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-rw-r--r--drivers/usb/wusbcore/wa-hc.h10
-rw-r--r--drivers/usb/wusbcore/wa-rpipe.c9
-rw-r--r--drivers/usb/wusbcore/wa-xfer.c154
3 files changed, 152 insertions, 21 deletions
diff --git a/drivers/usb/wusbcore/wa-hc.h b/drivers/usb/wusbcore/wa-hc.h
index b44aca3f25dd..41afaa6d01d2 100644
--- a/drivers/usb/wusbcore/wa-hc.h
+++ b/drivers/usb/wusbcore/wa-hc.h
@@ -117,6 +117,7 @@ struct wa_rpipe {
struct wahc *wa;
spinlock_t seg_lock;
struct list_head seg_list;
+ struct list_head list_node;
atomic_t segs_available;
u8 buffer[1]; /* For reads/writes on USB */
};
@@ -183,7 +184,8 @@ struct wahc {
u16 rpipes;
unsigned long *rpipe_bm; /* rpipe usage bitmap */
- spinlock_t rpipe_bm_lock; /* protect rpipe_bm */
+ struct list_head rpipe_delayed_list; /* delayed RPIPES. */
+ spinlock_t rpipe_lock; /* protect rpipe_bm and delayed list */
struct mutex rpipe_mutex; /* assigning resources to endpoints */
/*
@@ -201,6 +203,8 @@ struct wahc {
void *dti_buf;
size_t dti_buf_size;
+ unsigned long dto_in_use; /* protect dto endoint serialization. */
+
s32 status; /* For reading status */
struct list_head xfer_list;
@@ -253,7 +257,8 @@ static inline void wa_nep_disarm(struct wahc *wa)
/* RPipes */
static inline void wa_rpipe_init(struct wahc *wa)
{
- spin_lock_init(&wa->rpipe_bm_lock);
+ INIT_LIST_HEAD(&wa->rpipe_delayed_list);
+ spin_lock_init(&wa->rpipe_lock);
mutex_init(&wa->rpipe_mutex);
}
@@ -270,6 +275,7 @@ static inline void wa_init(struct wahc *wa)
spin_lock_init(&wa->xfer_list_lock);
INIT_WORK(&wa->xfer_enqueue_work, wa_urb_enqueue_run);
INIT_WORK(&wa->xfer_error_work, wa_process_errored_transfers_run);
+ wa->dto_in_use = 0;
atomic_set(&wa->xfer_id_count, 1);
}
diff --git a/drivers/usb/wusbcore/wa-rpipe.c b/drivers/usb/wusbcore/wa-rpipe.c
index 554b16bd22f1..50de1d2c7b72 100644
--- a/drivers/usb/wusbcore/wa-rpipe.c
+++ b/drivers/usb/wusbcore/wa-rpipe.c
@@ -143,17 +143,18 @@ static void rpipe_init(struct wa_rpipe *rpipe)
kref_init(&rpipe->refcnt);
spin_lock_init(&rpipe->seg_lock);
INIT_LIST_HEAD(&rpipe->seg_list);
+ INIT_LIST_HEAD(&rpipe->list_node);
}
static unsigned rpipe_get_idx(struct wahc *wa, unsigned rpipe_idx)
{
unsigned long flags;
- spin_lock_irqsave(&wa->rpipe_bm_lock, flags);
+ spin_lock_irqsave(&wa->rpipe_lock, flags);
rpipe_idx = find_next_zero_bit(wa->rpipe_bm, wa->rpipes, rpipe_idx);
if (rpipe_idx < wa->rpipes)
set_bit(rpipe_idx, wa->rpipe_bm);
- spin_unlock_irqrestore(&wa->rpipe_bm_lock, flags);
+ spin_unlock_irqrestore(&wa->rpipe_lock, flags);
return rpipe_idx;
}
@@ -162,9 +163,9 @@ static void rpipe_put_idx(struct wahc *wa, unsigned rpipe_idx)
{
unsigned long flags;
- spin_lock_irqsave(&wa->rpipe_bm_lock, flags);
+ spin_lock_irqsave(&wa->rpipe_lock, flags);
clear_bit(rpipe_idx, wa->rpipe_bm);
- spin_unlock_irqrestore(&wa->rpipe_bm_lock, flags);
+ spin_unlock_irqrestore(&wa->rpipe_lock, flags);
}
void rpipe_destroy(struct kref *_rpipe)
diff --git a/drivers/usb/wusbcore/wa-xfer.c b/drivers/usb/wusbcore/wa-xfer.c
index fd00e1aaccf4..f1e9a386beca 100644
--- a/drivers/usb/wusbcore/wa-xfer.c
+++ b/drivers/usb/wusbcore/wa-xfer.c
@@ -107,6 +107,7 @@ enum wa_seg_status {
};
static void wa_xfer_delayed_run(struct wa_rpipe *);
+static int __wa_xfer_delayed_run(struct wa_rpipe *rpipe, int *dto_waiting);
/*
* Life cycle governed by 'struct urb' (the refcount of the struct is
@@ -204,6 +205,59 @@ static void wa_xfer_put(struct wa_xfer *xfer)
}
/*
+ * Try to get exclusive access to the DTO endpoint resource. Return true
+ * if successful.
+ */
+static inline int __wa_dto_try_get(struct wahc *wa)
+{
+ return (test_and_set_bit(0, &wa->dto_in_use) == 0);
+}
+
+/* Release the DTO endpoint resource. */
+static inline void __wa_dto_put(struct wahc *wa)
+{
+ clear_bit_unlock(0, &wa->dto_in_use);
+}
+
+/* Service RPIPEs that are waiting on the DTO resource. */
+static void wa_check_for_delayed_rpipes(struct wahc *wa)
+{
+ unsigned long flags;
+ int dto_waiting = 0;
+ struct wa_rpipe *rpipe;
+
+ spin_lock_irqsave(&wa->rpipe_lock, flags);
+ while (!list_empty(&wa->rpipe_delayed_list) && !dto_waiting) {
+ rpipe = list_first_entry(&wa->rpipe_delayed_list,
+ struct wa_rpipe, list_node);
+ __wa_xfer_delayed_run(rpipe, &dto_waiting);
+ /* remove this RPIPE from the list if it is not waiting. */
+ if (!dto_waiting) {
+ pr_debug("%s: RPIPE %d serviced and removed from delayed list.\n",
+ __func__,
+ le16_to_cpu(rpipe->descr.wRPipeIndex));
+ list_del_init(&rpipe->list_node);
+ }
+ }
+ spin_unlock_irqrestore(&wa->rpipe_lock, flags);
+}
+
+/* add this RPIPE to the end of the delayed RPIPE list. */
+static void wa_add_delayed_rpipe(struct wahc *wa, struct wa_rpipe *rpipe)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&wa->rpipe_lock, flags);
+ /* add rpipe to the list if it is not already on it. */
+ if (list_empty(&rpipe->list_node)) {
+ pr_debug("%s: adding RPIPE %d to the delayed list.\n",
+ __func__, le16_to_cpu(rpipe->descr.wRPipeIndex));
+ list_add_tail(&rpipe->list_node, &wa->rpipe_delayed_list);
+ }
+ spin_unlock_irqrestore(&wa->rpipe_lock, flags);
+}
+
+/*
* xfer is referenced
*
* xfer->lock has to be unlocked
@@ -1099,9 +1153,13 @@ error_setup_sizes:
* rpipe->seg_lock is held!
*/
static int __wa_seg_submit(struct wa_rpipe *rpipe, struct wa_xfer *xfer,
- struct wa_seg *seg)
+ struct wa_seg *seg, int *dto_done)
{
int result;
+
+ /* default to done unless we encounter a multi-frame isoc segment. */
+ *dto_done = 1;
+
/* submit the transfer request. */
result = usb_submit_urb(&seg->tr_urb, GFP_ATOMIC);
if (result < 0) {
@@ -1142,28 +1200,34 @@ error_seg_submit:
}
/*
- * Execute more queued request segments until the maximum concurrent allowed
+ * Execute more queued request segments until the maximum concurrent allowed.
+ * Return true if the DTO resource was acquired and released.
*
* The ugly unlock/lock sequence on the error path is needed as the
* xfer->lock normally nests the seg_lock and not viceversa.
- *
*/
-static void wa_xfer_delayed_run(struct wa_rpipe *rpipe)
+static int __wa_xfer_delayed_run(struct wa_rpipe *rpipe, int *dto_waiting)
{
- int result;
+ int result, dto_acquired = 0, dto_done = 0;
struct device *dev = &rpipe->wa->usb_iface->dev;
struct wa_seg *seg;
struct wa_xfer *xfer;
unsigned long flags;
+ *dto_waiting = 0;
+
spin_lock_irqsave(&rpipe->seg_lock, flags);
while (atomic_read(&rpipe->segs_available) > 0
- && !list_empty(&rpipe->seg_list)) {
+ && !list_empty(&rpipe->seg_list)
+ && (dto_acquired = __wa_dto_try_get(rpipe->wa))) {
seg = list_first_entry(&(rpipe->seg_list), struct wa_seg,
list_node);
list_del(&seg->list_node);
xfer = seg->xfer;
- result = __wa_seg_submit(rpipe, xfer, seg);
+ result = __wa_seg_submit(rpipe, xfer, seg, &dto_done);
+ /* release the dto resource if this RPIPE is done with it. */
+ if (dto_done)
+ __wa_dto_put(rpipe->wa);
dev_dbg(dev, "xfer %p ID %08X#%u submitted from delayed [%d segments available] %d\n",
xfer, wa_xfer_id(xfer), seg->index,
atomic_read(&rpipe->segs_available), result);
@@ -1176,7 +1240,37 @@ static void wa_xfer_delayed_run(struct wa_rpipe *rpipe)
spin_lock_irqsave(&rpipe->seg_lock, flags);
}
}
+ /*
+ * Mark this RPIPE as waiting if dto was not acquired, there are
+ * delayed segs and no active transfers to wake us up later.
+ */
+ if (!dto_acquired && !list_empty(&rpipe->seg_list)
+ && (atomic_read(&rpipe->segs_available) ==
+ le16_to_cpu(rpipe->descr.wRequests)))
+ *dto_waiting = 1;
+
spin_unlock_irqrestore(&rpipe->seg_lock, flags);
+
+ return dto_done;
+}
+
+static void wa_xfer_delayed_run(struct wa_rpipe *rpipe)
+{
+ int dto_waiting;
+ int dto_done = __wa_xfer_delayed_run(rpipe, &dto_waiting);
+
+ /*
+ * If this RPIPE is waiting on the DTO resource, add it to the tail of
+ * the waiting list.
+ * Otherwise, if the WA DTO resource was acquired and released by
+ * __wa_xfer_delayed_run, another RPIPE may have attempted to acquire
+ * DTO and failed during that time. Check the delayed list and process
+ * any waiters. Start searching from the next RPIPE index.
+ */
+ if (dto_waiting)
+ wa_add_delayed_rpipe(rpipe->wa, rpipe);
+ else if (dto_done)
+ wa_check_for_delayed_rpipes(rpipe->wa);
}
/*
@@ -1188,7 +1282,7 @@ static void wa_xfer_delayed_run(struct wa_rpipe *rpipe)
*/
static int __wa_xfer_submit(struct wa_xfer *xfer)
{
- int result;
+ int result, dto_acquired = 0, dto_done = 0, dto_waiting = 0;
struct wahc *wa = xfer->wa;
struct device *dev = &wa->usb_iface->dev;
unsigned cnt;
@@ -1207,26 +1301,56 @@ static int __wa_xfer_submit(struct wa_xfer *xfer)
result = 0;
spin_lock_irqsave(&rpipe->seg_lock, flags);
for (cnt = 0; cnt < xfer->segs; cnt++) {
+ int delay_seg = 1;
+
available = atomic_read(&rpipe->segs_available);
empty = list_empty(&rpipe->seg_list);
seg = xfer->seg[cnt];
dev_dbg(dev, "xfer %p ID 0x%08X#%u: available %u empty %u (%s)\n",
xfer, wa_xfer_id(xfer), cnt, available, empty,
available == 0 || !empty ? "delayed" : "submitted");
- if (available == 0 || !empty) {
+ if (available && empty) {
+ /*
+ * Only attempt to acquire DTO if we have a segment
+ * to send.
+ */
+ dto_acquired = __wa_dto_try_get(rpipe->wa);
+ if (dto_acquired) {
+ delay_seg = 0;
+ result = __wa_seg_submit(rpipe, xfer, seg,
+ &dto_done);
+ if (dto_done)
+ __wa_dto_put(rpipe->wa);
+
+ if (result < 0) {
+ __wa_xfer_abort(xfer);
+ goto error_seg_submit;
+ }
+ }
+ }
+
+ if (delay_seg) {
seg->status = WA_SEG_DELAYED;
list_add_tail(&seg->list_node, &rpipe->seg_list);
- } else {
- result = __wa_seg_submit(rpipe, xfer, seg);
- if (result < 0) {
- __wa_xfer_abort(xfer);
- goto error_seg_submit;
- }
}
xfer->segs_submitted++;
}
error_seg_submit:
+ /*
+ * Mark this RPIPE as waiting if dto was not acquired, there are
+ * delayed segs and no active transfers to wake us up later.
+ */
+ if (!dto_acquired && !list_empty(&rpipe->seg_list)
+ && (atomic_read(&rpipe->segs_available) ==
+ le16_to_cpu(rpipe->descr.wRequests)))
+ dto_waiting = 1;
spin_unlock_irqrestore(&rpipe->seg_lock, flags);
+
+ if (dto_waiting)
+ wa_add_delayed_rpipe(rpipe->wa, rpipe);
+ else if (dto_done)
+ wa_check_for_delayed_rpipes(rpipe->wa);
+
return result;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 20:29:47 +0000