Issuing the following commands doesn't succeed:
- conn
- disconn
- conn
This USB driver doesn't even disconnect without this patch.
If the USB driver has been started from another hart, closing it
will not disable the PLIC interrupt. This means it's possible many
harts get the USB interrupt and thus make the USB look very unstable.
Fix these problems by disconnecting the USB via the USB_POWER
register at shutdown and disabling the interrupt at shutdown. Also
clear the software internals via the mpfs_sw_setup() for the conn /
disconect loop to succeed.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
5cedf1ef2a