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path: root/drivers/usb/core/urb.c
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Diffstat (limited to 'drivers/usb/core/urb.c')
-rw-r--r--drivers/usb/core/urb.c71
1 files changed, 54 insertions, 17 deletions
diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index c12bc790a6a..991386ceb4e 100644
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -2,7 +2,6 @@
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/slab.h>
-#include <linux/init.h>
#include <linux/log2.h>
#include <linux/usb.h>
#include <linux/wait.h>
@@ -53,7 +52,7 @@ EXPORT_SYMBOL_GPL(usb_init_urb);
* valid options for this.
*
* Creates an urb for the USB driver to use, initializes a few internal
- * structures, incrementes the usage counter, and returns a pointer to it.
+ * structures, increments the usage counter, and returns a pointer to it.
*
* If the driver want to use this urb for interrupt, control, or bulk
* endpoints, pass '0' as the number of iso packets.
@@ -138,13 +137,19 @@ void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor)
}
EXPORT_SYMBOL_GPL(usb_anchor_urb);
+static int usb_anchor_check_wakeup(struct usb_anchor *anchor)
+{
+ return atomic_read(&anchor->suspend_wakeups) == 0 &&
+ list_empty(&anchor->urb_list);
+}
+
/* Callers must hold anchor->lock */
static void __usb_unanchor_urb(struct urb *urb, struct usb_anchor *anchor)
{
urb->anchor = NULL;
list_del(&urb->anchor_list);
usb_put_urb(urb);
- if (list_empty(&anchor->urb_list))
+ if (usb_anchor_check_wakeup(anchor))
wake_up(&anchor->wait);
}
@@ -275,7 +280,7 @@ EXPORT_SYMBOL_GPL(usb_unanchor_urb);
*
* Device drivers must explicitly request that repetition, by ensuring that
* some URB is always on the endpoint's queue (except possibly for short
- * periods during completion callacks). When there is no longer an urb
+ * periods during completion callbacks). When there is no longer an urb
* queued, the endpoint's bandwidth reservation is canceled. This means
* drivers can use their completion handlers to ensure they keep bandwidth
* they need, by reinitializing and resubmitting the just-completed urb
@@ -319,10 +324,14 @@ EXPORT_SYMBOL_GPL(usb_unanchor_urb);
*/
int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
{
+ static int pipetypes[4] = {
+ PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
+ };
int xfertype, max;
struct usb_device *dev;
struct usb_host_endpoint *ep;
int is_out;
+ unsigned int allowed;
if (!urb || !urb->complete)
return -EINVAL;
@@ -430,15 +439,10 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
if (urb->transfer_buffer_length > INT_MAX)
return -EMSGSIZE;
-#ifdef DEBUG
- /* stuff that drivers shouldn't do, but which shouldn't
+ /*
+ * stuff that drivers shouldn't do, but which shouldn't
* cause problems in HCDs if they get it wrong.
*/
- {
- unsigned int allowed;
- static int pipetypes[4] = {
- PIPE_CONTROL, PIPE_ISOCHRONOUS, PIPE_BULK, PIPE_INTERRUPT
- };
/* Check that the pipe's type matches the endpoint's type */
if (usb_pipetype(urb->pipe) != pipetypes[xfertype])
@@ -470,8 +474,7 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
if (allowed != urb->transfer_flags)
dev_WARN(&dev->dev, "BOGUS urb flags, %x --> %x\n",
urb->transfer_flags, allowed);
- }
-#endif
+
/*
* Force periodic transfer intervals to be legal values that are
* a power of two (so HCDs don't need to).
@@ -486,9 +489,9 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
/* too small? */
switch (dev->speed) {
case USB_SPEED_WIRELESS:
- if (urb->interval < 6)
+ if ((urb->interval < 6)
+ && (xfertype == USB_ENDPOINT_XFER_INT))
return -EINVAL;
- break;
default:
if (urb->interval <= 0)
return -EINVAL;
@@ -828,7 +831,7 @@ EXPORT_SYMBOL_GPL(usb_unpoison_anchored_urbs);
*
* this allows all outstanding URBs to be unlinked starting
* from the back of the queue. This function is asynchronous.
- * The unlinking is just tiggered. It may happen after this
+ * The unlinking is just triggered. It may happen after this
* function has returned.
*
* This routine should not be called by a driver after its disconnect
@@ -846,6 +849,39 @@ void usb_unlink_anchored_urbs(struct usb_anchor *anchor)
EXPORT_SYMBOL_GPL(usb_unlink_anchored_urbs);
/**
+ * usb_anchor_suspend_wakeups
+ * @anchor: the anchor you want to suspend wakeups on
+ *
+ * Call this to stop the last urb being unanchored from waking up any
+ * usb_wait_anchor_empty_timeout waiters. This is used in the hcd urb give-
+ * back path to delay waking up until after the completion handler has run.
+ */
+void usb_anchor_suspend_wakeups(struct usb_anchor *anchor)
+{
+ if (anchor)
+ atomic_inc(&anchor->suspend_wakeups);
+}
+EXPORT_SYMBOL_GPL(usb_anchor_suspend_wakeups);
+
+/**
+ * usb_anchor_resume_wakeups
+ * @anchor: the anchor you want to resume wakeups on
+ *
+ * Allow usb_wait_anchor_empty_timeout waiters to be woken up again, and
+ * wake up any current waiters if the anchor is empty.
+ */
+void usb_anchor_resume_wakeups(struct usb_anchor *anchor)
+{
+ if (!anchor)
+ return;
+
+ atomic_dec(&anchor->suspend_wakeups);
+ if (usb_anchor_check_wakeup(anchor))
+ wake_up(&anchor->wait);
+}
+EXPORT_SYMBOL_GPL(usb_anchor_resume_wakeups);
+
+/**
* usb_wait_anchor_empty_timeout - wait for an anchor to be unused
* @anchor: the anchor you want to become unused
* @timeout: how long you are willing to wait in milliseconds
@@ -858,7 +894,8 @@ EXPORT_SYMBOL_GPL(usb_unlink_anchored_urbs);
int usb_wait_anchor_empty_timeout(struct usb_anchor *anchor,
unsigned int timeout)
{
- return wait_event_timeout(anchor->wait, list_empty(&anchor->urb_list),
+ return wait_event_timeout(anchor->wait,
+ usb_anchor_check_wakeup(anchor),
msecs_to_jiffies(timeout));
}
EXPORT_SYMBOL_GPL(usb_wait_anchor_empty_timeout);