Re: [PATCH 10/13 v4] drm/i915/intel_i2c: always wait for IDLE before clearing NAK

From: Chris Wilson
Date: Tue Mar 27 2012 - 15:18:16 EST


On Wed, 28 Mar 2012 02:36:19 +0800, Daniel Kurtz <djkurtz@xxxxxxxxxxxx> wrote:
> The GMBUS controller can report a NAK condition while a transaction is
> still active. If the driver is fast enough, and the bus is slow enough,
> the driver may clear the NAK condition while the controller is still
> busy, resulting in a confused GMBUS controller. This will leave the
> controller in a bad state such that the next transaction may fail.
>
> Also, return -ENXIO if a device NAKs a transaction.
>
> Note: this patch also refactors gmbus_xfer to remove the "done" label.
>
> Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>

Thanks for clarifying the appropriate return codes.

Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
-Chris

--
Chris Wilson, Intel Open Source Technology Centre
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