i2c-designware: i2c_dw_xfer_msg: Fix i2c_msg search bug

In case a work-in-progress i2c_msg has more bytes to be written, we
need to set STATUS_WRITE_IN_PROGRESS and exit from the msg_write_idx-
searching loop.  Otherwise, we will overtake the current msg_write_idx
without waiting for its transmission to be processed.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

drivers/i2c/busses/i2c-designware.c

@@ -338,6 +338,8 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 	u32 addr = msgs[dev->msg_write_idx].addr;
 	u32 buf_len = dev->tx_buf_len;
 
+	intr_mask = DW_IC_INTR_STOP_DET | DW_IC_INTR_TX_ABRT;
+
 	if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) {
 		/* Disable the adapter */
 		writel(0, dev->base + DW_IC_ENABLE);
@@ -387,17 +389,19 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 						dev->base + DW_IC_DATA_CMD);
 			tx_limit--; buf_len--;
 		}
-	}
 
-	intr_mask = DW_IC_INTR_STOP_DET | DW_IC_INTR_TX_ABRT;
-	if (buf_len > 0) { /* more bytes to be written */
+		dev->tx_buf_len = buf_len;
+
+		if (buf_len > 0) {
+			/* more bytes to be written */
 			intr_mask |= DW_IC_INTR_TX_EMPTY;
 			dev->status |= STATUS_WRITE_IN_PROGRESS;
+			break;
 		} else
 			dev->status &= ~STATUS_WRITE_IN_PROGRESS;
-	writel(intr_mask, dev->base + DW_IC_INTR_MASK);
+	}
 
-	dev->tx_buf_len = buf_len;
+	writel(intr_mask, dev->base + DW_IC_INTR_MASK);
 }
 
 static void