Re: [PATCH-v5 RESEND 2/5] i2c: pxa: enable/disable i2c module across msg xfer

From	Wolfram Sang <wsa@the-dreams.de>
Newsgroups	linux.kernel
Subject	Re: [PATCH-v5 RESEND 2/5] i2c: pxa: enable/disable i2c module across msg xfer
Date	2015-09-11 21:00 +0200
Message-ID	<q7BId-1Oi-3@gated-at.bofh.it> (permalink)
References	<q0T7c-7Da-11@gated-at.bofh.it> <q0T7c-7Da-15@gated-at.bofh.it>
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On Mon, Aug 24, 2015 at 11:29:35AM +0530, Vaibhav Hiremath wrote:
> From: Yi Zhang <yizhang@marvell.com>
> 
> Enable i2c module/unit before transmission and disable when it
> finishes.
> 
> why?
> It's because the i2c bus may be disturbed if the slave device,
> typically a touch, powers on.

I am not convinced, "may disturb" is too weak for me. It would need a
way more detailed description of the problem which makes clear that
this mechanism is the only way to go forward.

Can't you use Runtime PM for that?

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Re: [PATCH-v5 RESEND 2/5] i2c: pxa: enable/disable i2c module across  msg xfer Wolfram Sang <wsa@the-dreams.de> - 2015-09-11 21:00 +0200
  Re: [PATCH-v5 RESEND 2/5] i2c: pxa: enable/disable i2c module across  msg xfer Vaibhav Hiremath <vaibhav.hiremath@linaro.org> - 2015-09-14 07:10 +0200

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