summaryrefslogtreecommitdiffstats
path: root/drivers/media/v4l2-core/v4l2-of.c
blob: 83143d39dea760d1120f6bf7d2fa309a147a2189 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
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);