kernel-ark/arch/powerpc/kernel/of_device.c
Sylvain Munaut de41189bf6 [POWERPC] Export of_device_get_modalias
Apparently other parts of the kernel need to know the
modalias internally (like the sysfs code in macintosh driver).

To avoid consistency issues, we export this code and use it
everywhere it's needed rather than repeat it ...

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-05-07 20:31:15 +10:00

243 lines
5.5 KiB
C

#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <asm/errno.h>
#include <asm/of_device.h>
/**
* of_match_node - Tell if an device_node has a matching of_match structure
* @ids: array of of device match structures to search in
* @node: the of device structure to match against
*
* Low level utility function used by device matching.
*/
const struct of_device_id *of_match_node(const struct of_device_id *matches,
const struct device_node *node)
{
while (matches->name[0] || matches->type[0] || matches->compatible[0]) {
int match = 1;
if (matches->name[0])
match &= node->name
&& !strcmp(matches->name, node->name);
if (matches->type[0])
match &= node->type
&& !strcmp(matches->type, node->type);
if (matches->compatible[0])
match &= of_device_is_compatible(node,
matches->compatible);
if (match)
return matches;
matches++;
}
return NULL;
}
/**
* of_match_device - Tell if an of_device structure has a matching
* of_match structure
* @ids: array of of device match structures to search in
* @dev: the of device structure to match against
*
* Used by a driver to check whether an of_device present in the
* system is in its list of supported devices.
*/
const struct of_device_id *of_match_device(const struct of_device_id *matches,
const struct of_device *dev)
{
if (!dev->node)
return NULL;
return of_match_node(matches, dev->node);
}
struct of_device *of_dev_get(struct of_device *dev)
{
struct device *tmp;
if (!dev)
return NULL;
tmp = get_device(&dev->dev);
if (tmp)
return to_of_device(tmp);
else
return NULL;
}
void of_dev_put(struct of_device *dev)
{
if (dev)
put_device(&dev->dev);
}
static ssize_t dev_show_devspec(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct of_device *ofdev;
ofdev = to_of_device(dev);
return sprintf(buf, "%s", ofdev->node->full_name);
}
static DEVICE_ATTR(devspec, S_IRUGO, dev_show_devspec, NULL);
/**
* of_release_dev - free an of device structure when all users of it are finished.
* @dev: device that's been disconnected
*
* Will be called only by the device core when all users of this of device are
* done.
*/
void of_release_dev(struct device *dev)
{
struct of_device *ofdev;
ofdev = to_of_device(dev);
of_node_put(ofdev->node);
kfree(ofdev);
}
int of_device_register(struct of_device *ofdev)
{
int rc;
BUG_ON(ofdev->node == NULL);
rc = device_register(&ofdev->dev);
if (rc)
return rc;
return device_create_file(&ofdev->dev, &dev_attr_devspec);
}
void of_device_unregister(struct of_device *ofdev)
{
device_remove_file(&ofdev->dev, &dev_attr_devspec);
device_unregister(&ofdev->dev);
}
ssize_t of_device_get_modalias(struct of_device *ofdev,
char *str, ssize_t len)
{
const char *compat;
int cplen, i;
ssize_t tsize, csize, repend;
/* Name & Type */
csize = snprintf(str, len, "of:N%sT%s",
ofdev->node->name, ofdev->node->type);
/* Get compatible property if any */
compat = of_get_property(ofdev->node, "compatible", &cplen);
if (!compat)
return csize;
/* Find true end (we tolerate multiple \0 at the end */
for (i=(cplen-1); i>=0 && !compat[i]; i--)
cplen--;
if (!cplen)
return csize;
cplen++;
/* Check space (need cplen+1 chars including final \0) */
tsize = csize + cplen;
repend = tsize;
if (csize>=len) /* @ the limit, all is already filled */
return tsize;
if (tsize>=len) { /* limit compat list */
cplen = len-csize-1;
repend = len;
}
/* Copy and do char replacement */
memcpy(&str[csize+1], compat, cplen);
for (i=csize; i<repend; i++) {
char c = str[i];
if (c=='\0')
str[i] = 'C';
else if (c==' ')
str[i] = '_';
}
return tsize;
}
int of_device_uevent(struct device *dev,
char **envp, int num_envp, char *buffer, int buffer_size)
{
struct of_device *ofdev;
const char *compat;
int i = 0, length = 0, seen = 0, cplen, sl;
if (!dev)
return -ENODEV;
ofdev = to_of_device(dev);
if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
"OF_NAME=%s", ofdev->node->name))
return -ENOMEM;
if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
"OF_TYPE=%s", ofdev->node->type))
return -ENOMEM;
/* Since the compatible field can contain pretty much anything
* it's not really legal to split it out with commas. We split it
* up using a number of environment variables instead. */
compat = of_get_property(ofdev->node, "compatible", &cplen);
while (compat && *compat && cplen > 0) {
if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
"OF_COMPATIBLE_%d=%s", seen, compat))
return -ENOMEM;
sl = strlen (compat) + 1;
compat += sl;
cplen -= sl;
seen++;
}
if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
"OF_COMPATIBLE_N=%d", seen))
return -ENOMEM;
/* modalias is trickier, we add it in 2 steps */
if (add_uevent_var(envp, num_envp, &i,
buffer, buffer_size, &length,
"MODALIAS="))
return -ENOMEM;
sl = of_device_get_modalias(ofdev, &buffer[length-1],
buffer_size-length);
if (sl >= (buffer_size-length))
return -ENOMEM;
length += sl;
envp[i] = NULL;
return 0;
}
EXPORT_SYMBOL(of_match_node);
EXPORT_SYMBOL(of_match_device);
EXPORT_SYMBOL(of_device_register);
EXPORT_SYMBOL(of_device_unregister);
EXPORT_SYMBOL(of_dev_get);
EXPORT_SYMBOL(of_dev_put);
EXPORT_SYMBOL(of_release_dev);
EXPORT_SYMBOL(of_device_uevent);
EXPORT_SYMBOL(of_device_get_modalias);