Driver core: Make platform_device.id an int

While platform_device.id is a u32, platform_device_add() handles "-1"
as a special id value. This has potential for confusion and bugs.
Making it an int instead should prevent problems from happening in
the future.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 8bbd459..e808043 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -15,7 +15,7 @@
 
 struct platform_device {
 	const char	* name;
-	u32		id;
+	int		id;
 	struct device	dev;
 	u32		num_resources;
 	struct resource	* resource;
@@ -35,9 +35,10 @@
 extern int platform_get_irq_byname(struct platform_device *, char *);
 extern int platform_add_devices(struct platform_device **, int);
 
-extern struct platform_device *platform_device_register_simple(char *, unsigned int, struct resource *, unsigned int);
+extern struct platform_device *platform_device_register_simple(char *, int id,
+					struct resource *, unsigned int);
 
-extern struct platform_device *platform_device_alloc(const char *name, unsigned int id);
+extern struct platform_device *platform_device_alloc(const char *name, int id);
 extern int platform_device_add_resources(struct platform_device *pdev, struct resource *res, unsigned int num);
 extern int platform_device_add_data(struct platform_device *pdev, const void *data, size_t size);
 extern int platform_device_add(struct platform_device *pdev);