[PATCH v2] i2c: i2c-cros-ec-tunnel: Reduce logging noise

From: Guenter Roeck
Date: Mon Jul 25 2016 - 16:59:17 EST

If an i2c access through i2c-cros-ec-tunnel returns an error, the following
log message is seen on the console.

cros-ec-i2c-tunnel ff200000.spi:ec@0:i2c-tunnel:
Error parsing EC i2c message -121

This can happen a lot if, for example, the i2c-detect command is executed.

Since it is perfectly normal for an i2c controller to report an error,
drop the message. Also, report -ENXIO instead of -EREMOTEIO if the access
error is due to NAK from the device, and return -EIO instead of -EREMOTEIO
for unknown errors, as suggested in Documentation/i2c/fault-codes.

Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
v2: Drop message entirely instead of replacing it with dev_dbg,
and return -EIO instead of -EREMOTEIO for unknown errors.

drivers/i2c/busses/i2c-cros-ec-tunnel.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-cros-ec-tunnel.c b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
index a0d95ff682ae..7b9b2ff97d77 100644
--- a/drivers/i2c/busses/i2c-cros-ec-tunnel.c
+++ b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
@@ -154,8 +154,10 @@ static int ec_i2c_parse_response(const u8 *buf, struct i2c_msg i2c_msgs[],
resp = (const struct ec_response_i2c_passthru *)buf;
if (resp->i2c_status & EC_I2C_STATUS_TIMEOUT)
return -ETIMEDOUT;
- else if (resp->i2c_status & EC_I2C_STATUS_ERROR)
- return -EREMOTEIO;
+ else if (resp->i2c_status & EC_I2C_STATUS_NAK)
+ return -ENXIO;
+ else if (resp->i2c_status)
+ return -EIO;

/* Other side could send us back fewer messages, but not more */
if (resp->num_msgs > *num)
@@ -222,10 +224,8 @@ static int ec_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg i2c_msgs[],

result = ec_i2c_parse_response(msg->data, i2c_msgs, &num);
- if (result < 0) {
- dev_err(dev, "Error parsing EC i2c message %d\n", result);
+ if (result < 0)
goto exit;
- }

/* Indicate success by saying how many messages were sent */
result = num;