USB: make autosuspend delay a module parameter
This patch (as859) makes the default USB autosuspend delay a module
parameter of usbcore. By setting the delay value at boot time, users
will be able to prevent the system from autosuspending devices which
for some reason can't handle it.
The patch also stores the autosuspend delay as a per-device value. A
later patch will allow the user to change the value, tailoring the
delay for each individual device. A delay value of 0 will prevent
autosuspend.
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 f9196a0..a420d72 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -963,12 +963,16 @@
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 @@
#define autosuspend_check(udev) 0
-#endif
+#endif /* CONFIG_USB_SUSPEND */
/**
* usb_suspend_both - suspend a USB device and its interfaces
@@ -1186,7 +1190,7 @@
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 @@
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;