Re: [PATCH v5] i2c: imx: make bus recovery through pinctrl optional

From: Leo Li
Date: Mon Sep 12 2016 - 12:35:50 EST


On Wed, Sep 7, 2016 at 5:07 AM, Tracy Smith <tlsmith3777@xxxxxxxxx> wrote:
> Hello, bus recovery is needed generally speaking because of potential
> protocol errors that might cause a failure condition hanging the bus.
>
> It happens frequently during bring-up of new I2C devices because firmware in
> I2C controllers fail to handle properly protocol errors.
>
> Can NXP add bus recovery for the LS1021A and LS1043A in a separate patch--
> unless there is no HW bus recovery mechanism?
>
> The concern is while fixing I.MX, NXP will fail to fix the driver bus
> recovery for the LS1021A and LS1043A and the bus will hang.
>
> If bus recovery is supported on the LS1021A and the LS1043A, a patch should
> be provided or added in this patch instead of simply disabling bus recovery.
> Request NXP to consider the patch if there is HW support for bus recovery.

FYI. http://patchwork.ozlabs.org/patch/573879/ This seem to be the
patch you are asking for. I have asked the original developer to
update the patch according to Wolfram's comment and work together with
the current pinctrl/gpio based recovery. In the meanwhile you can
make use of the patch for now for LS1021A and LS1043A if necessary.

Regards,
Leo