USB: make intf.pm_usage an atomic_t
This patch (as1260) changes the pm_usage_cnt field in struct
usb_interface from an int to an atomic_t. This is so that drivers can
invoke the usb_autopm_get_interface_async() and
usb_autopm_put_interface_async() routines without locking and without
fear of corrupting the pm_usage_cnt value.
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 cb54420..69e3a96 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -373,7 +373,7 @@
unsigned long flags;
/* Suppress autosuspend until khubd runs */
- to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
+ 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)) {
@@ -678,7 +678,8 @@
msecs_to_jiffies(delay));
/* Suppress autosuspend until init is done */
- to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
+ atomic_set(&to_usb_interface(hub->intfdev)->
+ pm_usage_cnt, 1);
return; /* Continues at init2: below */
} else {
hub_power_on(hub, true);