Re: [PATCH v1 2/2] i2c: imx: ensure no clock is generated after last read

Stefan Eichenberger
2026-02-18T16:37:58Z

Hi Frank,

On Wed, Feb 18, 2026 at 11:26:52AM -0500, Frank Li wrote:
> On Wed, Feb 18, 2026 at 04:08:50PM +0100, Stefan Eichenberger wrote:
> > From: Stefan Eichenberger <stefan.eichenberger@toradex.com>
> >
> > When reading from the I2DR register, right after releasing the bus by
> > clearing MSTA and MTX, the I2C controller might still generate an
> > additional clock cycle which can cause devices to misbehave. Ensure to
>
> Do you means SCL have additional toggle? You capture waveform?
>

Yes exactly. We were able to capture the waveform when the issue
happens. It doesn't always happen though, it depends on how much time
passes between clearing MSTA and MTX and reading from I2DR.

If you want to see the waveform, I uploaded it to our server:
https://share.toradex.com/dwnhcrl6b9toib6
You can see the additional clock at the right end, after "0x17 + NAK".

Regards,
Stefan