From b9db140c1e4644dc93900db476546e119dce5a28 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Mon, 10 Mar 2014 20:15:12 -0300 Subject: [PATCH] [media] v4l: of: Support empty port nodes Empty port nodes are allowed but currently unsupported as the v4l2_of_get_next_endpoint() function assumes that all port nodes have at least an endpoint. Fix this. Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-of.c | 52 +++++++++++++++++-------------- 1 file changed, 28 insertions(+), 24 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-of.c b/drivers/media/v4l2-core/v4l2-of.c index 42e3e8a5e361..4c073438511a 100644 --- a/drivers/media/v4l2-core/v4l2-of.c +++ b/drivers/media/v4l2-core/v4l2-of.c @@ -166,43 +166,51 @@ struct device_node *v4l2_of_get_next_endpoint(const struct device_node *parent, struct device_node *prev) { struct device_node *endpoint; - struct device_node *port = NULL; + struct device_node *port; if (!parent) return NULL; + /* + * Start by locating the port node. If no previous endpoint is specified + * search for the first port node, otherwise get the previous endpoint + * parent port node. + */ if (!prev) { struct device_node *node; - /* - * It's the first call, we have to find a port subnode - * within this node or within an optional 'ports' node. - */ + node = of_get_child_by_name(parent, "ports"); if (node) parent = node; port = of_get_child_by_name(parent, "port"); + of_node_put(node); - if (port) { - /* Found a port, get an endpoint. */ - endpoint = of_get_next_child(port, NULL); - of_node_put(port); - } else { - endpoint = NULL; - } - - if (!endpoint) - pr_err("%s(): no endpoint nodes specified for %s\n", + if (!port) { + pr_err("%s(): no port node found in %s\n", __func__, parent->full_name); - of_node_put(node); + return NULL; + } } else { port = of_get_parent(prev); - if (!port) + if (!port) { /* Hm, has someone given us the root node ?... */ return NULL; + } - /* Avoid dropping prev node refcount to 0. */ + /* + * Avoid dropping prev node refcount to 0 when getting the next + * child below. + */ of_node_get(prev); + } + + while (1) { + /* + * Now that we have a port node, get the next endpoint by + * getting the next child. If the previous endpoint is NULL this + * will return the first child. + */ endpoint = of_get_next_child(port, prev); if (endpoint) { of_node_put(port); @@ -210,18 +218,14 @@ struct device_node *v4l2_of_get_next_endpoint(const struct device_node *parent, } /* No more endpoints under this port, try the next one. */ + prev = NULL; + do { port = of_get_next_child(parent, port); if (!port) return NULL; } while (of_node_cmp(port->name, "port")); - - /* Pick up the first endpoint in this port. */ - endpoint = of_get_next_child(port, NULL); - of_node_put(port); } - - return endpoint; } EXPORT_SYMBOL(v4l2_of_get_next_endpoint); -- 2.30.2