1#include <linux/string.h>
  2#include <linux/kernel.h>
  3#include <linux/of.h>
  4#include <linux/of_device.h>
  5#include <linux/init.h>
  6#include <linux/module.h>
  7#include <linux/mod_devicetable.h>
  8#include <linux/slab.h>
  9
 10#include <asm/errno.h>
 11
 12/**
 13 * of_match_device - Tell if a struct device matches an of_device_id list
 14 * @ids: array of of device match structures to search in
 15 * @dev: the of device structure to match against
 16 *
 17 * Used by a driver to check whether an platform_device present in the
 18 * system is in its list of supported devices.
 19 */
 20const struct of_device_id *of_match_device(const struct of_device_id *matches,
 21					   const struct device *dev)
 22{
 23	if ((!matches) || (!dev->of_node))
 24		return NULL;
 25	return of_match_node(matches, dev->of_node);
 26}
 27EXPORT_SYMBOL(of_match_device);
 28
 29struct platform_device *of_dev_get(struct platform_device *dev)
 30{
 31	struct device *tmp;
 32
 33	if (!dev)
 34		return NULL;
 35	tmp = get_device(&dev->dev);
 36	if (tmp)
 37		return to_platform_device(tmp);
 38	else
 39		return NULL;
 40}
 41EXPORT_SYMBOL(of_dev_get);
 42
 43void of_dev_put(struct platform_device *dev)
 44{
 45	if (dev)
 46		put_device(&dev->dev);
 47}
 48EXPORT_SYMBOL(of_dev_put);
 49
 50int of_device_add(struct platform_device *ofdev)
 51{
 52	BUG_ON(ofdev->dev.of_node == NULL);
 53
 54	/* name and id have to be set so that the platform bus doesn't get
 55	 * confused on matching */
 56	ofdev->name = dev_name(&ofdev->dev);
 57	ofdev->id = -1;
 58
 59	/* device_add will assume that this device is on the same node as
 60	 * the parent. If there is no parent defined, set the node
 61	 * explicitly */
 62	if (!ofdev->dev.parent)
 63		set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
 64
 65	return device_add(&ofdev->dev);
 66}
 67
 68int of_device_register(struct platform_device *pdev)
 69{
 70	device_initialize(&pdev->dev);
 71	return of_device_add(pdev);
 72}
 73EXPORT_SYMBOL(of_device_register);
 74
 75void of_device_unregister(struct platform_device *ofdev)
 76{
 77	device_unregister(&ofdev->dev);
 78}
 79EXPORT_SYMBOL(of_device_unregister);
 80
 81ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
 82{
 83	const char *compat;
 84	int cplen, i;
 85	ssize_t tsize, csize, repend;
 86
 87	/* Name & Type */
 88	csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name,
 89			 dev->of_node->type);
 90
 91	/* Get compatible property if any */
 92	compat = of_get_property(dev->of_node, "compatible", &cplen);
 93	if (!compat)
 94		return csize;
 95
 96	/* Find true end (we tolerate multiple \0 at the end */
 97	for (i = (cplen - 1); i >= 0 && !compat[i]; i--)
 98		cplen--;
 99	if (!cplen)
100		return csize;
101	cplen++;
102
103	/* Check space (need cplen+1 chars including final \0) */
104	tsize = csize + cplen;
105	repend = tsize;
106
107	if (csize >= len)		/* @ the limit, all is already filled */
108		return tsize;
109
110	if (tsize >= len) {		/* limit compat list */
111		cplen = len - csize - 1;
112		repend = len;
113	}
114
115	/* Copy and do char replacement */
116	memcpy(&str[csize + 1], compat, cplen);
117	for (i = csize; i < repend; i++) {
118		char c = str[i];
119		if (c == '\0')
120			str[i] = 'C';
121		else if (c == ' ')
122			str[i] = '_';
123	}
124
125	return tsize;
126}
127
128/**
129 * of_device_uevent - Display OF related uevent information
130 */
131void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
132{
133	const char *compat;
134	int seen = 0, cplen, sl;
135
136	if ((!dev) || (!dev->of_node))
137		return;
138
139	add_uevent_var(env, "OF_NAME=%s", dev->of_node->name);
140	add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name);
141	if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0)
142		add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type);
143
144	/* Since the compatible field can contain pretty much anything
145	 * it's not really legal to split it out with commas. We split it
146	 * up using a number of environment variables instead. */
147	compat = of_get_property(dev->of_node, "compatible", &cplen);
148	while (compat && *compat && cplen > 0) {
149		add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
150		sl = strlen(compat) + 1;
151		compat += sl;
152		cplen -= sl;
153		seen++;
154	}
155	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
156}
157
158int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
159{
160	int sl;
161
162	if ((!dev) || (!dev->of_node))
163		return -ENODEV;
164
165	/* Devicetree modalias is tricky, we add it in 2 steps */
166	if (add_uevent_var(env, "MODALIAS="))
167		return -ENOMEM;
168
169	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
170				    sizeof(env->buf) - env->buflen);
171	if (sl >= (sizeof(env->buf) - env->buflen))
172		return -ENOMEM;
173	env->buflen += sl;
174
175	return 0;
176}