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

Stefan Eichenberger
2026-02-18T15:09:54Z

From: Stefan Eichenberger <stefan.eichenberger@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@0x00 0x02 r1 w1@0x00 0x02 r1
Error: Sending messages failed: Connection timed out

Fixes: 5f5c2d4579ca ("i2c: imx: prevent rescheduling in non dma mode")
Cc: <stable@vger.kernel.org> # v6.13+
Signed-off-by: Stefan Eichenberger <stefan.eichenberger@toradex.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