Driver core: make uevent-environment available in uevent-file

[linux-2.6-omap-h63xx.git] / drivers / base / core.c

diff --git a/drivers/base/core.c b/drivers/base/core.c
index c34a4d8842e12c1fb911c405b290637876a6ce92..72c6ee57471b7f5ee344eb3c5d2132576ca6e676 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -246,6 +246,53 @@ static struct kset_uevent_ops device_uevent_ops = {
        .uevent =       dev_uevent,
 };
 
+static ssize_t show_uevent(struct device *dev, struct device_attribute *attr,
+                          char *buf)
+{
+       struct kobject *top_kobj;
+       struct kset *kset;
+       char *envp[32];
+       char data[PAGE_SIZE];
+       char *pos;
+       int i;
+       size_t count = 0;
+       int retval;
+
+       /* search the kset, the device belongs to */
+       top_kobj = &dev->kobj;
+       if (!top_kobj->kset && top_kobj->parent) {
+               do {
+                       top_kobj = top_kobj->parent;
+               } while (!top_kobj->kset && top_kobj->parent);
+       }
+       if (!top_kobj->kset)
+               goto out;
+       kset = top_kobj->kset;
+       if (!kset->uevent_ops || !kset->uevent_ops->uevent)
+               goto out;
+
+       /* respect filter */
+       if (kset->uevent_ops && kset->uevent_ops->filter)
+               if (!kset->uevent_ops->filter(kset, &dev->kobj))
+                       goto out;
+
+       /* let the kset specific function add its keys */
+       pos = data;
+       retval = kset->uevent_ops->uevent(kset, &dev->kobj,
+                                         envp, ARRAY_SIZE(envp),
+                                         pos, PAGE_SIZE);
+       if (retval)
+               goto out;
+
+       /* copy keys to file */
+       for (i = 0; envp[i]; i++) {
+               pos = &buf[count];
+               count += sprintf(pos, "%s\n", envp[i]);
+       }
+out:
+       return count;
+}
+
 static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
                            const char *buf, size_t count)
 {
@@ -621,10 +668,11 @@ int device_add(struct device *dev)
                                             BUS_NOTIFY_ADD_DEVICE, dev);
 
        dev->uevent_attr.attr.name = "uevent";
-       dev->uevent_attr.attr.mode = S_IWUSR;
+       dev->uevent_attr.attr.mode = S_IRUGO | S_IWUSR;
        if (dev->driver)
                dev->uevent_attr.attr.owner = dev->driver->owner;
        dev->uevent_attr.store = store_uevent;
+       dev->uevent_attr.show = show_uevent;
        error = device_create_file(dev, &dev->uevent_attr);
        if (error)
                goto attrError;