[v6,6/6] iio: imu: st_lsm6dsx: prohibit the use of events and buffered reads simultaneously
diff mbox series

Message ID 20190909112846.55280-6-sean@geanix.com
State New
Headers show
Series
  • [v6,1/6] iio: imu: st_lsm6dsx: move interrupt thread to core
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Commit Message

Sean Nyekjaer Sept. 9, 2019, 11:28 a.m. UTC
When events and buffered reads is enabled simultaneously, and the first
event accours the interrupt pin stays high.

This can be reverted when we find a solution to allow events and
buffered reads simultaneously.

Signed-off-by: Sean Nyekjaer <sean@geanix.com>
---
Changes since v4:
 * Use fifo configuration mutex to prevent a race in hw->enable_event check.

Changes since v5:
 * Updated do not return without unlocking mutexes
 * Lock mutex before unlock
 * Runtime tested ;-)

 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c |  5 +++++
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c   | 13 ++++++++++---
 2 files changed, 15 insertions(+), 3 deletions(-)

Comments

Lorenzo Bianconi Sept. 9, 2019, 11:55 a.m. UTC | #1
> When events and buffered reads is enabled simultaneously, and the first
> event accours the interrupt pin stays high.
> 
> This can be reverted when we find a solution to allow events and
> buffered reads simultaneously.
> 
> Signed-off-by: Sean Nyekjaer <sean@geanix.com>
> ---
> Changes since v4:
>  * Use fifo configuration mutex to prevent a race in hw->enable_event check.
> 
> Changes since v5:
>  * Updated do not return without unlocking mutexes
>  * Lock mutex before unlock
>  * Runtime tested ;-)
> 

[...]

> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
> @@ -1340,8 +1340,12 @@ static int st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
>  	if (type != IIO_EV_TYPE_THRESH)
>  		return -EINVAL;
>  
> -	if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS)
> -		return -EBUSY;
> +	mutex_lock(&hw->conf_lock);
> +
> +	if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS) {
> +		err = -EBUSY;
> +		goto out;
> +	}

This patch is still broken!!! Returning in case of error you need to relase the
lock.

>  
>  	/* do not enable events if they are already enabled */
>  	if (state && hw->enable_event)
> @@ -1357,7 +1361,10 @@ static int st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
>  
>  	hw->enable_event = state;
>  
> -	return 0;
> +out:
> +	mutex_unlock(&hw->conf_lock);
> +
> +	return err;
>  }
>  
>  int st_lsm6dsx_set_watermark(struct iio_dev *iio_dev, unsigned int val)
> -- 
> 2.23.0
>
Sean Nyekjaer Sept. 9, 2019, 11:59 a.m. UTC | #2
On 09/09/2019 13.55, Lorenzo Bianconi wrote:
>> When events and buffered reads is enabled simultaneously, and the first
>> event accours the interrupt pin stays high.
>>
>> This can be reverted when we find a solution to allow events and
>> buffered reads simultaneously.
>>
>> Signed-off-by: Sean Nyekjaer <sean@geanix.com>
>> ---
>> Changes since v4:
>>   * Use fifo configuration mutex to prevent a race in hw->enable_event check.
>>
>> Changes since v5:
>>   * Updated do not return without unlocking mutexes
>>   * Lock mutex before unlock
>>   * Runtime tested ;-)
>>
> 
> [...]
> 
>> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>> @@ -1340,8 +1340,12 @@ static int st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
>>   	if (type != IIO_EV_TYPE_THRESH)
>>   		return -EINVAL;
>>   
>> -	if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS)
>> -		return -EBUSY;
>> +	mutex_lock(&hw->conf_lock);
>> +
>> +	if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS) {
>> +		err = -EBUSY;
>> +		goto out;
>> +	}
> 
> This patch is still broken!!! Returning in case of error you need to relase the
> lock.
> 

Hmm,

please read below this:

-	return 0;
+out:
+	mutex_unlock(&hw->conf_lock);
+
+	return err;


>>   
>>   	/* do not enable events if they are already enabled */
>>   	if (state && hw->enable_event)
>> @@ -1357,7 +1361,10 @@ static int st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
>>   
>>   	hw->enable_event = state;
>>   
>> -	return 0;
>> +out:
>> +	mutex_unlock(&hw->conf_lock);
>> +
>> +	return err;
>>   }
>>   
>>   int st_lsm6dsx_set_watermark(struct iio_dev *iio_dev, unsigned int val)
>> -- 
>> 2.23.0
>>
Sean Nyekjaer Sept. 9, 2019, 12:01 p.m. UTC | #3
On 09/09/2019 13.59, Sean Nyekjaer wrote:
> 
> 
> On 09/09/2019 13.55, Lorenzo Bianconi wrote:
>>> When events and buffered reads is enabled simultaneously, and the first
>>> event accours the interrupt pin stays high.
>>>
>>> This can be reverted when we find a solution to allow events and
>>> buffered reads simultaneously.
>>>
>>> Signed-off-by: Sean Nyekjaer <sean@geanix.com>
>>> ---
>>> Changes since v4:
>>>   * Use fifo configuration mutex to prevent a race in 
>>> hw->enable_event check.
>>>
>>> Changes since v5:
>>>   * Updated do not return without unlocking mutexes
>>>   * Lock mutex before unlock
>>>   * Runtime tested ;-)
>>>
>>
>> [...]
>>
>>> --- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>>> +++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
>>> @@ -1340,8 +1340,12 @@ static int 
>>> st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
>>>       if (type != IIO_EV_TYPE_THRESH)
>>>           return -EINVAL;
>>> -    if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS)
>>> -        return -EBUSY;
>>> +    mutex_lock(&hw->conf_lock);
>>> +
>>> +    if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS) {
>>> +        err = -EBUSY;
>>> +        goto out;
>>> +    }
>>
>> This patch is still broken!!! Returning in case of error you need to 
>> relase the
>> lock.
>>
> 
> Hmm,
> 
> please read below this:
> 
> -    return 0;
> +out:
> +    mutex_unlock(&hw->conf_lock);
> +
> +    return err;
> >

I see what you mean...
I will update this function with:
goto's :-)

/Sean

>>>       /* do not enable events if they are already enabled */
>>>       if (state && hw->enable_event)
>>> @@ -1357,7 +1361,10 @@ static int 
>>> st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
>>>       hw->enable_event = state;
>>> -    return 0;
>>> +out:
>>> +    mutex_unlock(&hw->conf_lock);
>>> +
>>> +    return err;
>>>   }
>>>   int st_lsm6dsx_set_watermark(struct iio_dev *iio_dev, unsigned int 
>>> val)
>>> -- 
>>> 2.23.0
>>>

Patch
diff mbox series

diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
index ef579650fd52..b87a1872bc60 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
@@ -603,6 +603,11 @@  int st_lsm6dsx_update_fifo(struct st_lsm6dsx_sensor *sensor, bool enable)
 
 	mutex_lock(&hw->conf_lock);
 
+	if (hw->enable_event) {
+		err = -EBUSY;
+		goto out;
+	}
+
 	if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS) {
 		err = st_lsm6dsx_flush_fifo(hw);
 		if (err < 0)
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
index 00ba14d15c13..2616036ce953 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -1340,8 +1340,12 @@  static int st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
 	if (type != IIO_EV_TYPE_THRESH)
 		return -EINVAL;
 
-	if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS)
-		return -EBUSY;
+	mutex_lock(&hw->conf_lock);
+
+	if (hw->fifo_mode != ST_LSM6DSX_FIFO_BYPASS) {
+		err = -EBUSY;
+		goto out;
+	}
 
 	/* do not enable events if they are already enabled */
 	if (state && hw->enable_event)
@@ -1357,7 +1361,10 @@  static int st_lsm6dsx_write_event_config(struct iio_dev *iio_dev,
 
 	hw->enable_event = state;
 
-	return 0;
+out:
+	mutex_unlock(&hw->conf_lock);
+
+	return err;
 }
 
 int st_lsm6dsx_set_watermark(struct iio_dev *iio_dev, unsigned int val)