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>
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 0226e01..41c0602 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -922,7 +922,7 @@
}
/* 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 @@
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 @@
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 @@
/* 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 @@
* 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 @@
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 @@
/* 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 @@
/**
* 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 @@
*
* 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 @@
/* 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 @@
/* 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 @@
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 @@
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 @@
/**
* 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 @@
*
* 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 @@
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 @@
}
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 @@
*/
if (udev->skip_sys_resume)
return 0;
- return usb_external_resume_device(udev);
+ return usb_external_resume_device(udev, msg);
}
#endif /* CONFIG_PM */