[PATCH] i2c: designware: Don't mask TX_EMPTY if write is in progress

[Jisheng Zhang]

Currently when i2c_msg index search is completed, TX_EMPTY interrupt
will be masked. But if the size of i2c_msg data is longer than the size
of the tx buffer, we still need TX_EMPTY interrupt, otherwise we will
get "controller timed out" error.

This patch fixes this issue by only masking TX_EMPTY if i2c_msg index
search is completed and write is not in progress.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
---
 drivers/i2c/busses/i2c-designware-core.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 7441cdc..a2eb212 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -542,10 +542,11 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
 	}
 
 	/*
-	 * If i2c_msg index search is completed, we don't need TX_EMPTY
-	 * interrupt any more.
+	 * If i2c_msg index search is completed and writing is not in progress,
+	 * we don't need TX_EMPTY interrupt any more.
 	 */
-	if (dev->msg_write_idx == dev->msgs_num)
+	if (dev->msg_write_idx == dev->msgs_num &&
+			!(dev->status & STATUS_WRITE_IN_PROGRESS))
 		intr_mask &= ~DW_IC_INTR_TX_EMPTY;
 
 	if (dev->msg_err)
-- 
2.6.2

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