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

Stefan Eichenberger eichest at gmail.com
Tue Mar 3 01:14:08 PST 2026


Hi Frank,

On Wed, Feb 18, 2026 at 05:37:54PM +0100, Stefan Eichenberger wrote:
> 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 at 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".

Have you had a chance to look at the waveform? Do you have any concerns
about the proposed solution?

Best regards,
Stefan



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