[v2,01/48] v4l: of: Support empty port nodes
Commit Message
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 <laurent.pinchart@ideasonboard.com>
---
drivers/media/v4l2-core/v4l2-of.c | 52 +++++++++++++++++++++------------------
1 file changed, 28 insertions(+), 24 deletions(-)
Comments
Hi Laurent,
On 11/03/14 00:15, Laurent Pinchart wrote:
> 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 <laurent.pinchart@ideasonboard.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
> ---
> 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 42e3e8a..4c07343 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);
>
@@ -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);