[PATCH 12/12] i2c: pxa: enable/disable i2c module across msg xfer
yizhang at mx0b-0016f401.pphosted.com
Wed Jun 3 03:56:26 PDT 2015
On Tue, Jun 02, 2015 at 10:29:23PM +0530, Vaibhav Hiremath wrote:
> On Tuesday 02 June 2015 10:22 PM, Vaibhav Hiremath wrote:
> >On Thursday 28 May 2015 06:53 PM, Russell King - ARM Linux wrote:
> >>On Thu, May 28, 2015 at 06:33:44PM +0530, Vaibhav Hiremath wrote:
> >>>From: Yi Zhang <yizhang at marvell.com>
> >>>Enable i2c module/unit before transmission and disable when it finishes.
> >>>It's because the i2c bus may be distrubed if the slave device,
> >>>typically a touch, powers on.
> >>I'd recommend that this is a DT property - not every platform is going to
> >>want this, and as there is rudimentary I2C slave support in this driver,
> >>this change breaks that.
> >I would take it as two different comments here, and I believe you also
> >meant same,
> >1. Not breaking I2C slave support
> >Not sure whether enabling/disabling module in ISR would suffice here.
> >To be specific, in the functions i2c_pxa_slave_start() &
> Please ignore this option, as enable is important to generate interrupt
> on slave start.
Yes, you are right, enabling i2c controller first is must for
generating the interrupt
> I will add DT property with clear note on SLAVE support issue, so that
> it can be disabled and SLAVE support should work as is.
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