dark0707
/
px4-firmware
forked from Archive/PX4-Autopilot
1
0
Fork 0
Code Pull Requests Activity

Add locking to the I2C bus reset API to prevent pre-emption and conflict when resetting at the same time that another transaction attempts to use the bus.

This commit is contained in:
px4dev 2012-08-22 22:24:22 -07:00
parent 6669c7faa9
commit a3b78163c3
1 changed files with 22 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
nuttx/arch/arm/src/stm32/stm32_i2c.c
View File

@ -1946,17 +1946,26 @@ int up_i2cuninitialize(FAR struct i2c_dev_s * dev)
int up_i2creset(FAR struct i2c_dev_s * dev)
{
struct stm32_i2c_priv_s * priv;
unsigned clock_count;
unsigned stretch_count;
int ret = ERROR;
irqstate_t state;
// ASSERT(dev);
struct stm32_i2c_priv_s * priv = NULL;
ASSERT(dev);
/* Get I2C private structure */
priv = ((struct stm32_i2c_inst_s *)dev)->priv;
/* Our caller must own a ref */
ASSERT(priv->refs > 0);
/* Lock out other clients */
stm32_i2c_sem_wait(dev);
/* De-init the port */
stm32_i2c_deinit(priv);
@ -1980,7 +1989,7 @@ int up_i2creset(FAR struct i2c_dev_s * dev)
if (clock_count++ > 1000)
{
return ERROR;
goto out;
}
/*
@ -1997,7 +2006,7 @@ int up_i2creset(FAR struct i2c_dev_s * dev)
if (stretch_count++ > 1000)
{
return ERROR;
goto out;
}
up_udelay(10);
@ -2041,8 +2050,15 @@ int up_i2creset(FAR struct i2c_dev_s * dev)
/* Re-init the port */
stm32_i2c_init(priv);
ret = OK;
return OK;
out:
/* release the port for re-use by other clients */
stm32_i2c_sem_post(dev);
return ret;
}
#endif /* defined(CONFIG_STM32_I2C1) || defined(CONFIG_STM32_I2C2) || defined(CONFIG_STM32_I2C3) */