[PATCH] i2c: designware: Don't mask TX_EMPTY if write is in progress
From: Jisheng Zhang
Date: Fri Oct 30 2015 - 03:42:28 EST
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
@@ -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;
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