On OMAP4 OMAP_I2C_STAT_NACK is causing a timeout on the next access.
The isr cleans all flags in OMAP_I2C_CON_REG by setting OMAP_I2C_CON_STP
OMAP_I2C_CON_STP is also set in omap_i2c_xfer_msg on the last message.

According to the TI TSR the sequence for OMAP_I2C_STAT_NACK and
OMAP_I2C_STAT_AL are nearly the same.
Removing the OMAP_I2C_CON_STP part in the isr fix the problem.
Tested on OMAP4430 and OMAP3530 (here NACK was not a problem)
Fixes also booting on 2430sdp.

Signed-off-by: Jan Weitzel <[email protected]>
Acked-by: Tony Lindgren <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 58a58c7..670f2a2 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -836,11 +836,9 @@ complete:
                                ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
                                OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
 
-               if (stat & OMAP_I2C_STAT_NACK) {
+               if (stat & OMAP_I2C_STAT_NACK)
                        err |= OMAP_I2C_STAT_NACK;
-                       omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
-                                          OMAP_I2C_CON_STP);
-               }
+
                if (stat & OMAP_I2C_STAT_AL) {
                        dev_err(dev->dev, "Arbitration lost\n");
                        err |= OMAP_I2C_STAT_AL;
-- 
1.7.0.4

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