[PATCH master] i2c: imx: increase timeout in i2c_fsl_poll_status from 1 to 5ms

[PATCH master] i2c: imx: increase timeout in i2c_fsl_poll_status from 1 to 5ms

[Ahmad Fatoum]

The current wait time of 1 ms is apparently too short in some
circumstances leading to following error when communicating
with a KSZ switch with 100 kHz from an i.MX8MN I2C controller:

  ERROR: ksz9477-i2c ksz85630: error detecting KSZ9477: I/O error

Increasing the poll time to 5ms resolved this issue:

  ksz9477-i2c ksz85630: Found KSZ9893
  ksz9477-i2c ksz85630: chip id: 0x00989360

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 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 c0af446bcc25..28bd0072addf 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -201,7 +201,7 @@ static int i2c_fsl_trx_complete(struct i2c_adapter *adapter)
 
 static int i2c_fsl_acked(struct i2c_adapter *adapter)
 {
-	return i2c_fsl_poll_status(adapter, 1, 0, I2SR_RXAK);
+	return i2c_fsl_poll_status(adapter, 5, 0, I2SR_RXAK);
 }
 
 static int i2c_fsl_start(struct i2c_adapter *adapter)
-- 
2.30.2

Re: [PATCH master] i2c: imx: increase timeout in i2c_fsl_poll_status from 1 to 5ms

[Sascha Hauer]

On Tue, Jan 10, 2023 at 09:52:37AM +0100, Ahmad Fatoum wrote:
> The current wait time of 1 ms is apparently too short in some
> circumstances leading to following error when communicating
> with a KSZ switch with 100 kHz from an i.MX8MN I2C controller:
> 
>   ERROR: ksz9477-i2c ksz85630: error detecting KSZ9477: I/O error
> 
> Increasing the poll time to 5ms resolved this issue:
> 
>   ksz9477-i2c ksz85630: Found KSZ9893
>   ksz9477-i2c ksz85630: chip id: 0x00989360
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  drivers/i2c/busses/i2c-imx.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Applied, thanks

Sascha

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