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/tty.h> 26 27#include <linux/seq_file.h> 28#include <linux/skbuff.h> 29 30#include <linux/ti_wilink_st.h> 31 32extern void st_kim_recv(void *, const unsigned char *, long); 33void st_int_recv(void *, const unsigned char *, long); 34/* function pointer pointing to either, 35 * st_kim_recv during registration to receive fw download responses 36 * st_int_recv after registration to receive proto stack responses 37 */ 38static void (*st_recv) (void *, const unsigned char *, long); 39 40/********************************************************************/ 41static void add_channel_to_table(struct st_data_s *st_gdata, 42 struct st_proto_s *new_proto) 43{ 44 pr_info("%s: id %d\n", __func__, new_proto->chnl_id); 45 /* list now has the channel id as index itself */ 46 st_gdata->list[new_proto->chnl_id] = new_proto; 47 st_gdata->is_registered[new_proto->chnl_id] = true; 48} 49 50static void remove_channel_from_table(struct st_data_s *st_gdata, 51 struct st_proto_s *proto) 52{ 53 pr_info("%s: id %d\n", __func__, proto->chnl_id); 54/* st_gdata->list[proto->chnl_id] = NULL; */ 55 st_gdata->is_registered[proto->chnl_id] = false; 56} 57 58/* 59 * called from KIM during firmware download. 60 * 61 * This is a wrapper function to tty->ops->write_room. 62 * It returns number of free space available in 63 * uart tx buffer. 64 */ 65int st_get_uart_wr_room(struct st_data_s *st_gdata) 66{ 67 struct tty_struct *tty; 68 if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) { 69 pr_err("tty unavailable to perform write"); 70 return -1; 71 } 72 tty = st_gdata->tty; 73 return tty->ops->write_room(tty); 74} 75 76/* can be called in from 77 * -- KIM (during fw download) 78 * -- ST Core (during st_write) 79 * 80 * This is the internal write function - a wrapper 81 * to tty->ops->write 82 */ 83int st_int_write(struct st_data_s *st_gdata, 84 const unsigned char *data, int count) 85{ 86 struct tty_struct *tty; 87 if (unlikely(st_gdata == NULL || st_gdata->tty == NULL)) { 88 pr_err("tty unavailable to perform write"); 89 return -EINVAL; 90 } 91 tty = st_gdata->tty; 92#ifdef VERBOSE 93 print_hex_dump(KERN_DEBUG, "<out<", DUMP_PREFIX_NONE, 94 16, 1, data, count, 0); 95#endif 96 return tty->ops->write(tty, data, count); 97 98} 99 100/* 101 * push the skb received to relevant 102 * protocol stacks 103 */ 104static void st_send_frame(unsigned char chnl_id, struct st_data_s *st_gdata) 105{ 106 pr_debug(" %s(prot:%d) ", __func__, chnl_id); 107 108 if (unlikely 109 (st_gdata == NULL || st_gdata->rx_skb == NULL 110 || st_gdata->is_registered[chnl_id] == false)) { 111 pr_err("chnl_id %d not registered, no data to send?", 112 chnl_id); 113 kfree_skb(st_gdata->rx_skb); 114 return; 115 } 116 /* this cannot fail 117 * this shouldn't take long 118 * - should be just skb_queue_tail for the 119 * protocol stack driver 120 */ 121 if (likely(st_gdata->list[chnl_id]->recv != NULL)) { 122 if (unlikely 123 (st_gdata->list[chnl_id]->recv 124 (st_gdata->list[chnl_id]->priv_data, st_gdata->rx_skb) 125 != 0)) { 126 pr_err(" proto stack %d's ->recv failed", chnl_id); 127 kfree_skb(st_gdata->rx_skb); 128 return; 129 } 130 } else { 131 pr_err(" proto stack %d's ->recv null", chnl_id); 132 kfree_skb(st_gdata->rx_skb); 133 } 134 return; 135} 136 137/** 138 * st_reg_complete - 139 * to call registration complete callbacks 140 * of all protocol stack drivers 141 * This function is being called with spin lock held, protocol drivers are 142 * only expected to complete their waits and do nothing more than that. 143 */ 144static void st_reg_complete(struct st_data_s *st_gdata, char err) 145{ 146 unsigned char i = 0; 147 pr_info(" %s ", __func__); 148 for (i = 0; i < ST_MAX_CHANNELS; i++) { 149 if (likely(st_gdata != NULL && 150 st_gdata->is_registered[i] == true && 151 st_gdata->list[i]->reg_complete_cb != NULL)) { 152 st_gdata->list[i]->reg_complete_cb 153 (st_gdata->list[i]->priv_data, err); 154 pr_info("protocol %d's cb sent %d\n", i, err); 155 if (err) { /* cleanup registered protocol */ 156 st_gdata->is_registered[i] = false; 157 if (st_gdata->protos_registered) 158 st_gdata->protos_registered--; 159 } 160 } 161 } 162} 163 164static inline int st_check_data_len(struct st_data_s *st_gdata, 165 unsigned char chnl_id, int len) 166{ 167 int room = skb_tailroom(st_gdata->rx_skb); 168 169 pr_debug("len %d room %d", len, room); 170 171 if (!len) { 172 /* Received packet has only packet header and 173 * has zero length payload. So, ask ST CORE to 174 * forward the packet to protocol driver (BT/FM/GPS) 175 */ 176 st_send_frame(chnl_id, st_gdata); 177 178 } else if (len > room) { 179 /* Received packet's payload length is larger. 180 * We can't accommodate it in created skb. 181 */ 182 pr_err("Data length is too large len %d room %d", len, 183 room); 184 kfree_skb(st_gdata->rx_skb); 185 } else { 186 /* Packet header has non-zero payload length and 187 * we have enough space in created skb. Lets read 188 * payload data */ 189 st_gdata->rx_state = ST_W4_DATA; 190 st_gdata->rx_count = len; 191 return len; 192 } 193 194 /* Change ST state to continue to process next 195 * packet */ 196 st_gdata->rx_state = ST_W4_PACKET_TYPE; 197 st_gdata->rx_skb = NULL; 198 st_gdata->rx_count = 0; 199 st_gdata->rx_chnl = 0; 200 201 return 0; 202} 203 204/** 205 * st_wakeup_ack - internal function for action when wake-up ack 206 * received 207 */ 208static inline void st_wakeup_ack(struct st_data_s *st_gdata, 209 unsigned char cmd) 210{ 211 struct sk_buff *waiting_skb; 212 unsigned long flags = 0; 213 214 spin_lock_irqsave(&st_gdata->lock, flags); 215 /* de-Q from waitQ and Q in txQ now that the 216 * chip is awake 217 */ 218 while ((waiting_skb = skb_dequeue(&st_gdata->tx_waitq))) 219 skb_queue_tail(&st_gdata->txq, waiting_skb); 220 221 /* state forwarded to ST LL */ 222 st_ll_sleep_state(st_gdata, (unsigned long)cmd); 223 spin_unlock_irqrestore(&st_gdata->lock, flags); 224 225 /* wake up to send the recently copied skbs from waitQ */ 226 st_tx_wakeup(st_gdata); 227} 228 229/** 230 * st_int_recv - ST's internal receive function. 231 * Decodes received RAW data and forwards to corresponding 232 * client drivers (Bluetooth,FM,GPS..etc). 233 * This can receive various types of packets, 234 * HCI-Events, ACL, SCO, 4 types of HCI-LL PM packets 235 * CH-8 packets from FM, CH-9 packets from GPS cores. 236 */ 237void st_int_recv(void *disc_data, 238 const unsigned char *data, long count) 239{ 240 char *ptr; 241 struct st_proto_s *proto; 242 unsigned short payload_len = 0; 243 int len = 0; 244 unsigned char type = 0; 245 unsigned char *plen; 246 struct st_data_s *st_gdata = (struct st_data_s *)disc_data; 247 unsigned long flags; 248 249 ptr = (char *)data; 250 /* tty_receive sent null ? */ 251 if (unlikely(ptr == NULL) || (st_gdata == NULL)) { 252 pr_err(" received null from TTY "); 253 return; 254 } 255 256 pr_debug("count %ld rx_state %ld" 257 "rx_count %ld", count, st_gdata->rx_state, 258 st_gdata->rx_count); 259 260 spin_lock_irqsave(&st_gdata->lock, flags); 261 /* Decode received bytes here */ 262 while (count) { 263 if (st_gdata->rx_count) { 264 len = min_t(unsigned int, st_gdata->rx_count, count); 265 memcpy(skb_put(st_gdata->rx_skb, len), ptr, len); 266 st_gdata->rx_count -= len; 267 count -= len; 268 ptr += len; 269 270 if (st_gdata->rx_count) 271 continue; 272 273 /* Check ST RX state machine , where are we? */ 274 switch (st_gdata->rx_state) { 275 /* Waiting for complete packet ? */ 276 case ST_W4_DATA: 277 pr_debug("Complete pkt received"); 278 /* Ask ST CORE to forward 279 * the packet to protocol driver */ 280 st_send_frame(st_gdata->rx_chnl, st_gdata); 281 282 st_gdata->rx_state = ST_W4_PACKET_TYPE; 283 st_gdata->rx_skb = NULL; 284 continue; 285 /* parse the header to know details */ 286 case ST_W4_HEADER: 287 proto = st_gdata->list[st_gdata->rx_chnl]; 288 plen = 289 &st_gdata->rx_skb->data 290 [proto->offset_len_in_hdr]; 291 pr_debug("plen pointing to %x\n", *plen); 292 if (proto->len_size == 1)/* 1 byte len field */ 293 payload_len = *(unsigned char *)plen; 294 else if (proto->len_size == 2) 295 payload_len = 296 __le16_to_cpu(*(unsigned short *)plen); 297 else 298 pr_info("%s: invalid length " 299 "for id %d\n", 300 __func__, proto->chnl_id); 301 st_check_data_len(st_gdata, proto->chnl_id, 302 payload_len); 303 pr_debug("off %d, pay len %d\n", 304 proto->offset_len_in_hdr, payload_len); 305 continue; 306 } /* end of switch rx_state */ 307 } 308 309 /* end of if rx_count */ 310 /* Check first byte of packet and identify module 311 * owner (BT/FM/GPS) */ 312 switch (*ptr) { 313 case LL_SLEEP_IND: 314 case LL_SLEEP_ACK: 315 case LL_WAKE_UP_IND: 316 pr_debug("PM packet"); 317 /* this takes appropriate action based on 318 * sleep state received -- 319 */ 320 st_ll_sleep_state(st_gdata, *ptr); 321 /* if WAKEUP_IND collides copy from waitq to txq 322 * and assume chip awake 323 */ 324 spin_unlock_irqrestore(&st_gdata->lock, flags); 325 if (st_ll_getstate(st_gdata) == ST_LL_AWAKE) 326 st_wakeup_ack(st_gdata, LL_WAKE_UP_ACK); 327 spin_lock_irqsave(&st_gdata->lock, flags); 328 329 ptr++; 330 count--; 331 continue; 332 case LL_WAKE_UP_ACK: 333 pr_debug("PM packet"); 334 335 spin_unlock_irqrestore(&st_gdata->lock, flags); 336 /* wake up ack received */ 337 st_wakeup_ack(st_gdata, *ptr); 338 spin_lock_irqsave(&st_gdata->lock, flags); 339 340 ptr++; 341 count--; 342 continue; 343 /* Unknow packet? */ 344 default: 345 type = *ptr; 346 347 /* Default case means non-HCILL packets, 348 * possibilities are packets for: 349 * (a) valid protocol - Supported Protocols within 350 * the ST_MAX_CHANNELS. 351 * (b) registered protocol - Checked by 352 * "st_gdata->list[type] == NULL)" are supported 353 * protocols only. 354 * Rules out any invalid protocol and 355 * unregistered protocols with channel ID < 16. 356 */ 357 358 if ((type >= ST_MAX_CHANNELS) || 359 (st_gdata->list[type] == NULL)) { 360 pr_err("chip/interface misbehavior: " 361 "dropping frame starting " 362 "with 0x%02x\n", type); 363 goto done; 364 } 365 366 st_gdata->rx_skb = alloc_skb( 367 st_gdata->list[type]->max_frame_size, 368 GFP_ATOMIC); 369 if (st_gdata->rx_skb == NULL) { 370 pr_err("out of memory: dropping\n"); 371 goto done; 372 } 373 374 skb_reserve(st_gdata->rx_skb, 375 st_gdata->list[type]->reserve); 376 /* next 2 required for BT only */ 377 st_gdata->rx_skb->cb[0] = type; /*pkt_type*/ 378 st_gdata->rx_skb->cb[1] = 0; /*incoming*/ 379 st_gdata->rx_chnl = *ptr; 380 st_gdata->rx_state = ST_W4_HEADER; 381 st_gdata->rx_count = st_gdata->list[type]->hdr_len; 382 pr_debug("rx_count %ld\n", st_gdata->rx_count); 383 }; 384 ptr++; 385 count--; 386 } 387done: 388 spin_unlock_irqrestore(&st_gdata->lock, flags); 389 pr_debug("done %s", __func__); 390 return; 391} 392 393/** 394 * st_int_dequeue - internal de-Q function. 395 * If the previous data set was not written 396 * completely, return that skb which has the pending data. 397 * In normal cases, return top of txq. 398 */ 399static struct sk_buff *st_int_dequeue(struct st_data_s *st_gdata) 400{ 401 struct sk_buff *returning_skb; 402 403 pr_debug("%s", __func__); 404 if (st_gdata->tx_skb != NULL) { 405 returning_skb = st_gdata->tx_skb; 406 st_gdata->tx_skb = NULL; 407 return returning_skb; 408 } 409 return skb_dequeue(&st_gdata->txq); 410} 411 412/** 413 * st_int_enqueue - internal Q-ing function. 414 * Will either Q the skb to txq or the tx_waitq 415 * depending on the ST LL state. 416 * If the chip is asleep, then Q it onto waitq and 417 * wakeup the chip. 418 * txq and waitq needs protection since the other contexts 419 * may be sending data, waking up chip. 420 */ 421static void st_int_enqueue(struct st_data_s *st_gdata, struct sk_buff *skb) 422{ 423 unsigned long flags = 0; 424 425 pr_debug("%s", __func__); 426 spin_lock_irqsave(&st_gdata->lock, flags); 427 428 switch (st_ll_getstate(st_gdata)) { 429 case ST_LL_AWAKE: 430 pr_debug("ST LL is AWAKE, sending normally"); 431 skb_queue_tail(&st_gdata->txq, skb); 432 break; 433 case ST_LL_ASLEEP_TO_AWAKE: 434 skb_queue_tail(&st_gdata->tx_waitq, skb); 435 break; 436 case ST_LL_AWAKE_TO_ASLEEP: 437 pr_err("ST LL is illegal state(%ld)," 438 "purging received skb.", st_ll_getstate(st_gdata)); 439 kfree_skb(skb); 440 break; 441 case ST_LL_ASLEEP: 442 skb_queue_tail(&st_gdata->tx_waitq, skb); 443 st_ll_wakeup(st_gdata); 444 break; 445 default: 446 pr_err("ST LL is illegal state(%ld)," 447 "purging received skb.", st_ll_getstate(st_gdata)); 448 kfree_skb(skb); 449 break; 450 } 451 452 spin_unlock_irqrestore(&st_gdata->lock, flags); 453 pr_debug("done %s", __func__); 454 return; 455} 456 457/* 458 * internal wakeup function 459 * called from either 460 * - TTY layer when write's finished 461 * - st_write (in context of the protocol stack) 462 */ 463void st_tx_wakeup(struct st_data_s *st_data) 464{ 465 struct sk_buff *skb; 466 unsigned long flags; /* for irq save flags */ 467 pr_debug("%s", __func__); 468 /* check for sending & set flag sending here */ 469 if (test_and_set_bit(ST_TX_SENDING, &st_data->tx_state)) { 470 pr_debug("ST already sending"); 471 /* keep sending */ 472 set_bit(ST_TX_WAKEUP, &st_data->tx_state); 473 return; 474 /* TX_WAKEUP will be checked in another 475 * context 476 */ 477 } 478 do { /* come back if st_tx_wakeup is set */ 479 /* woke-up to write */ 480 clear_bit(ST_TX_WAKEUP, &st_data->tx_state); 481 while ((skb = st_int_dequeue(st_data))) { 482 int len; 483 spin_lock_irqsave(&st_data->lock, flags); 484 /* enable wake-up from TTY */ 485 set_bit(TTY_DO_WRITE_WAKEUP, &st_data->tty->flags); 486 len = st_int_write(st_data, skb->data, skb->len); 487 skb_pull(skb, len); 488 /* if skb->len = len as expected, skb->len=0 */ 489 if (skb->len) { 490 /* would be the next skb to be sent */ 491 st_data->tx_skb = skb; 492 spin_unlock_irqrestore(&st_data->lock, flags); 493 break; 494 } 495 kfree_skb(skb); 496 spin_unlock_irqrestore(&st_data->lock, flags); 497 } 498 /* if wake-up is set in another context- restart sending */ 499 } while (test_bit(ST_TX_WAKEUP, &st_data->tx_state)); 500 501 /* clear flag sending */ 502 clear_bit(ST_TX_SENDING, &st_data->tx_state); 503} 504 505/********************************************************************/ 506/* functions called from ST KIM 507*/ 508void kim_st_list_protocols(struct st_data_s *st_gdata, void *buf) 509{ 510 seq_printf(buf, "[%d]\nBT=%c\nFM=%c\nGPS=%c\n", 511 st_gdata->protos_registered, 512 st_gdata->is_registered[0x04] == true ? 'R' : 'U', 513 st_gdata->is_registered[0x08] == true ? 'R' : 'U', 514 st_gdata->is_registered[0x09] == true ? 'R' : 'U'); 515} 516 517/********************************************************************/ 518/* 519 * functions called from protocol stack drivers 520 * to be EXPORT-ed 521 */ 522long st_register(struct st_proto_s *new_proto) 523{ 524 struct st_data_s *st_gdata; 525 long err = 0; 526 unsigned long flags = 0; 527 528 st_kim_ref(&st_gdata, 0); 529 if (st_gdata == NULL || new_proto == NULL || new_proto->recv == NULL 530 || new_proto->reg_complete_cb == NULL) { 531 pr_err("gdata/new_proto/recv or reg_complete_cb not ready"); 532 return -EINVAL; 533 } 534 535 if (new_proto->chnl_id >= ST_MAX_CHANNELS) { 536 pr_err("chnl_id %d not supported", new_proto->chnl_id); 537 return -EPROTONOSUPPORT; 538 } 539 540 if (st_gdata->is_registered[new_proto->chnl_id] == true) { 541 pr_err("chnl_id %d already registered", new_proto->chnl_id); 542 return -EALREADY; 543 } 544 545 /* can be from process context only */ 546 spin_lock_irqsave(&st_gdata->lock, flags); 547 548 if (test_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state)) { 549 pr_info(" ST_REG_IN_PROGRESS:%d ", new_proto->chnl_id); 550 /* fw download in progress */ 551 552 add_channel_to_table(st_gdata, new_proto); 553 st_gdata->protos_registered++; 554 new_proto->write = st_write; 555 556 set_bit(ST_REG_PENDING, &st_gdata->st_state); 557 spin_unlock_irqrestore(&st_gdata->lock, flags); 558 return -EINPROGRESS; 559 } else if (st_gdata->protos_registered == ST_EMPTY) { 560 pr_info(" chnl_id list empty :%d ", new_proto->chnl_id); 561 set_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); 562 st_recv = st_kim_recv; 563 564 /* enable the ST LL - to set default chip state */ 565 st_ll_enable(st_gdata); 566 567 /* release lock previously held - re-locked below */ 568 spin_unlock_irqrestore(&st_gdata->lock, flags); 569 570 /* this may take a while to complete 571 * since it involves BT fw download 572 */ 573 err = st_kim_start(st_gdata->kim_data); 574 if (err != 0) { 575 clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); 576 if ((st_gdata->protos_registered != ST_EMPTY) && 577 (test_bit(ST_REG_PENDING, &st_gdata->st_state))) { 578 pr_err(" KIM failure complete callback "); 579 spin_lock_irqsave(&st_gdata->lock, flags); 580 st_reg_complete(st_gdata, err); 581 spin_unlock_irqrestore(&st_gdata->lock, flags); 582 clear_bit(ST_REG_PENDING, &st_gdata->st_state); 583 } 584 return -EINVAL; 585 } 586 587 spin_lock_irqsave(&st_gdata->lock, flags); 588 589 clear_bit(ST_REG_IN_PROGRESS, &st_gdata->st_state); 590 st_recv = st_int_recv; 591 592 /* this is where all pending registration 593 * are signalled to be complete by calling callback functions 594 */ 595 if ((st_gdata->protos_registered != ST_EMPTY) && 596 (test_bit(ST_REG_PENDING, &st_gdata->st_state))) { 597 pr_debug(" call reg complete callback "); 598 st_reg_complete(st_gdata, 0); 599 } 600 clear_bit(ST_REG_PENDING, &st_gdata->st_state); 601 602 /* check for already registered once more, 603 * since the above check is old 604 */ 605 if (st_gdata->is_registered[new_proto->chnl_id] == true) { 606 pr_err(" proto %d already registered ", 607 new_proto->chnl_id); 608 spin_unlock_irqrestore(&st_gdata->lock, flags); 609 return -EALREADY; 610 } 611 612 add_channel_to_table(st_gdata, new_proto); 613 st_gdata->protos_registered++; 614 new_proto->write = st_write; 615 spin_unlock_irqrestore(&st_gdata->lock, flags); 616 return err; 617 } 618 /* if fw is already downloaded & new stack registers protocol */ 619 else { 620 add_channel_to_table(st_gdata, new_proto); 621 st_gdata->protos_registered++; 622 new_proto->write = st_write; 623 624 /* lock already held before entering else */ 625 spin_unlock_irqrestore(&st_gdata->lock, flags); 626 return err; 627 } 628 pr_debug("done %s(%d) ", __func__, new_proto->chnl_id); 629} 630EXPORT_SYMBOL_GPL(st_register); 631 632/* to unregister a protocol - 633 * to be called from protocol stack driver 634 */ 635long st_unregister(struct st_proto_s *proto) 636{ 637 long err = 0; 638 unsigned long flags = 0; 639 struct st_data_s *st_gdata; 640 641 pr_debug("%s: %d ", __func__, proto->chnl_id); 642 643 st_kim_ref(&st_gdata, 0); 644 if (!st_gdata || proto->chnl_id >= ST_MAX_CHANNELS) { 645 pr_err(" chnl_id %d not supported", proto->chnl_id); 646 return -EPROTONOSUPPORT; 647 } 648 649 spin_lock_irqsave(&st_gdata->lock, flags); 650 651 if (st_gdata->is_registered[proto->chnl_id] == false) { 652 pr_err(" chnl_id %d not registered", proto->chnl_id); 653 spin_unlock_irqrestore(&st_gdata->lock, flags); 654 return -EPROTONOSUPPORT; 655 } 656 657 if (st_gdata->protos_registered) 658 st_gdata->protos_registered--; 659 660 remove_channel_from_table(st_gdata, proto); 661 spin_unlock_irqrestore(&st_gdata->lock, flags); 662 663 if ((st_gdata->protos_registered == ST_EMPTY) && 664 (!test_bit(ST_REG_PENDING, &st_gdata->st_state))) { 665 pr_info(" all chnl_ids unregistered "); 666 667 /* stop traffic on tty */ 668 if (st_gdata->tty) { 669 tty_ldisc_flush(st_gdata->tty); 670 stop_tty(st_gdata->tty); 671 } 672 673 /* all chnl_ids now unregistered */ 674 st_kim_stop(st_gdata->kim_data); 675 /* disable ST LL */ 676 st_ll_disable(st_gdata); 677 } 678 return err; 679} 680 681/* 682 * called in protocol stack drivers 683 * via the write function pointer 684 */ 685long st_write(struct sk_buff *skb) 686{ 687 struct st_data_s *st_gdata; 688 long len; 689 690 st_kim_ref(&st_gdata, 0); 691 if (unlikely(skb == NULL || st_gdata == NULL 692 || st_gdata->tty == NULL)) { 693 pr_err("data/tty unavailable to perform write"); 694 return -EINVAL; 695 } 696 697 pr_debug("%d to be written", skb->len); 698 len = skb->len; 699 700 /* st_ll to decide where to enqueue the skb */ 701 st_int_enqueue(st_gdata, skb); 702 /* wake up */ 703 st_tx_wakeup(st_gdata); 704 705 /* return number of bytes written */ 706 return len; 707} 708 709/* for protocols making use of shared transport */ 710EXPORT_SYMBOL_GPL(st_unregister); 711 712/********************************************************************/ 713/* 714 * functions called from TTY layer 715 */ 716static int st_tty_open(struct tty_struct *tty) 717{ 718 int err = 0; 719 struct st_data_s *st_gdata; 720 pr_info("%s ", __func__); 721 722 st_kim_ref(&st_gdata, 0); 723 st_gdata->tty = tty; 724 tty->disc_data = st_gdata; 725 726 /* don't do an wakeup for now */ 727 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 728 729 /* mem already allocated 730 */ 731 tty->receive_room = 65536; 732 /* Flush any pending characters in the driver and discipline. */ 733 tty_ldisc_flush(tty); 734 tty_driver_flush_buffer(tty); 735 /* 736 * signal to UIM via KIM that - 737 * installation of N_TI_WL ldisc is complete 738 */ 739 st_kim_complete(st_gdata->kim_data); 740 pr_debug("done %s", __func__); 741 return err; 742} 743 744static void st_tty_close(struct tty_struct *tty) 745{ 746 unsigned char i = ST_MAX_CHANNELS; 747 unsigned long flags = 0; 748 struct st_data_s *st_gdata = tty->disc_data; 749 750 pr_info("%s ", __func__); 751 752 /* TODO: 753 * if a protocol has been registered & line discipline 754 * un-installed for some reason - what should be done ? 755 */ 756 spin_lock_irqsave(&st_gdata->lock, flags); 757 for (i = ST_BT; i < ST_MAX_CHANNELS; i++) { 758 if (st_gdata->is_registered[i] == true) 759 pr_err("%d not un-registered", i); 760 st_gdata->list[i] = NULL; 761 st_gdata->is_registered[i] = false; 762 } 763 st_gdata->protos_registered = 0; 764 spin_unlock_irqrestore(&st_gdata->lock, flags); 765 /* 766 * signal to UIM via KIM that - 767 * N_TI_WL ldisc is un-installed 768 */ 769 st_kim_complete(st_gdata->kim_data); 770 st_gdata->tty = NULL; 771 /* Flush any pending characters in the driver and discipline. */ 772 tty_ldisc_flush(tty); 773 tty_driver_flush_buffer(tty); 774 775 spin_lock_irqsave(&st_gdata->lock, flags); 776 /* empty out txq and tx_waitq */ 777 skb_queue_purge(&st_gdata->txq); 778 skb_queue_purge(&st_gdata->tx_waitq); 779 /* reset the TTY Rx states of ST */ 780 st_gdata->rx_count = 0; 781 st_gdata->rx_state = ST_W4_PACKET_TYPE; 782 kfree_skb(st_gdata->rx_skb); 783 st_gdata->rx_skb = NULL; 784 spin_unlock_irqrestore(&st_gdata->lock, flags); 785 786 pr_debug("%s: done ", __func__); 787} 788 789static void st_tty_receive(struct tty_struct *tty, const unsigned char *data, 790 char *tty_flags, int count) 791{ 792#ifdef VERBOSE 793 print_hex_dump(KERN_DEBUG, ">in>", DUMP_PREFIX_NONE, 794 16, 1, data, count, 0); 795#endif 796 797 /* 798 * if fw download is in progress then route incoming data 799 * to KIM for validation 800 */ 801 st_recv(tty->disc_data, data, count); 802 pr_debug("done %s", __func__); 803} 804 805/* wake-up function called in from the TTY layer 806 * inside the internal wakeup function will be called 807 */ 808static void st_tty_wakeup(struct tty_struct *tty) 809{ 810 struct st_data_s *st_gdata = tty->disc_data; 811 pr_debug("%s ", __func__); 812 /* don't do an wakeup for now */ 813 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 814 815 /* call our internal wakeup */ 816 st_tx_wakeup((void *)st_gdata); 817} 818 819static void st_tty_flush_buffer(struct tty_struct *tty) 820{ 821 struct st_data_s *st_gdata = tty->disc_data; 822 pr_debug("%s ", __func__); 823 824 kfree_skb(st_gdata->tx_skb); 825 st_gdata->tx_skb = NULL; 826 827 tty_driver_flush_buffer(tty); 828 return; 829} 830 831static struct tty_ldisc_ops st_ldisc_ops = { 832 .magic = TTY_LDISC_MAGIC, 833 .name = "n_st", 834 .open = st_tty_open, 835 .close = st_tty_close, 836 .receive_buf = st_tty_receive, 837 .write_wakeup = st_tty_wakeup, 838 .flush_buffer = st_tty_flush_buffer, 839 .owner = THIS_MODULE 840}; 841 842/********************************************************************/ 843int st_core_init(struct st_data_s **core_data) 844{ 845 struct st_data_s *st_gdata; 846 long err; 847 848 err = tty_register_ldisc(N_TI_WL, &st_ldisc_ops); 849 if (err) { 850 pr_err("error registering %d line discipline %ld", 851 N_TI_WL, err); 852 return err; 853 } 854 pr_debug("registered n_shared line discipline"); 855 856 st_gdata = kzalloc(sizeof(struct st_data_s), GFP_KERNEL); 857 if (!st_gdata) { 858 pr_err("memory allocation failed"); 859 err = tty_unregister_ldisc(N_TI_WL); 860 if (err) 861 pr_err("unable to un-register ldisc %ld", err); 862 err = -ENOMEM; 863 return err; 864 } 865 866 /* Initialize ST TxQ and Tx waitQ queue head. All BT/FM/GPS module skb's 867 * will be pushed in this queue for actual transmission. 868 */ 869 skb_queue_head_init(&st_gdata->txq); 870 skb_queue_head_init(&st_gdata->tx_waitq); 871 872 /* Locking used in st_int_enqueue() to avoid multiple execution */ 873 spin_lock_init(&st_gdata->lock); 874 875 err = st_ll_init(st_gdata); 876 if (err) { 877 pr_err("error during st_ll initialization(%ld)", err); 878 kfree(st_gdata); 879 err = tty_unregister_ldisc(N_TI_WL); 880 if (err) 881 pr_err("unable to un-register ldisc"); 882 return err; 883 } 884 *core_data = st_gdata; 885 return 0; 886} 887 888void st_core_exit(struct st_data_s *st_gdata) 889{ 890 long err; 891 /* internal module cleanup */ 892 err = st_ll_deinit(st_gdata); 893 if (err) 894 pr_err("error during deinit of ST LL %ld", err); 895 896 if (st_gdata != NULL) { 897 /* Free ST Tx Qs and skbs */ 898 skb_queue_purge(&st_gdata->txq); 899 skb_queue_purge(&st_gdata->tx_waitq); 900 kfree_skb(st_gdata->rx_skb); 901 kfree_skb(st_gdata->tx_skb); 902 /* TTY ldisc cleanup */ 903 err = tty_unregister_ldisc(N_TI_WL); 904 if (err) 905 pr_err("unable to un-register ldisc %ld", err); 906 /* free the global data pointer */ 907 kfree(st_gdata); 908 } 909} 910