Re: [PATCH v3 1/3] dt-bindings: dmaengine: Document qcom,gpi dma binding

[Vinod Koul <vkoul@kernel.org>]

Hi Rob,

On 29-09-20, 13:44, Rob Herring wrote:

> > +description: |
> > +  QCOM GPI DMA controller provides DMA capabilities for
> > +  peripheral buses such as I2C, UART, and SPI.
> > +
> > +allOf:
> > +  - $ref: "dma-controller.yaml#"
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - qcom,gpi-dma
> 
> Should be SoC specific.

Okay, will add

> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    description:
> > +      Interrupt lines for each GPII instance
> 
> GPII or GPI?

Hw uses GPII as "GPI Instance" :) so will update this

> > +    maxItems: 13
> > +
> > +  "#dma-cells":
> > +    const: 3
> > +    description: >
> > +      DMA clients must use the format described in dma.txt, giving a phandle
> > +      to the DMA controller plus the following 3 integer cells:
> > +      - channel: if set to 0xffffffff, any available channel will be allocated
> > +        for the client. Otherwise, the exact channel specified will be used.
> > +      - seid: serial id of the client as defined in the SoC documentation.
> > +      - client: type of the client as defined in dt-bindings/dma/qcom-gpi.h
> > +
> > +  iommus:
> > +    maxItems: 1
> > +
> > +  dma-channels:
> > +    maxItems: 1
> 
> Not an array. Is there a maximum number of channels or 2^32 is valid?

I have not seen any max limit put, but we can be assured that it will
not go to 2^32, we can put a reasonable limit ..

Will add maximum :)

> > +
> > +  dma-channel-mask:
> > +    maxItems: 1
> 
> So up to 32 channels?

yep!

-- 
~Vinod