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i2c: davinci: Refactor i2c_davinci_wait_bus_not_busy() 

There are several problems in the function:
- "to_cnt" variable does nothing
- schedule_timeout() call without setting current state does nothing
- "allow_sleep" parameter is not really used

Refactor the function so that it really tries to wait. In case of timeout try
to recover the bus.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Alexander Sverdlin 2015-06-09 12:58:29 +02:00 committed by Wolfram Sang
parent dd1aa2524b
commit 72a956c556
1 changed files with 18 additions and 22 deletions
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38
drivers/i2c/busses/i2c-davinci.c
View File

@ -350,29 +350,25 @@ static struct i2c_bus_recovery_info davinci_i2c_scl_recovery_info = {
/*
* Waiting for bus not busy
*/
static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev,
char allow_sleep)
static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev)
{
unsigned long timeout;
static u16 to_cnt;
unsigned long timeout = jiffies + dev->adapter.timeout;
timeout = jiffies + dev->adapter.timeout;
while (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG)
& DAVINCI_I2C_STR_BB) {
if (to_cnt <= DAVINCI_I2C_MAX_TRIES) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev,
"timeout waiting for bus ready\n");
to_cnt++;
return -ETIMEDOUT;
} else {
to_cnt = 0;
do {
if (!(davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) & DAVINCI_I2C_STR_BB))
return 0;
schedule_timeout_uninterruptible(1);
} while (time_before_eq(jiffies, timeout));
dev_warn(dev->dev, "timeout waiting for bus ready\n");
i2c_recover_bus(&dev->adapter);
}
}
if (allow_sleep)
schedule_timeout(1);
}
/*
* if bus is still "busy" here, it's most probably a HW problem like
* short-circuit
*/
if (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) & DAVINCI_I2C_STR_BB)
return -EIO;
return 0;
}
@ -505,7 +501,7 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num);
ret = i2c_davinci_wait_bus_not_busy(dev, 1);
ret = i2c_davinci_wait_bus_not_busy(dev);
if (ret < 0) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
return ret;