1 files changed, 266 insertions, 0 deletions

diff --git a/drivers/media/v4l2-core/v4l2-of.c b/drivers/media/v4l2-core/v4l2-of.c
new file mode 100644
index 000000000000..aa59639d013c
--- /dev/null
+++ b/drivers/media/v4l2-core/v4l2-of.c
@@ -0,0 +1,266 @@
+/*
+ * V4L2 OF binding parsing library
+ *
+ * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
+ * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
+ *
+ * Copyright (C) 2012 Renesas Electronics Corp.
+ * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <media/v4l2-of.h>
+
+static void v4l2_of_parse_csi_bus(const struct device_node *node,
+                                  struct v4l2_of_endpoint *endpoint)
+{
+        struct v4l2_of_bus_mipi_csi2 *bus = &endpoint->bus.mipi_csi2;
+        u32 data_lanes[ARRAY_SIZE(bus->data_lanes)];
+        struct property *prop;
+        bool have_clk_lane = false;
+        unsigned int flags = 0;
+        u32 v;
+
+        prop = of_find_property(node, "data-lanes", NULL);
+        if (prop) {
+                const __be32 *lane = NULL;
+                int i;
+
+                for (i = 0; i < ARRAY_SIZE(data_lanes); i++) {
+                        lane = of_prop_next_u32(prop, lane, &data_lanes[i]);
+                        if (!lane)
+                                break;
+                }
+                bus->num_data_lanes = i;
+                while (i--)
+                        bus->data_lanes[i] = data_lanes[i];
+        }
+
+        if (!of_property_read_u32(node, "clock-lanes", &v)) {
+                bus->clock_lane = v;
+                have_clk_lane = true;
+        }
+
+        if (of_get_property(node, "clock-noncontinuous", &v))
+                flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
+        else if (have_clk_lane || bus->num_data_lanes > 0)
+                flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK;
+
+        bus->flags = flags;
+        endpoint->bus_type = V4L2_MBUS_CSI2;
+}
+
+static void v4l2_of_parse_parallel_bus(const struct device_node *node,
+                                       struct v4l2_of_endpoint *endpoint)
+{
+        struct v4l2_of_bus_parallel *bus = &endpoint->bus.parallel;
+        unsigned int flags = 0;
+        u32 v;
+
+        if (!of_property_read_u32(node, "hsync-active", &v))
+                flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH :
+                        V4L2_MBUS_HSYNC_ACTIVE_LOW;
+
+        if (!of_property_read_u32(node, "vsync-active", &v))
+                flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH :
+                        V4L2_MBUS_VSYNC_ACTIVE_LOW;
+
+        if (!of_property_read_u32(node, "pclk-sample", &v))
+                flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING :
+                        V4L2_MBUS_PCLK_SAMPLE_FALLING;
+
+        if (!of_property_read_u32(node, "field-even-active", &v))
+                flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
+                        V4L2_MBUS_FIELD_EVEN_LOW;
+        if (flags)
+                endpoint->bus_type = V4L2_MBUS_PARALLEL;
+        else
+                endpoint->bus_type = V4L2_MBUS_BT656;
+
+        if (!of_property_read_u32(node, "data-active", &v))
+                flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH :
+                        V4L2_MBUS_DATA_ACTIVE_LOW;
+
+        if (of_get_property(node, "slave-mode", &v))
+                flags |= V4L2_MBUS_SLAVE;
+        else
+                flags |= V4L2_MBUS_MASTER;
+
+        if (!of_property_read_u32(node, "bus-width", &v))
+                bus->bus_width = v;
+
+        if (!of_property_read_u32(node, "data-shift", &v))
+                bus->data_shift = v;
+
+        bus->flags = flags;
+
+}
+
+/**
+ * v4l2_of_parse_endpoint() - parse all endpoint node properties
+ * @node: pointer to endpoint device_node
+ * @endpoint: pointer to the V4L2 OF endpoint data structure
+ *
+ * All properties are optional. If none are found, we don't set any flags.
+ * This means the port has a static configuration and no properties have
+ * to be specified explicitly.
+ * If any properties that identify the bus as parallel are found and
+ * slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if we recognise
+ * the bus as serial CSI-2 and clock-noncontinuous isn't set, we set the
+ * V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag.
+ * The caller should hold a reference to @node.
+ */
+void v4l2_of_parse_endpoint(const struct device_node *node,
+                            struct v4l2_of_endpoint *endpoint)
+{
+        struct device_node *port_node = of_get_parent(node);
+
+        memset(endpoint, 0, offsetof(struct v4l2_of_endpoint, head));
+
+        endpoint->local_node = node;
+        /*
+         * It doesn't matter whether the two calls below succeed.
+         * If they don't then the default value 0 is used.
+         */
+        of_property_read_u32(port_node, "reg", &endpoint->port);
+        of_property_read_u32(node, "reg", &endpoint->id);
+
+        v4l2_of_parse_csi_bus(node, endpoint);
+        /*
+         * Parse the parallel video bus properties only if none
+         * of the MIPI CSI-2 specific properties were found.
+         */
+        if (endpoint->bus.mipi_csi2.flags == 0)
+                v4l2_of_parse_parallel_bus(node, endpoint);
+
+        of_node_put(port_node);
+}
+EXPORT_SYMBOL(v4l2_of_parse_endpoint);
+
+/**
+ * v4l2_of_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 *v4l2_of_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;
+
+                for_each_child_of_node(parent, node) {
+                        if (!of_node_cmp(node->name, "port")) {
+                                port = node;
+                                break;
+                        }
+                }
+                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);
+        } 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(v4l2_of_get_next_endpoint);
+
+/**
+ * v4l2_of_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 *v4l2_of_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(v4l2_of_get_remote_port_parent);
+
+/**
+ * v4l2_of_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 *v4l2_of_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_parent(np);
+}
+EXPORT_SYMBOL(v4l2_of_get_remote_port);