ARM: mvebu: Enable XHCI on the Armada 385 AP

Hi Andrew,

Quoted 30 lines · Andrew Lunn

Quoted 19 lines · Maxime Ripard

Hi all,

This serie enables the Armada 385 AP XHCI controller.

Since the controller uses a GPIO-controlled VBUS, we used the phy-generic driver, and made the needed additions to the xhci-plat driver to retrieve a USB phy.

Unfortunately, some glitches were also found along the way, mostly because of the probe deferring that was introduced by this phy retrieval.

Since the introduction of the Armada 38x support in 3.16, the driver was attempting to write into registers while the clock wasn't enabled yet. This was working because the bootloader left it enabled, but in the case of a deferred probing, the clock would have been disabled by the error path of our driver, and this would fail. This should go in 3.19, and any stable kernel for 3.16+.

Quoted 3 lines

The two patches remaining are "regular" patches, and are aimed at 3.20. The last patch depend on my previous serie to introduce support for the the A385 AP board.

Hi Maxime

I assume you want me to take 3/3? Any other route is not simple, since this file only exists in mvebu/dt and maybe a staging branch of arm-soc.

Quoted 1 line

What route do you think the other patches will take?

There should be no merge dependency, but merging the third patch alone will probably result on a boot breakage. I don't think it really matters though, since this is a new board, so I guess it can go through the USB-PHY tree.