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[~andy/linux] / drivers / staging / ozwpan / ozpd.c
1 /* -----------------------------------------------------------------------------
2  * Copyright (c) 2011 Ozmo Inc
3  * Released under the GNU General Public License Version 2 (GPLv2).
4  * -----------------------------------------------------------------------------
5  */
6 #include <linux/init.h>
7 #include <linux/module.h>
8 #include <linux/timer.h>
9 #include <linux/sched.h>
10 #include <linux/netdevice.h>
11 #include <linux/errno.h>
12 #include "ozconfig.h"
13 #include "ozprotocol.h"
14 #include "ozeltbuf.h"
15 #include "ozpd.h"
16 #include "ozproto.h"
17 #include "oztrace.h"
18 #include "ozevent.h"
19 #include "ozcdev.h"
20 #include "ozusbsvc.h"
21 #include <asm/unaligned.h>
22 #include <linux/uaccess.h>
23 #include <net/psnap.h>
24 /*------------------------------------------------------------------------------
25  */
26 #define OZ_MAX_TX_POOL_SIZE     6
27 /* Maximum number of uncompleted isoc frames that can be pending.
28  */
29 #define OZ_MAX_SUBMITTED_ISOC   16
30 /*------------------------------------------------------------------------------
31  */
32 static struct oz_tx_frame *oz_tx_frame_alloc(struct oz_pd *pd);
33 static void oz_tx_frame_free(struct oz_pd *pd, struct oz_tx_frame *f);
34 static struct sk_buff *oz_build_frame(struct oz_pd *pd, struct oz_tx_frame *f);
35 static int oz_send_isoc_frame(struct oz_pd *pd);
36 static void oz_retire_frame(struct oz_pd *pd, struct oz_tx_frame *f);
37 static void oz_isoc_stream_free(struct oz_isoc_stream *st);
38 static int oz_send_next_queued_frame(struct oz_pd *pd, int *more_data);
39 static void oz_isoc_destructor(struct sk_buff *skb);
40 static int oz_def_app_init(void);
41 static void oz_def_app_term(void);
42 static int oz_def_app_start(struct oz_pd *pd, int resume);
43 static void oz_def_app_stop(struct oz_pd *pd, int pause);
44 static void oz_def_app_rx(struct oz_pd *pd, struct oz_elt *elt);
45 /*------------------------------------------------------------------------------
46  * Counts the uncompleted isoc frames submitted to netcard.
47  */
48 static atomic_t g_submitted_isoc = ATOMIC_INIT(0);
49 /* Application handler functions.
50  */
51 static struct oz_app_if g_app_if[OZ_APPID_MAX] = {
52         {oz_usb_init,
53         oz_usb_term,
54         oz_usb_start,
55         oz_usb_stop,
56         oz_usb_rx,
57         oz_usb_heartbeat,
58         oz_usb_farewell,
59         OZ_APPID_USB},
60
61         {oz_def_app_init,
62         oz_def_app_term,
63         oz_def_app_start,
64         oz_def_app_stop,
65         oz_def_app_rx,
66         0,
67         0,
68         OZ_APPID_UNUSED1},
69
70         {oz_def_app_init,
71         oz_def_app_term,
72         oz_def_app_start,
73         oz_def_app_stop,
74         oz_def_app_rx,
75         0,
76         0,
77         OZ_APPID_UNUSED2},
78
79         {oz_cdev_init,
80         oz_cdev_term,
81         oz_cdev_start,
82         oz_cdev_stop,
83         oz_cdev_rx,
84         0,
85         0,
86         OZ_APPID_SERIAL},
87 };
88 /*------------------------------------------------------------------------------
89  * Context: process
90  */
91 static int oz_def_app_init(void)
92 {
93         return 0;
94 }
95 /*------------------------------------------------------------------------------
96  * Context: process
97  */
98 static void oz_def_app_term(void)
99 {
100 }
101 /*------------------------------------------------------------------------------
102  * Context: softirq
103  */
104 static int oz_def_app_start(struct oz_pd *pd, int resume)
105 {
106         return 0;
107 }
108 /*------------------------------------------------------------------------------
109  * Context: softirq
110  */
111 static void oz_def_app_stop(struct oz_pd *pd, int pause)
112 {
113 }
114 /*------------------------------------------------------------------------------
115  * Context: softirq
116  */
117 static void oz_def_app_rx(struct oz_pd *pd, struct oz_elt *elt)
118 {
119 }
120 /*------------------------------------------------------------------------------
121  * Context: softirq or process
122  */
123 void oz_pd_set_state(struct oz_pd *pd, unsigned state)
124 {
125         pd->state = state;
126         oz_event_log(OZ_EVT_PD_STATE, 0, 0, 0, state);
127 #ifdef WANT_TRACE
128         switch (state) {
129         case OZ_PD_S_IDLE:
130                 oz_trace("PD State: OZ_PD_S_IDLE\n");
131                 break;
132         case OZ_PD_S_CONNECTED:
133                 oz_trace("PD State: OZ_PD_S_CONNECTED\n");
134                 break;
135         case OZ_PD_S_STOPPED:
136                 oz_trace("PD State: OZ_PD_S_STOPPED\n");
137                 break;
138         case OZ_PD_S_SLEEP:
139                 oz_trace("PD State: OZ_PD_S_SLEEP\n");
140                 break;
141         }
142 #endif /* WANT_TRACE */
143 }
144 /*------------------------------------------------------------------------------
145  * Context: softirq or process
146  */
147 void oz_pd_get(struct oz_pd *pd)
148 {
149         atomic_inc(&pd->ref_count);
150 }
151 /*------------------------------------------------------------------------------
152  * Context: softirq or process
153  */
154 void oz_pd_put(struct oz_pd *pd)
155 {
156         if (atomic_dec_and_test(&pd->ref_count))
157                 oz_pd_destroy(pd);
158 }
159 /*------------------------------------------------------------------------------
160  * Context: softirq-serialized
161  */
162 struct oz_pd *oz_pd_alloc(u8 *mac_addr)
163 {
164         struct oz_pd *pd = kzalloc(sizeof(struct oz_pd), GFP_ATOMIC);
165         if (pd) {
166                 int i;
167                 atomic_set(&pd->ref_count, 2);
168                 for (i = 0; i < OZ_APPID_MAX; i++)
169                         spin_lock_init(&pd->app_lock[i]);
170                 pd->last_rx_pkt_num = 0xffffffff;
171                 oz_pd_set_state(pd, OZ_PD_S_IDLE);
172                 pd->max_tx_size = OZ_MAX_TX_SIZE;
173                 memcpy(pd->mac_addr, mac_addr, ETH_ALEN);
174                 if (0 != oz_elt_buf_init(&pd->elt_buff)) {
175                         kfree(pd);
176                         pd = 0;
177                 }
178                 spin_lock_init(&pd->tx_frame_lock);
179                 INIT_LIST_HEAD(&pd->tx_queue);
180                 INIT_LIST_HEAD(&pd->farewell_list);
181                 pd->last_sent_frame = &pd->tx_queue;
182                 spin_lock_init(&pd->stream_lock);
183                 INIT_LIST_HEAD(&pd->stream_list);
184         }
185         return pd;
186 }
187 /*------------------------------------------------------------------------------
188  * Context: softirq or process
189  */
190 void oz_pd_destroy(struct oz_pd *pd)
191 {
192         struct list_head *e;
193         struct oz_tx_frame *f;
194         struct oz_isoc_stream *st;
195         struct oz_farewell *fwell;
196         oz_trace("Destroying PD\n");
197         /* Delete any streams.
198          */
199         e = pd->stream_list.next;
200         while (e != &pd->stream_list) {
201                 st = container_of(e, struct oz_isoc_stream, link);
202                 e = e->next;
203                 oz_isoc_stream_free(st);
204         }
205         /* Free any queued tx frames.
206          */
207         e = pd->tx_queue.next;
208         while (e != &pd->tx_queue) {
209                 f = container_of(e, struct oz_tx_frame, link);
210                 e = e->next;
211                 oz_retire_frame(pd, f);
212         }
213         oz_elt_buf_term(&pd->elt_buff);
214         /* Free any farewells.
215          */
216         e = pd->farewell_list.next;
217         while (e != &pd->farewell_list) {
218                 fwell = container_of(e, struct oz_farewell, link);
219                 e = e->next;
220                 kfree(fwell);
221         }
222         /* Deallocate all frames in tx pool.
223          */
224         while (pd->tx_pool) {
225                 e = pd->tx_pool;
226                 pd->tx_pool = e->next;
227                 kfree(container_of(e, struct oz_tx_frame, link));
228         }
229         if (pd->net_dev)
230                 dev_put(pd->net_dev);
231         kfree(pd);
232 }
233 /*------------------------------------------------------------------------------
234  * Context: softirq-serialized
235  */
236 int oz_services_start(struct oz_pd *pd, u16 apps, int resume)
237 {
238         struct oz_app_if *ai;
239         int rc = 0;
240         oz_trace("oz_services_start(0x%x) resume(%d)\n", apps, resume);
241         for (ai = g_app_if; ai < &g_app_if[OZ_APPID_MAX]; ai++) {
242                 if (apps & (1<<ai->app_id)) {
243                         if (ai->start(pd, resume)) {
244                                 rc = -1;
245                                 oz_trace("Unabled to start service %d\n",
246                                         ai->app_id);
247                                 break;
248                         }
249                         oz_polling_lock_bh();
250                         pd->total_apps |= (1<<ai->app_id);
251                         if (resume)
252                                 pd->paused_apps &= ~(1<<ai->app_id);
253                         oz_polling_unlock_bh();
254                 }
255         }
256         return rc;
257 }
258 /*------------------------------------------------------------------------------
259  * Context: softirq or process
260  */
261 void oz_services_stop(struct oz_pd *pd, u16 apps, int pause)
262 {
263         struct oz_app_if *ai;
264         oz_trace("oz_stop_services(0x%x) pause(%d)\n", apps, pause);
265         for (ai = g_app_if; ai < &g_app_if[OZ_APPID_MAX]; ai++) {
266                 if (apps & (1<<ai->app_id)) {
267                         oz_polling_lock_bh();
268                         if (pause) {
269                                 pd->paused_apps |= (1<<ai->app_id);
270                         } else {
271                                 pd->total_apps &= ~(1<<ai->app_id);
272                                 pd->paused_apps &= ~(1<<ai->app_id);
273                         }
274                         oz_polling_unlock_bh();
275                         ai->stop(pd, pause);
276                 }
277         }
278 }
279 /*------------------------------------------------------------------------------
280  * Context: softirq
281  */
282 void oz_pd_heartbeat(struct oz_pd *pd, u16 apps)
283 {
284         struct oz_app_if *ai;
285         int more = 0;
286         for (ai = g_app_if; ai < &g_app_if[OZ_APPID_MAX]; ai++) {
287                 if (ai->heartbeat && (apps & (1<<ai->app_id))) {
288                         if (ai->heartbeat(pd))
289                                 more = 1;
290                 }
291         }
292         if (more)
293                 oz_pd_request_heartbeat(pd);
294         if (pd->mode & OZ_F_ISOC_ANYTIME) {
295                 int count = 8;
296                 while (count-- && (oz_send_isoc_frame(pd) >= 0))
297                         ;
298         }
299 }
300 /*------------------------------------------------------------------------------
301  * Context: softirq or process
302  */
303 void oz_pd_stop(struct oz_pd *pd)
304 {
305         u16 stop_apps = 0;
306         oz_trace("oz_pd_stop() State = 0x%x\n", pd->state);
307         oz_pd_indicate_farewells(pd);
308         oz_polling_lock_bh();
309         stop_apps = pd->total_apps;
310         pd->total_apps = 0;
311         pd->paused_apps = 0;
312         oz_polling_unlock_bh();
313         oz_services_stop(pd, stop_apps, 0);
314         oz_polling_lock_bh();
315         oz_pd_set_state(pd, OZ_PD_S_STOPPED);
316         /* Remove from PD list.*/
317         list_del(&pd->link);
318         oz_polling_unlock_bh();
319         oz_trace("pd ref count = %d\n", atomic_read(&pd->ref_count));
320         oz_timer_delete(pd, 0);
321         oz_pd_put(pd);
322 }
323 /*------------------------------------------------------------------------------
324  * Context: softirq
325  */
326 int oz_pd_sleep(struct oz_pd *pd)
327 {
328         int do_stop = 0;
329         u16 stop_apps = 0;
330         oz_polling_lock_bh();
331         if (pd->state & (OZ_PD_S_SLEEP | OZ_PD_S_STOPPED)) {
332                 oz_polling_unlock_bh();
333                 return 0;
334         }
335         if (pd->keep_alive_j && pd->session_id) {
336                 oz_pd_set_state(pd, OZ_PD_S_SLEEP);
337                 pd->pulse_time_j = jiffies + pd->keep_alive_j;
338                 oz_trace("Sleep Now %lu until %lu\n",
339                         jiffies, pd->pulse_time_j);
340         } else {
341                 do_stop = 1;
342         }
343         stop_apps = pd->total_apps;
344         oz_polling_unlock_bh();
345         if (do_stop) {
346                 oz_pd_stop(pd);
347         } else {
348                 oz_services_stop(pd, stop_apps, 1);
349                 oz_timer_add(pd, OZ_TIMER_STOP, jiffies + pd->keep_alive_j, 1);
350         }
351         return do_stop;
352 }
353 /*------------------------------------------------------------------------------
354  * Context: softirq
355  */
356 static struct oz_tx_frame *oz_tx_frame_alloc(struct oz_pd *pd)
357 {
358         struct oz_tx_frame *f = 0;
359         spin_lock_bh(&pd->tx_frame_lock);
360         if (pd->tx_pool) {
361                 f = container_of(pd->tx_pool, struct oz_tx_frame, link);
362                 pd->tx_pool = pd->tx_pool->next;
363                 pd->tx_pool_count--;
364         }
365         spin_unlock_bh(&pd->tx_frame_lock);
366         if (f == 0)
367                 f = kmalloc(sizeof(struct oz_tx_frame), GFP_ATOMIC);
368         if (f) {
369                 f->total_size = sizeof(struct oz_hdr);
370                 INIT_LIST_HEAD(&f->link);
371                 INIT_LIST_HEAD(&f->elt_list);
372         }
373         return f;
374 }
375 /*------------------------------------------------------------------------------
376  * Context: softirq or process
377  */
378 static void oz_tx_frame_free(struct oz_pd *pd, struct oz_tx_frame *f)
379 {
380         spin_lock_bh(&pd->tx_frame_lock);
381         if (pd->tx_pool_count < OZ_MAX_TX_POOL_SIZE) {
382                 f->link.next = pd->tx_pool;
383                 pd->tx_pool = &f->link;
384                 pd->tx_pool_count++;
385                 f = 0;
386         }
387         spin_unlock_bh(&pd->tx_frame_lock);
388         if (f)
389                 kfree(f);
390 }
391 /*------------------------------------------------------------------------------
392  * Context: softirq
393  */
394 int oz_prepare_frame(struct oz_pd *pd, int empty)
395 {
396         struct oz_tx_frame *f;
397         if ((pd->mode & OZ_MODE_MASK) != OZ_MODE_TRIGGERED)
398                 return -1;
399         if (pd->nb_queued_frames >= OZ_MAX_QUEUED_FRAMES)
400                 return -1;
401         if (!empty && !oz_are_elts_available(&pd->elt_buff))
402                 return -1;
403         f = oz_tx_frame_alloc(pd);
404         if (f == 0)
405                 return -1;
406         f->hdr.control =
407                 (OZ_PROTOCOL_VERSION<<OZ_VERSION_SHIFT) | OZ_F_ACK_REQUESTED;
408         ++pd->last_tx_pkt_num;
409         put_unaligned(cpu_to_le32(pd->last_tx_pkt_num), &f->hdr.pkt_num);
410         if (empty == 0) {
411                 oz_select_elts_for_tx(&pd->elt_buff, 0, &f->total_size,
412                         pd->max_tx_size, &f->elt_list);
413         }
414         spin_lock(&pd->tx_frame_lock);
415         list_add_tail(&f->link, &pd->tx_queue);
416         pd->nb_queued_frames++;
417         spin_unlock(&pd->tx_frame_lock);
418         return 0;
419 }
420 /*------------------------------------------------------------------------------
421  * Context: softirq-serialized
422  */
423 static struct sk_buff *oz_build_frame(struct oz_pd *pd, struct oz_tx_frame *f)
424 {
425         struct sk_buff *skb = 0;
426         struct net_device *dev = pd->net_dev;
427         struct oz_hdr *oz_hdr;
428         struct oz_elt *elt;
429         struct list_head *e;
430         /* Allocate skb with enough space for the lower layers as well
431          * as the space we need.
432          */
433         skb = alloc_skb(f->total_size + OZ_ALLOCATED_SPACE(dev), GFP_ATOMIC);
434         if (skb == 0)
435                 return 0;
436         /* Reserve the head room for lower layers.
437          */
438         skb_reserve(skb, LL_RESERVED_SPACE(dev));
439         skb_reset_network_header(skb);
440         skb->dev = dev;
441         skb->protocol = htons(OZ_ETHERTYPE);
442         if (dev_hard_header(skb, dev, OZ_ETHERTYPE, pd->mac_addr,
443                 dev->dev_addr, skb->len) < 0)
444                 goto fail;
445         /* Push the tail to the end of the area we are going to copy to.
446          */
447         oz_hdr = (struct oz_hdr *)skb_put(skb, f->total_size);
448         f->hdr.last_pkt_num = pd->trigger_pkt_num & OZ_LAST_PN_MASK;
449         memcpy(oz_hdr, &f->hdr, sizeof(struct oz_hdr));
450         /* Copy the elements into the frame body.
451          */
452         elt = (struct oz_elt *)(oz_hdr+1);
453         for (e = f->elt_list.next; e != &f->elt_list; e = e->next) {
454                 struct oz_elt_info *ei;
455                 ei = container_of(e, struct oz_elt_info, link);
456                 memcpy(elt, ei->data, ei->length);
457                 elt = oz_next_elt(elt);
458         }
459         return skb;
460 fail:
461         kfree_skb(skb);
462         return 0;
463 }
464 /*------------------------------------------------------------------------------
465  * Context: softirq or process
466  */
467 static void oz_retire_frame(struct oz_pd *pd, struct oz_tx_frame *f)
468 {
469         struct list_head *e;
470         struct oz_elt_info *ei;
471         e = f->elt_list.next;
472         while (e != &f->elt_list) {
473                 ei = container_of(e, struct oz_elt_info, link);
474                 e = e->next;
475                 list_del_init(&ei->link);
476                 if (ei->callback)
477                         ei->callback(pd, ei->context);
478                 spin_lock_bh(&pd->elt_buff.lock);
479                 oz_elt_info_free(&pd->elt_buff, ei);
480                 spin_unlock_bh(&pd->elt_buff.lock);
481         }
482         oz_tx_frame_free(pd, f);
483         if (pd->elt_buff.free_elts > pd->elt_buff.max_free_elts)
484                 oz_trim_elt_pool(&pd->elt_buff);
485 }
486 /*------------------------------------------------------------------------------
487  * Context: softirq-serialized
488  */
489 static int oz_send_next_queued_frame(struct oz_pd *pd, int *more_data)
490 {
491         struct sk_buff *skb;
492         struct oz_tx_frame *f;
493         struct list_head *e;
494         *more_data = 0;
495         spin_lock(&pd->tx_frame_lock);
496         e = pd->last_sent_frame->next;
497         if (e == &pd->tx_queue) {
498                 spin_unlock(&pd->tx_frame_lock);
499                 return -1;
500         }
501         pd->last_sent_frame = e;
502         if (e->next != &pd->tx_queue)
503                 *more_data = 1;
504         f = container_of(e, struct oz_tx_frame, link);
505         skb = oz_build_frame(pd, f);
506         spin_unlock(&pd->tx_frame_lock);
507         oz_trace2(OZ_TRACE_TX_FRAMES, "TX frame PN=0x%x\n", f->hdr.pkt_num);
508         if (skb) {
509                 oz_event_log(OZ_EVT_TX_FRAME,
510                         0,
511                         (((u16)f->hdr.control)<<8)|f->hdr.last_pkt_num,
512                         0, f->hdr.pkt_num);
513                 if (dev_queue_xmit(skb) < 0)
514                         return -1;
515         }
516         return 0;
517 }
518 /*------------------------------------------------------------------------------
519  * Context: softirq-serialized
520  */
521 void oz_send_queued_frames(struct oz_pd *pd, int backlog)
522 {
523         int more;
524         if (backlog <  OZ_MAX_QUEUED_FRAMES) {
525                 if (oz_send_next_queued_frame(pd, &more) >= 0) {
526                         while (more && oz_send_next_queued_frame(pd, &more))
527                                 ;
528                 } else {
529                         if (((pd->mode & OZ_F_ISOC_ANYTIME) == 0)
530                                 || (pd->isoc_sent == 0)) {
531                                 if (oz_prepare_frame(pd, 1) >= 0)
532                                         oz_send_next_queued_frame(pd, &more);
533                         }
534                 }
535         } else {
536                 oz_send_next_queued_frame(pd, &more);
537         }
538 }
539 /*------------------------------------------------------------------------------
540  * Context: softirq
541  */
542 static int oz_send_isoc_frame(struct oz_pd *pd)
543 {
544         struct sk_buff *skb = 0;
545         struct net_device *dev = pd->net_dev;
546         struct oz_hdr *oz_hdr;
547         struct oz_elt *elt;
548         struct list_head *e;
549         struct list_head list;
550         int total_size = sizeof(struct oz_hdr);
551         INIT_LIST_HEAD(&list);
552
553         oz_select_elts_for_tx(&pd->elt_buff, 1, &total_size,
554                 pd->max_tx_size, &list);
555         if (list.next == &list)
556                 return 0;
557         skb = alloc_skb(total_size + OZ_ALLOCATED_SPACE(dev), GFP_ATOMIC);
558         if (skb == 0) {
559                 oz_trace("Cannot alloc skb\n");
560                 oz_elt_info_free_chain(&pd->elt_buff, &list);
561                 return -1;
562         }
563         skb_reserve(skb, LL_RESERVED_SPACE(dev));
564         skb_reset_network_header(skb);
565         skb->dev = dev;
566         skb->protocol = htons(OZ_ETHERTYPE);
567         if (dev_hard_header(skb, dev, OZ_ETHERTYPE, pd->mac_addr,
568                 dev->dev_addr, skb->len) < 0) {
569                 kfree_skb(skb);
570                 return -1;
571         }
572         oz_hdr = (struct oz_hdr *)skb_put(skb, total_size);
573         oz_hdr->control = (OZ_PROTOCOL_VERSION<<OZ_VERSION_SHIFT) | OZ_F_ISOC;
574         oz_hdr->last_pkt_num = pd->trigger_pkt_num & OZ_LAST_PN_MASK;
575         elt = (struct oz_elt *)(oz_hdr+1);
576
577         for (e = list.next; e != &list; e = e->next) {
578                 struct oz_elt_info *ei;
579                 ei = container_of(e, struct oz_elt_info, link);
580                 memcpy(elt, ei->data, ei->length);
581                 elt = oz_next_elt(elt);
582         }
583         oz_event_log(OZ_EVT_TX_ISOC, 0, 0, 0, 0);
584         dev_queue_xmit(skb);
585         oz_elt_info_free_chain(&pd->elt_buff, &list);
586         return 0;
587 }
588 /*------------------------------------------------------------------------------
589  * Context: softirq-serialized
590  */
591 void oz_retire_tx_frames(struct oz_pd *pd, u8 lpn)
592 {
593         struct list_head *e;
594         struct oz_tx_frame *f;
595         struct list_head *first = 0;
596         struct list_head *last = 0;
597         u8 diff;
598         u32 pkt_num;
599
600         spin_lock(&pd->tx_frame_lock);
601         e = pd->tx_queue.next;
602         while (e != &pd->tx_queue) {
603                 f = container_of(e, struct oz_tx_frame, link);
604                 pkt_num = le32_to_cpu(get_unaligned(&f->hdr.pkt_num));
605                 diff = (lpn - (pkt_num & OZ_LAST_PN_MASK)) & OZ_LAST_PN_MASK;
606                 if (diff > OZ_LAST_PN_HALF_CYCLE)
607                         break;
608                 if (first == 0)
609                         first = e;
610                 last = e;
611                 e = e->next;
612                 pd->nb_queued_frames--;
613         }
614         if (first) {
615                 last->next->prev = &pd->tx_queue;
616                 pd->tx_queue.next = last->next;
617                 last->next = 0;
618         }
619         pd->last_sent_frame = &pd->tx_queue;
620         spin_unlock(&pd->tx_frame_lock);
621         while (first) {
622                 f = container_of(first, struct oz_tx_frame, link);
623                 first = first->next;
624                 oz_retire_frame(pd, f);
625         }
626 }
627 /*------------------------------------------------------------------------------
628  * Precondition: stream_lock must be held.
629  * Context: softirq
630  */
631 static struct oz_isoc_stream *pd_stream_find(struct oz_pd *pd, u8 ep_num)
632 {
633         struct list_head *e;
634         struct oz_isoc_stream *st;
635         list_for_each(e, &pd->stream_list) {
636                 st = container_of(e, struct oz_isoc_stream, link);
637                 if (st->ep_num == ep_num)
638                         return st;
639         }
640         return 0;
641 }
642 /*------------------------------------------------------------------------------
643  * Context: softirq
644  */
645 int oz_isoc_stream_create(struct oz_pd *pd, u8 ep_num)
646 {
647         struct oz_isoc_stream *st =
648                 kzalloc(sizeof(struct oz_isoc_stream), GFP_ATOMIC);
649         if (!st)
650                 return -ENOMEM;
651         st->ep_num = ep_num;
652         spin_lock_bh(&pd->stream_lock);
653         if (!pd_stream_find(pd, ep_num)) {
654                 list_add(&st->link, &pd->stream_list);
655                 st = 0;
656         }
657         spin_unlock_bh(&pd->stream_lock);
658         if (st)
659                 kfree(st);
660         return 0;
661 }
662 /*------------------------------------------------------------------------------
663  * Context: softirq or process
664  */
665 static void oz_isoc_stream_free(struct oz_isoc_stream *st)
666 {
667         if (st->skb)
668                 kfree_skb(st->skb);
669         kfree(st);
670 }
671 /*------------------------------------------------------------------------------
672  * Context: softirq
673  */
674 int oz_isoc_stream_delete(struct oz_pd *pd, u8 ep_num)
675 {
676         struct oz_isoc_stream *st;
677         spin_lock_bh(&pd->stream_lock);
678         st = pd_stream_find(pd, ep_num);
679         if (st)
680                 list_del(&st->link);
681         spin_unlock_bh(&pd->stream_lock);
682         if (st)
683                 oz_isoc_stream_free(st);
684         return 0;
685 }
686 /*------------------------------------------------------------------------------
687  * Context: any
688  */
689 static void oz_isoc_destructor(struct sk_buff *skb)
690 {
691         atomic_dec(&g_submitted_isoc);
692         oz_event_log(OZ_EVT_TX_ISOC_DONE, atomic_read(&g_submitted_isoc),
693                 0, skb, 0);
694 }
695 /*------------------------------------------------------------------------------
696  * Context: softirq
697  */
698 int oz_send_isoc_unit(struct oz_pd *pd, u8 ep_num, u8 *data, int len)
699 {
700         struct net_device *dev = pd->net_dev;
701         struct oz_isoc_stream *st;
702         u8 nb_units = 0;
703         struct sk_buff *skb = 0;
704         struct oz_hdr *oz_hdr = 0;
705         int size = 0;
706         spin_lock_bh(&pd->stream_lock);
707         st = pd_stream_find(pd, ep_num);
708         if (st) {
709                 skb = st->skb;
710                 st->skb = 0;
711                 nb_units = st->nb_units;
712                 st->nb_units = 0;
713                 oz_hdr = st->oz_hdr;
714                 size = st->size;
715         }
716         spin_unlock_bh(&pd->stream_lock);
717         if (!st)
718                 return 0;
719         if (!skb) {
720                 /* Allocate enough space for max size frame. */
721                 skb = alloc_skb(pd->max_tx_size + OZ_ALLOCATED_SPACE(dev),
722                                 GFP_ATOMIC);
723                 if (skb == 0)
724                         return 0;
725                 /* Reserve the head room for lower layers. */
726                 skb_reserve(skb, LL_RESERVED_SPACE(dev));
727                 skb_reset_network_header(skb);
728                 skb->dev = dev;
729                 skb->protocol = htons(OZ_ETHERTYPE);
730                 size = sizeof(struct oz_hdr) + sizeof(struct oz_isoc_large);
731                 oz_hdr = (struct oz_hdr *)skb_put(skb, size);
732         }
733         memcpy(skb_put(skb, len), data, len);
734         size += len;
735         if (++nb_units < pd->ms_per_isoc) {
736                 spin_lock_bh(&pd->stream_lock);
737                 st->skb = skb;
738                 st->nb_units = nb_units;
739                 st->oz_hdr = oz_hdr;
740                 st->size = size;
741                 spin_unlock_bh(&pd->stream_lock);
742         } else {
743                 struct oz_hdr oz;
744                 struct oz_isoc_large iso;
745                 spin_lock_bh(&pd->stream_lock);
746                 iso.frame_number = st->frame_num;
747                 st->frame_num += nb_units;
748                 spin_unlock_bh(&pd->stream_lock);
749                 oz.control =
750                         (OZ_PROTOCOL_VERSION<<OZ_VERSION_SHIFT) | OZ_F_ISOC;
751                 oz.last_pkt_num = pd->trigger_pkt_num & OZ_LAST_PN_MASK;
752                 oz.pkt_num = 0;
753                 iso.endpoint = ep_num;
754                 iso.format = OZ_DATA_F_ISOC_LARGE;
755                 iso.ms_data = nb_units;
756                 memcpy(oz_hdr, &oz, sizeof(oz));
757                 memcpy(oz_hdr+1, &iso, sizeof(iso));
758                 if (dev_hard_header(skb, dev, OZ_ETHERTYPE, pd->mac_addr,
759                                 dev->dev_addr, skb->len) < 0) {
760                         kfree_skb(skb);
761                         return -1;
762                 }
763                 if (atomic_read(&g_submitted_isoc) < OZ_MAX_SUBMITTED_ISOC) {
764                         skb->destructor = oz_isoc_destructor;
765                         atomic_inc(&g_submitted_isoc);
766                         oz_event_log(OZ_EVT_TX_ISOC, nb_units, iso.frame_number,
767                                 skb, atomic_read(&g_submitted_isoc));
768                         if (dev_queue_xmit(skb) < 0)
769                                 return -1;
770                 } else {
771                         oz_event_log(OZ_EVT_TX_ISOC_DROP, 0, 0, 0, 0);
772                         kfree_skb(skb);
773                 }
774         }
775         return 0;
776 }
777 /*------------------------------------------------------------------------------
778  * Context: process
779  */
780 void oz_apps_init(void)
781 {
782         int i;
783         for (i = 0; i < OZ_APPID_MAX; i++)
784                 if (g_app_if[i].init)
785                         g_app_if[i].init();
786 }
787 /*------------------------------------------------------------------------------
788  * Context: process
789  */
790 void oz_apps_term(void)
791 {
792         int i;
793         /* Terminate all the apps. */
794         for (i = 0; i < OZ_APPID_MAX; i++)
795                 if (g_app_if[i].term)
796                         g_app_if[i].term();
797 }
798 /*------------------------------------------------------------------------------
799  * Context: softirq-serialized
800  */
801 void oz_handle_app_elt(struct oz_pd *pd, u8 app_id, struct oz_elt *elt)
802 {
803         struct oz_app_if *ai;
804         if (app_id == 0 || app_id > OZ_APPID_MAX)
805                 return;
806         ai = &g_app_if[app_id-1];
807         ai->rx(pd, elt);
808 }
809 /*------------------------------------------------------------------------------
810  * Context: softirq or process
811  */
812 void oz_pd_indicate_farewells(struct oz_pd *pd)
813 {
814         struct oz_farewell *f;
815         struct oz_app_if *ai = &g_app_if[OZ_APPID_USB-1];
816         while (1) {
817                 oz_polling_lock_bh();
818                 if (list_empty(&pd->farewell_list)) {
819                         oz_polling_unlock_bh();
820                         break;
821                 }
822                 f = list_first_entry(&pd->farewell_list,
823                                 struct oz_farewell, link);
824                 list_del(&f->link);
825                 oz_polling_unlock_bh();
826                 if (ai->farewell)
827                         ai->farewell(pd, f->ep_num, f->report, f->len);
828                 kfree(f);
829         }
830 }