Re: [PATCH v2 1/4] i2c: imx: only poll for bus busy in multi master mode

Hi Fabio, Stefan,

On Wed, Aug 21, 2024 at 08:01:20AM -0300, Fabio Estevam wrote:

Hi Stefan,

On Mon, Aug 19, 2024 at 4:20 AM Stefan Eichenberger [off-list ref] wrote:

quoted

From: Stefan Eichenberger <redacted>

According to the i.MX8M Mini reference manual chapter "16.1.4.2
Generation of Start" it is only necessary to poll for bus busy and
arbitration lost in multi master mode. This helps to avoid rescheduling
while the i2c bus is busy and avoids SMBus devices to timeout.

Signed-off-by: Stefan Eichenberger <redacted>
Reviewed-by: Frank Li <Frank.Li@nxp.com>

This fixes a pca953x probe error on an imx8mp board running linux-stable 6.6:

[    1.893260] pca953x 2-0020: failed writing register
[    1.898258] pca953x 2-0020: probe with driver pca953x failed with error -11

Could you please add a Fixes tag and Cc stable so that this can reach
the stable kernels?

Tested-by: Fabio Estevam <redacted>

Thanks a lot,

It looks like with this patch, the I2SR_IAL interrupt is not cleared.
I would expect some kind of interrupt storm. Can you confirm it?

Regards,
Oleksij
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