diff options
Diffstat (limited to 'drivers/usb/wusbcore')
| -rw-r--r-- | drivers/usb/wusbcore/wa-hc.h | 10 | ||||
| -rw-r--r-- | drivers/usb/wusbcore/wa-rpipe.c | 9 | ||||
| -rw-r--r-- | drivers/usb/wusbcore/wa-xfer.c | 154 |
3 files changed, 152 insertions, 21 deletions
diff --git a/drivers/usb/wusbcore/wa-hc.h b/drivers/usb/wusbcore/wa-hc.h index b44aca3..41afaa6 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 554b16b..50de1d2 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 fd00e1a..f1e9a38 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; } |
