-----Original Message-----
From: [email protected] [mailto:[email protected]] 
On Behalf Of Shinya Kuribayashi
Sent: Monday, October 12, 2009 9:54 PM
To: [email protected]; [email protected]
Cc: [email protected]; [email protected]; 
[email protected]
Subject: [PATCH 14/16] i2c-designware: Deferred FIFO-data-counting variables 
initialization

As the driver and hardware always process the given data in parallel, it would 
be better to initialize those {tx,rx}_limit or rx_valid variables just prior to 
be used.

This will help to send/receive data as much as possible.

Signed-off-by: Shinya Kuribayashi <[email protected]>
---
 drivers/i2c/busses/i2c-designware.c |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware.c 
b/drivers/i2c/busses/i2c-designware.c
index b3152c2..f7ea032 100644
--- a/drivers/i2c/busses/i2c-designware.c
+++ b/drivers/i2c/busses/i2c-designware.c
@@ -359,8 +359,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)  {
        struct i2c_msg *msgs = dev->msgs;
        u32 intr_mask;
-       int tx_limit = dev->tx_fifo_depth - readl(dev->base + DW_IC_TXFLR);
-       int rx_limit = dev->rx_fifo_depth - readl(dev->base + DW_IC_RXFLR);
+       int tx_limit, rx_limit;
        u32 addr = msgs[dev->msg_write_idx].addr;
        u32 buf_len = dev->tx_buf_len;
        u8 *buf = dev->tx_buf;;
@@ -386,6 +385,9 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
                        buf_len = msgs[dev->msg_write_idx].len;
                }
 
+               tx_limit = dev->tx_fifo_depth - readl(dev->base + DW_IC_TXFLR);
+               rx_limit = dev->rx_fifo_depth - readl(dev->base + DW_IC_RXFLR);
+
                while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) {
                        if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
                                writel(0x100, dev->base + DW_IC_DATA_CMD); @@ 
-418,7 +420,7 @@ i2c_dw_read(struct dw_i2c_dev *dev)  {
        struct i2c_msg *msgs = dev->msgs;
        u32 addr = msgs[dev->msg_read_idx].addr;
-       int rx_valid = readl(dev->base + DW_IC_RXFLR);
+       int rx_valid;
 
        for (; dev->msg_read_idx < dev->msgs_num; dev->msg_read_idx++) {
                u32 len;
@@ -439,6 +441,8 @@ i2c_dw_read(struct dw_i2c_dev *dev)
                        buf = dev->rx_buf;
                }
 
+               rx_valid = readl(dev->base + DW_IC_RXFLR);
+
                for (; len > 0 && rx_valid > 0; len--, rx_valid--)
                        *buf++ = readl(dev->base + DW_IC_DATA_CMD);
 
--
1.6.5

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