Re: [PATCH 1/6] arm64: xilinx: Do not use '_' in DT node names

From: Laurent Pinchart
Date: Tue Sep 19 2023 - 03:56:39 EST


On Tue, Sep 19, 2023 at 09:47:52AM +0200, Michal Simek wrote:
>
>
> On 9/18/23 16:56, Laurent Pinchart wrote:
> > Hi Michal,
> >
> > Thank you for the patch.
> >
> > On Mon, Sep 18, 2023 at 02:41:12PM +0200, Michal Simek wrote:
> >> Character '_' not recommended in node name. Use '-' instead.
> >> Pretty much run seds below for node names.
> >> s/zynqmp_ipi/zynqmp-ipi/
> >> s/nvmem_firmware/nvmem-firmware/
> >> s/soc_revision/soc-revision/
> >> s/si5335_/si5335-/
> >>
> >> Signed-off-by: Michal Simek <michal.simek@xxxxxxx>
> >
> > The si5335 nodes may be better named after the clock name instead of the
> > component type, but that's nitpicking.
>
> I don't know what's the guidance on this. fixed-clock.yaml is using generic
> "clock" name. I have no problem to do it if this is recommended way to go.
>
>
> >> ---
> >>
> >> arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts | 4 ++--
> >> arch/arm64/boot/dts/xilinx/zynqmp.dtsi | 6 +++---
> >> 2 files changed, 5 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts b/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts
> >> index d0091d3cb764..52f998c22538 100644
> >> --- a/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts
> >> +++ b/arch/arm64/boot/dts/xilinx/zynqmp-zcu100-revC.dts
> >> @@ -123,13 +123,13 @@ ina226 {
> >> io-channels = <&u35 0>, <&u35 1>, <&u35 2>, <&u35 3>;
> >> };
> >>
> >> - si5335_0: si5335_0 { /* clk0_usb - u23 */
> >> + si5335_0: si5335-0 { /* clk0_usb - u23 */
> >> compatible = "fixed-clock";
> >> #clock-cells = <0>;
> >> clock-frequency = <26000000>;
> >> };
> >>
> >> - si5335_1: si5335_1 { /* clk1_dp - u23 */
> >> + si5335_1: si5335-1 { /* clk1_dp - u23 */
> >> compatible = "fixed-clock";
> >> #clock-cells = <0>;
> >> clock-frequency = <27000000>;
> >> diff --git a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> >> index b61fc99cd911..e50e95cbe817 100644
> >> --- a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> >> +++ b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> >> @@ -129,7 +129,7 @@ rproc_1_fw_image: memory@3ef00000 {
> >> };
> >> };
> >>
> >> - zynqmp_ipi: zynqmp_ipi {
> >> + zynqmp_ipi: zynqmp-ipi {
> >> bootph-all;
> >> compatible = "xlnx,zynqmp-ipi-mailbox";
> >> interrupt-parent = <&gic>;
> >> @@ -194,12 +194,12 @@ zynqmp_power: zynqmp-power {
> >> mbox-names = "tx", "rx";
> >> };
> >>
> >> - nvmem_firmware {
> >> + nvmem-firmware {
> >> compatible = "xlnx,zynqmp-nvmem-fw";
> >> #address-cells = <1>;
> >> #size-cells = <1>;
> >>
> >> - soc_revision: soc_revision@0 {
> >> + soc_revision: soc-revision@0 {
> >
> > Unless I'm mistaken, this will change the userspace API, as it changes
> > the nvmem cell name. Is it an issue ?
>
> Based on
> https://docs.kernel.org/driver-api/nvmem.html#userspace-binary-interface
>
> The only interface to user space is via nvmem file which has all of them
> together. And reference to this node is the same if used inside kernel itself.
> That's why I think there is no change in connection to user space API from nvmem
> side. Of course entry is listed differently if you parse DT names.

Ah my bad. It should be fine then, as long as nobody in the kernel calls
nvmem_cell_get("soc_revision"), which I didn't find any occurrence of.

--
Regards,

Laurent Pinchart