lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

USB: prepare for changover to Runtime PM framework

Browse Source 
This patch (as1303) revises the USB Power Management infrastructure to
make it compatible with the new driver-model Runtime PM framework:

	Drivers are no longer allowed to access intf->pm_usage_cnt
	directly; the PM framework manages its own usage counters.

	usb_autopm_set_interface() is eliminated, because it directly
	sets intf->pm_usage_cnt.

	usb_autopm_enable() and usb_autopm_disable() are eliminated,
	because they call usb_autopm_set_interface().

	usb_autopm_get_interface_no_resume() and
	usb_autopm_put_interface_no_suspend() are added.  They
	correspond to pm_runtime_get_noresume() and
	pm_runtime_put_noidle() in the PM framework.

	The power/level attribute no longer accepts "suspend", only
	"on" and "auto".  The PM framework doesn't allow devices to be
	forced into a suspended mode.

The hub driver contains the only code that violates the new
guidelines.  It is updated to use the new interface routines instead.

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
2009-12-07 13:01:37 -05:00
committed by Greg Kroah-Hartman
parent 9af23624ae
commit 8e4ceb38eb
5 changed files with 74 additions and 113 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
drivers/usb/core/driver.c
View File

@@ -948,8 +948,6 @@ static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
done:
dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
if (status == 0)
udev->autoresume_disabled = 0;
return status;
}
@@ -1280,11 +1278,6 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
/* Propagate the resume up the tree, if necessary */
if (udev->state == USB_STATE_SUSPENDED) {
if ((msg.event & PM_EVENT_AUTO) &&
udev->autoresume_disabled) {
status = -EPERM;
goto done;
}
if (parent) {
status = usb_autoresume_device(parent);
if (status == 0) {
@@ -1638,8 +1631,6 @@ int usb_autopm_get_interface_async(struct usb_interface *intf)
if (intf->condition == USB_INTERFACE_UNBOUND)
status = -ENODEV;
else if (udev->autoresume_disabled)
status = -EPERM;
else {
atomic_inc(&intf->pm_usage_cnt);
if (atomic_read(&intf->pm_usage_cnt) > 0 &&
@@ -1652,28 +1643,6 @@ int usb_autopm_get_interface_async(struct usb_interface *intf)
}
EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
/**
* usb_autopm_set_interface - set a USB interface's autosuspend state
* @intf: the usb_interface whose state should be set
*
* This routine sets the autosuspend state of @intf's device according
* to @intf's usage counter, which the caller must have set previously.
* If the counter is <= 0, the device is autosuspended (if it isn't
* already suspended and if nothing else prevents the autosuspend). If
* the counter is > 0, the device is autoresumed (if it isn't already
* awake).
*/
int usb_autopm_set_interface(struct usb_interface *intf)
{
int status;
status = usb_autopm_do_interface(intf, 0);
dev_vdbg(&intf->dev, "%s: status %d cnt %d\n",
__func__, status, atomic_read(&intf->pm_usage_cnt));
return status;
}
EXPORT_SYMBOL_GPL(usb_autopm_set_interface);
#else
void usb_autosuspend_work(struct work_struct *work)

45
drivers/usb/core/hub.c
View File

@@ -71,6 +71,7 @@ struct usb_hub {
unsigned mA_per_port; /* current for each child */
unsigned init_done:1;
unsigned limited_power:1;
unsigned quiescing:1;
unsigned disconnected:1;
@@ -375,12 +376,13 @@ static void kick_khubd(struct usb_hub *hub)
{
unsigned long flags;
/* Suppress autosuspend until khubd runs */
atomic_set(&to_usb_interface(hub->intfdev)->pm_usage_cnt, 1);
spin_lock_irqsave(&hub_event_lock, flags);
if (!hub->disconnected && list_empty(&hub->event_list)) {
list_add_tail(&hub->event_list, &hub_event_list);
/* Suppress autosuspend until khubd runs */
usb_autopm_get_interface_no_resume(
to_usb_interface(hub->intfdev));
wake_up(&khubd_wait);
}
spin_unlock_irqrestore(&hub_event_lock, flags);
@@ -665,7 +667,7 @@ int usb_remove_device(struct usb_device *udev)
}
enum hub_activation_type {
HUB_INIT, HUB_INIT2, HUB_INIT3,
HUB_INIT, HUB_INIT2, HUB_INIT3, /* INITs must come first */
HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
};
@@ -710,8 +712,8 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
msecs_to_jiffies(delay));
/* Suppress autosuspend until init is done */
atomic_set(&to_usb_interface(hub->intfdev)->
pm_usage_cnt, 1);
usb_autopm_get_interface_no_resume(
to_usb_interface(hub->intfdev));
return; /* Continues at init2: below */
} else {
hub_power_on(hub, true);
@@ -818,6 +820,7 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
}
init3:
hub->quiescing = 0;
hub->init_done = 1;
status = usb_submit_urb(hub->urb, GFP_NOIO);
if (status < 0)
@@ -827,6 +830,10 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
/* Scan all ports that need attention */
kick_khubd(hub);
/* Allow autosuspend if it was suppressed */
if (type <= HUB_INIT3)
usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
}
/* Implement the continuations for the delays above */
@@ -854,6 +861,11 @@ static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
int i;
cancel_delayed_work_sync(&hub->init_work);
if (!hub->init_done) {
hub->init_done = 1;
usb_autopm_put_interface_no_suspend(
to_usb_interface(hub->intfdev));
}
/* khubd and related activity won't re-trigger */
hub->quiescing = 1;
@@ -1176,7 +1188,10 @@ static void hub_disconnect(struct usb_interface *intf)
/* Take the hub off the event list and don't let it be added again */
spin_lock_irq(&hub_event_lock);
list_del_init(&hub->event_list);
if (!list_empty(&hub->event_list)) {
list_del_init(&hub->event_list);
usb_autopm_put_interface_no_suspend(intf);
}
hub->disconnected = 1;
spin_unlock_irq(&hub_event_lock);
@@ -3235,7 +3250,7 @@ static void hub_events(void)
* disconnected while waiting for the lock to succeed. */
usb_lock_device(hdev);
if (unlikely(hub->disconnected))
goto loop;
goto loop2;
/* If the hub has died, clean up after it */
if (hdev->state == USB_STATE_NOTATTACHED) {
@@ -3384,11 +3399,15 @@ static void hub_events(void)
}
}
loop_autopm:
/* Allow autosuspend if we're not going to run again */
if (list_empty(&hub->event_list))
usb_autopm_enable(intf);
loop:
loop_autopm:
/* Balance the usb_autopm_get_interface() above */
usb_autopm_put_interface_no_suspend(intf);
loop:
/* Balance the usb_autopm_get_interface_no_resume() in
* kick_khubd() and allow autosuspend.
*/
usb_autopm_put_interface(intf);
loop2:
usb_unlock_device(hdev);
kref_put(&hub->kref, hub_release);

25
drivers/usb/core/sysfs.c
View File

@@ -327,7 +327,6 @@ static DEVICE_ATTR(autosuspend, S_IRUGO | S_IWUSR,
static const char on_string[] = "on";
static const char auto_string[] = "auto";
static const char suspend_string[] = "suspend";
static ssize_t
show_level(struct device *dev, struct device_attribute *attr, char *buf)
@@ -335,13 +334,8 @@ show_level(struct device *dev, struct device_attribute *attr, char *buf)
struct usb_device *udev = to_usb_device(dev);
const char *p = auto_string;
if (udev->state == USB_STATE_SUSPENDED) {
if (udev->autoresume_disabled)
p = suspend_string;
} else {
if (udev->autosuspend_disabled)
p = on_string;
}
if (udev->state != USB_STATE_SUSPENDED && udev->autosuspend_disabled)
p = on_string;
return sprintf(buf, "%s\n", p);
}
@@ -353,7 +347,7 @@ set_level(struct device *dev, struct device_attribute *attr,
int len = count;
char *cp;
int rc = 0;
int old_autosuspend_disabled, old_autoresume_disabled;
int old_autosuspend_disabled;
cp = memchr(buf, '\n', count);
if (cp)
@@ -361,7 +355,6 @@ set_level(struct device *dev, struct device_attribute *attr,
usb_lock_device(udev);
old_autosuspend_disabled = udev->autosuspend_disabled;
old_autoresume_disabled = udev->autoresume_disabled;
/* Setting the flags without calling usb_pm_lock is a subject to
* races, but who cares...
@@ -369,28 +362,18 @@ set_level(struct device *dev, struct device_attribute *attr,
if (len == sizeof on_string - 1 &&
strncmp(buf, on_string, len) == 0) {
udev->autosuspend_disabled = 1;
udev->autoresume_disabled = 0;
rc = usb_external_resume_device(udev, PMSG_USER_RESUME);
} else if (len == sizeof auto_string - 1 &&
strncmp(buf, auto_string, len) == 0) {
udev->autosuspend_disabled = 0;
udev->autoresume_disabled = 0;
rc = usb_external_resume_device(udev, PMSG_USER_RESUME);
} else if (len == sizeof suspend_string - 1 &&
strncmp(buf, suspend_string, len) == 0) {
udev->autosuspend_disabled = 0;
udev->autoresume_disabled = 1;
rc = usb_external_suspend_device(udev, PMSG_USER_SUSPEND);
} else
rc = -EINVAL;
if (rc) {
if (rc)
udev->autosuspend_disabled = old_autosuspend_disabled;
udev->autoresume_disabled = old_autoresume_disabled;
}
usb_unlock_device(udev);
return (rc < 0 ? rc : count);
}