Re: [PATCH 1/3] i2c: mxs: always end a transfer with a proper STOP

[Lucas Stach <l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>]

Am Montag, den 08.04.2013, 19:21 +0200 schrieb Wolfram Sang:
> On Thu, Mar 14, 2013 at 12:49:08PM +0100, Lucas Stach wrote:
> > Our transfers always start with the device address, so there is never a
> > situation where we just do a restart transfer. Full blown transfers should
> > always end with a STOP as per i2c spec.
> 
> ? I don't get the description. Does "restart transfer" mean repeated
> start? What has the device address to do with it?
> 

A restart transfer is when you just repeat the START condition, without
putting the device address on the bus again.

In the MXS driver we put the device address on the bus for every
transaction we get handed in from the i2c core, so there is never a
situation where we just repeat the start condition without sending out
the device address. Before this patch we would not match every
transaction, but only the last in the list of pending ones, with a STOP
condition, which is a violation of the spec.

If there are no other comments, I'll send out a V2 today, to take in
Marek's remarks.
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