From 69151e532c97f983b498ea03e20b1598a5487318 Mon Sep 17 00:00:00 2001
From: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Date: Fri, 6 Nov 2009 21:51:00 +0900
Subject: [PATCH] i2c-designware: Disable TX_EMPTY when all i2c_msg msgs has
been processed
Currently we disable TX_EMPTY interrupt when buf_len is zero, but this
is wrong. (buf_len == 0) means that all transmit data in the current
i2c_msg message has been sent out, but that doesn't necessarily mean
all i2c_msg messages have been processed.
TX_EMPTY interrupt is used as the driving force of DW I2C transactions,
so we need to keep it enabled as long as i2c_msg messages are available.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
---
drivers/i2c/busses/i2c-designware.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-designware.c b/drivers/i2c/busses/i2c-designware.c
index f184d822d3d4..6acbe846e9c6 100644
--- a/drivers/i2c/busses/i2c-designware.c
+++ b/drivers/i2c/busses/i2c-designware.c
@@ -415,12 +415,17 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
/* more bytes to be written */
dev->status |= STATUS_WRITE_IN_PROGRESS;
break;
- } else {
+ } else
dev->status &= ~STATUS_WRITE_IN_PROGRESS;
- intr_mask &= ~DW_IC_INTR_TX_EMPTY;
- }
}
+ /*
+ * If i2c_msg index search is completed, we don't need TX_EMPTY
+ * interrupt any more.
+ */
+ if (dev->msg_write_idx == dev->msgs_num)
+ intr_mask &= ~DW_IC_INTR_TX_EMPTY;
+
writel(intr_mask, dev->base + DW_IC_INTR_MASK);
}
--
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