USB: flush outstanding URBs when suspending

This patch (as989) makes usbcore flush all outstanding URBs for each
device as the device is suspended.  This will be true even when
CONFIG_USB_SUSPEND is not enabled.

In addition, an extra can_submit flag is added to the usb_device
structure.  That flag will be turned off whenever a suspend request
has been received for the device, even if the device isn't actually
suspended because CONFIG_USB_SUSPEND isn't set.

It's no longer necessary to check for the device state being equal to
USB_STATE_SUSPENDED during URB submission; that check can be replaced
by a check of the can_submit flag.  This also permits us to remove
some questionable references to the deprecated power.power_state field.

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 ca43a6f..ba5bbc7 100644 (file)
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1102,9 +1102,16 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
                if (udev->auto_pm)
                        autosuspend_check(udev);
 
-       /* If the suspend succeeded, propagate it up the tree */
+       /* If the suspend succeeded then prevent any more URB submissions,
+        * flush any outstanding URBs, and propagate the suspend up the tree.
+        */
        } else {
                cancel_delayed_work(&udev->autosuspend);
+               udev->can_submit = 0;
+               for (i = 0; i < 16; ++i) {
+                       usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
+                       usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
+               }
                if (parent)
                        usb_autosuspend_device(parent);
        }
@@ -1154,6 +1161,7 @@ static int usb_resume_both(struct usb_device *udev)
                status = -ENODEV;
                goto done;
        }
+       udev->can_submit = 1;
 
        /* Propagate the resume up the tree, if necessary */
        if (udev->state == USB_STATE_SUSPENDED) {

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index e5874e8..2c79aa6 100644 (file)
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1014,6 +1014,11 @@ int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
                goto done;
        }
 
+       if (unlikely(!urb->dev->can_submit)) {
+               rc = -EHOSTUNREACH;
+               goto done;
+       }
+
        /*
         * Check the host controller's state and add the URB to the
         * endpoint's queue.

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index bd08d51..691acf2 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1955,14 +1955,7 @@ static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
                struct usb_device       *udev;
 
                udev = hdev->children [port1-1];
-               if (udev && msg.event == PM_EVENT_SUSPEND &&
-#ifdef CONFIG_USB_SUSPEND
-                               udev->state != USB_STATE_SUSPENDED
-#else
-                               udev->dev.power.power_state.event
-                                       == PM_EVENT_ON
-#endif
-                               ) {
+               if (udev && udev->can_submit) {
                        if (!hdev->auto_pm)
                                dev_dbg(&intf->dev, "port %d nyet suspended\n",
                                                port1);

diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index 76db76f..c20c03a 100644 (file)
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -286,9 +286,6 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
                return -EINVAL;
        if (!(dev = urb->dev) || dev->state < USB_STATE_DEFAULT)
                return -ENODEV;
-       if (dev->bus->controller->power.power_state.event != PM_EVENT_ON
-                       || dev->state == USB_STATE_SUSPENDED)
-               return -EHOSTUNREACH;
 
        /* For now, get the endpoint from the pipe.  Eventually drivers
         * will be required to set urb->ep directly and we will eliminate

diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index e5ff161..8121edb 100644 (file)
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -272,6 +272,7 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
        dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
        /* ep0 maxpacket comes later, from device descriptor */
        usb_enable_endpoint(dev, &dev->ep0);
+       dev->can_submit = 1;
 
        /* Save readable and stable topology id, distinguishing devices
         * by location for diagnostics, tools, driver model, etc.  The

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 5b14b4c..e5b35e0 100644 (file)
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -383,6 +383,7 @@ struct usb_device {
        u8 portnum;                     /* Parent port number (origin 1) */
        u8 level;                       /* Number of USB hub ancestors */
 
+       unsigned can_submit:1;          /* URBs may be submitted */
        unsigned discon_suspended:1;    /* Disconnected while suspended */
        unsigned have_langid:1;         /* whether string_langid is valid */
        unsigned authorized:1;          /* Policy has determined we can use it */