> On 14. 4. 2022, at 17:43, Rob Herring <robh@xxxxxxxxxx> wrote: > > 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). Ha! <-1> didn’t work for me but <(-1)> does. > >> >> 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. Then I may send some patch to that end. >> >> .../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. That’s why. Fixed length it is then. > > This needs some description about there being 1 of 4 outputs being > connected. OK. Description there will be. >> + >> +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 >> >> Martin
