USB: Enhance usage of pm_message_t

This patch (as1177) modifies the USB core suspend and resume
routines.  The resume functions now will take a pm_message_t argument,
so they will know what sort of resume is occurring.  The new argument
is also passed to the port suspend/resume and bus suspend/resume
routines (although they don't use it for anything but debugging).

In addition, special pm_message_t values are used for user-initiated,
device-initiated (i.e., remote wakeup), and automatic suspend/resume.
By testing these values, drivers can tell whether or not a particular
suspend was an autosuspend.  Unfortunately, they can't do the same for
resumes -- not until the pm_message_t argument is also passed to the
drivers' resume methods.  That will require a bigger change.

IMO, the whole Power Management framework should have been set up this
way in the first place.

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

8 files changed, 70 insertions, 60 deletions

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 0226e019326a..41c06025506e 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -922,7 +922,7 @@ static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
 }
 
 /* Caller has locked udev's pm_mutex */
-static int usb_resume_device(struct usb_device *udev)
+static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
 {
         struct usb_device_driver        *udriver;
         int                             status = 0;
@@ -940,7 +940,7 @@ static int usb_resume_device(struct usb_device *udev)
                 udev->reset_resume = 1;
 
         udriver = to_usb_device_driver(udev->dev.driver);
-        status = udriver->resume(udev);
+        status = udriver->resume(udev, msg);
 
  done:
         dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
@@ -969,7 +969,7 @@ static int usb_suspend_interface(struct usb_device *udev,
                 status = driver->suspend(intf, msg);
                 if (status == 0)
                         mark_quiesced(intf);
-                else if (!udev->auto_pm)
+                else if (!(msg.event & PM_EVENT_AUTO))
                         dev_err(&intf->dev, "%s error %d\n",
                                         "suspend", status);
         } else {
@@ -987,7 +987,7 @@ static int usb_suspend_interface(struct usb_device *udev,
 
 /* Caller has locked intf's usb_device's pm_mutex */
 static int usb_resume_interface(struct usb_device *udev,
-                struct usb_interface *intf, int reset_resume)
+                struct usb_interface *intf, pm_message_t msg, int reset_resume)
 {
         struct usb_driver       *driver;
         int                     status = 0;
@@ -1138,10 +1138,9 @@ static inline int autosuspend_check(struct usb_device *udev, int reschedule)
  * all the interfaces which were suspended are resumed so that they remain
  * in the same state as the device.
  *
- * If an autosuspend is in progress (@udev->auto_pm is set), the routine
- * checks first to make sure that neither the device itself or any of its
- * active interfaces is in use (pm_usage_cnt is greater than 0).  If they
- * are, the autosuspend fails.
+ * If an autosuspend is in progress the routine checks first to make sure
+ * that neither the device itself or any of its active interfaces is in use
+ * (pm_usage_cnt is greater than 0).  If they are, the autosuspend fails.
  *
  * If the suspend succeeds, the routine recursively queues an autosuspend
  * request for @udev's parent device, thereby propagating the change up
@@ -1176,7 +1175,7 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
 
         udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
 
-        if (udev->auto_pm) {
+        if (msg.event & PM_EVENT_AUTO) {
                 status = autosuspend_check(udev, 0);
                 if (status < 0)
                         goto done;
@@ -1196,13 +1195,16 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
 
         /* If the suspend failed, resume interfaces that did get suspended */
         if (status != 0) {
+                pm_message_t msg2;
+
+                msg2.event = msg.event ^ (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
                 while (--i >= 0) {
                         intf = udev->actconfig->interface[i];
-                        usb_resume_interface(udev, intf, 0);
+                        usb_resume_interface(udev, intf, msg2, 0);
                 }
 
                 /* Try another autosuspend when the interfaces aren't busy */
-                if (udev->auto_pm)
+                if (msg.event & PM_EVENT_AUTO)
                         autosuspend_check(udev, status == -EBUSY);
 
         /* If the suspend succeeded then prevent any more URB submissions,
@@ -1232,6 +1234,7 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
 /**
  * usb_resume_both - resume a USB device and its interfaces
  * @udev: the usb_device to resume
+ * @msg: Power Management message describing this state transition
  *
  * This is the central routine for resuming USB devices.  It calls the
  * the resume method for @udev and then calls the resume methods for all
@@ -1257,7 +1260,7 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
  *
  * This routine can run only in process context.
  */
-static int usb_resume_both(struct usb_device *udev)
+static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
 {
         int                     status = 0;
         int                     i;
@@ -1273,14 +1276,15 @@ static int usb_resume_both(struct usb_device *udev)
 
         /* Propagate the resume up the tree, if necessary */
         if (udev->state == USB_STATE_SUSPENDED) {
-                if (udev->auto_pm && udev->autoresume_disabled) {
+                if ((msg.event & PM_EVENT_AUTO) &&
+                                udev->autoresume_disabled) {
                         status = -EPERM;
                         goto done;
                 }
                 if (parent) {
                         status = usb_autoresume_device(parent);
                         if (status == 0) {
-                                status = usb_resume_device(udev);
+                                status = usb_resume_device(udev, msg);
                                 if (status || udev->state ==
                                                 USB_STATE_NOTATTACHED) {
                                         usb_autosuspend_device(parent);
@@ -1303,15 +1307,16 @@ static int usb_resume_both(struct usb_device *udev)
                         /* We can't progagate beyond the USB subsystem,
                          * so if a root hub's controller is suspended
                          * then we're stuck. */
-                        status = usb_resume_device(udev);
+                        status = usb_resume_device(udev, msg);
                 }
         } else if (udev->reset_resume)
-                status = usb_resume_device(udev);
+                status = usb_resume_device(udev, msg);
 
         if (status == 0 && udev->actconfig) {
                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
                         intf = udev->actconfig->interface[i];
-                        usb_resume_interface(udev, intf, udev->reset_resume);
+                        usb_resume_interface(udev, intf, msg,
+                                        udev->reset_resume);
                 }
         }
 
@@ -1339,13 +1344,13 @@ static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
                 udev->last_busy = jiffies;
         if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) {
                 if (udev->state == USB_STATE_SUSPENDED)
-                        status = usb_resume_both(udev);
+                        status = usb_resume_both(udev, PMSG_AUTO_RESUME);
                 if (status != 0)
                         udev->pm_usage_cnt -= inc_usage_cnt;
                 else if (inc_usage_cnt)
                         udev->last_busy = jiffies;
         } else if (inc_usage_cnt <= 0 && udev->pm_usage_cnt <= 0) {
-                status = usb_suspend_both(udev, PMSG_SUSPEND);
+                status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
         }
         usb_pm_unlock(udev);
         return status;
@@ -1469,13 +1474,14 @@ static int usb_autopm_do_interface(struct usb_interface *intf,
                 udev->last_busy = jiffies;
                 if (inc_usage_cnt >= 0 && intf->pm_usage_cnt > 0) {
                         if (udev->state == USB_STATE_SUSPENDED)
-                                status = usb_resume_both(udev);
+                                status = usb_resume_both(udev,
+                                                PMSG_AUTO_RESUME);
                         if (status != 0)
                                 intf->pm_usage_cnt -= inc_usage_cnt;
                         else
                                 udev->last_busy = jiffies;
                 } else if (inc_usage_cnt <= 0 && intf->pm_usage_cnt <= 0) {
-                        status = usb_suspend_both(udev, PMSG_SUSPEND);
+                        status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
                 }
         }
         usb_pm_unlock(udev);
@@ -1700,6 +1706,7 @@ int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
 /**
  * usb_external_resume_device - external resume of a USB device and its interfaces
  * @udev: the usb_device to resume
+ * @msg: Power Management message describing this state transition
  *
  * This routine handles external resume requests: ones not generated
  * internally by a USB driver (autoresume) but rather coming from the user
@@ -1708,13 +1715,13 @@ int usb_external_suspend_device(struct usb_device *udev, pm_message_t msg)
  *
  * The caller must hold @udev's device lock.
  */
-int usb_external_resume_device(struct usb_device *udev)
+int usb_external_resume_device(struct usb_device *udev, pm_message_t msg)
 {
         int     status;
 
         usb_pm_lock(udev);
         udev->auto_pm = 0;
-        status = usb_resume_both(udev);
+        status = usb_resume_both(udev, msg);
         udev->last_busy = jiffies;
         usb_pm_unlock(udev);
         if (status == 0)
@@ -1727,7 +1734,7 @@ int usb_external_resume_device(struct usb_device *udev)
         return status;
 }
 
-int usb_suspend(struct device *dev, pm_message_t message)
+int usb_suspend(struct device *dev, pm_message_t msg)
 {
         struct usb_device       *udev;
 
@@ -1746,10 +1753,10 @@ int usb_suspend(struct device *dev, pm_message_t message)
         }
 
         udev->skip_sys_resume = 0;
-        return usb_external_suspend_device(udev, message);
+        return usb_external_suspend_device(udev, msg);
 }
 
-int usb_resume(struct device *dev)
+int usb_resume(struct device *dev, pm_message_t msg)
 {
         struct usb_device       *udev;
 
@@ -1761,7 +1768,7 @@ int usb_resume(struct device *dev)
          */
         if (udev->skip_sys_resume)
                 return 0;
-        return usb_external_resume_device(udev);
+        return usb_external_resume_device(udev, msg);
 }
 
 #endif /* CONFIG_PM */
diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c
index 7e912f21fd36..30ecac3af15a 100644
--- a/drivers/usb/core/generic.c
+++ b/drivers/usb/core/generic.c
@@ -200,18 +200,18 @@ static int generic_suspend(struct usb_device *udev, pm_message_t msg)
          * interfaces manually by doing a bus (or "global") suspend.
          */
         if (!udev->parent)
-                rc = hcd_bus_suspend(udev);
+                rc = hcd_bus_suspend(udev, msg);
 
         /* Non-root devices don't need to do anything for FREEZE or PRETHAW */
         else if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_PRETHAW)
                 rc = 0;
         else
-                rc = usb_port_suspend(udev);
+                rc = usb_port_suspend(udev, msg);
 
         return rc;
 }
 
-static int generic_resume(struct usb_device *udev)
+static int generic_resume(struct usb_device *udev, pm_message_t msg)
 {
         int rc;
 
@@ -221,9 +221,9 @@ static int generic_resume(struct usb_device *udev)
          * interfaces manually by doing a bus (or "global") resume.
          */
         if (!udev->parent)
-                rc = hcd_bus_resume(udev);
+                rc = hcd_bus_resume(udev, msg);
         else
-                rc = usb_port_resume(udev);
+                rc = usb_port_resume(udev, msg);
         return rc;
 }
 
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 7403ed871abd..a0079876d74e 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1573,14 +1573,14 @@ int usb_hcd_get_frame_number (struct usb_device *udev)
 
 #ifdef  CONFIG_PM
 
-int hcd_bus_suspend(struct usb_device *rhdev)
+int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
 {
         struct usb_hcd  *hcd = container_of(rhdev->bus, struct usb_hcd, self);
         int             status;
         int             old_state = hcd->state;
 
         dev_dbg(&rhdev->dev, "bus %s%s\n",
-                        rhdev->auto_pm ? "auto-" : "", "suspend");
+                        (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "suspend");
         if (!hcd->driver->bus_suspend) {
                 status = -ENOENT;
         } else {
@@ -1598,14 +1598,14 @@ int hcd_bus_suspend(struct usb_device *rhdev)
         return status;
 }
 
-int hcd_bus_resume(struct usb_device *rhdev)
+int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
 {
         struct usb_hcd  *hcd = container_of(rhdev->bus, struct usb_hcd, self);
         int             status;
         int             old_state = hcd->state;
 
         dev_dbg(&rhdev->dev, "usb %s%s\n",
-                        rhdev->auto_pm ? "auto-" : "", "resume");
+                        (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "resume");
         if (!hcd->driver->bus_resume)
                 return -ENOENT;
         if (hcd->state == HC_STATE_RUNNING)
@@ -1638,7 +1638,7 @@ static void hcd_resume_work(struct work_struct *work)
 
         usb_lock_device(udev);
         usb_mark_last_busy(udev);
-        usb_external_resume_device(udev);
+        usb_external_resume_device(udev, PMSG_REMOTE_RESUME);
         usb_unlock_device(udev);
 }
 
diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h
index 0aaa9cea6b38..aa5da82d9071 100644
--- a/drivers/usb/core/hcd.h
+++ b/drivers/usb/core/hcd.h
@@ -388,8 +388,8 @@ extern int usb_find_interface_driver(struct usb_device *dev,
 #ifdef CONFIG_PM
 extern void usb_hcd_resume_root_hub(struct usb_hcd *hcd);
 extern void usb_root_hub_lost_power(struct usb_device *rhdev);
-extern int hcd_bus_suspend(struct usb_device *rhdev);
-extern int hcd_bus_resume(struct usb_device *rhdev);
+extern int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg);
+extern int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg);
 #else
 static inline void usb_hcd_resume_root_hub(struct usb_hcd *hcd)
 {
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index ff066edf4dca..fc99ef67761d 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1984,7 +1984,7 @@ static int check_port_resume_type(struct usb_device *udev,
  *
  * Returns 0 on success, else negative errno.
  */
-int usb_port_suspend(struct usb_device *udev)
+int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
 {
         struct usb_hub  *hub = hdev_to_hub(udev->parent);
         int             port1 = udev->portnum;
@@ -2023,7 +2023,7 @@ int usb_port_suspend(struct usb_device *udev)
         } else {
                 /* device has up to 10 msec to fully suspend */
                 dev_dbg(&udev->dev, "usb %ssuspend\n",
-                                udev->auto_pm ? "auto-" : "");
+                                (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
                 msleep(10);
         }
@@ -2142,7 +2142,7 @@ static int finish_port_resume(struct usb_device *udev)
  *
  * Returns 0 on success, else negative errno.
  */
-int usb_port_resume(struct usb_device *udev)
+int usb_port_resume(struct usb_device *udev, pm_message_t msg)
 {
         struct usb_hub  *hub = hdev_to_hub(udev->parent);
         int             port1 = udev->portnum;
@@ -2167,7 +2167,7 @@ int usb_port_resume(struct usb_device *udev)
         } else {
                 /* drive resume for at least 20 msec */
                 dev_dbg(&udev->dev, "usb %sresume\n",
-                                udev->auto_pm ? "auto-" : "");
+                                (msg.event & PM_EVENT_AUTO ? "auto-" : ""));
                 msleep(25);
 
                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
@@ -2208,7 +2208,7 @@ static int remote_wakeup(struct usb_device *udev)
         if (udev->state == USB_STATE_SUSPENDED) {
                 dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
                 usb_mark_last_busy(udev);
-                status = usb_external_resume_device(udev);
+                status = usb_external_resume_device(udev, PMSG_REMOTE_RESUME);
         }
         return status;
 }
@@ -2217,14 +2217,14 @@ static int remote_wakeup(struct usb_device *udev)
 
 /* When CONFIG_USB_SUSPEND isn't set, we never suspend or resume any ports. */
 
-int usb_port_suspend(struct usb_device *udev)
+int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
 {
         return 0;
 }
 
 /* However we may need to do a reset-resume */
 
-int usb_port_resume(struct usb_device *udev)
+int usb_port_resume(struct usb_device *udev, pm_message_t msg)
 {
         struct usb_hub  *hub = hdev_to_hub(udev->parent);
         int             port1 = udev->portnum;
@@ -2264,7 +2264,7 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
 
                 udev = hdev->children [port1-1];
                 if (udev && udev->can_submit) {
-                        if (!hdev->auto_pm)
+                        if (!(msg.event & PM_EVENT_AUTO))
                                 dev_dbg(&intf->dev, "port %d nyet suspended\n",
                                                 port1);
                         return -EBUSY;
diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c
index 8c65fa75b5c2..0f0ccf640114 100644
--- a/drivers/usb/core/sysfs.c
+++ b/drivers/usb/core/sysfs.c
@@ -359,19 +359,19 @@ set_level(struct device *dev, struct device_attribute *attr,
                         strncmp(buf, on_string, len) == 0) {
                 udev->autosuspend_disabled = 1;
                 udev->autoresume_disabled = 0;
-                rc = usb_external_resume_device(udev);
+                rc = usb_external_resume_device(udev, PMSG_USER_RESUME);
 
         } else if (len == sizeof auto_string - 1 &&
                         strncmp(buf, auto_string, len) == 0) {
                 udev->autosuspend_disabled = 0;
                 udev->autoresume_disabled = 0;
-                rc = usb_external_resume_device(udev);
+                rc = usb_external_resume_device(udev, PMSG_USER_RESUME);
 
         } else if (len == sizeof suspend_string - 1 &&
                         strncmp(buf, suspend_string, len) == 0) {
                 udev->autosuspend_disabled = 0;
                 udev->autoresume_disabled = 1;
-                rc = usb_external_suspend_device(udev, PMSG_SUSPEND);
+                rc = usb_external_suspend_device(udev, PMSG_USER_SUSPEND);
 
         } else
                 rc = -EINVAL;
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 51854c2bc912..4c98f3975afe 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -253,7 +253,7 @@ static int usb_dev_prepare(struct device *dev)
 static void usb_dev_complete(struct device *dev)
 {
         /* Currently used only for rebinding interfaces */
-        usb_resume(dev);        /* Implement eventually? */
+        usb_resume(dev, PMSG_RESUME);   /* Message event is meaningless */
 }
 
 static int usb_dev_suspend(struct device *dev)
@@ -263,7 +263,7 @@ static int usb_dev_suspend(struct device *dev)
 
 static int usb_dev_resume(struct device *dev)
 {
-        return usb_resume(dev);
+        return usb_resume(dev, PMSG_RESUME);
 }
 
 static int usb_dev_freeze(struct device *dev)
@@ -273,7 +273,7 @@ static int usb_dev_freeze(struct device *dev)
 
 static int usb_dev_thaw(struct device *dev)
 {
-        return usb_resume(dev);
+        return usb_resume(dev, PMSG_THAW);
 }
 
 static int usb_dev_poweroff(struct device *dev)
@@ -283,7 +283,7 @@ static int usb_dev_poweroff(struct device *dev)
 
 static int usb_dev_restore(struct device *dev)
 {
-        return usb_resume(dev);
+        return usb_resume(dev, PMSG_RESTORE);
 }
 
 static struct dev_pm_ops usb_device_pm_ops = {
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index b60ebb4de1a8..9fb195665fa8 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -1,3 +1,5 @@
+#include <linux/pm.h>
+
 /* Functions local to drivers/usb/core/ */
 
 extern int usb_create_sysfs_dev_files(struct usb_device *dev);
@@ -42,15 +44,16 @@ extern void usb_host_cleanup(void);
 #ifdef  CONFIG_PM
 
 extern int usb_suspend(struct device *dev, pm_message_t msg);
-extern int usb_resume(struct device *dev);
+extern int usb_resume(struct device *dev, pm_message_t msg);
 
 extern void usb_autosuspend_work(struct work_struct *work);
 extern void usb_autoresume_work(struct work_struct *work);
-extern int usb_port_suspend(struct usb_device *dev);
-extern int usb_port_resume(struct usb_device *dev);
+extern int usb_port_suspend(struct usb_device *dev, pm_message_t msg);
+extern int usb_port_resume(struct usb_device *dev, pm_message_t msg);
 extern int usb_external_suspend_device(struct usb_device *udev,
                 pm_message_t msg);
-extern int usb_external_resume_device(struct usb_device *udev);
+extern int usb_external_resume_device(struct usb_device *udev,
+                pm_message_t msg);
 
 static inline void usb_pm_lock(struct usb_device *udev)
 {
@@ -64,12 +67,12 @@ static inline void usb_pm_unlock(struct usb_device *udev)
 
 #else
 
-static inline int usb_port_suspend(struct usb_device *udev)
+static inline int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
 {
         return 0;
 }
 
-static inline int usb_port_resume(struct usb_device *udev)
+static inline int usb_port_resume(struct usb_device *udev, pm_message_t msg)
 {
         return 0;
 }