From: Jan Glauber jglauber@cavium.com
I've seen i2c recovery reporting long loops of:
[ 1035.887818] i2c i2c-4: SCL is stuck low, exit recovery [ 1037.999748] i2c i2c-4: SCL is stuck low, exit recovery [ 1040.111694] i2c i2c-4: SCL is stuck low, exit recovery ...
Add a TWSI software reset which clears the status and STA,STP,IFLG in SW_TWSI_EOP_TWSI_CTL.
With this the recovery works fine and above message is not seen.
Signed-off-by: Jan Glauber jglauber@cavium.com Signed-off-by: Wolfram Sang wsa@the-dreams.de (cherry picked from commit ccee1a4cdcd02e748d39d2b121f7f82041893121) Signed-off-by: Vadim Lomovtsev Vadim.Lomovtsev@caviumnetworks.com --- drivers/i2c/busses/i2c-octeon-core.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c index 5e63b17..2b8a7bf 100644 --- a/drivers/i2c/busses/i2c-octeon-core.c +++ b/drivers/i2c/busses/i2c-octeon-core.c @@ -789,6 +789,9 @@ static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap) struct octeon_i2c *i2c = i2c_get_adapdata(adap);
octeon_i2c_hlc_disable(i2c); + octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0); + /* wait for software reset to settle */ + udelay(5);
/* * Bring control register to a good state regardless