Re: [PATCH net-next 04/11] net: dsa: debugfs: add tag_protocol

[Florian Fainelli]

On 08/14/2017 03:22 PM, Vivien Didelot wrote:
> Add a debug filesystem "tag_protocol" entry to query the switch tagging
> protocol through the .get_tag_protocol operation.
> 
>     # cat switch1/tag_protocol
>     EDSA
> 
> Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
> ---
>  net/dsa/debugfs.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 54 insertions(+)
> 
> diff --git a/net/dsa/debugfs.c b/net/dsa/debugfs.c
> index 5607efdb924d..30a732e86161 100644
> --- a/net/dsa/debugfs.c
> +++ b/net/dsa/debugfs.c
> @@ -109,6 +109,55 @@ static int dsa_debugfs_create_file(struct dsa_switch *ds, struct dentry *dir,
>  	return 0;
>  }
>  
> +static int dsa_debugfs_tag_protocol_read(struct dsa_switch *ds, int id,
> +					 struct seq_file *seq)
> +{
> +	enum dsa_tag_protocol proto;
> +
> +	if (!ds->ops->get_tag_protocol)
> +		return -EOPNOTSUPP;
> +
> +	proto = ds->ops->get_tag_protocol(ds);
> +
> +	switch (proto) {
> +	case DSA_TAG_PROTO_NONE:
> +		seq_puts(seq, "NONE\n");

Might be worth adding a helper function: does dsa_tag_protocol_to_str()
which is in include/net/dsa.h so it's easy to keep in sync when new
taggers are added, then you can just do:

	seq_puts(seq, dsa_tag_protocol_to_str(proto));

and/or use a temporary buffer for adding the trailing newline.
-- 
Florian