wmi: Add support for module autoloading

[net-next-2.6.git] / drivers / platform / x86 / wmi.c

diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
index 177f8d767df40f3a61528a1df582392121181969..e425a868cd3ad295063badaf90195fc57146b547 100644 (file)
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -30,6 +30,7 @@
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/device.h>
 #include <linux/list.h>
 #include <linux/acpi.h>
 #include <acpi/acpi_bus.h>
@@ -65,6 +66,7 @@ struct wmi_block {
        acpi_handle handle;
        wmi_notify_handler handler;
        void *handler_data;
+       struct device *dev;
 };
 
 static struct wmi_block wmi_blocks;
@@ -195,6 +197,34 @@ static bool wmi_parse_guid(const u8 *src, u8 *dest)
        return true;
 }
 
+/*
+ * Convert a raw GUID to the ACII string representation
+ */
+static int wmi_gtoa(const char *in, char *out)
+{
+       int i;
+
+       for (i = 3; i >= 0; i--)
+               out += sprintf(out, "%02X", in[i] & 0xFF);
+
+       out += sprintf(out, "-");
+       out += sprintf(out, "%02X", in[5] & 0xFF);
+       out += sprintf(out, "%02X", in[4] & 0xFF);
+       out += sprintf(out, "-");
+       out += sprintf(out, "%02X", in[7] & 0xFF);
+       out += sprintf(out, "%02X", in[6] & 0xFF);
+       out += sprintf(out, "-");
+       out += sprintf(out, "%02X", in[8] & 0xFF);
+       out += sprintf(out, "%02X", in[9] & 0xFF);
+       out += sprintf(out, "-");
+
+       for (i = 10; i <= 15; i++)
+               out += sprintf(out, "%02X", in[i] & 0xFF);
+
+       out = '\0';
+       return 0;
+}
+
 static bool find_guid(const char *guid_string, struct wmi_block **out)
 {
        char tmp[16], guid_input[16];
@@ -554,6 +584,138 @@ bool wmi_has_guid(const char *guid_string)
 }
 EXPORT_SYMBOL_GPL(wmi_has_guid);
 
+/*
+ * sysfs interface
+ */
+static ssize_t show_modalias(struct device *dev, struct device_attribute *attr,
+                            char *buf)
+{
+       char guid_string[37];
+       struct wmi_block *wblock;
+
+       wblock = dev_get_drvdata(dev);
+       if (!wblock)
+               return -ENOMEM;
+
+       wmi_gtoa(wblock->gblock.guid, guid_string);
+
+       return sprintf(buf, "wmi:%s\n", guid_string);
+}
+static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);
+
+static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+       char guid_string[37];
+
+       struct wmi_block *wblock;
+
+       if (add_uevent_var(env, "MODALIAS="))
+               return -ENOMEM;
+
+       wblock = dev_get_drvdata(dev);
+       if (!wblock)
+               return -ENOMEM;
+
+       wmi_gtoa(wblock->gblock.guid, guid_string);
+
+       strcpy(&env->buf[env->buflen - 1], "wmi:");
+       memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
+       env->buflen += 40;
+
+       return 0;
+}
+
+static void wmi_dev_free(struct device *dev)
+{
+       kfree(dev);
+}
+
+static struct class wmi_class = {
+       .name = "wmi",
+       .dev_release = wmi_dev_free,
+       .dev_uevent = wmi_dev_uevent,
+};
+
+static int wmi_create_devs(void)
+{
+       int result;
+       char guid_string[37];
+       struct guid_block *gblock;
+       struct wmi_block *wblock;
+       struct list_head *p;
+       struct device *guid_dev;
+
+       /* Create devices for all the GUIDs */
+       list_for_each(p, &wmi_blocks.list) {
+               wblock = list_entry(p, struct wmi_block, list);
+
+               guid_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
+               if (!guid_dev)
+                       return -ENOMEM;
+
+               wblock->dev = guid_dev;
+
+               guid_dev->class = &wmi_class;
+               dev_set_drvdata(guid_dev, wblock);
+
+               gblock = &wblock->gblock;
+
+               wmi_gtoa(gblock->guid, guid_string);
+               dev_set_name(guid_dev, guid_string);
+
+               result = device_register(guid_dev);
+               if (result)
+                       return result;
+
+               result = device_create_file(guid_dev, &dev_attr_modalias);
+               if (result)
+                       return result;
+       }
+
+       return 0;
+}
+
+static void wmi_remove_devs(void)
+{
+       struct guid_block *gblock;
+       struct wmi_block *wblock;
+       struct list_head *p;
+       struct device *guid_dev;
+
+       /* Delete devices for all the GUIDs */
+       list_for_each(p, &wmi_blocks.list) {
+               wblock = list_entry(p, struct wmi_block, list);
+
+               guid_dev = wblock->dev;
+               gblock = &wblock->gblock;
+
+               device_remove_file(guid_dev, &dev_attr_modalias);
+
+               device_unregister(guid_dev);
+       }
+}
+
+static void wmi_class_exit(void)
+{
+       wmi_remove_devs();
+       class_unregister(&wmi_class);
+}
+
+static int wmi_class_init(void)
+{
+       int ret;
+
+       ret = class_register(&wmi_class);
+       if (ret)
+               return ret;
+
+       ret = wmi_create_devs();
+       if (ret)
+               wmi_class_exit();
+
+       return ret;
+}
+
 /*
  * Parse the _WDG method for the GUID data blocks
  */
@@ -709,10 +871,17 @@ static int __init acpi_wmi_init(void)
 
        if (result < 0) {
                printk(KERN_INFO PREFIX "Error loading mapper\n");
-       } else {
-               printk(KERN_INFO PREFIX "Mapper loaded\n");
+               return -ENODEV;
+       }
+
+       result = wmi_class_init();
+       if (result) {
+               acpi_bus_unregister_driver(&acpi_wmi_driver);
+               return result;
        }
 
+       printk(KERN_INFO PREFIX "Mapper loaded\n");
+
        return result;
 }
 
@@ -721,6 +890,8 @@ static void __exit acpi_wmi_exit(void)
        struct list_head *p, *tmp;
        struct wmi_block *wblock;
 
+       wmi_class_exit();
+
        acpi_bus_unregister_driver(&acpi_wmi_driver);
 
        list_for_each_safe(p, tmp, &wmi_blocks.list) {