On Wed, Nov 09, 2016 at 02:09:38PM +0000, Paul Burton wrote:

On Tuesday, 8 November 2016 08:13:37 GMT Jan Glauber wrote:

quoted

On Mon, Nov 07, 2016 at 08:09:20PM +0000, Paul Burton wrote:

quoted

Commit 70121f7f3725 ("i2c: octeon: thunderx: Limit register access
retries") attempted to replace potentially infinite loops with ones
which will time out using readq_poll_timeout, but in doing so it
inverted the condition for exiting this loop.

Tested on a Rhino Labs UTM-8 with Octeon CN7130.

Signed-off-by: Paul Burton <redacted>
Cc: Jan Glauber <redacted>
Cc: David Daney <redacted>
Cc: Wolfram Sang <redacted>
Cc: linux-i2c@vger.kernel.org

---

Acked-by: Jan Glauber <redacted>

Thanks for spotting this. I think this should go into stable too for
4.8, so adding Cc: stable@vger.kernel.org.

Hi Jan,

...but the bad patch was only merged for v4.9-rc1?

true, I've misread it.

Thanks,
    Paul

quoted

quoted

 drivers/i2c/busses/i2c-octeon-core.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-octeon-core.h

b/drivers/i2c/busses/i2c-octeon-core.h index 1db7c83..d980406 100644

--- a/drivers/i2c/busses/i2c-octeon-core.h
+++ b/drivers/i2c/busses/i2c-octeon-core.h

@@ -146,8 +146,9 @@ static inline void octeon_i2c_reg_write(struct

octeon_i2c *i2c, u64 eop_reg, u8> 
 	__raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + 

SW_TWSI(i2c));

quoted

quoted

-	readq_poll_timeout(i2c->twsi_base + SW_TWSI(i2c), tmp, tmp & 

SW_TWSI_V,

quoted

quoted

-			   I2C_OCTEON_EVENT_WAIT, i2c->adap.timeout);
+	readq_poll_timeout(i2c->twsi_base + SW_TWSI(i2c), tmp,
+			   !(tmp & SW_TWSI_V), I2C_OCTEON_EVENT_WAIT,
+			   i2c->adap.timeout);

 }
 
 #define octeon_i2c_ctl_write(i2c, val)					\

@@ -173,7 +174,7 @@ static inline int octeon_i2c_reg_read(struct

octeon_i2c *i2c, u64 eop_reg,> 
 	__raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base +
 	SW_TWSI(i2c));
 	
 	ret = readq_poll_timeout(i2c->twsi_base + SW_TWSI(i2c), tmp,

-				 tmp & SW_TWSI_V, I2C_OCTEON_EVENT_WAIT,
+				 !(tmp & SW_TWSI_V), I2C_OCTEON_EVENT_WAIT,

 				 i2c->adap.timeout);
 	
 	if (error)
 	
 		*error = ret;