Input: atmel_mxt_ts - return errors from i2c layer
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@chromium.org>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index ee37b0b..a68b227 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -396,6 +396,7 @@
{
struct i2c_msg xfer[2];
u8 buf[2];
+ int ret;
buf[0] = reg & 0xff;
buf[1] = (reg >> 8) & 0xff;
@@ -412,12 +413,17 @@
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_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,