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>

1 files changed, 12 insertions, 8 deletions

diff --git a/drivers/i2c/busses/i2c-designware.c b/drivers/i2c/busses/i2c-designware.c
index cdfd94e41cc..bfb42f0f87a 100644
--- 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