[U-Boot] DWC2 driver issues

Marek Vasut
2015-03-02T11:42:14Z

On Saturday, February 28, 2015 at 05:33:31 AM, Stephen Warren wrote:
> On 02/19/2015 07:29 AM, Marek Vasut wrote:
> > On Monday, February 16, 2015 at 07:28:45 PM, Stephen Warren wrote:
> >> Following on from my Google+ post about DWC2/RPi USB host controller
> >> issues in U-Boot.
>
> ...
>
> >> On an RPi with the DWC2 controller connected directly to a single
> >> external USB connector (i.e model A, A+), a LS (and perhaps FS) device
> >> pluged directly into the board doesn't work due to the small max packet
> >> size limit.
> >>
> >> Your patch 9b1161af8c51 "usb: dwc2: Add support for multi-packet control
> >> xfers" in u-boot-usb.git topic/dwc2 addresses this issue for control
> >> transfers at least. With your patch, I can now enumerate a USB kbd on a
> >> model A+. That's a great improvement; thanks for the quick response with
> >> a patch.
> >>
> >> However, when I enable CONFIG_USB_KEYBOARD, I see errors when the USB
> >>
> >> keyboard input driver initializes:
> >>> starting USB...
> >>> USB0: Core Release: 2.80a
> >>> scanning bus 0 for devices... 3 USB Device(s) found
> >>>
> >>> scanning usb for storage devices... 0 Storage Device(s) found
> >>> scanning usb for ethernet devices... 0 Ethernet Device(s) found
> >>>
> >>> dev = 0df92ac0 pipe = 0x40408380 buf = 0db4a780 size = 8 int = 10
> >>> Failed to get keyboard state from device 413c:2010
> >>
> >> I haven't investigated this further yet.
> >
> > Wow, this error is new, I have not seen this one on SoCFPGA.
>
> This error is because the keyboard driver uses interrupt transfers, and
> these aren't implemented in DWC2.

Uh, the debugging spit in submit_int_msg() should certainly be converted
into something more human readable.

> I worked around this by forcing the
> keyboard driver to use control transfers, and fixing what I think is a
> bug in this case; see patch below. With this, USB keyboard works on an
> RPI A+

Cool, good job.

> although it hangs pretty quickly. I assume one of the busy loops
> in dwc2.c without a time out isn't completing.

Oh, dang. Those should certainly be fixed.

Looking at the patch, could it be that CONFIG_SYS_USB_EVENT_POLL_VIA_CONTROL_EP
support in usb_kbd.c is broken altogether ?