Re: [PATCH v2] soundwire: debugfs: use controller id and link_id for debugfs

From: Pierre-Louis Bossart
Date: Tue Sep 07 2021 - 12:08:34 EST




On 9/7/21 5:53 AM, Srinivas Kandagatla wrote:
> link_id can be zero and if we have multiple controller instances
> in a system like Qualcomm debugfs will end-up with duplicate namespace
> resulting in incorrect debugfs entries.
>
> Using bus-id and link-id combination should give a unique debugfs directory
> entry and should fix below warning too.
> "debugfs: Directory 'master-0' with parent 'soundwire' already present!"
>
> Fixes: bf03473d5bcc ("soundwire: add debugfs support")
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>

> ---
> Changes since v1:
> Added Link ID along with bus id.
>
> drivers/soundwire/debugfs.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/soundwire/debugfs.c b/drivers/soundwire/debugfs.c
> index b6cad0d59b7b..49900cd207bc 100644
> --- a/drivers/soundwire/debugfs.c
> +++ b/drivers/soundwire/debugfs.c
> @@ -19,7 +19,7 @@ void sdw_bus_debugfs_init(struct sdw_bus *bus)
> return;
>
> /* create the debugfs master-N */
> - snprintf(name, sizeof(name), "master-%d", bus->link_id);
> + snprintf(name, sizeof(name), "master-%d-%d", bus->id, bus->link_id);
> bus->debugfs = debugfs_create_dir(name, sdw_debugfs_root);
> }
>
>