st_core.c revision bfb88d6c91a2cf507ff7763ebec94d72b4c98b07
1/* 2 * Shared Transport Line discipline driver Core 3 * This hooks up ST KIM driver and ST LL driver 4 * Copyright (C) 2009-2010 Texas Instruments 5 * Author: Pavan Savoy <pavan_savoy@ti.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 */ 21 22#define pr_fmt(fmt) "(stc): " fmt 23#include <linux/module.h> 24#include <linux/kernel.h> 25#include <linux/init.h> 26#include <linux/tty.h> 27 28#include <linux/seq_file.h> 29#include <linux/skbuff.h> 30 31#include <linux/ti_wilink_st.h> 32 33/* function pointer pointing to either, 34 * st_kim_recv during registration to receive fw download responses 35 * st_int_recv after registration to receive proto stack responses 36 */ 37void (*st_recv) (void*, const unsigned char*, long); 38 39/********************************************************************/ 40static void add_channel_to_table(struct st_data_s *st_gdata, 41 struct st_proto_s *new_proto) 42{ 43 pr_info("%s: id %d\n", __func__, new_proto->chnl_id); 44 /* list now has the channel id as index itself */ 45 st_gdata->list[new_proto->chnl_id] = new_proto; 46 st_gdata->is_registered[new_proto->chnl_id] = true; 47} 48 49static void remove_channel_from_table(struct st_data_s *st_gdata, 50 struct st_proto_s *proto) 51{ 52 pr_info("%s: id %d\n", __func__, proto->chnl_id); 53/* st_gdata->list[proto->chnl_id] = NULL; */ 54 st_gdata->is_registered[proto->chnl_id] = false; 55} 56 57/* 58 * called from KIM during firmware download. 59 * 60 * This is a wrapper function to tty->ops->write_room. 61 * It returns number of free space available in 62 * uart tx buffer. 63 */ 64int st_get_uart_wr_room(struct st_data_s *st_gdata) 65{ 66 struct tty_struct *tty; 67 if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) { 68 pr_err("tty unavailable to perform write"); 69 return -1; 70 } 71 tty = st_gdata->tty; 72 return tty->ops->write_room(tty); 73} 74 75/* can be called in from 76 * -- KIM (during fw download) 77 * -- ST Core (during st_write) 78 * 79 * This is the internal write function - a wrapper 80 * to tty->ops->write 81 */ 82int st_int_write(struct st_data_s *st_gdata, 83 const unsigned char *data, int count) 84{ 85 struct tty_struct *tty; 86 if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) { 87 pr_err("tty unavailable to perform write"); 88 return -EINVAL; 89 } 90 tty = st_gdata->tty; 91#ifdef VERBOSE 92 print_hex_dump(KERN_DEBUG, "<out<", DUMP_PREFIX_NONE, 93 16, 1, data, count, 0); 94#endif 95 return tty->ops->write(tty, data, count); 96 97} 98 99/* 100 * push the skb received to relevant 101 * protocol stacks 102 */ 103void st_send_frame(unsigned char chnl_id, struct st_data_s *st_gdata) 104{ 105 pr_debug(" %s(prot:%d) ", __func__, chnl_id); 106 107 if (unlikely 108 (st_gdata == NULL || st_gdata->rx_skb == NULL 109 || st_gdata->is_registered[chnl_id] == false)) { 110 pr_err("chnl_id %d not registered, no data to send?", 111 chnl_id); 112 kfree_skb(st_gdata->rx_skb); 113 return; 114 } 115 /* this cannot fail 116 * this shouldn't take long 117 * - should be just skb_queue_tail for the 118 * protocol stack driver 119 */ 120 if (likely(st_gdata->list[chnl_id]->recv != NULL)) { 121 if (unlikely 122 (st_gdata->list[chnl_id]->recv 123 (st_gdata->list[chnl_id]->priv_data, st_gdata->rx_skb) 124 != 0)) { 125 pr_err(" proto stack %d's ->recv failed", chnl_id); 126 kfree_skb(st_gdata->rx_skb); 127 return; 128 } 129 } else { 130 pr_err(" proto stack %d's ->recv null", chnl_id); 131 kfree_skb(st_gdata->rx_skb); 132 } 133 return; 134} 135 136/** 137 * st_reg_complete - 138 * to call registration complete callbacks 139 * of all protocol stack drivers 140 * This function is being called with spin lock held, protocol drivers are 141 * only expected to complete their waits and do nothing more than that. 142 */ 143void st_reg_complete(struct st_data_s *st_gdata, char err) 144{ 145 unsigned char i = 0; 146 pr_info(" %s ", __func__); 147 for (i = 0; i < ST_MAX_CHANNELS; i++) { 148 if (likely(st_gdata != NULL && 149 st_gdata->is_registered[i] == true && 150 st_gdata->list[i]->reg_complete_cb != NULL)) { 151 st_gdata->list[i]->reg_complete_cb 152 (st_gdata->list[i]->priv_data, err); 153 pr_info("protocol %d's cb sent %d\n", i, err); 154 if (err) { /* cleanup registered protocol */ 155 st_gdata->protos_registered--; 156 st_gdata->is_registered[i] = false; 157 } 158 } 159 } 160} 161 162static inline int st_check_data_len(struct st_data_s *st_gdata, 163 unsigned char chnl_id, int len) 164{ 165 int room = skb_tailroom(st_gdata->rx_skb); 166 167 pr_debug("len %d room %d", len, room); 168 169 if (!len) { 170 /* Received packet has only packet header and 171 * has zero length payload. So, ask ST CORE to 172 * forward the packet to protocol driver (BT/FM/GPS) 173 */ 174 st_send_frame(chnl_id, st_gdata); 175 176 } else if (len > room) { 177 /* Received packet's payload length is larger. 178 * We can't accommodate it in created skb. 179 */ 180 pr_err("Data length is too large len %d room %d", len, 181 room); 182 kfree_skb(st_gdata->rx_skb); 183 } else { 184 /* Packet header has non-zero payload length and 185 * we have enough space in created skb. Lets read 186 * payload data */ 187 st_gdata->rx_state = ST_W4_DATA; 188 st_gdata->rx_count = len; 189 return len; 190 } 191 192 /* Change ST state to continue to process next 193 * packet */ 194 st_gdata->rx_state = ST_W4_PACKET_TYPE; 195 st_gdata->rx_skb = NULL; 196 st_gdata->rx_count = 0; 197 st_gdata->rx_chnl = 0; 198 199 return 0; 200} 201 202/** 203 * st_wakeup_ack - internal function for action when wake-up ack 204 * received 205 */ 206static inline void st_wakeup_ack(struct st_data_s *st_gdata, 207 unsigned char cmd) 208{ 209 struct sk_buff *waiting_skb; 210 unsigned long flags = 0; 211 212 spin_lock_irqsave(&st_gdata->lock, flags); 213 /* de-Q from waitQ and Q in txQ now that the 214 * chip is awake 215 */ 216 while ((waiting_skb = skb_dequeue(&st_gdata->tx_waitq))) 217 skb_queue_tail(&st_gdata->txq, waiting_skb); 218 219 /* state forwarded to ST LL */ 220 st_ll_sleep_state(st_gdata, (unsigned long)cmd); 221 spin_unlock_irqrestore(&st_gdata->lock, flags); 222 223 /* wake up to send the recently copied skbs from waitQ */ 224 st_tx_wakeup(st_gdata); 225} 226 227/** 228 * st_int_recv - ST's internal receive function. 229 * Decodes received RAW data and forwards to corresponding 230 * client drivers (Bluetooth,FM,GPS..etc). 231 * This can receive various types of packets, 232 * HCI-Events, ACL, SCO, 4 types of HCI-LL PM packets 233 * CH-8 packets from FM, CH-9 packets from GPS cores. 234 */ 235void st_int_recv(void *disc_data, 236 const unsigned char *data, long count) 237{ 238 char *ptr; 239 struct st_proto_s *proto; 240 unsigned short payload_len = 0; 241 int len = 0, type = 0; 242 unsigned char *plen; 243 struct st_data_s *st_gdata = (struct st_data_s *)disc_data; 244 unsigned long flags; 245 246 ptr = (char *)data; 247 /* tty_receive sent null ? */ 248 if (unlikely(ptr == NULL) || (st_gdata == NULL)) { 249 pr_err(" received null from TTY "); 250 return; 251 } 252 253 pr_debug("count %ld rx_state %ld" 254 "rx_count %ld", count, st_gdata->rx_state, 255 st_gdata->rx_count); 256 257 spin_lock_irqsave(&st_gdata->lock, flags); 258 /* Decode received bytes here */ 259 while (count) { 260 if (st_gdata->rx_count) { 261 len = min_t(unsigned int, st_gdata->rx_count, count); 262 memcpy(skb_put(st_gdata->rx_skb, len), ptr, len); 263 st_gdata->rx_count -= len; 264 count -= len; 265 ptr += len; 266 267 if (st_gdata->rx_count) 268 continue; 269 270 /* Check ST RX state machine , where are we? */ 271 switch (st_gdata->rx_state) { 272 /* Waiting for complete packet ? */ 273 case ST_W4_DATA: 274 pr_debug("Complete pkt received"); 275 /* Ask ST CORE to forward 276 * the packet to protocol driver */ 277 st_send_frame(st_gdata->rx_chnl, st_gdata); 278 279 st_gdata->rx_state = ST_W4_PACKET_TYPE; 280 st_gdata->rx_skb = NULL; 281 continue; 282 /* parse the header to know details */ 283 case ST_W4_HEADER: 284 proto = st_gdata->list[st_gdata->rx_chnl]; 285 plen = 286 &st_gdata->rx_skb->data 287 [proto->offset_len_in_hdr]; 288 pr_debug("plen pointing to %x\n", *plen); 289 if (proto->len_size == 1)/* 1 byte len field */ 290 payload_len = *(unsigned char *)plen; 291 else if (proto->len_size == 2) 292 payload_len = 293 __le16_to_cpu(*(unsigned short *)plen); 294 else 295 pr_info("%s: invalid length " 296 "for id %d\n", 297 __func__, proto->chnl_id); 298 st_check_data_len(st_gdata, proto->chnl_id, 299 payload_len); 300 pr_debug("off %d, pay len %d\n", 301 proto->offset_len_in_hdr, payload_len); 302 continue; 303 } /* end of switch rx_state */ 304 } 305 306 /* end of if rx_count */ 307 /* Check first byte of packet and identify module 308 * owner (BT/FM/GPS) */ 309 switch (*ptr) { 310 case LL_SLEEP_IND: 311 case LL_SLEEP_ACK: 312 case LL_WAKE_UP_IND: 313 pr_debug("PM packet"); 314 /* this takes appropriate action based on 315 * sleep state received -- 316 */ 317 st_ll_sleep_state(st_gdata, *ptr); 318 /* if WAKEUP_IND collides copy from waitq to txq 319 * and assume chip awake 320 */ 321 spin_unlock_irqrestore(&st_gdata->lock, flags); 322 if (st_ll_getstate(st_gdata) == ST_LL_AWAKE) 323 st_wakeup_ack(st_gdata, LL_WAKE_UP_ACK); 324 spin_lock_irqsave(&st_gdata->lock, flags); 325 326 ptr++; 327 count--; 328 continue; 329 case LL_WAKE_UP_ACK: 330 pr_debug("PM packet"); 331 332 spin_unlock_irqrestore(&st_gdata->lock, flags); 333 /* wake up ack received */ 334 st_wakeup_ack(st_gdata, *ptr); 335 spin_lock_irqsave(&st_gdata->lock, flags); 336 337 ptr++; 338 count--; 339 continue; 340 /* Unknow packet? */ 341 default: 342 type = *ptr; 343 if (st_gdata->list[type] == NULL) { 344 pr_err("chip/interface misbehavior dropping" 345 " frame starting with 0x%02x", type); 346 goto done; 347 348 } 349 st_gdata->rx_skb = alloc_skb( 350 st_gdata->list[type]->max_frame_size, 351 GFP_ATOMIC); 352 skb_reserve(st_gdata->rx_skb, 353 st_gdata->list[type]->reserve); 354 /* next 2 required for BT only */ 355 st_gdata->rx_skb->cb[0] = type; /*pkt_type*/ 356 st_gdata->rx_skb->cb[1] = 0; /*incoming*/ 357 st_gdata->rx_chnl = *ptr; 358 st_gdata->rx_state = ST_W4_HEADER; 359 st_gdata->rx_count = st_gdata->list[type]->hdr_len; 360 pr_debug("rx_count %ld\n", st_gdata->rx_count); 361 }; 362 ptr++; 363 count--; 364 } 365done: 366 spin_unlock_irqrestore(&st_gdata->lock, flags); 367 pr_debug("done %s", __func__); 368 return; 369} 370 371/** 372 * st_int_dequeue - internal de-Q function. 373 * If the previous data set was not written 374 * completely, return that skb which has the pending data. 375 * In normal cases, return top of txq. 376 */ 377struct sk_buff *st_int_dequeue(struct st_data_s *st_gdata) 378{ 379 struct sk_buff *returning_skb; 380 381 pr_debug("%s", __func__); 382 if (st_gdata->tx_skb != NULL) { 383 returning_skb = st_gdata->tx_skb; 384 st_gdata->tx_skb = NULL; 385 return returning_skb; 386 } 387 return skb_dequeue(&st_gdata->txq); 388} 389 390/** 391 * st_int_enqueue - internal Q-ing function. 392 * Will either Q the skb to txq or the tx_waitq 393 * depending on the ST LL state. 394 * If the chip is asleep, then Q it onto waitq and 395 * wakeup the chip. 396 * txq and waitq needs protection since the other contexts 397 * may be sending data, waking up chip. 398 */ 399void st_int_enqueue(struct st_data_s *st_gdata, struct sk_buff *skb) 400{ 401 unsigned long flags = 0; 402 403 pr_debug("%s", __func__); 404 spin_lock_irqsave(&st_gdata->lock, flags); 405 406 switch (st_ll_getstate(st_gdata)) { 407 case ST_LL_AWAKE: 408 pr_debug("ST LL is AWAKE, sending normally"); 409 skb_queue_tail(&st_gdata->txq, skb); 410 break; 411 case ST_LL_ASLEEP_TO_AWAKE: 412 skb_queue_tail(&st_gdata->tx_waitq, skb); 413 break; 414 case ST_LL_AWAKE_TO_ASLEEP: 415 pr_err("ST LL is illegal state(%ld)," 416 "purging received skb.", st_ll_getstate(st_gdata)); 417 kfree_skb(skb); 418 break; 419 case ST_LL_ASLEEP: 420 skb_queue_tail(&st_gdata->tx_waitq, skb); 421 st_ll_wakeup(st_gdata); 422 break; 423 default: 424 pr_err("ST LL is illegal state(%ld)," 425 "purging received skb.", st_ll_getstate(st_gdata)); 426 kfree_skb(skb); 427 break; 428 } 429 430 spin_unlock_irqrestore(&st_gdata->lock, flags); 431 pr_debug("done %s", __func__); 432 return; 433} 434 435/* 436 * internal wakeup function 437 * called from either 438 * - TTY layer when write's finished 439 * - st_write (in context of the protocol stack) 440 */ 441void st_tx_wakeup(struct st_data_s *st_data) 442{ 443 struct sk_buff *skb; 444 unsigned long flags; /* for irq save flags */ 445 pr_debug("%s", __func__); 446 /* check for sending & set flag sending here */ 447 if (test_and_set_bit(ST_TX_SENDING, &st_data->tx_state)) { 448 pr_debug("ST already sending"); 449 /* keep sending */ 450 set_bit(ST_TX_WAKEUP, &st_data->tx_state); 451 return; 452 /* TX_WAKEUP will be checked in another 453 * context 454 */ 455 } 456 do { /* come back if st_tx_wakeup is set */ 457 /* woke-up to write */ 458 clear_bit(ST_TX_WAKEUP, &st_data->tx_state); 459 while ((skb = st_int_dequeue(st_data))) { 460 int len; 461 spin_lock_irqsave(&st_data->lock, flags); 462 /* enable wake-up from TTY */ 463 set_bit(TTY_DO_WRITE_WAKEUP, &st_data->tty->flags); 464 len = st_int_write(st_data, skb->data, skb->len); 465 skb_pull(skb, len); 466 /* if skb->len = len as expected, skb->len=0 */ 467 if (skb->len) { 468 /* would be the next skb to be sent */ 469 st_data->tx_skb = skb; 470 spin_unlock_irqrestore(&st_data->lock, flags); 471 break; 472 } 473 kfree_skb(skb); 474 spin_unlock_irqrestore(&st_data->lock, flags); 475 } 476 /* if wake-up is set in another context- restart sending */ 477 } while (test_bit(ST_TX_WAKEUP, &st_data->tx_state)); 478 479 /* clear flag sending */ 480 clear_bit(ST_TX_SENDING, &st_data->tx_state); 481} 482 483/********************************************************************/ 484/* functions called from ST KIM 485*/ 486void kim_st_list_protocols(struct st_data_s *st_gdata, void *buf) 487{ 488 seq_printf(buf, "[%d]\nBT=%c\nFM=%c\nGPS=%c\n", 489 st_gdata->protos_registered, 490 st_gdata->is_registered[0x04] == true ? 'R' : 'U', 491 st_gdata->is_registered[0x08] == true ? 'R' : 'U', 492 st_gdata->is_registered[0x09] == true ? 'R' : 'U'); 493} 494 495/********************************************************************/ 496/* 497 * functions called from protocol stack drivers 498 * to be EXPORT-ed 499 */ 500long st_register(struct st_proto_s *new_proto) 501{ 502 struct st_data_s *st_gdata; 503 long err = 0; 504 unsigned long flags = 0; 505 506 st_kim_ref(&st_gdata, 0); 507 pr_info("%s(%d) ", __func__, new_proto->chnl_id); 508 if (st_gdata == NULL || new_proto == NULL || new_proto->recv == NULL 509 || new_proto->reg_complete_cb == NULL) { 510 pr_err("gdata/new_proto/recv or reg_complete_cb not ready"); 511 return -EINVAL; 512 } 513 514 if (new_proto->chnl_id >= ST_MAX_CHANNELS) { 515 pr_err("chnl_id %d not supported", new_proto->chnl_id); 516 return -EPROTONOSUPPORT; 517 } 518 519 if (st_gdata->is_registered[new_proto->chnl_id] == true) { 520 pr_err("chnl_id %d already registered", new_proto->chnl_id); 521 return -EALREADY; 522 } 523 524 /* can be from process context only */ 525 spin_lock_irqsave(&st_gdata->lock, flags); 526 527 if (test_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state)) { 528 pr_info(" ST_REG_IN_PROGRESS:%d ", new_proto->chnl_id); 529 /* fw download in progress */ 530 531 add_channel_to_table(st_gdata, new_proto); 532 st_gdata->protos_registered++; 533 new_proto->write = st_write; 534 535 set_bit(ST_REG_PENDING, &st_gdata->st_state); 536 spin_unlock_irqrestore(&st_gdata->lock, flags); 537 return -EINPROGRESS; 538 } else if (st_gdata->protos_registered == ST_EMPTY) { 539 pr_info(" chnl_id list empty :%d ", new_proto->chnl_id); 540 set_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); 541 st_recv = st_kim_recv; 542 543 /* enable the ST LL - to set default chip state */ 544 st_ll_enable(st_gdata); 545 546 /* release lock previously held - re-locked below */ 547 spin_unlock_irqrestore(&st_gdata->lock, flags); 548 549 /* this may take a while to complete 550 * since it involves BT fw download 551 */ 552 err = st_kim_start(st_gdata->kim_data); 553 if (err != 0) { 554 clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); 555 if ((st_gdata->protos_registered != ST_EMPTY) && 556 (test_bit(ST_REG_PENDING, &st_gdata->st_state))) { 557 pr_err(" KIM failure complete callback "); 558 st_reg_complete(st_gdata, err); 559 clear_bit(ST_REG_PENDING, &st_gdata->st_state); 560 } 561 return -EINVAL; 562 } 563 564 spin_lock_irqsave(&st_gdata->lock, flags); 565 566 clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); 567 st_recv = st_int_recv; 568 569 /* this is where all pending registration 570 * are signalled to be complete by calling callback functions 571 */ 572 if ((st_gdata->protos_registered != ST_EMPTY) && 573 (test_bit(ST_REG_PENDING, &st_gdata->st_state))) { 574 pr_debug(" call reg complete callback "); 575 st_reg_complete(st_gdata, 0); 576 } 577 clear_bit(ST_REG_PENDING, &st_gdata->st_state); 578 579 /* check for already registered once more, 580 * since the above check is old 581 */ 582 if (st_gdata->is_registered[new_proto->chnl_id] == true) { 583 pr_err(" proto %d already registered ", 584 new_proto->chnl_id); 585 spin_unlock_irqrestore(&st_gdata->lock, flags); 586 return -EALREADY; 587 } 588 589 add_channel_to_table(st_gdata, new_proto); 590 st_gdata->protos_registered++; 591 new_proto->write = st_write; 592 spin_unlock_irqrestore(&st_gdata->lock, flags); 593 return err; 594 } 595 /* if fw is already downloaded & new stack registers protocol */ 596 else { 597 add_channel_to_table(st_gdata, new_proto); 598 st_gdata->protos_registered++; 599 new_proto->write = st_write; 600 601 /* lock already held before entering else */ 602 spin_unlock_irqrestore(&st_gdata->lock, flags); 603 return err; 604 } 605 pr_debug("done %s(%d) ", __func__, new_proto->chnl_id); 606} 607EXPORT_SYMBOL_GPL(st_register); 608 609/* to unregister a protocol - 610 * to be called from protocol stack driver 611 */ 612long st_unregister(struct st_proto_s *proto) 613{ 614 long err = 0; 615 unsigned long flags = 0; 616 struct st_data_s *st_gdata; 617 618 pr_debug("%s: %d ", __func__, proto->chnl_id); 619 620 st_kim_ref(&st_gdata, 0); 621 if (!st_gdata || proto->chnl_id >= ST_MAX_CHANNELS) { 622 pr_err(" chnl_id %d not supported", proto->chnl_id); 623 return -EPROTONOSUPPORT; 624 } 625 626 spin_lock_irqsave(&st_gdata->lock, flags); 627 628 if (st_gdata->is_registered[proto->chnl_id] == false) { 629 pr_err(" chnl_id %d not registered", proto->chnl_id); 630 spin_unlock_irqrestore(&st_gdata->lock, flags); 631 return -EPROTONOSUPPORT; 632 } 633 634 st_gdata->protos_registered--; 635 remove_channel_from_table(st_gdata, proto); 636 spin_unlock_irqrestore(&st_gdata->lock, flags); 637 638 /* paranoid check */ 639 if (st_gdata->protos_registered < ST_EMPTY) 640 st_gdata->protos_registered = ST_EMPTY; 641 642 if ((st_gdata->protos_registered == ST_EMPTY) && 643 (!test_bit(ST_REG_PENDING, &st_gdata->st_state))) { 644 pr_info(" all chnl_ids unregistered "); 645 646 /* stop traffic on tty */ 647 if (st_gdata->tty) { 648 tty_ldisc_flush(st_gdata->tty); 649 stop_tty(st_gdata->tty); 650 } 651 652 /* all chnl_ids now unregistered */ 653 st_kim_stop(st_gdata->kim_data); 654 /* disable ST LL */ 655 st_ll_disable(st_gdata); 656 } 657 return err; 658} 659 660/* 661 * called in protocol stack drivers 662 * via the write function pointer 663 */ 664long st_write(struct sk_buff *skb) 665{ 666 struct st_data_s *st_gdata; 667 long len; 668 669 st_kim_ref(&st_gdata, 0); 670 if (unlikely(skb == NULL || st_gdata == NULL 671 || st_gdata->tty == NULL)) { 672 pr_err("data/tty unavailable to perform write"); 673 return -EINVAL; 674 } 675 676 pr_debug("%d to be written", skb->len); 677 len = skb->len; 678 679 /* st_ll to decide where to enqueue the skb */ 680 st_int_enqueue(st_gdata, skb); 681 /* wake up */ 682 st_tx_wakeup(st_gdata); 683 684 /* return number of bytes written */ 685 return len; 686} 687 688/* for protocols making use of shared transport */ 689EXPORT_SYMBOL_GPL(st_unregister); 690 691/********************************************************************/ 692/* 693 * functions called from TTY layer 694 */ 695static int st_tty_open(struct tty_struct *tty) 696{ 697 int err = 0; 698 struct st_data_s *st_gdata; 699 pr_info("%s ", __func__); 700 701 st_kim_ref(&st_gdata, 0); 702 st_gdata->tty = tty; 703 tty->disc_data = st_gdata; 704 705 /* don't do an wakeup for now */ 706 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 707 708 /* mem already allocated 709 */ 710 tty->receive_room = 65536; 711 /* Flush any pending characters in the driver and discipline. */ 712 tty_ldisc_flush(tty); 713 tty_driver_flush_buffer(tty); 714 /* 715 * signal to UIM via KIM that - 716 * installation of N_TI_WL ldisc is complete 717 */ 718 st_kim_complete(st_gdata->kim_data); 719 pr_debug("done %s", __func__); 720 return err; 721} 722 723static void st_tty_close(struct tty_struct *tty) 724{ 725 unsigned char i = ST_MAX_CHANNELS; 726 unsigned long flags = 0; 727 struct st_data_s *st_gdata = tty->disc_data; 728 729 pr_info("%s ", __func__); 730 731 /* TODO: 732 * if a protocol has been registered & line discipline 733 * un-installed for some reason - what should be done ? 734 */ 735 spin_lock_irqsave(&st_gdata->lock, flags); 736 for (i = ST_BT; i < ST_MAX_CHANNELS; i++) { 737 if (st_gdata->is_registered[i] == true) 738 pr_err("%d not un-registered", i); 739 st_gdata->list[i] = NULL; 740 st_gdata->is_registered[i] = false; 741 } 742 st_gdata->protos_registered = 0; 743 spin_unlock_irqrestore(&st_gdata->lock, flags); 744 /* 745 * signal to UIM via KIM that - 746 * N_TI_WL ldisc is un-installed 747 */ 748 st_kim_complete(st_gdata->kim_data); 749 st_gdata->tty = NULL; 750 /* Flush any pending characters in the driver and discipline. */ 751 tty_ldisc_flush(tty); 752 tty_driver_flush_buffer(tty); 753 754 spin_lock_irqsave(&st_gdata->lock, flags); 755 /* empty out txq and tx_waitq */ 756 skb_queue_purge(&st_gdata->txq); 757 skb_queue_purge(&st_gdata->tx_waitq); 758 /* reset the TTY Rx states of ST */ 759 st_gdata->rx_count = 0; 760 st_gdata->rx_state = ST_W4_PACKET_TYPE; 761 kfree_skb(st_gdata->rx_skb); 762 st_gdata->rx_skb = NULL; 763 spin_unlock_irqrestore(&st_gdata->lock, flags); 764 765 pr_debug("%s: done ", __func__); 766} 767 768static void st_tty_receive(struct tty_struct *tty, const unsigned char *data, 769 char *tty_flags, int count) 770{ 771#ifdef VERBOSE 772 print_hex_dump(KERN_DEBUG, ">in>", DUMP_PREFIX_NONE, 773 16, 1, data, count, 0); 774#endif 775 776 /* 777 * if fw download is in progress then route incoming data 778 * to KIM for validation 779 */ 780 st_recv(tty->disc_data, data, count); 781 pr_debug("done %s", __func__); 782} 783 784/* wake-up function called in from the TTY layer 785 * inside the internal wakeup function will be called 786 */ 787static void st_tty_wakeup(struct tty_struct *tty) 788{ 789 struct st_data_s *st_gdata = tty->disc_data; 790 pr_debug("%s ", __func__); 791 /* don't do an wakeup for now */ 792 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 793 794 /* call our internal wakeup */ 795 st_tx_wakeup((void *)st_gdata); 796} 797 798static void st_tty_flush_buffer(struct tty_struct *tty) 799{ 800 struct st_data_s *st_gdata = tty->disc_data; 801 pr_debug("%s ", __func__); 802 803 kfree_skb(st_gdata->tx_skb); 804 st_gdata->tx_skb = NULL; 805 806 tty->ops->flush_buffer(tty); 807 return; 808} 809 810static struct tty_ldisc_ops st_ldisc_ops = { 811 .magic = TTY_LDISC_MAGIC, 812 .name = "n_st", 813 .open = st_tty_open, 814 .close = st_tty_close, 815 .receive_buf = st_tty_receive, 816 .write_wakeup = st_tty_wakeup, 817 .flush_buffer = st_tty_flush_buffer, 818 .owner = THIS_MODULE 819}; 820 821/********************************************************************/ 822int st_core_init(struct st_data_s **core_data) 823{ 824 struct st_data_s *st_gdata; 825 long err; 826 827 err = tty_register_ldisc(N_TI_WL, &st_ldisc_ops); 828 if (err) { 829 pr_err("error registering %d line discipline %ld", 830 N_TI_WL, err); 831 return err; 832 } 833 pr_debug("registered n_shared line discipline"); 834 835 st_gdata = kzalloc(sizeof(struct st_data_s), GFP_KERNEL); 836 if (!st_gdata) { 837 pr_err("memory allocation failed"); 838 err = tty_unregister_ldisc(N_TI_WL); 839 if (err) 840 pr_err("unable to un-register ldisc %ld", err); 841 err = -ENOMEM; 842 return err; 843 } 844 845 /* Initialize ST TxQ and Tx waitQ queue head. All BT/FM/GPS module skb's 846 * will be pushed in this queue for actual transmission. 847 */ 848 skb_queue_head_init(&st_gdata->txq); 849 skb_queue_head_init(&st_gdata->tx_waitq); 850 851 /* Locking used in st_int_enqueue() to avoid multiple execution */ 852 spin_lock_init(&st_gdata->lock); 853 854 err = st_ll_init(st_gdata); 855 if (err) { 856 pr_err("error during st_ll initialization(%ld)", err); 857 kfree(st_gdata); 858 err = tty_unregister_ldisc(N_TI_WL); 859 if (err) 860 pr_err("unable to un-register ldisc"); 861 return err; 862 } 863 *core_data = st_gdata; 864 return 0; 865} 866 867void st_core_exit(struct st_data_s *st_gdata) 868{ 869 long err; 870 /* internal module cleanup */ 871 err = st_ll_deinit(st_gdata); 872 if (err) 873 pr_err("error during deinit of ST LL %ld", err); 874 875 if (st_gdata != NULL) { 876 /* Free ST Tx Qs and skbs */ 877 skb_queue_purge(&st_gdata->txq); 878 skb_queue_purge(&st_gdata->tx_waitq); 879 kfree_skb(st_gdata->rx_skb); 880 kfree_skb(st_gdata->tx_skb); 881 /* TTY ldisc cleanup */ 882 err = tty_unregister_ldisc(N_TI_WL); 883 if (err) 884 pr_err("unable to un-register ldisc %ld", err); 885 /* free the global data pointer */ 886 kfree(st_gdata); 887 } 888} 889 890 891