From: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxxx>
In case the hold bit is not needed we are carrying the old values.
Fix the same by resetting the bit when not needed.
Fixes the sporadic i2c bus lockups on National Instruments
Zynq-based devices.
Fixes: df8eb5691c48 ("i2c: Add driver for Cadence I2C controller")
Acked-by: Michal Simek <michal.simek@xxxxxxxxxx>
Reported-and-tested-by: Kyle Roeschley <kyle.roeschley@xxxxxx>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxxx>
---
v5:
fix some typos
v4:
update fixes tag
v3:
Add fixes and Ack
v2:
Update commit log
Also check if the hold_flag
drivers/i2c/busses/i2c-cadence.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c
index 9260574..42c38fd 100644
--- a/drivers/i2c/busses/i2c-cadence.c
+++ b/drivers/i2c/busses/i2c-cadence.c
@@ -628,8 +628,10 @@ static void cdns_i2c_mrecv(struct cdns_i2c *id)
* Check for the message size against FIFO depth and set the
* 'hold bus' bit if it is greater than FIFO depth.
*/
- if (id->recv_count > CDNS_I2C_FIFO_DEPTH)
+ if ((id->recv_count > CDNS_I2C_FIFO_DEPTH) || id->bus_hold_flag)
ctrl_reg |= CDNS_I2C_CR_HOLD;
+ else
+ ctrl_reg = ctrl_reg & ~CDNS_I2C_CR_HOLD;
cdns_i2c_writereg(ctrl_reg, CDNS_I2C_CR_OFFSET);
@@ -686,8 +688,11 @@ static void cdns_i2c_msend(struct cdns_i2c *id)
* Check for the message size against FIFO depth and set the
* 'hold bus' bit if it is greater than FIFO depth.
*/
- if (id->send_count > CDNS_I2C_FIFO_DEPTH)
+ if ((id->send_count > CDNS_I2C_FIFO_DEPTH) || id->bus_hold_flag)
ctrl_reg |= CDNS_I2C_CR_HOLD;
+ else
+ ctrl_reg = ctrl_reg & ~CDNS_I2C_CR_HOLD;
+
cdns_i2c_writereg(ctrl_reg, CDNS_I2C_CR_OFFSET);
/* Clear the interrupts in interrupt status register. */
--
2.1.1
