i2c-imx: fix error handling

- Return -ETIMEDOUT on bus busy error
- Fix timeout test "time_after(jiffies, orig_jiffies + HZ / 1000)" :
  By default, HZ=100 on arm. This means that this test has no chances to
  work and may result in a dead loop. Set timeout to 500ms.
- Don't try to send a new message if we failed to transmit
  previous one. This was preventing to recover from error on my system
Signed-off-by: NArnaud Patard <apatard@mandriva.com>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

drivers/i2c/busses/i2c-imx.c

@@ -146,10 +146,10 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
 				"<%s> I2C Interrupted\n", __func__);
 			return -EINTR;
 		}
-		if (time_after(jiffies, orig_jiffies + HZ / 1000)) {
+		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 			dev_dbg(&i2c_imx->adapter.dev,
 				"<%s> I2C bus is busy\n", __func__);
-			return -EIO;
+			return -ETIMEDOUT;
 		}
 		schedule();
 	}
@@ -444,6 +444,8 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
 			result = i2c_imx_read(i2c_imx, &msgs[i]);
 		else
 			result = i2c_imx_write(i2c_imx, &msgs[i]);
+		if (result)
+			goto fail0;
 	}
 
 fail0: