From stern@rowland.harvard.edu Mon Nov 20 08:39:01 2006 Date: Mon, 20 Nov 2006 11:38:46 -0500 (EST) From: Alan Stern To: Greg KH cc: USB development list Subject: usbcore: remove unused argument in autosuspend Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Thanks to several earlier patches, usb_autosuspend_device() and usb_autoresume_device() are never called with a second argument other than 1. This patch (as819) removes the now-redundant argument. It also consolidates some common code between those two routines, putting it into a new subroutine called usb_autopm_do_device(). And it includes a sizable kerneldoc update for the affected functions. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/devio.c | 4 - drivers/usb/core/driver.c | 104 ++++++++++++++++++++++++--------------------- drivers/usb/core/hub.c | 12 ++--- drivers/usb/core/message.c | 6 +- drivers/usb/core/usb.h | 9 +-- 5 files changed, 72 insertions(+), 63 deletions(-) --- gregkh-2.6.orig/drivers/usb/core/devio.c +++ gregkh-2.6/drivers/usb/core/devio.c @@ -561,7 +561,7 @@ static int usbdev_open(struct inode *ino dev = inode->i_private; if (!dev) goto out; - ret = usb_autoresume_device(dev, 1); + ret = usb_autoresume_device(dev); if (ret) goto out; @@ -609,7 +609,7 @@ static int usbdev_release(struct inode * releaseintf(ps, ifnum); } destroy_all_async(ps); - usb_autosuspend_device(dev, 1); + usb_autosuspend_device(dev); usb_unlock_device(dev); usb_put_dev(dev); put_pid(ps->disc_pid); --- gregkh-2.6.orig/drivers/usb/core/driver.c +++ gregkh-2.6/drivers/usb/core/driver.c @@ -205,7 +205,7 @@ static int usb_probe_interface(struct de if (id) { dev_dbg(dev, "%s - got id\n", __FUNCTION__); - error = usb_autoresume_device(udev, 1); + error = usb_autoresume_device(udev); if (error) return error; @@ -229,7 +229,7 @@ static int usb_probe_interface(struct de } else intf->condition = USB_INTERFACE_BOUND; - usb_autosuspend_device(udev, 1); + usb_autosuspend_device(udev); } return error; @@ -247,7 +247,7 @@ static int usb_unbind_interface(struct d /* Autoresume for set_interface call below */ udev = interface_to_usbdev(intf); - error = usb_autoresume_device(udev, 1); + error = usb_autoresume_device(udev); /* release all urbs for this interface */ usb_disable_interface(interface_to_usbdev(intf), intf); @@ -265,7 +265,7 @@ static int usb_unbind_interface(struct d intf->needs_remote_wakeup = 0; if (!error) - usb_autosuspend_device(udev, 1); + usb_autosuspend_device(udev); return 0; } @@ -940,6 +940,8 @@ done: return status; } +#ifdef CONFIG_USB_SUSPEND + /* Internal routine to check whether we may autosuspend a device. */ static int autosuspend_check(struct usb_device *udev) { @@ -970,6 +972,12 @@ static int autosuspend_check(struct usb_ return 0; } +#else + +#define autosuspend_check(udev) 0 + +#endif + /** * usb_suspend_both - suspend a USB device and its interfaces * @udev: the usb_device to suspend @@ -1048,7 +1056,7 @@ int usb_suspend_both(struct usb_device * /* If the suspend succeeded, propagate it up the tree */ } else if (parent) - usb_autosuspend_device(parent, 1); + usb_autosuspend_device(parent); // dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status); return status; @@ -1096,11 +1104,11 @@ int usb_resume_both(struct usb_device *u /* Propagate the resume up the tree, if necessary */ if (udev->state == USB_STATE_SUSPENDED) { if (parent) { - status = usb_autoresume_device(parent, 1); + status = usb_autoresume_device(parent); if (status == 0) { status = usb_resume_device(udev); if (status) { - usb_autosuspend_device(parent, 1); + usb_autosuspend_device(parent); /* It's possible usb_resume_device() * failed after the port was @@ -1146,39 +1154,53 @@ int usb_resume_both(struct usb_device *u #ifdef CONFIG_USB_SUSPEND +/* Internal routine to adjust a device's usage counter and change + * its autosuspend state. + */ +static int usb_autopm_do_device(struct usb_device *udev, int inc_usage_cnt) +{ + int status = 0; + + usb_pm_lock(udev); + udev->pm_usage_cnt += inc_usage_cnt; + WARN_ON(udev->pm_usage_cnt < 0); + if (inc_usage_cnt >= 0 && udev->pm_usage_cnt > 0) { + udev->auto_pm = 1; + status = usb_resume_both(udev); + if (status != 0) + 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); + usb_pm_unlock(udev); + return status; +} + /** * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces * @udev: the usb_device to autosuspend - * @dec_usage_cnt: flag to decrement @udev's PM-usage counter * * This routine should be called when a core subsystem is finished using * @udev and wants to allow it to autosuspend. Examples would be when * @udev's device file in usbfs is closed or after a configuration change. * - * @dec_usage_cnt should be 1 if the subsystem previously incremented - * @udev's usage counter (such as by passing 1 to usb_autoresume_device); - * otherwise it should be 0. - * - * If the usage counter for @udev or any of its active interfaces is greater - * than 0, the autosuspend request will not be queued. (If an interface - * driver does not support autosuspend then its usage counter is permanently - * positive.) Likewise, if an interface driver requires remote-wakeup - * capability during autosuspend but remote wakeup is disabled, the - * autosuspend will fail. + * @udev's usage counter is decremented. If it or any of the usage counters + * for an active interface is greater than 0, no autosuspend request will be + * queued. (If an interface driver does not support autosuspend then its + * usage counter is permanently positive.) Furthermore, if an interface + * driver requires remote-wakeup capability during autosuspend but remote + * wakeup is disabled, the autosuspend will fail. * * Often the caller will hold @udev's device lock, but this is not * necessary. * * This routine can run only in process context. */ -void usb_autosuspend_device(struct usb_device *udev, int dec_usage_cnt) +void usb_autosuspend_device(struct usb_device *udev) { - usb_pm_lock(udev); - udev->pm_usage_cnt -= dec_usage_cnt; - if (autosuspend_check(udev) == 0) - queue_delayed_work(ksuspend_usb_wq, &udev->autosuspend, - USB_AUTOSUSPEND_DELAY); - usb_pm_unlock(udev); + int status; + + status = usb_autopm_do_device(udev, -1); // dev_dbg(&udev->dev, "%s: cnt %d\n", // __FUNCTION__, udev->pm_usage_cnt); } @@ -1186,39 +1208,27 @@ void usb_autosuspend_device(struct usb_d /** * usb_autoresume_device - immediately autoresume a USB device and its interfaces * @udev: the usb_device to autoresume - * @inc_usage_cnt: flag to increment @udev's PM-usage counter * * This routine should be called when a core subsystem wants to use @udev - * and needs to guarantee that it is not suspended. In addition, the - * caller can prevent @udev from being autosuspended subsequently. (Note - * that this will not prevent suspend events originating in the PM core.) - * Examples would be when @udev's device file in usbfs is opened (autosuspend - * should be prevented until the file is closed) or when a remote-wakeup - * request is received (later autosuspends should not be prevented). - * - * @inc_usage_cnt should be 1 to increment @udev's usage counter and prevent - * autosuspends. This prevention will persist until the usage counter is - * decremented again (such as by passing 1 to usb_autosuspend_device). - * Otherwise @inc_usage_cnt should be 0 to leave the usage counter unchanged. - * Regardless, if the autoresume fails then the usage counter is not - * incremented. + * and needs to guarantee that it is not suspended. No autosuspend will + * occur until usb_autosuspend_device is called. (Note that this will not + * prevent suspend events originating in the PM core.) Examples would be + * when @udev's device file in usbfs is opened or when a remote-wakeup + * request is received. + * + * @udev's usage counter is incremented to prevent subsequent autosuspends. + * However if the autoresume fails then the usage counter is re-decremented. * * Often the caller will hold @udev's device lock, but this is not * necessary (and attempting it might cause deadlock). * * This routine can run only in process context. */ -int usb_autoresume_device(struct usb_device *udev, int inc_usage_cnt) +int usb_autoresume_device(struct usb_device *udev) { int status; - usb_pm_lock(udev); - udev->pm_usage_cnt += inc_usage_cnt; - udev->auto_pm = 1; - status = usb_resume_both(udev); - if (status != 0) - udev->pm_usage_cnt -= inc_usage_cnt; - usb_pm_unlock(udev); + status = usb_autopm_do_device(udev, 1); // dev_dbg(&udev->dev, "%s: status %d cnt %d\n", // __FUNCTION__, status, udev->pm_usage_cnt); return status; --- gregkh-2.6.orig/drivers/usb/core/hub.c +++ gregkh-2.6/drivers/usb/core/hub.c @@ -1234,7 +1234,7 @@ void usb_disconnect(struct usb_device ** if (udev->parent) { usb_pm_lock(udev); if (!udev->discon_suspended) - usb_autosuspend_device(udev->parent, 1); + usb_autosuspend_device(udev->parent); usb_pm_unlock(udev); } @@ -1368,7 +1368,7 @@ static int __usb_new_device(void *void_d /* Increment the parent's count of unsuspended children */ if (udev->parent) - usb_autoresume_device(udev->parent, 1); + usb_autoresume_device(udev->parent); exit: module_put(THIS_MODULE); @@ -1881,12 +1881,12 @@ static int remote_wakeup(struct usb_devi usb_lock_device(udev); if (udev->state == USB_STATE_SUSPENDED) { dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-"); - status = usb_autoresume_device(udev, 1); + status = usb_autoresume_device(udev); /* Give the interface drivers a chance to do something, * then autosuspend the device again. */ if (status == 0) - usb_autosuspend_device(udev, 1); + usb_autosuspend_device(udev); } usb_unlock_device(udev); return status; @@ -3099,7 +3099,7 @@ int usb_reset_composite_device(struct us } /* Prevent autosuspend during the reset */ - usb_autoresume_device(udev, 1); + usb_autoresume_device(udev); if (iface && iface->condition != USB_INTERFACE_BINDING) iface = NULL; @@ -3142,7 +3142,7 @@ int usb_reset_composite_device(struct us } } - usb_autosuspend_device(udev, 1); + usb_autosuspend_device(udev); return ret; } EXPORT_SYMBOL(usb_reset_composite_device); --- gregkh-2.6.orig/drivers/usb/core/message.c +++ gregkh-2.6/drivers/usb/core/message.c @@ -1398,7 +1398,7 @@ free_interfaces: } /* Wake up the device so we can send it the Set-Config request */ - ret = usb_autoresume_device(dev, 1); + ret = usb_autoresume_device(dev); if (ret) goto free_interfaces; @@ -1421,7 +1421,7 @@ free_interfaces: dev->actconfig = cp; if (!cp) { usb_set_device_state(dev, USB_STATE_ADDRESS); - usb_autosuspend_device(dev, 1); + usb_autosuspend_device(dev); goto free_interfaces; } usb_set_device_state(dev, USB_STATE_CONFIGURED); @@ -1490,7 +1490,7 @@ free_interfaces: usb_create_sysfs_intf_files (intf); } - usb_autosuspend_device(dev, 1); + usb_autosuspend_device(dev); return 0; } --- gregkh-2.6.orig/drivers/usb/core/usb.h +++ gregkh-2.6/drivers/usb/core/usb.h @@ -64,14 +64,13 @@ static inline void usb_pm_unlock(struct #define USB_AUTOSUSPEND_DELAY (HZ*2) -extern void usb_autosuspend_device(struct usb_device *udev, int dec_busy_cnt); -extern int usb_autoresume_device(struct usb_device *udev, int inc_busy_cnt); +extern void usb_autosuspend_device(struct usb_device *udev); +extern int usb_autoresume_device(struct usb_device *udev); #else -#define usb_autosuspend_device(udev, dec_busy_cnt) do {} while (0) -static inline int usb_autoresume_device(struct usb_device *udev, - int inc_busy_cnt) +#define usb_autosuspend_device(udev) do {} while (0) +static inline int usb_autoresume_device(struct usb_device *udev) { return 0; }