diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-core.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c index db20a2841b75..3de549436992 100644 --- a/drivers/i2c/busses/i2c-designware-core.c +++ b/drivers/i2c/busses/i2c-designware-core.c @@ -583,11 +583,21 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) ret = wait_for_completion_timeout(&dev->cmd_complete, HZ); if (ret == 0) { dev_err(dev->dev, "controller timed out\n"); + /* i2c_dw_init implicitly disables the adapter */ i2c_dw_init(dev); ret = -ETIMEDOUT; goto done; } + /* + * We must disable the adapter before unlocking the &dev->lock mutex + * below. Otherwise the hardware might continue generating interrupts + * which in turn causes a race condition with the following transfer. + * Needs some more investigation if the additional interrupts are + * a hardware bug or this driver doesn't handle them correctly yet. + */ + __i2c_dw_enable(dev, false); + if (dev->msg_err) { ret = dev->msg_err; goto done; @@ -595,8 +605,6 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) /* no error */ if (likely(!dev->cmd_err)) { - /* Disable the adapter */ - __i2c_dw_enable(dev, false); ret = num; goto done; } |