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 }