On 29.09.2024 11:46, Jonathan Cameron wrote: > On Thu, 19 Sep 2024 11:19:58 +0200 > Angelo Dureghello <adureghello@xxxxxxxxxxxx> wrote: > > > From: Angelo Dureghello <adureghello@xxxxxxxxxxxx> > > > > Add a new compatible and related bindigns for the fpga-based > > "ad3552r" AXI IP core, a variant of the generic AXI DAC IP. > > > > The AXI "ad3552r" IP is a very similar HDL (fpga) variant of the > > generic AXI "DAC" IP, intended to control ad3552r and similar chips, > > mainly to reach high speed transfer rates using an additional QSPI > > I'd drop the word additional as I assume it is an 'either/or' situation > for the interfaces. > > Do we have other devices using this same IP? I.e. does it make > sense to provide a more generic compatible as a fallback for this one > so that other devices would work without the need for explicit support? > > no, actually ad3552r-axi is only interfacing to ad3552r. I could eventually set adi,axi-dac-9.1.b as a fallback, since it is the "gneric" AXI implementation. > I'd also ideally like a view point from Mark Brown as SPI maintainer > on how we should deal with this highly specialized spi controller. > Is he happy with us using an SPI like binding but not figuring out how > to fit this engine into the SPI subsystem. > > Please +CC Mark and the spi list (done here) on future versions + provide > a clear description of what is going on for them. > Ok. Actually i fixed the bindings for v4 setting axi-ad3552r as an spi-controller, and the target ad3552r as a spi-peripheral (child node). This axi-ad3552r is not only a pure spi-controller since providing some synchronization features not typical of a spi-controller. > Maybe with the binding fixed as spi compliant, we can figure out the > if we eventually want to treat this as an SPI controller from the > kernel driver point of view even if we initially do something 'special'. > > Jonathan > > > > DDR interface. > > > > The ad3552r device is defined as a child of the AXI DAC, that in > > this case is acting as an SPI controller. > > > > Signed-off-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx> > > --- > > .../devicetree/bindings/iio/dac/adi,axi-dac.yaml | 40 ++++++++++++++++++++-- > > 1 file changed, 37 insertions(+), 3 deletions(-) > > > > diff --git a/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml b/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml > > index a55e9bfc66d7..6cf0c2cb84e7 100644 > > --- a/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml > > +++ b/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml > > @@ -19,11 +19,13 @@ description: | > > memory via DMA into the DAC. > > > > https://wiki.analog.com/resources/fpga/docs/axi_dac_ip > > + https://analogdevicesinc.github.io/hdl/library/axi_ad3552r/index.html > > > > properties: > > compatible: > > enum: > > - adi,axi-dac-9.1.b > > + - adi,axi-ad3552r > > > > reg: > > maxItems: 1 > > @@ -41,22 +43,54 @@ properties: > > '#io-backend-cells': > > const: 0 > > > > + '#address-cells': > > + const: 1 > > + > > + '#size-cells': > > + const: 0 > > + > > required: > > - compatible > > - dmas > > - reg > > - clocks > > > > +patternProperties: > > + "^.*@([0-9])$": > > + type: object > > + additionalProperties: true > > + properties: > > + io-backends: > > + description: | > > + AXI backend reference > > + required: > > + - io-backends > > + > > additionalProperties: false > > > > examples: > > - | > > dac@44a00000 { > > - compatible = "adi,axi-dac-9.1.b"; > > - reg = <0x44a00000 0x10000>; > > - dmas = <&tx_dma 0>; > > + compatible = "adi,axi-dac-9.1.b"; > > + reg = <0x44a00000 0x10000>; > > + dmas = <&tx_dma 0>; > > If it makes sense to reformat then separate patch > please as this is hard to read as a result of this > change. Also, as pointed out, be consistent with spacing. > > > + dma-names = "tx"; > > + #io-backend-cells = <0>; > > + clocks = <&axi_clk>; > > + }; > > + > > + - | > > + axi_dac: spi@44a70000 { > > + compatible = "adi,axi-ad3552r"; > > + reg = <0x44a70000 0x1000>; > > + dmas = <&dac_tx_dma 0>; > > dma-names = "tx"; > > #io-backend-cells = <0>; > > clocks = <&axi_clk>; > > + > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + /* DAC devices */ > > }; > > ... > > > -- o/ QW5nZWxvIER1cmVnaGVsbG8= www.kernel-space.org e: angelo at kernel-space.org c: +39 388 8550663
