[Linux-stm32] [PATCH V4 21/22] ARM: dts: stm32: Add bindings for USB on AV96

[Manivannan Sadhasivam]

On Fri, Apr 10, 2020 at 11:16:53AM +0200, Marek Vasut wrote:
> On 4/10/20 11:08 AM, Manivannan Sadhasivam wrote:
> > Hi,
> 
> Hi,
> 
> > On Tue, Apr 07, 2020 at 08:37:50PM +0200, Marek Vasut wrote:
> >> On 4/6/20 1:08 PM, Marek Vasut wrote:
> >>> On 4/6/20 9:22 AM, Manivannan Sadhasivam wrote:
> >>>> On Wed, Apr 01, 2020 at 03:22:36PM +0200, Marek Vasut wrote:
> >>>>> Fill in the bindings for USB host and gadget on AV96.
> >>>>>
> >>>>> Signed-off-by: Marek Vasut <marex at denx.de>
> >>>>
> >>>> I can't get the USB B-Micro OTG port to work with this patch. Do I need to
> >>>> enable any configs other than PHY and USB DWC2 drivers?
> >>>
> >>> Only the DWC2 GADGET (and possibly host, for dual-role) and some gadget
> >>> implementation (e.g. gadget zero).
> >>
> >> I think I see what doesn't work for you.
> >>
> >> It seems the following works on next:
> >> power on -> plug in USB stick (or any other USB device) -> unplug ->
> >> plug in usb host (e.g. PC)
> >>
> >> But this does not:
> >> power on -> plug in usb host (e.g. PC)
> >>  - the PC is not detected
> >>
> > 
> > Both doesn't work. I have the rndis gadget configured in userspace but plugging
> > in the micro-b cable doesn't do anything.
> > 
> >> Did that ^ ever work for you before ? I suspect this is a bug in the
> >> DWC2 driver. The OTG operation there is known to be flaky at best.
> > 
> > Not on this board. I don't recall what happended with vendor image. But I do
> > have another STM32MP1 based 96Board (which will be submitted soon), there I can
> > get OTG port working.
> > 
> > But in that board a BG96 modem is connected to USB2 port on the board itself
> > which gets enumerated during probe.
> 
> But it's not configured as OTG on this other board, right ?

It is configured as a OTG port. But that board has a different issue which
resets the board when we connect any OTG cable to act as a host. That's not
related to DWC2 or this issue btw.

Anyway, I can't get OTG (device/host) to work on both old and new boards.

Thanks,
Mani