Re: [PATCH v13 01/10] device property: Add remote endpoint to devcon matcher

[Heikki Krogerus]

On Fri, Mar 03, 2023 at 10:33:41PM +0800, Pin-yen Lin wrote:
> From: Prashant Malani <pmalani@xxxxxxxxxxxx>
> 
> When searching the device graph for device matches, check the
> remote-endpoint itself for a match.
> 
> Some drivers register devices for individual endpoints. This allows
> the matcher code to evaluate those for a match too, instead
> of only looking at the remote parent devices. This is required when a
> device supports two mode switches in its endpoints, so we can't simply
> register the mode switch with the parent node.
> 
> Signed-off-by: Prashant Malani <pmalani@xxxxxxxxxxxx>
> Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx>

Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
> 
> Changes in v13:
> - Update the kernel doc of fwnode_connection_find_match
> 
> Changes in v12:
> - Check the availability of the device node in fwnode_graph_devcon_matches
> - Ensured valid access to "matches" in fwnode_graph_devcon_matches
> - Updated the documentation in fwnode_connection_find_match(es)
> - Dropped collected tags due to the new changes
> 
> Changes in v11:
> - Added missing fwnode_handle_put in drivers/base/property.c
> 
> Changes in v10:
> - Collected Reviewed-by and Tested-by tags
> 
> Changes in v6:
> - New in v6
> 
>  drivers/base/property.c | 31 ++++++++++++++++++++++++++-----
>  1 file changed, 26 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/base/property.c b/drivers/base/property.c
> index 083a95791d3b..4426ac2b16ca 100644
> --- a/drivers/base/property.c
> +++ b/drivers/base/property.c
> @@ -1243,6 +1243,23 @@ static unsigned int fwnode_graph_devcon_matches(const struct fwnode_handle *fwno
>  			continue;
>  		}
>  
> +		ret = match(node, con_id, data);
> +		fwnode_handle_put(node);
> +		if (ret) {
> +			if (matches)
> +				matches[count] = ret;
> +			count++;
> +
> +			if (matches && count >= matches_len)
> +				break;
> +		}
> +
> +		/*
> +		 * Some drivers may register devices for endpoints. Check
> +		 * the remote-endpoints for matches in addition to the remote
> +		 * port parent.
> +		 */
> +		node = fwnode_graph_get_remote_endpoint(ep);
>  		ret = match(node, con_id, data);
>  		fwnode_handle_put(node);
>  		if (ret) {
> @@ -1293,8 +1310,11 @@ static unsigned int fwnode_devcon_matches(const struct fwnode_handle *fwnode,
>   * @match: Function to check and convert the connection description
>   *
>   * Find a connection with unique identifier @con_id between @fwnode and another
> - * device node. @match will be used to convert the connection description to
> - * data the caller is expecting to be returned.
> + * device node. For fwnode graph connections, the graph endpoints are also
> + * checked. @match will be used to convert the connection description to data
> + * the caller is expecting to be returned.
> + *
> + * Return: The pointer to the matched node, or NULL on error.
>   */
>  void *fwnode_connection_find_match(const struct fwnode_handle *fwnode,
>  				   const char *con_id, void *data,
> @@ -1325,9 +1345,10 @@ EXPORT_SYMBOL_GPL(fwnode_connection_find_match);
>   * @matches_len: Length of @matches
>   *
>   * Find up to @matches_len connections with unique identifier @con_id between
> - * @fwnode and other device nodes. @match will be used to convert the
> - * connection description to data the caller is expecting to be returned
> - * through the @matches array.
> + * @fwnode and other device nodes. For fwnode graph connections, the graph
> + * endpoints are also checked. @match will be used to convert the connection
> + * description to data the caller is expecting to be returned through the
> + * @matches array.
>   * If @matches is NULL @matches_len is ignored and the total number of resolved
>   * matches is returned.
>   *
> -- 
> 2.40.0.rc0.216.gc4246ad0f0-goog

-- 
heikki