6 files changed, 36 insertions, 10 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index c479d30eeaa3..03eb5ed503f7 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1758,6 +1758,13 @@ and is between 256 and 4096 characters. It is defined in the file
                         Note that genuine overcurrent events won't be
                         reported either.
 
+        usbcore.autosuspend=
+                        [USB] The autosuspend time delay (in seconds) used
+                        for newly-detected USB devices (default 2).  This
+                        is the time required before an idle device will be
+                        autosuspended.  Devices for which the delay is set
+                        to 0 won't be autosuspended at all.
+
         usbhid.mousepoll=
                         [USBHID] The interval which mice are to be polled at.
 
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index f9196a0a9412..a420d72a0254 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -963,12 +963,16 @@ static int autosuspend_check(struct usb_device *udev)
         int                     i;
         struct usb_interface    *intf;
 
-        /* For autosuspend, fail fast if anything is in use.
-         * Also fail if any interfaces require remote wakeup but it
-         * isn't available. */
+        /* For autosuspend, fail fast if anything is in use or autosuspend
+         * is disabled.  Also fail if any interfaces require remote wakeup
+         * but it isn't available.
+         */
         udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
         if (udev->pm_usage_cnt > 0)
                 return -EBUSY;
+        if (!udev->autosuspend_delay)
+                return -EPERM;
+
         if (udev->actconfig) {
                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
                         intf = udev->actconfig->interface[i];
@@ -991,7 +995,7 @@ static int autosuspend_check(struct usb_device *udev)
 
 #define autosuspend_check(udev)         0
 
-#endif
+#endif  /* CONFIG_USB_SUSPEND */
 
 /**
  * usb_suspend_both - suspend a USB device and its interfaces
@@ -1186,7 +1190,7 @@ static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt)
                         udev->pm_usage_cnt -= inc_usage_cnt;
         } else if (inc_usage_cnt <= 0 && autosuspend_check(udev) == 0)
                 queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
-                                USB_AUTOSUSPEND_DELAY);
+                                udev->autosuspend_delay);
         usb_pm_unlock(udev);
         return status;
 }
@@ -1270,7 +1274,7 @@ static int usb_autopm_do_interface(struct usb_interface *intf,
                                 intf->pm_usage_cnt -= inc_usage_cnt;
                 } else if (inc_usage_cnt <= 0 && autosuspend_check(udev) == 0)
                         queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend,
-                                        USB_AUTOSUSPEND_DELAY);
+                                        udev->autosuspend_delay);
         }
         usb_pm_unlock(udev);
         return status;
diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
index ea0e48e9f611..0e5c646cb4f6 100644
--- a/drivers/usb/core/quirks.c
+++ b/drivers/usb/core/quirks.c
@@ -39,8 +39,10 @@ static const struct usb_device_id usb_quirk_list[] = {
 
 static void usb_autosuspend_quirk(struct usb_device *udev)
 {
-        /* unbalanced resume to prevent autosuspends */
-        usb_autoresume_device(udev);
+#ifdef  CONFIG_USB_SUSPEND
+        /* disable autosuspend, but allow the user to re-enable it via sysfs */
+        udev->autosuspend_delay = 0;
+#endif
 }
 
 static const struct usb_device_id *find_id(struct usb_device *udev)
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 3db721cd557a..54b42ce311c1 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -22,6 +22,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/string.h>
 #include <linux/bitops.h>
 #include <linux/slab.h>
@@ -50,6 +51,16 @@ static int nousb;	/* Disable USB when built into kernel image */
 
 struct workqueue_struct *ksuspend_usb_wq;       /* For autosuspend */
 
+#ifdef  CONFIG_USB_SUSPEND
+static int usb_autosuspend_delay = 2;           /* Default delay value,
+                                                 * in seconds */
+module_param_named(autosuspend, usb_autosuspend_delay, uint, 0644);
+MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
+
+#else
+#define usb_autosuspend_delay           0
+#endif
+
 
 /**
  * usb_ifnum_to_if - get the interface object with a given interface number
@@ -306,6 +317,7 @@ usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
 #ifdef  CONFIG_PM
         mutex_init(&dev->pm_mutex);
         INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work);
+        dev->autosuspend_delay = usb_autosuspend_delay * HZ;
 #endif
         return dev;
 }
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index 045cbd111887..b0a35f45b099 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -65,8 +65,6 @@ static inline void usb_pm_unlock(struct usb_device *udev) {}
 
 #ifdef CONFIG_USB_SUSPEND
 
-#define USB_AUTOSUSPEND_DELAY   (HZ*2)
-
 extern void usb_autosuspend_device(struct usb_device *udev);
 extern int usb_autoresume_device(struct usb_device *udev);
 
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 37e522eba47f..87dc75a6cee1 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -389,10 +389,13 @@ struct usb_device {
 
         int pm_usage_cnt;               /* usage counter for autosuspend */
         u32 quirks;                     /* quirks of the whole device */
+
 #ifdef CONFIG_PM
         struct delayed_work autosuspend; /* for delayed autosuspends */
         struct mutex pm_mutex;          /* protects PM operations */
 
+        unsigned autosuspend_delay;     /* in jiffies */
+
         unsigned auto_pm:1;             /* autosuspend/resume in progress */
         unsigned do_remote_wakeup:1;    /* remote wakeup should be enabled */
 #endif