tc1100-wmi - add error handling for device registration

Any of the platform API functions can fail; driver should be prepared
to handle such failures. Also:

 - changed to platform_driver_probe() since the device is created
   right there with the driver;
 - added __devexit annotation to remove method;
 - fixed memory leak on module unload - named platform_device_del() is not
   enough to free platform device, need platform_device_unregister().

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 30 insertions, 28 deletions

diff --git a/drivers/platform/x86/tc1100-wmi.c b/drivers/platform/x86/tc1100-wmi.c
index 0d53d5166574..fa2995bfa1d9 100644
--- a/drivers/platform/x86/tc1100-wmi.c
+++ b/drivers/platform/x86/tc1100-wmi.c
@@ -47,22 +47,6 @@ MODULE_DESCRIPTION("HP Compaq TC1100 Tablet WMI Extras");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("wmi:C364AC71-36DB-495A-8494-B439D472A505");
 
-static int tc1100_probe(struct platform_device *device);
-static int tc1100_remove(struct platform_device *device);
-static int tc1100_suspend(struct platform_device *device, pm_message_t state);
-static int tc1100_resume(struct platform_device *device);
-
-static struct platform_driver tc1100_driver = {
-        .driver = {
-                .name = "tc1100-wmi",
-                .owner = THIS_MODULE,
-        },
-        .probe = tc1100_probe,
-        .remove = tc1100_remove,
-        .suspend = tc1100_suspend,
-        .resume = tc1100_resume,
-};
-
 static struct platform_device *tc1100_device;
 
 struct tc1100_data {
@@ -197,13 +181,13 @@ static struct attribute_group tc1100_attribute_group = {
                                 Driver Model
    -------------------------------------------------------------------------- */
 
-static int tc1100_probe(struct platform_device *device)
+static int __init tc1100_probe(struct platform_device *device)
 {
         return sysfs_create_group(&device->dev.kobj, &tc1100_attribute_group);
 }
 
 
-static int tc1100_remove(struct platform_device *device)
+static int __devexit tc1100_remove(struct platform_device *device)
 {
         sysfs_remove_group(&device->dev.kobj, &tc1100_attribute_group);
 
@@ -240,31 +224,49 @@ static int tc1100_resume(struct platform_device *dev)
         return ret;
 }
 
+static struct platform_driver tc1100_driver = {
+        .driver = {
+                .name = "tc1100-wmi",
+                .owner = THIS_MODULE,
+        },
+        .remove = __devexit_p(tc1100_remove),
+        .suspend = tc1100_suspend,
+        .resume = tc1100_resume,
+};
+
 static int __init tc1100_init(void)
 {
-        int result = 0;
+        int error;
 
         if (!wmi_has_guid(GUID))
                 return -ENODEV;
 
-        result = platform_driver_register(&tc1100_driver);
-        if (result)
-                return result;
-
         tc1100_device = platform_device_alloc("tc1100-wmi", -1);
-        platform_device_add(tc1100_device);
+        if (!tc1100_device)
+                return -ENOMEM;
+
+        error = platform_device_add(tc1100_device);
+        if (error)
+                goto err_device_put;
+
+        error = platform_driver_probe(&tc1100_driver, tc1100_probe);
+        if (error)
+                goto err_device_del;
 
         printk(TC1100_INFO "HP Compaq TC1100 Tablet WMI Extras loaded\n");
+        return 0;
 
-        return result;
+ err_device_del:
+        platform_device_del(tc1100_device);
+ err_device_put:
+        platform_device_put(tc1100_device);
+        return error;
 }
 
 static void __exit tc1100_exit(void)
 {
-        platform_device_del(tc1100_device);
+        platform_device_unregister(tc1100_device);
         platform_driver_unregister(&tc1100_driver);
-
-        printk(TC1100_INFO "HP Compaq TC1100 Tablet WMI Extras unloaded\n");
 }
 
 module_init(tc1100_init);