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

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Date:	Wed, 05 Aug 2015 18:12:09 +0530
From:	Vaibhav Hiremath <vaibhav.hiremath@...aro.org>
To:	Shubhrajyoti Datta <shubhrajyoti.datta@...il.com>
CC:	linux-arm-kernel@...ts.infradead.org, devicetree@...r.kernel.org,
	Wolfram Sang <wsa@...-dreams.de>,
	Yi Zhang <yizhang@...vell.com>, linux-kernel@...r.kernel.org,
	linux-i2c@...r.kernel.org, robert.jarzmik@...e.fr
Subject: Re: [PATCH-v5 2/5] i2c: pxa: enable/disable i2c module across msg
 xfer



On Wednesday 05 August 2015 04:16 PM, Shubhrajyoti Datta wrote:
> hi ,
> On Tue, Jul 21, 2015 at 6:11 PM, Vaibhav Hiremath
> <vaibhav.hiremath@...aro.org> wrote:
>> From: Yi Zhang <yizhang@...vell.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.
>
> Why should that be an issue?
> Is it an errata.
>

Not I am aware of.

> In which mode it is an issue slave / master or both?
>

since it talks about touch, I expect it to be master mode.

Thanks,
Vaibhav
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