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

From: Pin-yen Lin
Date: Fri Mar 03 2023 - 09:34:29 EST


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>

---

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