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>

diff --git a/drivers/i2c/busses/i2c-designware.c b/drivers/i2c/busses/i2c-designware.c
index cdfd94e41ccc9b2b278b1fd410756be86e1c5c57..bfb42f0f87a617f02fcd6fe1713a730793e43948 100644 (file)
--- a/drivers/i2c/busses/i2c-designware.c
+++ b/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--;
                }
+
+               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;
        }
 
-       intr_mask = DW_IC_INTR_STOP_DET | DW_IC_INTR_TX_ABRT;
-       if (buf_len > 0) { /* more bytes to be written */
-               intr_mask |= DW_IC_INTR_TX_EMPTY;
-               dev->status |= STATUS_WRITE_IN_PROGRESS;
-       } else
-               dev->status &= ~STATUS_WRITE_IN_PROGRESS;
        writel(intr_mask, dev->base + DW_IC_INTR_MASK);
-
-       dev->tx_buf_len = buf_len;
 }
 
 static void