The i2c layer can report a variety of errors, including -ENXIO for an i2c NAK. Instead of treating them all as -EIO, pass the actual i2c layer error up to the caller. However, still report as -EIO the unlikely case that a transaction was partially completed, and no error message was returned from i2c_*(). Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx> --- drivers/input/touchscreen/atmel_mxt_ts.c | 28 ++++++++++++++++++++-------- 1 files changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c index 25d3dd5..3672553 100644 --- a/drivers/input/touchscreen/atmel_mxt_ts.c +++ b/drivers/input/touchscreen/atmel_mxt_ts.c @@ -396,6 +396,7 @@ static int __mxt_read_reg(struct i2c_client *client, { struct i2c_msg xfer[2]; u8 buf[2]; + int ret; buf[0] = reg & 0xff; buf[1] = (reg >> 8) & 0xff; @@ -412,12 +413,17 @@ static int __mxt_read_reg(struct i2c_client *client, xfer[1].len = len; xfer[1].buf = val; - if (i2c_transfer(client->adapter, xfer, 2) != 2) { - dev_err(&client->dev, "%s: i2c transfer failed\n", __func__); - return -EIO; + ret = i2c_transfer(client->adapter, xfer, 2); + if (ret == 2) { + ret = 0; + } else { + if (ret >= 0) + ret = -EIO; + dev_err(&client->dev, "%s: i2c transfer failed (%d)\n", + __func__, ret); } - return 0; + return ret; } static int mxt_read_reg(struct i2c_client *client, u16 reg, u8 *val) @@ -428,17 +434,23 @@ static int mxt_read_reg(struct i2c_client *client, u16 reg, u8 *val) static int mxt_write_reg(struct i2c_client *client, u16 reg, u8 val) { u8 buf[3]; + int ret; buf[0] = reg & 0xff; buf[1] = (reg >> 8) & 0xff; buf[2] = val; - if (i2c_master_send(client, buf, 3) != 3) { - dev_err(&client->dev, "%s: i2c send failed\n", __func__); - return -EIO; + ret = i2c_master_send(client, buf, 3); + if (ret == 3) { + ret = 0; + } else { + if (ret >= 0) + ret = -EIO; + dev_err(&client->dev, "%s: i2c send failed (%d)\n", + __func__, ret); } - return 0; + return ret; } static int mxt_read_object_table(struct i2c_client *client, -- 1.7.7.3 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html