diff options
| author | Marek Vasut <marex@denx.de> | 2012-11-21 06:19:06 +0100 |
|---|---|---|
| committer | Wolfram Sang <w.sang@pengutronix.de> | 2013-01-21 16:26:29 +0100 |
| commit | 85de7fac3990cf0c0736edc83856add2e648c76a (patch) | |
| tree | 1f6600aceb397d1e12ae372a8674f3ca7fc3f5f6 /drivers/i2c | |
| parent | 7d1f9aeff1ee4a20b1aeb377dd0f579fe9647619 (diff) | |
i2c: mxs: Fix misuse init_completion
The init_completion() call does reinit not only the variable carrying
the flag that the completion finished, but also initialized the
waitqueue associated with the completion. On the contrary, the
INIT_COMPLETION() call only reinits the flag.
In case there was anything still stuck in the waitqueue, subsequent call
to init_completion() would be able to create possible race condition. This
patch uses the proper function and moves init_completion() into .probe() call
of the driver, to be issued only once.
Note that such scenario is impossible, since two threads can never enter the
mxs_i2c_xfer_msg(), since whole this section is protected by mutex in I2C core.
This by no means allows this issue to exit though.
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-mxs.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c index 1b1a936eccc9..977c4d596b69 100644 --- a/drivers/i2c/busses/i2c-mxs.c +++ b/drivers/i2c/busses/i2c-mxs.c @@ -316,7 +316,7 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, if (msg->len == 0) return -EINVAL; - init_completion(&i2c->cmd_complete); + INIT_COMPLETION(i2c->cmd_complete); i2c->cmd_err = 0; ret = mxs_i2c_dma_setup_xfer(adap, msg, flags); @@ -473,6 +473,8 @@ static int mxs_i2c_probe(struct platform_device *pdev) i2c->dev = dev; i2c->speed = &mxs_i2c_95kHz_config; + init_completion(&i2c->cmd_complete); + if (dev->of_node) { err = mxs_i2c_get_ofdata(i2c); if (err) |