Re: [PATCH v1 04/10] device property: add fwnode_get_parent()

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

On Tuesday, June 30, 2015 04:55:02 PM Tomeu Vizoso wrote:
> So we can query the parent of a fwnode without having to resort to API
> that is specific to a firmware data format.
> 
> Also adds a acpi_get_parent_dev() function to retrieve the parent
> of an acpi_device. acpi_get_parent() already existed but it works with
> acpi_handles.
> 
> The interface covers both ACPI and Device Trees.
> 
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>

This one looks good to me.


> ---
> 
>  drivers/base/property.c  | 23 +++++++++++++++++++++++
>  include/acpi/acpi_bus.h  |  5 +++++
>  include/linux/acpi.h     |  5 +++++
>  include/linux/property.h |  2 ++
>  4 files changed, 35 insertions(+)
> 
> diff --git a/drivers/base/property.c b/drivers/base/property.c
> index f3f6d16..a7fb46b 100644
> --- a/drivers/base/property.c
> +++ b/drivers/base/property.c
> @@ -533,3 +533,26 @@ bool device_dma_is_coherent(struct device *dev)
>  	return coherent;
>  }
>  EXPORT_SYMBOL_GPL(device_dma_is_coherent);
> +
> +/**
> + * fwnode_get_parent - return the parent node of a device node
> + * @fwnode: Device node to find the parent node of
> + */
> +struct fwnode_handle *fwnode_get_parent(struct fwnode_handle *fwnode)
> +{
> +	if (is_of_node(fwnode)) {
> +		struct device_node *node = to_of_node(fwnode);
> +
> +		if (node->parent)
> +			return &node->parent->fwnode;
> +	} else if (is_acpi_node(fwnode)) {
> +		struct acpi_device *node;
> +
> +		node = acpi_get_parent_dev(to_acpi_node(fwnode));
> +		if (node)
> +			return acpi_fwnode_handle(node);
> +	}
> +
> +	return NULL;
> +}
> +EXPORT_SYMBOL_GPL(fwnode_get_parent);
> diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
> index 83061ca..93c42a6 100644
> --- a/include/acpi/acpi_bus.h
> +++ b/include/acpi/acpi_bus.h
> @@ -436,6 +436,11 @@ static inline void *acpi_driver_data(struct acpi_device *d)
>  	return d->driver_data;
>  }
>  
> +static inline struct acpi_device *acpi_get_parent_dev(struct acpi_device *adev)
> +{
> +	return adev->parent;
> +}
> +
>  #define to_acpi_device(d)	container_of(d, struct acpi_device, dev)
>  #define to_acpi_driver(d)	container_of(d, struct acpi_driver, drv)
>  
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index ed79b06..fc84e42 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -804,6 +804,11 @@ static inline struct acpi_device *acpi_get_next_child(struct device *dev,
>  	return NULL;
>  }
>  
> +static inline struct acpi_device *acpi_get_parent_dev(struct acpi_device *adev)
> +{
> +	return NULL;
> +}
> +
>  #endif
>  
>  #endif	/*_LINUX_ACPI_H*/
> diff --git a/include/linux/property.h b/include/linux/property.h
> index 76ebde9..f47092d 100644
> --- a/include/linux/property.h
> +++ b/include/linux/property.h
> @@ -63,6 +63,8 @@ int fwnode_property_read_string(struct fwnode_handle *fwnode,
>  struct fwnode_handle *device_get_next_child_node(struct device *dev,
>  						 struct fwnode_handle *child);
>  
> +struct fwnode_handle *fwnode_get_parent(struct fwnode_handle *fwnode);
> +
>  #define device_for_each_child_node(dev, child) \
>  	for (child = device_get_next_child_node(dev, NULL); child; \
>  	     child = device_get_next_child_node(dev, child))
> 

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.