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>
This commit is contained in:
Alan Stern
2007-02-20 15:00:53 -05:00
committed by Greg Kroah-Hartman
parent aa084f3efe
commit b5e795f8df
6 changed files with 36 additions and 10 deletions

View File

@ -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;
}