1 files changed, 228 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 000000000..83143d39d
--- /dev/null
+++ b/drivers/media/v4l2-core/v4l2-of.c
@@ -0,0 +1,228 @@
+/*
+ * 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 int 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;
+	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;
+		unsigned int i;
+
+		for (i = 0; i < ARRAY_SIZE(bus->data_lanes); i++) {
+			lane = of_prop_next_u32(prop, lane, &v);
+			if (!lane)
+				break;
+			bus->data_lanes[i] = v;
+		}
+		bus->num_data_lanes = i;
+	}
+
+	prop = of_find_property(node, "lane-polarities", NULL);
+	if (prop) {
+		const __be32 *polarity = NULL;
+		unsigned int i;
+
+		for (i = 0; i < ARRAY_SIZE(bus->lane_polarities); i++) {
+			polarity = of_prop_next_u32(prop, polarity, &v);
+			if (!polarity)
+				break;
+			bus->lane_polarities[i] = v;
+		}
+
+		if (i < 1 + bus->num_data_lanes /* clock + data */) {
+			pr_warn("%s: too few lane-polarities entries (need %u, got %u)\n",
+				node->full_name, 1 + bus->num_data_lanes, i);
+			return -EINVAL;
+		}
+	}
+
+	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;
+
+	return 0;
+}
+
+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;
+
+	if (!of_property_read_u32(node, "sync-on-green-active", &v))
+		flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
+			V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;
+
+	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.
+ *
+ * Return: 0.
+ */
+int v4l2_of_parse_endpoint(const struct device_node *node,
+			   struct v4l2_of_endpoint *endpoint)
+{
+	int rval;
+
+	of_graph_parse_endpoint(node, &endpoint->base);
+	endpoint->bus_type = 0;
+	memset(&endpoint->bus, 0, sizeof(endpoint->bus));
+
+	rval = v4l2_of_parse_csi_bus(node, endpoint);
+	if (rval)
+		return rval;
+	/*
+	 * 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);
+
+	return 0;
+}
+EXPORT_SYMBOL(v4l2_of_parse_endpoint);
+
+/**
+ * v4l2_of_parse_link() - parse a link between two endpoints
+ * @node: pointer to the endpoint at the local end of the link
+ * @link: pointer to the V4L2 OF link data structure
+ *
+ * Fill the link structure with the local and remote nodes and port numbers.
+ * The local_node and remote_node fields are set to point to the local and
+ * remote port's parent nodes respectively (the port parent node being the
+ * parent node of the port node if that node isn't a 'ports' node, or the
+ * grand-parent node of the port node otherwise).
+ *
+ * A reference is taken to both the local and remote nodes, the caller must use
+ * v4l2_of_put_link() to drop the references when done with the link.
+ *
+ * Return: 0 on success, or -ENOLINK if the remote endpoint can't be found.
+ */
+int v4l2_of_parse_link(const struct device_node *node,
+		       struct v4l2_of_link *link)
+{
+	struct device_node *np;
+
+	memset(link, 0, sizeof(*link));
+
+	np = of_get_parent(node);
+	of_property_read_u32(np, "reg", &link->local_port);
+	np = of_get_next_parent(np);
+	if (of_node_cmp(np->name, "ports") == 0)
+		np = of_get_next_parent(np);
+	link->local_node = np;
+
+	np = of_parse_phandle(node, "remote-endpoint", 0);
+	if (!np) {
+		of_node_put(link->local_node);
+		return -ENOLINK;
+	}
+
+	np = of_get_parent(np);
+	of_property_read_u32(np, "reg", &link->remote_port);
+	np = of_get_next_parent(np);
+	if (of_node_cmp(np->name, "ports") == 0)
+		np = of_get_next_parent(np);
+	link->remote_node = np;
+
+	return 0;
+}
+EXPORT_SYMBOL(v4l2_of_parse_link);
+
+/**
+ * v4l2_of_put_link() - drop references to nodes in a link
+ * @link: pointer to the V4L2 OF link data structure
+ *
+ * Drop references to the local and remote nodes in the link. This function must
+ * be called on every link parsed with v4l2_of_parse_link().
+ */
+void v4l2_of_put_link(struct v4l2_of_link *link)
+{
+	of_node_put(link->local_node);
+	of_node_put(link->remote_node);
+}
+EXPORT_SYMBOL(v4l2_of_put_link);