Re: Mainlining Linux Sunxi SoC AW USB

[Petr Vorel <petr.vorel@gmail.com>]

Hi Greg,

[ Cc: linux-sunxi@lists.linux.dev and linux-sunxi@googlegroups.com, which I
should have done before ]

> On Sat, Jul 24, 2021 at 11:54:40AM +0200, Petr Vorel wrote:
> > Hi,

> > I'd like to cleanup and mainline Linux Sunxi SoC AW USB host driver [1].

> Great!

> > What are the most ugly parts which should be replaced? Loading module does not
> > complain about anything?
> > [267044.912155] awusb: loading out-of-tree module taints kernel.

> That will be fixed by moving it into the tree.

> > [267044.912257] awusb: module verification failed: signature and/or required key missing - tainting kernel

> That shows a mis-match between you building a kernel and what keys were
> used to build the distro kernel you are using.

> > [267044.913399] usbcore: registered new interface driver allwinner
> > [267044.913401] awusb: v0.5:AW USB driver

> Looks fine.
Yep, I meant by this, that I see nothing serious (i.e. agree with you).

> > BTW should it go to the host/Kconfig or misc/Kconfig or elsewhere?

> No idea, is this a host driver or does it control a USB device you plug
> into the system?

> > [1] https://github.com/linux-sunxi/sunxi-livesuite/blob/master/awusb/awusb.c

> I looked at this, and it's a device driver, not a host controller
> driver.

> But it looks to need a userspace program for the ioctls, where is that
> code at?  And why does it need any ioctls at all?

> Why is this even a driver at all, it looks like you can write a small
> userspace program using libusb to do everything it does, right?  What
> exactly is this driver needed for?

I'm sorry for not providing more info at the beginning. This is a driver for
host computer (i.e. developers laptop) used by LiveSuit tool [2] to flash Images
to the NAND of Allwinner devices. LiveSuit itself [3] is unfortunately provided
only in binary form. The only open source code with GPL v2 license is awusb
driver. Thus I thought I could ease my life with upstreaming at least the
kernel driver. But maybe it's not a good idea. I'm using LiveSuit for flashing
Allwinner A31, but it requires quite old distro due libqtgui4. Maybe sunxi folks
use something newer nowadays, but I haven't found anything in their wiki.

Kind regards,
Petr

[2] https://github.com/linux-sunxi/sunxi-livesuite
[3] https://github.com/linux-sunxi/sunxi-livesuite/tree/master/x86-64

> thanks,

> greg k-h