linux-kernel - Re: [PATCH-v3 02/11] i2c: pxa: No need to set slave addr for i2c master mode reset

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Date:	Fri, 10 Jul 2015 16:56:29 +0200
From:	Wolfram Sang <wsa@...-dreams.de>
To:	Vaibhav Hiremath <vaibhav.hiremath@...aro.org>
Cc:	linux-i2c@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	robert.jarzmik@...e.fr, devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org, robh+dt@...nel.org,
	"Jett.Zhou" <jtzhou@...vell.com>
Subject: Re: [PATCH-v3 02/11] i2c: pxa: No need to set slave addr for i2c
 master mode reset

On Fri, Jul 10, 2015 at 07:55:31PM +0530, Vaibhav Hiremath wrote:
> 
> 
> On Friday 10 July 2015 07:44 PM, Wolfram Sang wrote:
> >On Fri, Jul 10, 2015 at 06:08:43PM +0530, Vaibhav Hiremath wrote:
> >>
> >>
> >>On Friday 10 July 2015 01:41 PM, Wolfram Sang wrote:
> >>>On Tue, Jul 07, 2015 at 12:54:46AM +0530, Vaibhav Hiremath wrote:
> >>>>Normally i2c controller works as master, so slave addr is not needed, or it
> >>>>will impact some slave device (eg. ST NFC chip) i2c accesses, because it has
> >>>>the same i2c address with controller.
> >>>
> >>>Just to make sure: Does it? As I read the code, slave interrupts are
> >>>enabled later only when slave mode is selected? Is that a HW bug? And if
> >>>so, can't the code just be moved into this #ifdef block later?
> >>>
> >>
> >>Yes we could, infact I thought about it;
> >>but I would break recommended sequence here.
> >
> >And did you set the "own slave address" to a value which one of your
> >existing i2c slaves also has (without enabling slave mode)? Did it
> >disturb communication?
> >
> 
> Since slave and master mode are mutual exclusive,
> I did not try this.

Ehrm, what I meant was. Did you see the issue mentioned in the above
commit message? Can you reproduce it? You don't need to enable slave
mode for that, no?


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