Commit 0b884fe7 authored by Chunyan Zhang's avatar Chunyan Zhang Committed by Wolfram Sang

i2c: sprd: use a specific timeout to avoid system hang up issue

If the i2c device SCL bus being pulled up due to some exception before
message transfer done, the system cannot receive the completing interrupt
signal any more, it would not exit waiting loop until MAX_SCHEDULE_TIMEOUT
jiffies eclipse, that would make the system seemed hang up. To avoid that
happen, this patch adds a specific timeout for message transfer.

Fixes: 8b9ec071 ("i2c: Add Spreadtrum I2C controller driver")
Signed-off-by: default avatarLinhua Xu <linhua.xu@unisoc.com>
Signed-off-by: default avatarChunyan Zhang <chunyan.zhang@unisoc.com>
[wsa: changed errno to ETIMEDOUT]
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent e71ba945
......@@ -72,6 +72,8 @@
/* timeout (ms) for pm runtime autosuspend */
#define SPRD_I2C_PM_TIMEOUT 1000
/* timeout (ms) for transfer message */
#define I2C_XFER_TIMEOUT 1000
/* SPRD i2c data structure */
struct sprd_i2c {
......@@ -244,6 +246,7 @@ static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap,
struct i2c_msg *msg, bool is_last_msg)
{
struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
unsigned long time_left;
i2c_dev->msg = msg;
i2c_dev->buf = msg->buf;
......@@ -273,7 +276,10 @@ static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap,
sprd_i2c_opt_start(i2c_dev);
wait_for_completion(&i2c_dev->complete);
time_left = wait_for_completion_timeout(&i2c_dev->complete,
msecs_to_jiffies(I2C_XFER_TIMEOUT));
if (!time_left)
return -ETIMEDOUT;
return i2c_dev->err;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment