[PATCH v1] i2c: imx: Retry transfer on transient failure

[Francesco Dolcini]

From: Oleksandr Suvorov <oleksandr.suvorov at toradex.com>

Set the i2c_adapter retries field to a sensible value. This allows
the i2c core to retry master_xfer()/master_xfer_atomic() when it
returns -EAGAIN. Currently the i2c-imx driver returns -EAGAIN only
on Tx arbitration failure (I2SR_IAL).

Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov at toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini at toradex.com>
---
 drivers/i2c/busses/i2c-imx.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index e9e2db68b9fb..26738e713c94 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -54,6 +54,7 @@
 #define DRIVER_NAME "imx-i2c"
 
 #define I2C_IMX_CHECK_DELAY 30000 /* Time to check for bus idle, in NS */
+#define I2C_IMX_MAX_RETRIES 3     /* Retries on arbitration loss */
 
 /*
  * Enable DMA if transfer byte size is bigger than this threshold.
@@ -1477,6 +1478,7 @@ static int i2c_imx_probe(struct platform_device *pdev)
 	i2c_imx->adapter.dev.parent	= &pdev->dev;
 	i2c_imx->adapter.nr		= pdev->id;
 	i2c_imx->adapter.dev.of_node	= pdev->dev.of_node;
+	i2c_imx->adapter.retries	= I2C_IMX_MAX_RETRIES;
 	i2c_imx->base			= base;
 	ACPI_COMPANION_SET(&i2c_imx->adapter.dev, ACPI_COMPANION(&pdev->dev));
 
-- 
2.25.1