usbcore: split suspend/resume for device and interfaces

This patch (as716b) splits up the core suspend and resume routines into
two parts each: one for handling devices and one for handling
interfaces.  The behavior of the parts should be the same as in the old
unified code.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index a62de0a..b0db158 100644 (file)
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -751,81 +751,89 @@ EXPORT_SYMBOL_GPL_FUTURE(usb_deregister);
 
 #ifdef CONFIG_PM
 
-static int usb_suspend(struct device *dev, pm_message_t message)
+/* Caller has locked udev */
+static int suspend_device(struct usb_device *udev, pm_message_t msg)
 {
-       struct usb_device               *udev;
        struct usb_device_driver        *udriver;
-       struct usb_interface            *intf;
-       struct usb_driver               *driver;
-       int                             status;
 
-       if (is_usb_device(dev)) {
-               if (dev->driver == NULL)
-                       return 0;
-               udev = to_usb_device(dev);
-               udriver = to_usb_device_driver(dev->driver);
-               if (dev->power.power_state.event == message.event)
-                       return 0;
-               return udriver->suspend(udev, message);
-       }
+       if (udev->dev.driver == NULL)
+               return 0;
+       udriver = to_usb_device_driver(udev->dev.driver);
+       if (udev->dev.power.power_state.event == msg.event)
+               return 0;
+       return udriver->suspend(udev, msg);
+}
+
+/* Caller has locked udev */
+static int resume_device(struct usb_device *udev)
+{
+       struct usb_device_driver        *udriver;
 
-       if (dev->driver == NULL)
+       if (udev->dev.power.power_state.event == PM_EVENT_ON)
                return 0;
 
-       intf = to_usb_interface(dev);
-       driver = to_usb_driver(dev->driver);
+       /* mark things as "on" immediately, no matter what errors crop up */
+       udev->dev.power.power_state.event = PM_EVENT_ON;
+
+       if (udev->dev.driver == NULL)
+               return 0;
+       udriver = to_usb_device_driver(udev->dev.driver);
+       if (udev->state == USB_STATE_NOTATTACHED)
+               return 0;
+       return udriver->resume(udev);
+}
+
+/* Caller has locked intf */
+static int suspend_interface(struct usb_interface *intf, pm_message_t msg)
+{
+       struct usb_driver       *driver;
+       int                     status;
+
+       if (intf->dev.driver == NULL)
+               return 0;
+
+       driver = to_usb_driver(intf->dev.driver);
 
        /* with no hardware, USB interfaces only use FREEZE and ON states */
        if (!is_active(intf))
                return 0;
 
        if (driver->suspend && driver->resume) {
-               status = driver->suspend(intf, message);
+               status = driver->suspend(intf, msg);
                if (status)
-                       dev_err(dev, "%s error %d\n", "suspend", status);
+                       dev_err(&intf->dev, "%s error %d\n",
+                                       "suspend", status);
                else
                        mark_quiesced(intf);
        } else {
                // FIXME else if there's no suspend method, disconnect...
-               dev_warn(dev, "no suspend for driver %s?\n", driver->name);
+               dev_warn(&intf->dev, "no suspend for driver %s?\n",
+                               driver->name);
                mark_quiesced(intf);
                status = 0;
        }
        return status;
 }
 
-static int usb_resume(struct device *dev)
+/* Caller has locked intf */
+static int resume_interface(struct usb_interface *intf)
 {
-       struct usb_device               *udev;
-       struct usb_device_driver        *udriver;
-       struct usb_interface            *intf;
-       struct usb_driver               *driver;
-       int                             status;
+       struct usb_driver       *driver;
+       struct usb_device       *udev;
+       int                     status;
 
-       if (dev->power.power_state.event == PM_EVENT_ON)
+       if (intf->dev.power.power_state.event == PM_EVENT_ON)
                return 0;
 
        /* mark things as "on" immediately, no matter what errors crop up */
-       dev->power.power_state.event = PM_EVENT_ON;
+       intf->dev.power.power_state.event = PM_EVENT_ON;
 
-       /* devices resume through their hubs */
-       if (is_usb_device(dev)) {
-               if (dev->driver == NULL)
-                       return 0;
-               udev = to_usb_device(dev);
-               udriver = to_usb_device_driver(dev->driver);
-               if (udev->state == USB_STATE_NOTATTACHED)
-                       return 0;
-               return udriver->resume(udev);
-       }
-
-       if (dev->driver == NULL) {
-               dev->power.power_state.event = PM_EVENT_FREEZE;
+       if (intf->dev.driver == NULL) {
+               intf->dev.power.power_state.event = PM_EVENT_FREEZE;
                return 0;
        }
 
-       intf = to_usb_interface(dev);
-       driver = to_usb_driver(dev->driver);
+       driver = to_usb_driver(intf->dev.driver);
 
        udev = interface_to_usbdev(intf);
        if (udev->state == USB_STATE_NOTATTACHED)
@@ -838,14 +846,38 @@ static int usb_resume(struct device *dev)
        if (driver->resume) {
                status = driver->resume(intf);
                if (status) {
-                       dev_err(dev, "%s error %d\n", "resume", status);
+                       dev_err(&intf->dev, "%s error %d\n",
+                                       "resume", status);
                        mark_quiesced(intf);
                }
        } else
-               dev_warn(dev, "no resume for driver %s?\n", driver->name);
+               dev_warn(&intf->dev, "no resume for driver %s?\n",
+                               driver->name);
        return 0;
 }
 
+static int usb_suspend(struct device *dev, pm_message_t message)
+{
+       int     status;
+
+       if (is_usb_device(dev))
+               status = suspend_device(to_usb_device(dev), message);
+       else
+               status = suspend_interface(to_usb_interface(dev), message);
+       return status;
+}
+
+static int usb_resume(struct device *dev)
+{
+       int     status;
+
+       if (is_usb_device(dev))
+               status = resume_device(to_usb_device(dev));
+       else
+               status = resume_interface(to_usb_interface(dev));
+       return status;
+}
+
 #endif /* CONFIG_PM */
 
 struct bus_type usb_bus_type = {