USB: Fix core compile with CONFIG_USB_SUSPEND=n

When CONFIG_PM=n, make sure that the usb_[unlocked_][en/dis]able_lpm
declarations are visible in include/linux/usb.h, and exported from
drivers/usb/core/hub.c.

Before this patch, if CONFIG_USB_SUSPEND was turned off, it would cause
build errors:

drivers/usb/core/hub.c: In function 'usb_disable_lpm':
drivers/usb/core/hub.c:3394:2: error: implicit declaration of function 'usb_enable_lpm' [-Werror=implicit-function-declaration]
drivers/usb/core/hub.c: At top level:
drivers/usb/core/hub.c:3424:6: warning: conflicting types for 'usb_enable_lpm' [enabled by default]
drivers/usb/core/hub.c:3394:2: note: previous implicit declaration of 'usb_enable_lpm' was here
drivers/usb/core/driver.c: In function 'usb_probe_interface':
drivers/usb/core/driver.c:339:2: error: implicit declaration of function 'usb_unlocked_disable_lpm' [-Werror=implicit-function-declaration]
drivers/usb/core/driver.c:364:3: error: implicit declaration of function 'usb_unlocked_enable_lpm' [-Werror=implicit-function-declaration]
drivers/usb/core/message.c: In function 'usb_set_interface':
drivers/usb/core/message.c:1314:2: error: implicit declaration of function 'usb_disable_lpm' [-Werror=implicit-function-declaration]
drivers/usb/core/message.c:1323:3: error: implicit declaration of function 'usb_enable_lpm' [-Werror=implicit-function-declaration]
drivers/usb/core/message.c:1368:2: error: implicit declaration of function 'usb_unlocked_enable_lpm' [-Werror=implicit-function-declaration]

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Chen Peter-B29397 <B29397@freescale.com>

drivers/usb/core/hub.c

@@ -3472,15 +3472,19 @@ int usb_disable_lpm(struct usb_device *udev)
 {
 	return 0;
 }
+EXPORT_SYMBOL_GPL(usb_disable_lpm);
 
 void usb_enable_lpm(struct usb_device *udev) { }
+EXPORT_SYMBOL_GPL(usb_enable_lpm);
 
 int usb_unlocked_disable_lpm(struct usb_device *udev)
 {
 	return 0;
 }
+EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
 
 void usb_unlocked_enable_lpm(struct usb_device *udev) { }
+EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
 #endif
 
 

include/linux/usb.h

@@ -592,12 +592,6 @@ extern void usb_autopm_put_interface_async(struct usb_interface *intf);
 extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
 extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);
 
-extern int usb_disable_lpm(struct usb_device *udev);
-extern void usb_enable_lpm(struct usb_device *udev);
-/* Same as above, but these functions lock/unlock the bandwidth_mutex. */
-extern int usb_unlocked_disable_lpm(struct usb_device *udev);
-extern void usb_unlocked_enable_lpm(struct usb_device *udev);
-
 static inline void usb_mark_last_busy(struct usb_device *udev)
 {
 	pm_runtime_mark_last_busy(&udev->dev);
@@ -629,6 +623,12 @@ static inline void usb_mark_last_busy(struct usb_device *udev)
 { }
 #endif
 
+extern int usb_disable_lpm(struct usb_device *udev);
+extern void usb_enable_lpm(struct usb_device *udev);
+/* Same as above, but these functions lock/unlock the bandwidth_mutex. */
+extern int usb_unlocked_disable_lpm(struct usb_device *udev);
+extern void usb_unlocked_enable_lpm(struct usb_device *udev);
+
 /*-------------------------------------------------------------------------*/
 
 /* for drivers using iso endpoints */