1/*
  2 * V4L2 OF binding parsing library
  3 *
  4 * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
  5 * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
  6 *
  7 * Copyright (C) 2012 Renesas Electronics Corp.
  8 * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
  9 *
 10 * This program is free software; you can redistribute it and/or modify
 11 * it under the terms of version 2 of the GNU General Public License as
 12 * published by the Free Software Foundation.
 13 */
 14#include <linux/kernel.h>
 15#include <linux/module.h>
 16#include <linux/of.h>
 17#include <linux/string.h>
 18#include <linux/types.h>
 19
 20#include <media/v4l2-of.h>
 21
 22static void v4l2_of_parse_csi_bus(const struct device_node *node,
 23				  struct v4l2_of_endpoint *endpoint)
 24{
 25	struct v4l2_of_bus_mipi_csi2 *bus = &endpoint->bus.mipi_csi2;
 26	u32 data_lanes[ARRAY_SIZE(bus->data_lanes)];
 27	struct property *prop;
 28	bool have_clk_lane = false;
 29	unsigned int flags = 0;
 30	u32 v;
 31
 32	prop = of_find_property(node, "data-lanes", NULL);
 33	if (prop) {
 34		const __be32 *lane = NULL;
 35		int i;
 36
 37		for (i = 0; i < ARRAY_SIZE(data_lanes); i++) {
 38			lane = of_prop_next_u32(prop, lane, &data_lanes[i]);
 39			if (!lane)
 40				break;
 41		}
 42		bus->num_data_lanes = i;
 43		while (i--)
 44			bus->data_lanes[i] = data_lanes[i];
 45	}
 46
 47	if (!of_property_read_u32(node, "clock-lanes", &v)) {
 48		bus->clock_lane = v;
 49		have_clk_lane = true;
 50	}
 51
 52	if (of_get_property(node, "clock-noncontinuous", &v))
 53		flags |= V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
 54	else if (have_clk_lane || bus->num_data_lanes > 0)
 55		flags |= V4L2_MBUS_CSI2_CONTINUOUS_CLOCK;
 56
 57	bus->flags = flags;
 58	endpoint->bus_type = V4L2_MBUS_CSI2;
 59}
 60
 61static void v4l2_of_parse_parallel_bus(const struct device_node *node,
 62				       struct v4l2_of_endpoint *endpoint)
 63{
 64	struct v4l2_of_bus_parallel *bus = &endpoint->bus.parallel;
 65	unsigned int flags = 0;
 66	u32 v;
 67
 68	if (!of_property_read_u32(node, "hsync-active", &v))
 69		flags |= v ? V4L2_MBUS_HSYNC_ACTIVE_HIGH :
 70			V4L2_MBUS_HSYNC_ACTIVE_LOW;
 71
 72	if (!of_property_read_u32(node, "vsync-active", &v))
 73		flags |= v ? V4L2_MBUS_VSYNC_ACTIVE_HIGH :
 74			V4L2_MBUS_VSYNC_ACTIVE_LOW;
 75
 76	if (!of_property_read_u32(node, "pclk-sample", &v))
 77		flags |= v ? V4L2_MBUS_PCLK_SAMPLE_RISING :
 78			V4L2_MBUS_PCLK_SAMPLE_FALLING;
 79
 80	if (!of_property_read_u32(node, "field-even-active", &v))
 81		flags |= v ? V4L2_MBUS_FIELD_EVEN_HIGH :
 82			V4L2_MBUS_FIELD_EVEN_LOW;
 83	if (flags)
 84		endpoint->bus_type = V4L2_MBUS_PARALLEL;
 85	else
 86		endpoint->bus_type = V4L2_MBUS_BT656;
 87
 88	if (!of_property_read_u32(node, "data-active", &v))
 89		flags |= v ? V4L2_MBUS_DATA_ACTIVE_HIGH :
 90			V4L2_MBUS_DATA_ACTIVE_LOW;
 91
 92	if (of_get_property(node, "slave-mode", &v))
 93		flags |= V4L2_MBUS_SLAVE;
 94	else
 95		flags |= V4L2_MBUS_MASTER;
 96
 97	if (!of_property_read_u32(node, "bus-width", &v))
 98		bus->bus_width = v;
 99
100	if (!of_property_read_u32(node, "data-shift", &v))
101		bus->data_shift = v;
102
103	if (!of_property_read_u32(node, "sync-on-green-active", &v))
104		flags |= v ? V4L2_MBUS_VIDEO_SOG_ACTIVE_HIGH :
105			V4L2_MBUS_VIDEO_SOG_ACTIVE_LOW;
106
107	bus->flags = flags;
108
109}
110
111/**
112 * v4l2_of_parse_endpoint() - parse all endpoint node properties
113 * @node: pointer to endpoint device_node
114 * @endpoint: pointer to the V4L2 OF endpoint data structure
115 *
116 * All properties are optional. If none are found, we don't set any flags.
117 * This means the port has a static configuration and no properties have
118 * to be specified explicitly.
119 * If any properties that identify the bus as parallel are found and
120 * slave-mode isn't set, we set V4L2_MBUS_MASTER. Similarly, if we recognise
121 * the bus as serial CSI-2 and clock-noncontinuous isn't set, we set the
122 * V4L2_MBUS_CSI2_CONTINUOUS_CLOCK flag.
123 * The caller should hold a reference to @node.
124 *
125 * Return: 0.
126 */
127int v4l2_of_parse_endpoint(const struct device_node *node,
128			   struct v4l2_of_endpoint *endpoint)
129{
130	of_graph_parse_endpoint(node, &endpoint->base);
131	endpoint->bus_type = 0;
132	memset(&endpoint->bus, 0, sizeof(endpoint->bus));
133
134	v4l2_of_parse_csi_bus(node, endpoint);
135	/*
136	 * Parse the parallel video bus properties only if none
137	 * of the MIPI CSI-2 specific properties were found.
138	 */
139	if (endpoint->bus.mipi_csi2.flags == 0)
140		v4l2_of_parse_parallel_bus(node, endpoint);
141
142	return 0;
143}
144EXPORT_SYMBOL(v4l2_of_parse_endpoint);