i2c: octeon: Avoid sending STOP during recovery

[cascardo/linux.git] / drivers / i2c / busses / i2c-octeon-core.c

diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
index f322242..7d4df83 100644 (file)
--- a/drivers/i2c/busses/i2c-octeon-core.c
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -783,13 +783,14 @@ static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap)
 {
        struct octeon_i2c *i2c = i2c_get_adapdata(adap);
 
+       octeon_i2c_hlc_disable(i2c);
+
        /*
-        * The stop resets the state machine, does not _transmit_ STOP unless
-        * engine was active.
+        * Bring control register to a good state regardless
+        * of HLC state.
         */
-       octeon_i2c_stop(i2c);
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
 
-       octeon_i2c_hlc_disable(i2c);
        octeon_i2c_write_int(i2c, 0);
 }
 
@@ -797,6 +798,15 @@ static void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap)
 {
        struct octeon_i2c *i2c = i2c_get_adapdata(adap);
 
+       /*
+        * Generate STOP to finish the unfinished transaction.
+        * Can't generate STOP via the TWSI CTL register
+        * since it could bring the TWSI controller into an inoperable state.
+        */
+       octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR);
+       udelay(5);
+       octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR);
+       udelay(5);
        octeon_i2c_write_int(i2c, 0);
 }