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author | Philipp Zabel <p.zabel@pengutronix.de> | 2014-02-10 22:01:48 +0100 |
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committer | Philipp Zabel <p.zabel@pengutronix.de> | 2014-03-06 17:41:22 +0100 |
commit | fd9fdb78a9bf85b94fb2190c82ff280c8f8375cc (patch) | |
tree | 49ad197ab19b401edbc4957b5ce2ed53af643b09 /drivers/of/base.c | |
parent | Linux 3.14-rc5 (diff) | |
download | linux-fd9fdb78a9bf85b94fb2190c82ff280c8f8375cc.tar.xz linux-fd9fdb78a9bf85b94fb2190c82ff280c8f8375cc.zip |
[media] of: move graph helpers from drivers/media/v4l2-core to drivers/of
This patch moves the parsing helpers used to parse connected graphs
in the device tree, like the video interface bindings documented in
Documentation/devicetree/bindings/media/video-interfaces.txt, from
drivers/media/v4l2-core/v4l2-of.c into drivers/of/base.c.
This allows to reuse the same parser code from outside the V4L2
framework, most importantly from display drivers.
The functions v4l2_of_get_next_endpoint, v4l2_of_get_remote_port,
and v4l2_of_get_remote_port_parent are moved. They are renamed to
of_graph_get_next_endpoint, of_graph_get_remote_port, and
of_graph_get_remote_port_parent, respectively.
Since there are not that many current users yet, switch all of
them to the new functions right away.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Diffstat (limited to 'drivers/of/base.c')
-rw-r--r-- | drivers/of/base.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c index 89e888a78899..b2f223fa47e9 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -21,6 +21,7 @@ #include <linux/cpu.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/of_graph.h> #include <linux/spinlock.h> #include <linux/slab.h> #include <linux/proc_fs.h> @@ -1982,3 +1983,120 @@ struct device_node *of_find_next_cache_node(const struct device_node *np) return NULL; } + +/** + * of_graph_get_next_endpoint() - get next endpoint node + * @parent: pointer to the parent device node + * @prev: previous endpoint node, or NULL to get first + * + * Return: An 'endpoint' node pointer with refcount incremented. Refcount + * of the passed @prev node is not decremented, the caller have to use + * of_node_put() on it when done. + */ +struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, + struct device_node *prev) +{ + struct device_node *endpoint; + struct device_node *port = NULL; + + if (!parent) + return NULL; + + 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"); + + 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", + __func__, parent->full_name); + of_node_put(node); + } else { + port = of_get_parent(prev); + if (!port) + /* Hm, has someone given us the root node ?... */ + return NULL; + + /* Avoid dropping prev node refcount to 0. */ + of_node_get(prev); + endpoint = of_get_next_child(port, prev); + if (endpoint) { + of_node_put(port); + return endpoint; + } + + /* No more endpoints under this port, try the next one. */ + 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(of_graph_get_next_endpoint); + +/** + * of_graph_get_remote_port_parent() - get remote port's parent node + * @node: pointer to a local endpoint device_node + * + * Return: Remote device node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_port_parent( + const struct device_node *node) +{ + struct device_node *np; + unsigned int depth; + + /* Get remote endpoint node. */ + np = of_parse_phandle(node, "remote-endpoint", 0); + + /* Walk 3 levels up only if there is 'ports' node. */ + for (depth = 3; depth && np; depth--) { + np = of_get_next_parent(np); + if (depth == 2 && of_node_cmp(np->name, "ports")) + break; + } + return np; +} +EXPORT_SYMBOL(of_graph_get_remote_port_parent); + +/** + * of_graph_get_remote_port() - get remote port node + * @node: pointer to a local endpoint device_node + * + * Return: Remote port node associated with remote endpoint node linked + * to @node. Use of_node_put() on it when done. + */ +struct device_node *of_graph_get_remote_port(const struct device_node *node) +{ + struct device_node *np; + + /* Get remote endpoint node. */ + np = of_parse_phandle(node, "remote-endpoint", 0); + if (!np) + return NULL; + return of_get_next_parent(np); +} +EXPORT_SYMBOL(of_graph_get_remote_port); |