Re: [PATCH 4.4 16/37] i2c: rcar: rework hw init

Ben Hutchings
2018-06-18T18:46:39Z

On Tue, 2018-06-05 at 19:01 +0200, Greg Kroah-Hartman wrote:
> 4.4-stable review patch.  If anyone has any objections, please let me know.
>
> ------------------
>
> From: Wolfram Sang <wsa+renesas@sang-engineering.com>
>
> commit 2c78cdc1c06308a59d6ed4145cdba73fdeff8c0d upstream.
>
> We don't need to init HW before every transfer since we know the HW
> state then. HW init at probe time is enough.

This part got reverted upstream by:

commit ae481cc139658e89eb3ea671dd00b67bd87f01a3
Author: Wolfram Sang <wsa+renesas@sang-engineering.com>
Date:   Tue Apr 18 20:38:35 2017 +0200

i2c: rcar: fix resume by always initializing registers before transfer

so maybe that should go into stable (4.4 and 4.9 branches) too?

Ben.

> While here, add setting the
> clock register which belongs to init HW. Also, set MDBS bit since not
> setting it is prohibited according to the manual.
[...]

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