aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/bus/vexpress-config.c
blob: 493e7b9fc81357bc7366539cc4a8eaf22413be7f (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
/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Copyright (C) 2014 ARM Limited
 */

#include <linux/err.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/vexpress.h>


struct vexpress_config_bridge {
	struct vexpress_config_bridge_ops *ops;
	void *context;
};


static DEFINE_MUTEX(vexpress_config_mutex);
static struct class *vexpress_config_class;
static u32 vexpress_config_site_master = VEXPRESS_SITE_MASTER;


void vexpress_config_set_master(u32 site)
{
	vexpress_config_site_master = site;
}

u32 vexpress_config_get_master(void)
{
	return vexpress_config_site_master;
}

void vexpress_config_lock(void *arg)
{
	mutex_lock(&vexpress_config_mutex);
}

void vexpress_config_unlock(void *arg)
{
	mutex_unlock(&vexpress_config_mutex);
}


static void vexpress_config_find_prop(struct device_node *node,
		const char *name, u32 *val)
{
	/* Default value */
	*val = 0;

	of_node_get(node);
	while (node) {
		if (of_property_read_u32(node, name, val) == 0) {
			of_node_put(node);
			return;
		}
		node = of_get_next_parent(node);
	}
}

int vexpress_config_get_topo(struct device_node *node, u32 *site,
		u32 *position, u32 *dcc)
{
	vexpress_config_find_prop(node, "arm,vexpress,site", site);
	if (*site == VEXPRESS_SITE_MASTER)
		*site = vexpress_config_site_master;
	if (WARN_ON(vexpress_config_site_master == VEXPRESS_SITE_MASTER))
		return -EINVAL;
	vexpress_config_find_prop(node, "arm,vexpress,position", position);
	vexpress_config_find_prop(node, "arm,vexpress,dcc", dcc);

	return 0;
}


static void vexpress_config_devres_release(struct device *dev, void *res)
{
	struct vexpress_config_bridge *bridge = dev_get_drvdata(dev->parent);
	struct regmap *regmap = res;

	bridge->ops->regmap_exit(regmap, bridge->context);
}

struct regmap *devm_regmap_init_vexpress_config(struct device *dev)
{
	struct vexpress_config_bridge *bridge;
	struct regmap *regmap;
	struct regmap **res;

	if (WARN_ON(dev->parent->class != vexpress_config_class))
		return ERR_PTR(-ENODEV);

	bridge = dev_get_drvdata(dev->parent);
	if (WARN_ON(!bridge))
		return ERR_PTR(-EINVAL);

	res = devres_alloc(vexpress_config_devres_release, sizeof(*res),
			GFP_KERNEL);
	if (!res)
		return ERR_PTR(-ENOMEM);

	regmap = (bridge->ops->regmap_init)(dev, bridge->context);
	if (IS_ERR(regmap)) {
		devres_free(res);
		return regmap;
	}

	*res = regmap;
	devres_add(dev, res);

	return regmap;
}
EXPORT_SYMBOL_GPL(devm_regmap_init_vexpress_config);

struct device *vexpress_config_bridge_register(struct device *parent,
		struct vexpress_config_bridge_ops *ops, void *context)
{
	struct device *dev;
	struct vexpress_config_bridge *bridge;

	if (!vexpress_config_class) {
		vexpress_config_class = class_create(THIS_MODULE,
				"vexpress-config");
		if (IS_ERR(vexpress_config_class))
			return (void *)vexpress_config_class;
	}

	dev = device_create(vexpress_config_class, parent, 0,
			NULL, "%s.bridge", dev_name(parent));

	if (IS_ERR(dev))
		return dev;

	bridge = devm_kmalloc(dev, sizeof(*bridge), GFP_KERNEL);
	if (!bridge) {
		put_device(dev);
		device_unregister(dev);
		return ERR_PTR(-ENOMEM);
	}
	bridge->ops = ops;
	bridge->context = context;

	dev_set_drvdata(dev, bridge);

	dev_dbg(parent, "Registered bridge '%s', parent node %p\n",
			dev_name(dev), parent->of_node);

	return dev;
}


static int vexpress_config_node_match(struct device *dev, const void *data)
{
	const struct device_node *node = data;

	dev_dbg(dev, "Parent node %p, looking for %p\n",
			dev->parent->of_node, node);

	return dev->parent->of_node == node;
}

static int vexpress_config_populate(struct device_node *node)
{
	struct device_node *bridge;
	struct device *parent;
	int ret;

	bridge = of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
	if (!bridge)
		return -EINVAL;

	parent = class_find_device(vexpress_config_class, NULL, bridge,
			vexpress_config_node_match);
	of_node_put(bridge);
	if (WARN_ON(!parent))
		return -ENODEV;

	ret = of_platform_populate(node, NULL, NULL, parent);

	put_device(parent);

	return ret;
}

static int __init vexpress_config_init(void)
{
	int err = 0;
	struct device_node *node;

	/* Need the config devices early, before the "normal" devices... */
	for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") {
		err = vexpress_config_populate(node);
		if (err) {
			of_node_put(node);
			break;
		}
	}

	return err;
}
postcore_initcall(vexpress_config_init);

Privacy Policy