diff mbox series

[1/4] iio: pressure: st_pressure: use devm_iio_triggered_buffer_setup() for buffer

Message ID 20210720074642.223293-1-aardelean@deviqon.com (mailing list archive)
State Accepted
Headers show
Series [1/4] iio: pressure: st_pressure: use devm_iio_triggered_buffer_setup() for buffer | expand

Commit Message

Alexandru Ardelean July 20, 2021, 7:46 a.m. UTC
The st_press_allocate_ring() function calls iio_triggered_buffer_setup() to
allocate a triggered buffer.

But the same can be done with devm_iio_triggered_buffer_setup() and then
the st_press_common_remove() no longer needs to manually deallocate it.

We know that the parent of the IIO device is used to manage other instances
of the devm unwind, so it can be used in the st_press_allocate_ring() as
well.

Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
---
 drivers/iio/pressure/st_pressure.h        | 5 -----
 drivers/iio/pressure/st_pressure_buffer.c | 9 ++-------
 drivers/iio/pressure/st_pressure_core.c   | 6 +-----
 3 files changed, 3 insertions(+), 17 deletions(-)

Comments

Jonathan Cameron July 24, 2021, 3:43 p.m. UTC | #1
On Tue, 20 Jul 2021 10:46:39 +0300
Alexandru Ardelean <aardelean@deviqon.com> wrote:

> The st_press_allocate_ring() function calls iio_triggered_buffer_setup() to
> allocate a triggered buffer.
> 
> But the same can be done with devm_iio_triggered_buffer_setup() and then
> the st_press_common_remove() no longer needs to manually deallocate it.
> 
> We know that the parent of the IIO device is used to manage other instances
> of the devm unwind, so it can be used in the st_press_allocate_ring() as
> well.

This raises an interesting point.  This driver mixes and matches between
hanging devm off the parent and off the iio_dev->dev.

That's probably not a good thing to do as it could lead to an odd unwind
order.  I'm pretty sure the changes here are fine, but we should take
a closer look...

Series applied to the togreg branch of iio.git and pushed out as testing.

You can do the same thing with the trigger with only slightly more complex
patch, but I'd like to discuss whether there are races because of the current
dev mix and match before that.

Thanks,

Jonathan


> 
> Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
> ---
>  drivers/iio/pressure/st_pressure.h        | 5 -----
>  drivers/iio/pressure/st_pressure_buffer.c | 9 ++-------
>  drivers/iio/pressure/st_pressure_core.c   | 6 +-----
>  3 files changed, 3 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/iio/pressure/st_pressure.h b/drivers/iio/pressure/st_pressure.h
> index 9417b3bd7513..156e6a72dc5c 100644
> --- a/drivers/iio/pressure/st_pressure.h
> +++ b/drivers/iio/pressure/st_pressure.h
> @@ -43,7 +43,6 @@ static __maybe_unused const struct st_sensors_platform_data default_press_pdata
>  
>  #ifdef CONFIG_IIO_BUFFER
>  int st_press_allocate_ring(struct iio_dev *indio_dev);
> -void st_press_deallocate_ring(struct iio_dev *indio_dev);
>  int st_press_trig_set_state(struct iio_trigger *trig, bool state);
>  #define ST_PRESS_TRIGGER_SET_STATE (&st_press_trig_set_state)
>  #else /* CONFIG_IIO_BUFFER */
> @@ -51,10 +50,6 @@ static inline int st_press_allocate_ring(struct iio_dev *indio_dev)
>  {
>  	return 0;
>  }
> -
> -static inline void st_press_deallocate_ring(struct iio_dev *indio_dev)
> -{
> -}
>  #define ST_PRESS_TRIGGER_SET_STATE NULL
>  #endif /* CONFIG_IIO_BUFFER */
>  
> diff --git a/drivers/iio/pressure/st_pressure_buffer.c b/drivers/iio/pressure/st_pressure_buffer.c
> index b651e7c31e90..25dbd5476b26 100644
> --- a/drivers/iio/pressure/st_pressure_buffer.c
> +++ b/drivers/iio/pressure/st_pressure_buffer.c
> @@ -41,13 +41,8 @@ static const struct iio_buffer_setup_ops st_press_buffer_setup_ops = {
>  
>  int st_press_allocate_ring(struct iio_dev *indio_dev)
>  {
> -	return iio_triggered_buffer_setup(indio_dev, NULL,
> -		&st_sensors_trigger_handler, &st_press_buffer_setup_ops);
> -}
> -
> -void st_press_deallocate_ring(struct iio_dev *indio_dev)
> -{
> -	iio_triggered_buffer_cleanup(indio_dev);
> +	return devm_iio_triggered_buffer_setup(indio_dev->dev.parent, indio_dev,
> +		NULL, &st_sensors_trigger_handler, &st_press_buffer_setup_ops);
>  }
>  
>  MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
> diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
> index 4ff6d40e3670..ab1c17fac807 100644
> --- a/drivers/iio/pressure/st_pressure_core.c
> +++ b/drivers/iio/pressure/st_pressure_core.c
> @@ -718,7 +718,7 @@ int st_press_common_probe(struct iio_dev *indio_dev)
>  		err = st_sensors_allocate_trigger(indio_dev,
>  						  ST_PRESS_TRIGGER_OPS);
>  		if (err < 0)
> -			goto st_press_probe_trigger_error;
> +			return err;
>  	}
>  
>  	err = iio_device_register(indio_dev);
> @@ -733,8 +733,6 @@ int st_press_common_probe(struct iio_dev *indio_dev)
>  st_press_device_register_error:
>  	if (press_data->irq > 0)
>  		st_sensors_deallocate_trigger(indio_dev);
> -st_press_probe_trigger_error:
> -	st_press_deallocate_ring(indio_dev);
>  	return err;
>  }
>  EXPORT_SYMBOL(st_press_common_probe);
> @@ -746,8 +744,6 @@ void st_press_common_remove(struct iio_dev *indio_dev)
>  	iio_device_unregister(indio_dev);
>  	if (press_data->irq > 0)
>  		st_sensors_deallocate_trigger(indio_dev);
> -
> -	st_press_deallocate_ring(indio_dev);
>  }
>  EXPORT_SYMBOL(st_press_common_remove);
>
Alexandru Ardelean July 26, 2021, 6:48 a.m. UTC | #2
On Sat, 24 Jul 2021 at 18:40, Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Tue, 20 Jul 2021 10:46:39 +0300
> Alexandru Ardelean <aardelean@deviqon.com> wrote:
>
> > The st_press_allocate_ring() function calls iio_triggered_buffer_setup() to
> > allocate a triggered buffer.
> >
> > But the same can be done with devm_iio_triggered_buffer_setup() and then
> > the st_press_common_remove() no longer needs to manually deallocate it.
> >
> > We know that the parent of the IIO device is used to manage other instances
> > of the devm unwind, so it can be used in the st_press_allocate_ring() as
> > well.
>
> This raises an interesting point.  This driver mixes and matches between
> hanging devm off the parent and off the iio_dev->dev.

iio_dev->dev.parent and the devm parent are the same reference but
coming off from different pointers

>
> That's probably not a good thing to do as it could lead to an odd unwind
> order.  I'm pretty sure the changes here are fine, but we should take
> a closer look...

hmm, let me send a follow-up series

>
> Series applied to the togreg branch of iio.git and pushed out as testing.
>

thank you :)

> You can do the same thing with the trigger with only slightly more complex
> patch, but I'd like to discuss whether there are races because of the current
> dev mix and match before that.

will send follow-up series;
i was not sure whether to send everything in one go;
maybe it would have been a good idea; but i thought this one could be
find on it's own;

>
> Thanks,
>
> Jonathan
>
>
> >
> > Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
> > ---
> >  drivers/iio/pressure/st_pressure.h        | 5 -----
> >  drivers/iio/pressure/st_pressure_buffer.c | 9 ++-------
> >  drivers/iio/pressure/st_pressure_core.c   | 6 +-----
> >  3 files changed, 3 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/iio/pressure/st_pressure.h b/drivers/iio/pressure/st_pressure.h
> > index 9417b3bd7513..156e6a72dc5c 100644
> > --- a/drivers/iio/pressure/st_pressure.h
> > +++ b/drivers/iio/pressure/st_pressure.h
> > @@ -43,7 +43,6 @@ static __maybe_unused const struct st_sensors_platform_data default_press_pdata
> >
> >  #ifdef CONFIG_IIO_BUFFER
> >  int st_press_allocate_ring(struct iio_dev *indio_dev);
> > -void st_press_deallocate_ring(struct iio_dev *indio_dev);
> >  int st_press_trig_set_state(struct iio_trigger *trig, bool state);
> >  #define ST_PRESS_TRIGGER_SET_STATE (&st_press_trig_set_state)
> >  #else /* CONFIG_IIO_BUFFER */
> > @@ -51,10 +50,6 @@ static inline int st_press_allocate_ring(struct iio_dev *indio_dev)
> >  {
> >       return 0;
> >  }
> > -
> > -static inline void st_press_deallocate_ring(struct iio_dev *indio_dev)
> > -{
> > -}
> >  #define ST_PRESS_TRIGGER_SET_STATE NULL
> >  #endif /* CONFIG_IIO_BUFFER */
> >
> > diff --git a/drivers/iio/pressure/st_pressure_buffer.c b/drivers/iio/pressure/st_pressure_buffer.c
> > index b651e7c31e90..25dbd5476b26 100644
> > --- a/drivers/iio/pressure/st_pressure_buffer.c
> > +++ b/drivers/iio/pressure/st_pressure_buffer.c
> > @@ -41,13 +41,8 @@ static const struct iio_buffer_setup_ops st_press_buffer_setup_ops = {
> >
> >  int st_press_allocate_ring(struct iio_dev *indio_dev)
> >  {
> > -     return iio_triggered_buffer_setup(indio_dev, NULL,
> > -             &st_sensors_trigger_handler, &st_press_buffer_setup_ops);
> > -}
> > -
> > -void st_press_deallocate_ring(struct iio_dev *indio_dev)
> > -{
> > -     iio_triggered_buffer_cleanup(indio_dev);
> > +     return devm_iio_triggered_buffer_setup(indio_dev->dev.parent, indio_dev,
> > +             NULL, &st_sensors_trigger_handler, &st_press_buffer_setup_ops);
> >  }
> >
> >  MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
> > diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
> > index 4ff6d40e3670..ab1c17fac807 100644
> > --- a/drivers/iio/pressure/st_pressure_core.c
> > +++ b/drivers/iio/pressure/st_pressure_core.c
> > @@ -718,7 +718,7 @@ int st_press_common_probe(struct iio_dev *indio_dev)
> >               err = st_sensors_allocate_trigger(indio_dev,
> >                                                 ST_PRESS_TRIGGER_OPS);
> >               if (err < 0)
> > -                     goto st_press_probe_trigger_error;
> > +                     return err;
> >       }
> >
> >       err = iio_device_register(indio_dev);
> > @@ -733,8 +733,6 @@ int st_press_common_probe(struct iio_dev *indio_dev)
> >  st_press_device_register_error:
> >       if (press_data->irq > 0)
> >               st_sensors_deallocate_trigger(indio_dev);
> > -st_press_probe_trigger_error:
> > -     st_press_deallocate_ring(indio_dev);
> >       return err;
> >  }
> >  EXPORT_SYMBOL(st_press_common_probe);
> > @@ -746,8 +744,6 @@ void st_press_common_remove(struct iio_dev *indio_dev)
> >       iio_device_unregister(indio_dev);
> >       if (press_data->irq > 0)
> >               st_sensors_deallocate_trigger(indio_dev);
> > -
> > -     st_press_deallocate_ring(indio_dev);
> >  }
> >  EXPORT_SYMBOL(st_press_common_remove);
> >
>
diff mbox series

Patch

diff --git a/drivers/iio/pressure/st_pressure.h b/drivers/iio/pressure/st_pressure.h
index 9417b3bd7513..156e6a72dc5c 100644
--- a/drivers/iio/pressure/st_pressure.h
+++ b/drivers/iio/pressure/st_pressure.h
@@ -43,7 +43,6 @@  static __maybe_unused const struct st_sensors_platform_data default_press_pdata
 
 #ifdef CONFIG_IIO_BUFFER
 int st_press_allocate_ring(struct iio_dev *indio_dev);
-void st_press_deallocate_ring(struct iio_dev *indio_dev);
 int st_press_trig_set_state(struct iio_trigger *trig, bool state);
 #define ST_PRESS_TRIGGER_SET_STATE (&st_press_trig_set_state)
 #else /* CONFIG_IIO_BUFFER */
@@ -51,10 +50,6 @@  static inline int st_press_allocate_ring(struct iio_dev *indio_dev)
 {
 	return 0;
 }
-
-static inline void st_press_deallocate_ring(struct iio_dev *indio_dev)
-{
-}
 #define ST_PRESS_TRIGGER_SET_STATE NULL
 #endif /* CONFIG_IIO_BUFFER */
 
diff --git a/drivers/iio/pressure/st_pressure_buffer.c b/drivers/iio/pressure/st_pressure_buffer.c
index b651e7c31e90..25dbd5476b26 100644
--- a/drivers/iio/pressure/st_pressure_buffer.c
+++ b/drivers/iio/pressure/st_pressure_buffer.c
@@ -41,13 +41,8 @@  static const struct iio_buffer_setup_ops st_press_buffer_setup_ops = {
 
 int st_press_allocate_ring(struct iio_dev *indio_dev)
 {
-	return iio_triggered_buffer_setup(indio_dev, NULL,
-		&st_sensors_trigger_handler, &st_press_buffer_setup_ops);
-}
-
-void st_press_deallocate_ring(struct iio_dev *indio_dev)
-{
-	iio_triggered_buffer_cleanup(indio_dev);
+	return devm_iio_triggered_buffer_setup(indio_dev->dev.parent, indio_dev,
+		NULL, &st_sensors_trigger_handler, &st_press_buffer_setup_ops);
 }
 
 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
index 4ff6d40e3670..ab1c17fac807 100644
--- a/drivers/iio/pressure/st_pressure_core.c
+++ b/drivers/iio/pressure/st_pressure_core.c
@@ -718,7 +718,7 @@  int st_press_common_probe(struct iio_dev *indio_dev)
 		err = st_sensors_allocate_trigger(indio_dev,
 						  ST_PRESS_TRIGGER_OPS);
 		if (err < 0)
-			goto st_press_probe_trigger_error;
+			return err;
 	}
 
 	err = iio_device_register(indio_dev);
@@ -733,8 +733,6 @@  int st_press_common_probe(struct iio_dev *indio_dev)
 st_press_device_register_error:
 	if (press_data->irq > 0)
 		st_sensors_deallocate_trigger(indio_dev);
-st_press_probe_trigger_error:
-	st_press_deallocate_ring(indio_dev);
 	return err;
 }
 EXPORT_SYMBOL(st_press_common_probe);
@@ -746,8 +744,6 @@  void st_press_common_remove(struct iio_dev *indio_dev)
 	iio_device_unregister(indio_dev);
 	if (press_data->irq > 0)
 		st_sensors_deallocate_trigger(indio_dev);
-
-	st_press_deallocate_ring(indio_dev);
 }
 EXPORT_SYMBOL(st_press_common_remove);