[PATCH v5 3/5] arm64: dts: rockchip: add rk356x dwc3 usb3 nodes

[Peter Geis]

On Sat, Apr 9, 2022 at 3:37 AM Frank Wunderlich <frank-w at public-files.de> wrote:
>
> Got it,
> these Patches require different clock names
>
> ref_clk => ref
> bus_clk => bus_early
>
> after renaming usb works on my board
>
> will send an follow-up patch for this series
>
> regards Frank
>
>
> > Gesendet: Samstag, 09. April 2022 um 09:23 Uhr
> > Von: "Frank Wunderlich" <frank-w at public-files.de>
> >
> > at least i nailed it down to these 2 commits in drivers/usb/dwc3/core.c, without them it works
> >
> > 5114c3ee2487 2022-01-27 usb: dwc3: Calculate REFCLKPER based on reference clock
> > 33fb697ec7e5 2022-01-27 usb: dwc3: Get clocks individually
>

I've submitted a fix for the dwc3 issue.
https://patchwork.kernel.org/project/linux-rockchip/patch/20220409152116.3834354-1-pgwipeout@gmail.com/
The offending commit was: 33fb697ec7e5 ("usb: dwc3: Get clocks individually").
It breaks backwards compatibility with rk3328, which follows the
rockchip,dwc3.yaml dt-binding, and thus this series as well.

This fix is standalone and necessary no matter which route we decide
to go with this series (and the rk3328/rk3399 support as well).
With this patch, dwc3 is functional on the rk356x as the series was
submitted, so if we decide to fix everything all at once, that is a
viable option.

For those not following the other conversation, here is the TLDR:
- rockchip,dwc3.yaml has different clock names than snps,dwc3.yaml
- rk3328 and rk356x attach directly to the dwc3 core driver
- rk3399 uses the dwc3-simple driver, which still uses the clk_bulk api.
- commit 33fb697ec7e5 changed to individual clocks, which follow
snps,dwc3.yaml naming
- to correct this beyond my fix patch, we would need to align
rockchip,dwc3.yaml with snps,dwc3.yaml, which means rk3328, rk3399,
and rk356x will move to the snps clock naming scheme.

I think we need Rob Herring to weigh in here, as this is a rather
uncomfortable dt-binding issue.