maxItems: 4 I'm now confused why this is variable. Put -1 entries on the end if that's why it is variable. This needs some description about there being 1 of 4 outputs being connected. > + > +required: > + - compatible > + - reg > + - '#dma-cells' > + - dma-channels > + - interrupts > + > +additionalProperties: false > + > +examples: > + - | > + #include <dt-bindings/interrupt-controller/apple-aic.h> > + #include <dt-bindings/interrupt-controller/irq.h> > + > + admac: dma-controller@238200000 { > + compatible = "apple,t8103-admac", "apple,admac"; > + reg = <0x38200000 0x34000>; > + dma-channels = <24>; > + interrupt-parent = <&aic>; > + interrupts = <AIC_IRQ 0xffffffff 0>, > + <AIC_IRQ 626 IRQ_TYPE_LEVEL_HIGH>; > + #dma-cells = <1>; > + }; > -- > 2.33.0 > >
