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Subject: Re: [PATCH] i2c: Driver to expose PowerNV platform i2c busses
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Wolfram Sang <wsa@the-dreams.de>
Date: Thu, 13 Nov 2014 23:40:55 +1100
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Cc: Neelesh Gupta <neelegup@linux.vnet.ibm.com>, linuxppc-dev@ozlabs.org,
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On Thu, 2014-11-13 at 21:56 +1100, Benjamin Herrenschmidt wrote:
> 
> No, there is no timeout, if that fails something went quite wrong, it
> could almost be a BUG_ON (basically we passed a wrong token or a NULL
> msg).
> 
> > > +   }
> > > +
> > > +   rc = be64_to_cpu(msg.params[1]);
> > > +   if (rc != OPAL_SUCCESS) {
> > > +           rc = -EIO;
> > > +           goto exit;
> > > +   }
> > > +

Actually, to correct myself, there are a number of error conditions
including timeouts inside the FW layer, but they are returned here, not
from opal_async_wait_response(). So indeed, we could do some error code
conversion at that point.

Neelesh, can you do that on top of your patch that adds the detailed
error codes ? We can merge it fw side tomorrow if you have a new spin,
worst case if the FW is old and only returns OPAL_HARDWARE we return
-EIO and if the FW is newer we'll have more precise error codes in Linux
too.

Cheers,
Ben.