From ccee1a4cdcd02e748d39d2b121f7f82041893121 Mon Sep 17 00:00:00 2001 From: Jan Glauber Date: Fri, 9 Dec 2016 10:31:55 +0100 Subject: [PATCH] i2c: octeon: thunderx: TWSI software reset in recovery 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 Signed-off-by: Wolfram Sang --- 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 419b54bfc7c7..0b020703017d 100644 --- a/drivers/i2c/busses/i2c-octeon-core.c +++ b/drivers/i2c/busses/i2c-octeon-core.c @@ -791,6 +791,9 @@ 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