Re: [RFC PATCH 04/12] iio: buffer: add index to the first IIO buffer dir and symlink it back

[Jonathan Cameron]

On Tue, 17 Nov 2020 18:23:32 +0200
Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote:

> This change makes it so that the first buffer directory is named 'buffer0'
> and moves the 'scan_elements' under it.
> 
> For backwards compatibility these folders are symlinked back to the
> original folders.
Well done on your patch breakdown here.  Makes the actual switch nice
and simple in this patch.

Looks good to me.

Thanks,

Jonathan

> 
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> ---
>  drivers/iio/industrialio-buffer.c | 38 +++++++++++++++++++++++++++----
>  1 file changed, 33 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
> index 8b31faf049a5..62c8bd6b67cd 100644
> --- a/drivers/iio/industrialio-buffer.c
> +++ b/drivers/iio/industrialio-buffer.c
> @@ -1346,7 +1346,8 @@ static void iio_sysfs_del_attrs(struct kobject *kobj, struct attribute **ptr)
>  }
>  
>  static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer,
> -					     struct iio_dev *indio_dev)
> +					     struct iio_dev *indio_dev,
> +					     unsigned int idx)
>  {
>  	struct iio_dev_attr *p;
>  	struct attribute **attr;
> @@ -1378,7 +1379,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer,
>  	buffer->buffer_attrs = attr;
>  
>  	ret = kobject_init_and_add(&buffer->buffer_dir, &iio_buffer_dir_ktype,
> -				   &indio_dev->dev.kobj, "buffer");
> +				   &indio_dev->dev.kobj, "buffer%u", idx);
>  	if (ret)
>  		goto error_buffer_free_attrs;
>  
> @@ -1423,7 +1424,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer,
>  	}
>  
>  	ret = kobject_init_and_add(&buffer->scan_el_dir, &iio_scan_el_dir_ktype,
> -				   &indio_dev->dev.kobj, "scan_elements");
> +				   &buffer->buffer_dir, "scan_elements");
>  	if (ret)
>  		goto error_free_scan_attrs;
>  
> @@ -1454,11 +1455,13 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer,
>  	return ret;
>  }
>  
> +static void __iio_buffer_free_sysfs_and_mask(struct iio_buffer *buffer);
> +
>  int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
>  {
>  	struct iio_buffer *buffer = indio_dev->buffer;
>  	const struct iio_chan_spec *channels;
> -	int i;
> +	int i, ret;
>  
>  	channels = indio_dev->channels;
>  	if (channels) {
> @@ -1472,7 +1475,29 @@ int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
>  	if (!buffer)
>  		return 0;
>  
> -	return __iio_buffer_alloc_sysfs_and_mask(buffer, indio_dev);
> +	ret = __iio_buffer_alloc_sysfs_and_mask(buffer, indio_dev, 0);
> +	if (ret)
> +		return ret;
> +
> +	ret = sysfs_create_link(&indio_dev->dev.kobj,
> +				&indio_dev->buffer->buffer_dir,
> +				"buffer");
> +	if (ret)
> +		goto error_free_sysfs_and_mask;
> +
> +	ret = sysfs_create_link(&indio_dev->dev.kobj,
> +				&indio_dev->buffer->scan_el_dir,
> +				"scan_elements");
> +	if (ret)
> +		goto error_remove_buffer_dir_link;
> +
> +	return 0;
> +
> +error_remove_buffer_dir_link:
> +	sysfs_remove_link(&indio_dev->dev.kobj, "buffer");
> +error_free_sysfs_and_mask:
> +	__iio_buffer_free_sysfs_and_mask(buffer);
> +	return ret;
>  }
>  
>  static void __iio_buffer_free_sysfs_and_mask(struct iio_buffer *buffer)
> @@ -1494,6 +1519,9 @@ void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
>  	if (!buffer)
>  		return;
>  
> +	sysfs_remove_link(&indio_dev->dev.kobj, "scan_elements");
> +	sysfs_remove_link(&indio_dev->dev.kobj, "buffer");
> +
>  	__iio_buffer_free_sysfs_and_mask(buffer);
>  }
>