On Wed, Jan 13, 2021 at 6:30 PM André Przywara [off-list ref] wrote:

On 06/01/2021 15:56, Chen-Yu Tsai wrote:

quoted

Hi,

On Wed, Jan 6, 2021 at 11:05 PM Andre Przywara [off-list ref] wrote:

quoted

In recent Allwinner SoCs the first USB host controller (HCI0) shares
the first PHY with the MUSB controller. Probably to make this sharing
work, we were avoiding to declare this in the DT. This has two
shortcomings:
- U-Boot (which uses the same .dts) cannot use this port in host mode
  without a PHY linked, so we were loosing one USB port there.
- It requires the MUSB driver to be enabled and loaded, although we
  don't actually use it.

To avoid those issues, let's add this PHY link to the A64 and H6 .dtsi
files. After all PHY port 0 *is* connected to HCI0, so we should describe
it as this. Remove the part from the boards which were already doing
that.

This makes it work in U-Boot, also improves compatiblity when no MUSB
driver is loaded (for instance in distribution installers).

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
 arch/arm64/boot/dts/allwinner/sun50i-a64-pinebook.dts | 4 ----
 arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi         | 4 ++++
 arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi          | 4 ++++

It would be better if the H6 parts were separated out.

Sure.

quoted

Please also add a fixes tag, which helps with backporting.

The whole concept of DT backports raises some eyebrows here, but it's
surely easy enough to do.

Well, whether people choose to backport is their decision. But providing
information used to decide whether to do so, and if yes, what else is
needed, is IMHO something the author can help with.

Likely backport scenarios are distribution kernels AFAICT.

ChenYu

Thanks,
Andre.