RE: [EXT] I2C_IMX support for i.MX8MP

Shenwei Wang
2022-08-18T11:59:44Z

Hi Richard,

Nothing is hidden here. That is PAD control register, and should be documented in the IOMUXC and PIN Control section in the RM.

Regards,
Shenwei

> -----Original Message-----
> From: Richard Leitner <richard.leitner@linux.dev>
> Sent: Thursday, August 18, 2022 3:41 AM
> To: Shenwei Wang <shenwei.wang@nxp.com>
> Cc: imx@lists.linux.dev
> Subject: Re: [EXT] I2C_IMX support for i.MX8MP
>
> Caution: EXT Email
>
> On Wed, Aug 17, 2022 at 02:14:53PM +0000, Shenwei Wang wrote:
> >
> > The support for imx8mp-evk board has already pushed to mainline. That
> includes the usage of i2c-imx.
> > For example, a GPIO expander is connected to I2C3 on evk board.
>
> Thanks again. It now works with linux v6.0-rc1.
>
> The missing piece was setting the 0x40000000 bit in the SW_PAD_CTL registers
> of SCL and SDA.
> Unfortunately this bit seems to be undocumented in the RefManual and also the
> driver documentation doesn't state anything about it.
>
> Can you please shed some light in this "magic" bit? Would be really helpful,
> thanks!
>
> Furthermore I guess documenting it somewhere in the driver or setting it
> implicitely (if that's possible) would be a good idea?
>
> regards;rl