Re: [9fans] Building a Raspberry Pi image / Keyboard support

[erik quanstrom <quanstro@quanstro.net>]

On Sat Jul  5 19:46:36 EDT 2014, anant@kix.in wrote:

> Thanks for the suggestions. The keyboard + mouse work fine with Linux. In
> fact they work on Plan 9 together, but only for a few seconds before I get:
> 
> kb: /dev/usb/ep6.1: read: i/o error
> kb: exiting
> usbotg: ep5.1 error intr 00000082
> usb/kb... kb: exiting

i see these sometimes, too.  a formerly working apple full sized wired keyboard
has stopped working with these errors.  i assume it's something tricky.

however, 9atom has some keyboard/mouse fixes that might be worth checking up
on.  the original version asked for pretty big descriptors from the device, and many
devices generate transaction errors, or otherwise do bad things™ when asked for
a descriptor bigger than they envisioned.  the solution is to ask for the minimum size
descriptor plus enough space to get the descriptor length, then ask again with the
device-provided length.

- erik