[PATCH v1 1/2] i2c: imx: fix i2c issue when reading multiple messages

Frank Li Frank.li at nxp.com
Wed Feb 18 08:22:44 PST 2026


On Wed, Feb 18, 2026 at 04:08:49PM +0100, Stefan Eichenberger wrote:
> From: Stefan Eichenberger <stefan.eichenberger at toradex.com>
>
> When reading multiple messages, meaning a repeated start is required,
> polling the bus busy bit must be avoided. This must only be done for
> the last message. Otherwise, the driver will timeout.
>
> Here an example of such a sequence that fails with an error:
> i2ctransfer -y -a 0 w1 at 0x00 0x02 r1 w1 at 0x00 0x02 r1
> Error: Sending messages failed: Connection timed out
>
> Fixes: 5f5c2d4579ca ("i2c: imx: prevent rescheduling in non dma mode")
> Cc: <stable at vger.kernel.org> # v6.13+
> Signed-off-by: Stefan Eichenberger <stefan.eichenberger at toradex.com>
> ---
Reviewed-by: Frank Li <Frank.Li at nxp.com>
>  drivers/i2c/busses/i2c-imx.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index 85f554044cf1e..56e2a14495a9a 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -1522,7 +1522,7 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs,
>  		dev_err(&i2c_imx->adapter.dev, "<%s> read timedout\n", __func__);
>  		return -ETIMEDOUT;
>  	}
> -	if (!i2c_imx->stopped)
> +	if (i2c_imx->is_lastmsg && !i2c_imx->stopped)
>  		return i2c_imx_bus_busy(i2c_imx, 0, false);
>
>  	return 0;
> --
> 2.51.0
>



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