MOXA I/O errors on 2.6.28+

[Jan Kasprzak <kas@fi.muni.cz>]

	Hello,

I have several servers with MOXA C320 serial boards. Starting with 2.6.28,
some ports on MOXA boards sometimes get to a state where open("/dev/ttyMX<n>")
returns -EIO. I use the servers with MOXA boards as serial console hubs,
and I think the EIO state is caused by the remote getty or the whole remote
server being restarted.

	After getting EIO, this particular port always returns EIO, until
the server is rebooted. The moxa module usage count is non-zero (even when
nobody has the board open), so reloading just the moxa.ko module is not
possible.

	2.6.27 is OK, 2.6.28 and 2.6.29-rc8 is faulty. I can git bisect
if you want (I have a spare server which I can reboot at will).

	My MOXA boards are

01:08.0 Serial controller: Moxa Technologies Co Ltd Intellio C320 Turbo PCI (rev 02)

	What can I do to have this problem fixed? Thanks,

-Yenya

-- 
| Jan "Yenya" Kasprzak  <kas at {fi.muni.cz - work | yenya.net - private}> |
| GPG: ID 1024/D3498839      Fingerprint 0D99A7FB206605D7 8B35FCDE05B18A5E |
| http://www.fi.muni.cz/~kas/    Journal: http://www.fi.muni.cz/~kas/blog/ |
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