USB: Add autosuspend support to the hub driver
This patch (as742b) adds autosuspend/autoresume support to the USB hub
driver. The largest aspect of the change is that we no longer need a
special flag for root hubs that want to be resumed. Now every hub is
autoresumed whenever khubd needs to access it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index f6e6921..55812a5 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -65,7 +65,6 @@
unsigned limited_power:1;
unsigned quiescing:1;
unsigned activating:1;
- unsigned resume_root_hub:1;
unsigned has_indicators:1;
u8 indicator[USB_MAXCHILDREN];
@@ -328,6 +327,9 @@
{
unsigned long flags;
+ /* Suppress autosuspend until khubd runs */
+ to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
+
spin_lock_irqsave(&hub_event_lock, flags);
if (list_empty(&hub->event_list)) {
list_add_tail(&hub->event_list, &hub_event_list);
@@ -509,7 +511,6 @@
/* (nonblocking) khubd and related activity won't re-trigger */
hub->quiescing = 1;
hub->activating = 0;
- hub->resume_root_hub = 0;
/* (blocking) stop khubd and related activity */
usb_kill_urb(hub->urb);
@@ -525,7 +526,7 @@
hub->quiescing = 0;
hub->activating = 1;
- hub->resume_root_hub = 0;
+
status = usb_submit_urb(hub->urb, GFP_NOIO);
if (status < 0)
dev_err(hub->intfdev, "activate --> %d\n", status);
@@ -940,6 +941,7 @@
INIT_WORK(&hub->leds, led_work, hub);
usb_set_intfdata (intf, hub);
+ intf->needs_remote_wakeup = 1;
if (hdev->speed == USB_SPEED_HIGH)
highspeed_hubs++;
@@ -1938,6 +1940,8 @@
}
}
+ dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
+
/* "global suspend" of the downstream HC-to-USB interface */
if (!hdev->parent) {
struct usb_bus *bus = hdev->bus;
@@ -1960,10 +1964,12 @@
static int hub_resume(struct usb_interface *intf)
{
- struct usb_device *hdev = interface_to_usbdev(intf);
struct usb_hub *hub = usb_get_intfdata (intf);
+ struct usb_device *hdev = hub->hdev;
int status;
+ dev_dbg(&intf->dev, "%s\n", __FUNCTION__);
+
/* "global resume" of the downstream HC-to-USB interface */
if (!hdev->parent) {
struct usb_bus *bus = hdev->bus;
@@ -2002,7 +2008,6 @@
{
struct usb_hub *hub = hdev_to_hub(hdev);
- hub->resume_root_hub = 1;
kick_khubd(hub);
}
@@ -2639,16 +2644,13 @@
intf = to_usb_interface(hub->intfdev);
hub_dev = &intf->dev;
- i = hub->resume_root_hub;
-
- dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
+ dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
hdev->state, hub->descriptor
? hub->descriptor->bNbrPorts
: 0,
/* NOTE: expects max 15 ports... */
(u16) hub->change_bits[0],
- (u16) hub->event_bits[0],
- i ? ", resume root" : "");
+ (u16) hub->event_bits[0]);
usb_get_intf(intf);
spin_unlock_irq(&hub_event_lock);
@@ -2669,16 +2671,16 @@
goto loop;
}
- /* Is this is a root hub wanting to reactivate the downstream
- * ports? If so, be sure the interface resumes even if its
- * stub "device" node was never suspended.
- */
- if (i)
- usb_autoresume_device(hdev, 0);
-
- /* If this is an inactive or suspended hub, do nothing */
- if (hub->quiescing)
+ /* Autoresume */
+ ret = usb_autopm_get_interface(intf);
+ if (ret) {
+ dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
goto loop;
+ }
+
+ /* If this is an inactive hub, do nothing */
+ if (hub->quiescing)
+ goto loop_autopm;
if (hub->error) {
dev_dbg (hub_dev, "resetting for error %d\n",
@@ -2688,7 +2690,7 @@
if (ret) {
dev_dbg (hub_dev,
"error resetting hub: %d\n", ret);
- goto loop;
+ goto loop_autopm;
}
hub->nerrors = 0;
@@ -2816,6 +2818,10 @@
if (!hdev->parent && !hub->busy_bits[0])
usb_enable_root_hub_irq(hdev->bus);
+loop_autopm:
+ /* Allow autosuspend if we're not going to run again */
+ if (list_empty(&hub->event_list))
+ usb_autopm_enable(intf);
loop:
usb_unlock_device(hdev);
usb_put_intf(intf);
@@ -2857,6 +2863,7 @@
.post_reset = hub_post_reset,
.ioctl = hub_ioctl,
.id_table = hub_id_table,
+ .supports_autosuspend = 1,
};
int usb_hub_init(void)