1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * ssi_protocol.c 4 * 5 * Implementation of the SSI McSAAB improved protocol. 6 * 7 * Copyright (C) 2010 Nokia Corporation. All rights reserved. 8 * Copyright (C) 2013 Sebastian Reichel <sre@kernel.org> 9 * 10 * Contact: Carlos Chinea <carlos.chinea@nokia.com> 11 */ 12 13#include <linux/atomic.h> 14#include <linux/clk.h> 15#include <linux/device.h> 16#include <linux/err.h> 17#include <linux/gpio.h> 18#include <linux/if_ether.h> 19#include <linux/if_arp.h> 20#include <linux/if_phonet.h> 21#include <linux/init.h> 22#include <linux/irq.h> 23#include <linux/list.h> 24#include <linux/module.h> 25#include <linux/netdevice.h> 26#include <linux/notifier.h> 27#include <linux/scatterlist.h> 28#include <linux/skbuff.h> 29#include <linux/slab.h> 30#include <linux/spinlock.h> 31#include <linux/timer.h> 32#include <linux/hsi/hsi.h> 33#include <linux/hsi/ssi_protocol.h> 34 35void ssi_waketest(struct hsi_client *cl, unsigned int enable); 36 37#define SSIP_TXQUEUE_LEN 100 38#define SSIP_MAX_MTU 65535 39#define SSIP_DEFAULT_MTU 4000 40#define PN_MEDIA_SOS 21 41#define SSIP_MIN_PN_HDR 6 /* FIXME: Revisit */ 42#define SSIP_WDTOUT 2000 /* FIXME: has to be 500 msecs */ 43#define SSIP_KATOUT 15 /* 15 msecs */ 44#define SSIP_MAX_CMDS 5 /* Number of pre-allocated commands buffers */ 45#define SSIP_BYTES_TO_FRAMES(x) ((((x) - 1) >> 2) + 1) 46#define SSIP_CMT_LOADER_SYNC 0x11223344 47/* 48 * SSI protocol command definitions 49 */ 50#define SSIP_COMMAND(data) ((data) >> 28) 51#define SSIP_PAYLOAD(data) ((data) & 0xfffffff) 52/* Commands */ 53#define SSIP_SW_BREAK 0 54#define SSIP_BOOTINFO_REQ 1 55#define SSIP_BOOTINFO_RESP 2 56#define SSIP_WAKETEST_RESULT 3 57#define SSIP_START_TRANS 4 58#define SSIP_READY 5 59/* Payloads */ 60#define SSIP_DATA_VERSION(data) ((data) & 0xff) 61#define SSIP_LOCAL_VERID 1 62#define SSIP_WAKETEST_OK 0 63#define SSIP_WAKETEST_FAILED 1 64#define SSIP_PDU_LENGTH(data) (((data) >> 8) & 0xffff) 65#define SSIP_MSG_ID(data) ((data) & 0xff) 66/* Generic Command */ 67#define SSIP_CMD(cmd, payload) (((cmd) << 28) | ((payload) & 0xfffffff)) 68/* Commands for the control channel */ 69#define SSIP_BOOTINFO_REQ_CMD(ver) \ 70 SSIP_CMD(SSIP_BOOTINFO_REQ, SSIP_DATA_VERSION(ver)) 71#define SSIP_BOOTINFO_RESP_CMD(ver) \ 72 SSIP_CMD(SSIP_BOOTINFO_RESP, SSIP_DATA_VERSION(ver)) 73#define SSIP_START_TRANS_CMD(pdulen, id) \ 74 SSIP_CMD(SSIP_START_TRANS, (((pdulen) << 8) | SSIP_MSG_ID(id))) 75#define SSIP_READY_CMD SSIP_CMD(SSIP_READY, 0) 76#define SSIP_SWBREAK_CMD SSIP_CMD(SSIP_SW_BREAK, 0) 77 78#define SSIP_WAKETEST_FLAG 0 79 80/* Main state machine states */ 81enum { 82 INIT, 83 HANDSHAKE, 84 ACTIVE, 85}; 86 87/* Send state machine states */ 88enum { 89 SEND_IDLE, 90 WAIT4READY, 91 SEND_READY, 92 SENDING, 93 SENDING_SWBREAK, 94}; 95 96/* Receive state machine states */ 97enum { 98 RECV_IDLE, 99 RECV_READY, 100 RECEIVING, 101}; 102 103/** 104 * struct ssi_protocol - SSI protocol (McSAAB) data 105 * @main_state: Main state machine 106 * @send_state: TX state machine 107 * @recv_state: RX state machine 108 * @flags: Flags, currently only used to follow wake line test 109 * @rxid: RX data id 110 * @txid: TX data id 111 * @txqueue_len: TX queue length 112 * @tx_wd: TX watchdog 113 * @rx_wd: RX watchdog 114 * @keep_alive: Workaround for SSI HW bug 115 * @lock: To serialize access to this struct 116 * @netdev: Phonet network device 117 * @txqueue: TX data queue 118 * @cmdqueue: Queue of free commands 119 * @cl: HSI client own reference 120 * @link: Link for ssip_list 121 * @tx_usecount: Refcount to keep track the slaves that use the wake line 122 * @channel_id_cmd: HSI channel id for command stream 123 * @channel_id_data: HSI channel id for data stream 124 */ 125struct ssi_protocol { 126 unsigned int main_state; 127 unsigned int send_state; 128 unsigned int recv_state; 129 unsigned long flags; 130 u8 rxid; 131 u8 txid; 132 unsigned int txqueue_len; 133 struct timer_list tx_wd; 134 struct timer_list rx_wd; 135 struct timer_list keep_alive; /* wake-up workaround */ 136 spinlock_t lock; 137 struct net_device *netdev; 138 struct list_head txqueue; 139 struct list_head cmdqueue; 140 struct work_struct work; 141 struct hsi_client *cl; 142 struct list_head link; 143 atomic_t tx_usecnt; 144 int channel_id_cmd; 145 int channel_id_data; 146}; 147 148/* List of ssi protocol instances */ 149static LIST_HEAD(ssip_list); 150 151static void ssip_rxcmd_complete(struct hsi_msg *msg); 152 153static inline void ssip_set_cmd(struct hsi_msg *msg, u32 cmd) 154{ 155 u32 *data; 156 157 data = sg_virt(msg->sgt.sgl); 158 *data = cmd; 159} 160 161static inline u32 ssip_get_cmd(struct hsi_msg *msg) 162{ 163 u32 *data; 164 165 data = sg_virt(msg->sgt.sgl); 166 167 return *data; 168} 169 170static void ssip_skb_to_msg(struct sk_buff *skb, struct hsi_msg *msg) 171{ 172 skb_frag_t *frag; 173 struct scatterlist *sg; 174 int i; 175 176 BUG_ON(msg->sgt.nents != (unsigned int)(skb_shinfo(skb)->nr_frags + 1)); 177 178 sg = msg->sgt.sgl; 179 sg_set_buf(sg, skb->data, skb_headlen(skb)); 180 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 181 sg = sg_next(sg); 182 BUG_ON(!sg); 183 frag = &skb_shinfo(skb)->frags[i]; 184 sg_set_page(sg, skb_frag_page(frag), skb_frag_size(frag), 185 skb_frag_off(frag)); 186 } 187} 188 189static void ssip_free_data(struct hsi_msg *msg) 190{ 191 struct sk_buff *skb; 192 193 skb = msg->context; 194 pr_debug("free data: msg %p context %p skb %p\n", msg, msg->context, 195 skb); 196 msg->destructor = NULL; 197 dev_kfree_skb(skb); 198 hsi_free_msg(msg); 199} 200 201static struct hsi_msg *ssip_alloc_data(struct ssi_protocol *ssi, 202 struct sk_buff *skb, gfp_t flags) 203{ 204 struct hsi_msg *msg; 205 206 msg = hsi_alloc_msg(skb_shinfo(skb)->nr_frags + 1, flags); 207 if (!msg) 208 return NULL; 209 ssip_skb_to_msg(skb, msg); 210 msg->destructor = ssip_free_data; 211 msg->channel = ssi->channel_id_data; 212 msg->context = skb; 213 214 return msg; 215} 216 217static inline void ssip_release_cmd(struct hsi_msg *msg) 218{ 219 struct ssi_protocol *ssi = hsi_client_drvdata(msg->cl); 220 221 dev_dbg(&msg->cl->device, "Release cmd 0x%08x\n", ssip_get_cmd(msg)); 222 spin_lock_bh(&ssi->lock); 223 list_add_tail(&msg->link, &ssi->cmdqueue); 224 spin_unlock_bh(&ssi->lock); 225} 226 227static struct hsi_msg *ssip_claim_cmd(struct ssi_protocol *ssi) 228{ 229 struct hsi_msg *msg; 230 231 BUG_ON(list_empty(&ssi->cmdqueue)); 232 233 spin_lock_bh(&ssi->lock); 234 msg = list_first_entry(&ssi->cmdqueue, struct hsi_msg, link); 235 list_del(&msg->link); 236 spin_unlock_bh(&ssi->lock); 237 msg->destructor = ssip_release_cmd; 238 239 return msg; 240} 241 242static void ssip_free_cmds(struct ssi_protocol *ssi) 243{ 244 struct hsi_msg *msg, *tmp; 245 246 list_for_each_entry_safe(msg, tmp, &ssi->cmdqueue, link) { 247 list_del(&msg->link); 248 msg->destructor = NULL; 249 kfree(sg_virt(msg->sgt.sgl)); 250 hsi_free_msg(msg); 251 } 252} 253 254static int ssip_alloc_cmds(struct ssi_protocol *ssi) 255{ 256 struct hsi_msg *msg; 257 u32 *buf; 258 unsigned int i; 259 260 for (i = 0; i < SSIP_MAX_CMDS; i++) { 261 msg = hsi_alloc_msg(1, GFP_KERNEL); 262 if (!msg) 263 goto out; 264 buf = kmalloc(sizeof(*buf), GFP_KERNEL); 265 if (!buf) { 266 hsi_free_msg(msg); 267 goto out; 268 } 269 sg_init_one(msg->sgt.sgl, buf, sizeof(*buf)); 270 msg->channel = ssi->channel_id_cmd; 271 list_add_tail(&msg->link, &ssi->cmdqueue); 272 } 273 274 return 0; 275out: 276 ssip_free_cmds(ssi); 277 278 return -ENOMEM; 279} 280 281static void ssip_set_rxstate(struct ssi_protocol *ssi, unsigned int state) 282{ 283 ssi->recv_state = state; 284 switch (state) { 285 case RECV_IDLE: 286 del_timer(&ssi->rx_wd); 287 if (ssi->send_state == SEND_IDLE) 288 del_timer(&ssi->keep_alive); 289 break; 290 case RECV_READY: 291 /* CMT speech workaround */ 292 if (atomic_read(&ssi->tx_usecnt)) 293 break; 294 fallthrough; 295 case RECEIVING: 296 mod_timer(&ssi->keep_alive, jiffies + 297 msecs_to_jiffies(SSIP_KATOUT)); 298 mod_timer(&ssi->rx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT)); 299 break; 300 default: 301 break; 302 } 303} 304 305static void ssip_set_txstate(struct ssi_protocol *ssi, unsigned int state) 306{ 307 ssi->send_state = state; 308 switch (state) { 309 case SEND_IDLE: 310 case SEND_READY: 311 del_timer(&ssi->tx_wd); 312 if (ssi->recv_state == RECV_IDLE) 313 del_timer(&ssi->keep_alive); 314 break; 315 case WAIT4READY: 316 case SENDING: 317 case SENDING_SWBREAK: 318 mod_timer(&ssi->keep_alive, 319 jiffies + msecs_to_jiffies(SSIP_KATOUT)); 320 mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT)); 321 break; 322 default: 323 break; 324 } 325} 326 327struct hsi_client *ssip_slave_get_master(struct hsi_client *slave) 328{ 329 struct hsi_client *master = ERR_PTR(-ENODEV); 330 struct ssi_protocol *ssi; 331 332 list_for_each_entry(ssi, &ssip_list, link) 333 if (slave->device.parent == ssi->cl->device.parent) { 334 master = ssi->cl; 335 break; 336 } 337 338 return master; 339} 340EXPORT_SYMBOL_GPL(ssip_slave_get_master); 341 342int ssip_slave_start_tx(struct hsi_client *master) 343{ 344 struct ssi_protocol *ssi = hsi_client_drvdata(master); 345 346 dev_dbg(&master->device, "start TX %d\n", atomic_read(&ssi->tx_usecnt)); 347 spin_lock_bh(&ssi->lock); 348 if (ssi->send_state == SEND_IDLE) { 349 ssip_set_txstate(ssi, WAIT4READY); 350 hsi_start_tx(master); 351 } 352 spin_unlock_bh(&ssi->lock); 353 atomic_inc(&ssi->tx_usecnt); 354 355 return 0; 356} 357EXPORT_SYMBOL_GPL(ssip_slave_start_tx); 358 359int ssip_slave_stop_tx(struct hsi_client *master) 360{ 361 struct ssi_protocol *ssi = hsi_client_drvdata(master); 362 363 WARN_ON_ONCE(atomic_read(&ssi->tx_usecnt) == 0); 364 365 if (atomic_dec_and_test(&ssi->tx_usecnt)) { 366 spin_lock_bh(&ssi->lock); 367 if ((ssi->send_state == SEND_READY) || 368 (ssi->send_state == WAIT4READY)) { 369 ssip_set_txstate(ssi, SEND_IDLE); 370 hsi_stop_tx(master); 371 } 372 spin_unlock_bh(&ssi->lock); 373 } 374 dev_dbg(&master->device, "stop TX %d\n", atomic_read(&ssi->tx_usecnt)); 375 376 return 0; 377} 378EXPORT_SYMBOL_GPL(ssip_slave_stop_tx); 379 380int ssip_slave_running(struct hsi_client *master) 381{ 382 struct ssi_protocol *ssi = hsi_client_drvdata(master); 383 return netif_running(ssi->netdev); 384} 385EXPORT_SYMBOL_GPL(ssip_slave_running); 386 387static void ssip_reset(struct hsi_client *cl) 388{ 389 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 390 struct list_head *head, *tmp; 391 struct hsi_msg *msg; 392 393 if (netif_running(ssi->netdev)) 394 netif_carrier_off(ssi->netdev); 395 hsi_flush(cl); 396 spin_lock_bh(&ssi->lock); 397 if (ssi->send_state != SEND_IDLE) 398 hsi_stop_tx(cl); 399 spin_unlock_bh(&ssi->lock); 400 if (test_and_clear_bit(SSIP_WAKETEST_FLAG, &ssi->flags)) 401 ssi_waketest(cl, 0); /* FIXME: To be removed */ 402 spin_lock_bh(&ssi->lock); 403 del_timer(&ssi->rx_wd); 404 del_timer(&ssi->tx_wd); 405 del_timer(&ssi->keep_alive); 406 ssi->main_state = 0; 407 ssi->send_state = 0; 408 ssi->recv_state = 0; 409 ssi->flags = 0; 410 ssi->rxid = 0; 411 ssi->txid = 0; 412 list_for_each_safe(head, tmp, &ssi->txqueue) { 413 msg = list_entry(head, struct hsi_msg, link); 414 dev_dbg(&cl->device, "Pending TX data\n"); 415 list_del(head); 416 ssip_free_data(msg); 417 } 418 ssi->txqueue_len = 0; 419 spin_unlock_bh(&ssi->lock); 420} 421 422static void ssip_dump_state(struct hsi_client *cl) 423{ 424 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 425 struct hsi_msg *msg; 426 427 spin_lock_bh(&ssi->lock); 428 dev_err(&cl->device, "Main state: %d\n", ssi->main_state); 429 dev_err(&cl->device, "Recv state: %d\n", ssi->recv_state); 430 dev_err(&cl->device, "Send state: %d\n", ssi->send_state); 431 dev_err(&cl->device, "CMT %s\n", (ssi->main_state == ACTIVE) ? 432 "Online" : "Offline"); 433 dev_err(&cl->device, "Wake test %d\n", 434 test_bit(SSIP_WAKETEST_FLAG, &ssi->flags)); 435 dev_err(&cl->device, "Data RX id: %d\n", ssi->rxid); 436 dev_err(&cl->device, "Data TX id: %d\n", ssi->txid); 437 438 list_for_each_entry(msg, &ssi->txqueue, link) 439 dev_err(&cl->device, "pending TX data (%p)\n", msg); 440 spin_unlock_bh(&ssi->lock); 441} 442 443static void ssip_error(struct hsi_client *cl) 444{ 445 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 446 struct hsi_msg *msg; 447 448 ssip_dump_state(cl); 449 ssip_reset(cl); 450 msg = ssip_claim_cmd(ssi); 451 msg->complete = ssip_rxcmd_complete; 452 hsi_async_read(cl, msg); 453} 454 455static void ssip_keep_alive(struct timer_list *t) 456{ 457 struct ssi_protocol *ssi = from_timer(ssi, t, keep_alive); 458 struct hsi_client *cl = ssi->cl; 459 460 dev_dbg(&cl->device, "Keep alive kick in: m(%d) r(%d) s(%d)\n", 461 ssi->main_state, ssi->recv_state, ssi->send_state); 462 463 spin_lock(&ssi->lock); 464 if (ssi->recv_state == RECV_IDLE) 465 switch (ssi->send_state) { 466 case SEND_READY: 467 if (atomic_read(&ssi->tx_usecnt) == 0) 468 break; 469 fallthrough; 470 /* 471 * Workaround for cmt-speech in that case 472 * we relay on audio timers. 473 */ 474 case SEND_IDLE: 475 spin_unlock(&ssi->lock); 476 return; 477 } 478 mod_timer(&ssi->keep_alive, jiffies + msecs_to_jiffies(SSIP_KATOUT)); 479 spin_unlock(&ssi->lock); 480} 481 482static void ssip_rx_wd(struct timer_list *t) 483{ 484 struct ssi_protocol *ssi = from_timer(ssi, t, rx_wd); 485 struct hsi_client *cl = ssi->cl; 486 487 dev_err(&cl->device, "Watchdog triggered\n"); 488 ssip_error(cl); 489} 490 491static void ssip_tx_wd(struct timer_list *t) 492{ 493 struct ssi_protocol *ssi = from_timer(ssi, t, tx_wd); 494 struct hsi_client *cl = ssi->cl; 495 496 dev_err(&cl->device, "Watchdog triggered\n"); 497 ssip_error(cl); 498} 499 500static void ssip_send_bootinfo_req_cmd(struct hsi_client *cl) 501{ 502 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 503 struct hsi_msg *msg; 504 505 dev_dbg(&cl->device, "Issuing BOOT INFO REQ command\n"); 506 msg = ssip_claim_cmd(ssi); 507 ssip_set_cmd(msg, SSIP_BOOTINFO_REQ_CMD(SSIP_LOCAL_VERID)); 508 msg->complete = ssip_release_cmd; 509 hsi_async_write(cl, msg); 510 dev_dbg(&cl->device, "Issuing RX command\n"); 511 msg = ssip_claim_cmd(ssi); 512 msg->complete = ssip_rxcmd_complete; 513 hsi_async_read(cl, msg); 514} 515 516static void ssip_start_rx(struct hsi_client *cl) 517{ 518 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 519 struct hsi_msg *msg; 520 521 dev_dbg(&cl->device, "RX start M(%d) R(%d)\n", ssi->main_state, 522 ssi->recv_state); 523 spin_lock_bh(&ssi->lock); 524 /* 525 * We can have two UP events in a row due to a short low 526 * high transition. Therefore we need to ignore the sencond UP event. 527 */ 528 if ((ssi->main_state != ACTIVE) || (ssi->recv_state == RECV_READY)) { 529 spin_unlock_bh(&ssi->lock); 530 return; 531 } 532 ssip_set_rxstate(ssi, RECV_READY); 533 spin_unlock_bh(&ssi->lock); 534 535 msg = ssip_claim_cmd(ssi); 536 ssip_set_cmd(msg, SSIP_READY_CMD); 537 msg->complete = ssip_release_cmd; 538 dev_dbg(&cl->device, "Send READY\n"); 539 hsi_async_write(cl, msg); 540} 541 542static void ssip_stop_rx(struct hsi_client *cl) 543{ 544 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 545 546 dev_dbg(&cl->device, "RX stop M(%d)\n", ssi->main_state); 547 spin_lock_bh(&ssi->lock); 548 if (likely(ssi->main_state == ACTIVE)) 549 ssip_set_rxstate(ssi, RECV_IDLE); 550 spin_unlock_bh(&ssi->lock); 551} 552 553static void ssip_free_strans(struct hsi_msg *msg) 554{ 555 ssip_free_data(msg->context); 556 ssip_release_cmd(msg); 557} 558 559static void ssip_strans_complete(struct hsi_msg *msg) 560{ 561 struct hsi_client *cl = msg->cl; 562 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 563 struct hsi_msg *data; 564 565 data = msg->context; 566 ssip_release_cmd(msg); 567 spin_lock_bh(&ssi->lock); 568 ssip_set_txstate(ssi, SENDING); 569 spin_unlock_bh(&ssi->lock); 570 hsi_async_write(cl, data); 571} 572 573static int ssip_xmit(struct hsi_client *cl) 574{ 575 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 576 struct hsi_msg *msg, *dmsg; 577 struct sk_buff *skb; 578 579 spin_lock_bh(&ssi->lock); 580 if (list_empty(&ssi->txqueue)) { 581 spin_unlock_bh(&ssi->lock); 582 return 0; 583 } 584 dmsg = list_first_entry(&ssi->txqueue, struct hsi_msg, link); 585 list_del(&dmsg->link); 586 ssi->txqueue_len--; 587 spin_unlock_bh(&ssi->lock); 588 589 msg = ssip_claim_cmd(ssi); 590 skb = dmsg->context; 591 msg->context = dmsg; 592 msg->complete = ssip_strans_complete; 593 msg->destructor = ssip_free_strans; 594 595 spin_lock_bh(&ssi->lock); 596 ssip_set_cmd(msg, SSIP_START_TRANS_CMD(SSIP_BYTES_TO_FRAMES(skb->len), 597 ssi->txid)); 598 ssi->txid++; 599 ssip_set_txstate(ssi, SENDING); 600 spin_unlock_bh(&ssi->lock); 601 602 dev_dbg(&cl->device, "Send STRANS (%d frames)\n", 603 SSIP_BYTES_TO_FRAMES(skb->len)); 604 605 return hsi_async_write(cl, msg); 606} 607 608/* In soft IRQ context */ 609static void ssip_pn_rx(struct sk_buff *skb) 610{ 611 struct net_device *dev = skb->dev; 612 613 if (unlikely(!netif_running(dev))) { 614 dev_dbg(&dev->dev, "Drop RX packet\n"); 615 dev->stats.rx_dropped++; 616 dev_kfree_skb(skb); 617 return; 618 } 619 if (unlikely(!pskb_may_pull(skb, SSIP_MIN_PN_HDR))) { 620 dev_dbg(&dev->dev, "Error drop RX packet\n"); 621 dev->stats.rx_errors++; 622 dev->stats.rx_length_errors++; 623 dev_kfree_skb(skb); 624 return; 625 } 626 dev->stats.rx_packets++; 627 dev->stats.rx_bytes += skb->len; 628 629 /* length field is exchanged in network byte order */ 630 ((u16 *)skb->data)[2] = ntohs(((u16 *)skb->data)[2]); 631 dev_dbg(&dev->dev, "RX length fixed (%04x -> %u)\n", 632 ((u16 *)skb->data)[2], ntohs(((u16 *)skb->data)[2])); 633 634 skb->protocol = htons(ETH_P_PHONET); 635 skb_reset_mac_header(skb); 636 __skb_pull(skb, 1); 637 netif_rx(skb); 638} 639 640static void ssip_rx_data_complete(struct hsi_msg *msg) 641{ 642 struct hsi_client *cl = msg->cl; 643 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 644 struct sk_buff *skb; 645 646 if (msg->status == HSI_STATUS_ERROR) { 647 dev_err(&cl->device, "RX data error\n"); 648 ssip_free_data(msg); 649 ssip_error(cl); 650 return; 651 } 652 del_timer(&ssi->rx_wd); /* FIXME: Revisit */ 653 skb = msg->context; 654 ssip_pn_rx(skb); 655 hsi_free_msg(msg); 656} 657 658static void ssip_rx_bootinforeq(struct hsi_client *cl, u32 cmd) 659{ 660 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 661 struct hsi_msg *msg; 662 663 /* Workaroud: Ignore CMT Loader message leftover */ 664 if (cmd == SSIP_CMT_LOADER_SYNC) 665 return; 666 667 switch (ssi->main_state) { 668 case ACTIVE: 669 dev_err(&cl->device, "Boot info req on active state\n"); 670 ssip_error(cl); 671 fallthrough; 672 case INIT: 673 case HANDSHAKE: 674 spin_lock_bh(&ssi->lock); 675 ssi->main_state = HANDSHAKE; 676 spin_unlock_bh(&ssi->lock); 677 678 if (!test_and_set_bit(SSIP_WAKETEST_FLAG, &ssi->flags)) 679 ssi_waketest(cl, 1); /* FIXME: To be removed */ 680 681 spin_lock_bh(&ssi->lock); 682 /* Start boot handshake watchdog */ 683 mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT)); 684 spin_unlock_bh(&ssi->lock); 685 dev_dbg(&cl->device, "Send BOOTINFO_RESP\n"); 686 if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID) 687 dev_warn(&cl->device, "boot info req verid mismatch\n"); 688 msg = ssip_claim_cmd(ssi); 689 ssip_set_cmd(msg, SSIP_BOOTINFO_RESP_CMD(SSIP_LOCAL_VERID)); 690 msg->complete = ssip_release_cmd; 691 hsi_async_write(cl, msg); 692 break; 693 default: 694 dev_dbg(&cl->device, "Wrong state M(%d)\n", ssi->main_state); 695 break; 696 } 697} 698 699static void ssip_rx_bootinforesp(struct hsi_client *cl, u32 cmd) 700{ 701 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 702 703 if (SSIP_DATA_VERSION(cmd) != SSIP_LOCAL_VERID) 704 dev_warn(&cl->device, "boot info resp verid mismatch\n"); 705 706 spin_lock_bh(&ssi->lock); 707 if (ssi->main_state != ACTIVE) 708 /* Use tx_wd as a boot watchdog in non ACTIVE state */ 709 mod_timer(&ssi->tx_wd, jiffies + msecs_to_jiffies(SSIP_WDTOUT)); 710 else 711 dev_dbg(&cl->device, "boot info resp ignored M(%d)\n", 712 ssi->main_state); 713 spin_unlock_bh(&ssi->lock); 714} 715 716static void ssip_rx_waketest(struct hsi_client *cl, u32 cmd) 717{ 718 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 719 unsigned int wkres = SSIP_PAYLOAD(cmd); 720 721 spin_lock_bh(&ssi->lock); 722 if (ssi->main_state != HANDSHAKE) { 723 dev_dbg(&cl->device, "wake lines test ignored M(%d)\n", 724 ssi->main_state); 725 spin_unlock_bh(&ssi->lock); 726 return; 727 } 728 spin_unlock_bh(&ssi->lock); 729 730 if (test_and_clear_bit(SSIP_WAKETEST_FLAG, &ssi->flags)) 731 ssi_waketest(cl, 0); /* FIXME: To be removed */ 732 733 spin_lock_bh(&ssi->lock); 734 ssi->main_state = ACTIVE; 735 del_timer(&ssi->tx_wd); /* Stop boot handshake timer */ 736 spin_unlock_bh(&ssi->lock); 737 738 dev_notice(&cl->device, "WAKELINES TEST %s\n", 739 wkres & SSIP_WAKETEST_FAILED ? "FAILED" : "OK"); 740 if (wkres & SSIP_WAKETEST_FAILED) { 741 ssip_error(cl); 742 return; 743 } 744 dev_dbg(&cl->device, "CMT is ONLINE\n"); 745 netif_wake_queue(ssi->netdev); 746 netif_carrier_on(ssi->netdev); 747} 748 749static void ssip_rx_ready(struct hsi_client *cl) 750{ 751 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 752 753 spin_lock_bh(&ssi->lock); 754 if (unlikely(ssi->main_state != ACTIVE)) { 755 dev_dbg(&cl->device, "READY on wrong state: S(%d) M(%d)\n", 756 ssi->send_state, ssi->main_state); 757 spin_unlock_bh(&ssi->lock); 758 return; 759 } 760 if (ssi->send_state != WAIT4READY) { 761 dev_dbg(&cl->device, "Ignore spurious READY command\n"); 762 spin_unlock_bh(&ssi->lock); 763 return; 764 } 765 ssip_set_txstate(ssi, SEND_READY); 766 spin_unlock_bh(&ssi->lock); 767 ssip_xmit(cl); 768} 769 770static void ssip_rx_strans(struct hsi_client *cl, u32 cmd) 771{ 772 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 773 struct sk_buff *skb; 774 struct hsi_msg *msg; 775 int len = SSIP_PDU_LENGTH(cmd); 776 777 dev_dbg(&cl->device, "RX strans: %d frames\n", len); 778 spin_lock_bh(&ssi->lock); 779 if (unlikely(ssi->main_state != ACTIVE)) { 780 dev_err(&cl->device, "START TRANS wrong state: S(%d) M(%d)\n", 781 ssi->send_state, ssi->main_state); 782 spin_unlock_bh(&ssi->lock); 783 return; 784 } 785 ssip_set_rxstate(ssi, RECEIVING); 786 if (unlikely(SSIP_MSG_ID(cmd) != ssi->rxid)) { 787 dev_err(&cl->device, "START TRANS id %d expected %d\n", 788 SSIP_MSG_ID(cmd), ssi->rxid); 789 spin_unlock_bh(&ssi->lock); 790 goto out1; 791 } 792 ssi->rxid++; 793 spin_unlock_bh(&ssi->lock); 794 skb = netdev_alloc_skb(ssi->netdev, len * 4); 795 if (unlikely(!skb)) { 796 dev_err(&cl->device, "No memory for rx skb\n"); 797 goto out1; 798 } 799 skb->dev = ssi->netdev; 800 skb_put(skb, len * 4); 801 msg = ssip_alloc_data(ssi, skb, GFP_ATOMIC); 802 if (unlikely(!msg)) { 803 dev_err(&cl->device, "No memory for RX data msg\n"); 804 goto out2; 805 } 806 msg->complete = ssip_rx_data_complete; 807 hsi_async_read(cl, msg); 808 809 return; 810out2: 811 dev_kfree_skb(skb); 812out1: 813 ssip_error(cl); 814} 815 816static void ssip_rxcmd_complete(struct hsi_msg *msg) 817{ 818 struct hsi_client *cl = msg->cl; 819 u32 cmd = ssip_get_cmd(msg); 820 unsigned int cmdid = SSIP_COMMAND(cmd); 821 822 if (msg->status == HSI_STATUS_ERROR) { 823 dev_err(&cl->device, "RX error detected\n"); 824 ssip_release_cmd(msg); 825 ssip_error(cl); 826 return; 827 } 828 hsi_async_read(cl, msg); 829 dev_dbg(&cl->device, "RX cmd: 0x%08x\n", cmd); 830 switch (cmdid) { 831 case SSIP_SW_BREAK: 832 /* Ignored */ 833 break; 834 case SSIP_BOOTINFO_REQ: 835 ssip_rx_bootinforeq(cl, cmd); 836 break; 837 case SSIP_BOOTINFO_RESP: 838 ssip_rx_bootinforesp(cl, cmd); 839 break; 840 case SSIP_WAKETEST_RESULT: 841 ssip_rx_waketest(cl, cmd); 842 break; 843 case SSIP_START_TRANS: 844 ssip_rx_strans(cl, cmd); 845 break; 846 case SSIP_READY: 847 ssip_rx_ready(cl); 848 break; 849 default: 850 dev_warn(&cl->device, "command 0x%08x not supported\n", cmd); 851 break; 852 } 853} 854 855static void ssip_swbreak_complete(struct hsi_msg *msg) 856{ 857 struct hsi_client *cl = msg->cl; 858 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 859 860 ssip_release_cmd(msg); 861 spin_lock_bh(&ssi->lock); 862 if (list_empty(&ssi->txqueue)) { 863 if (atomic_read(&ssi->tx_usecnt)) { 864 ssip_set_txstate(ssi, SEND_READY); 865 } else { 866 ssip_set_txstate(ssi, SEND_IDLE); 867 hsi_stop_tx(cl); 868 } 869 spin_unlock_bh(&ssi->lock); 870 } else { 871 spin_unlock_bh(&ssi->lock); 872 ssip_xmit(cl); 873 } 874 netif_wake_queue(ssi->netdev); 875} 876 877static void ssip_tx_data_complete(struct hsi_msg *msg) 878{ 879 struct hsi_client *cl = msg->cl; 880 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 881 struct hsi_msg *cmsg; 882 883 if (msg->status == HSI_STATUS_ERROR) { 884 dev_err(&cl->device, "TX data error\n"); 885 ssip_error(cl); 886 goto out; 887 } 888 spin_lock_bh(&ssi->lock); 889 if (list_empty(&ssi->txqueue)) { 890 ssip_set_txstate(ssi, SENDING_SWBREAK); 891 spin_unlock_bh(&ssi->lock); 892 cmsg = ssip_claim_cmd(ssi); 893 ssip_set_cmd(cmsg, SSIP_SWBREAK_CMD); 894 cmsg->complete = ssip_swbreak_complete; 895 dev_dbg(&cl->device, "Send SWBREAK\n"); 896 hsi_async_write(cl, cmsg); 897 } else { 898 spin_unlock_bh(&ssi->lock); 899 ssip_xmit(cl); 900 } 901out: 902 ssip_free_data(msg); 903} 904 905static void ssip_port_event(struct hsi_client *cl, unsigned long event) 906{ 907 switch (event) { 908 case HSI_EVENT_START_RX: 909 ssip_start_rx(cl); 910 break; 911 case HSI_EVENT_STOP_RX: 912 ssip_stop_rx(cl); 913 break; 914 default: 915 return; 916 } 917} 918 919static int ssip_pn_open(struct net_device *dev) 920{ 921 struct hsi_client *cl = to_hsi_client(dev->dev.parent); 922 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 923 int err; 924 925 err = hsi_claim_port(cl, 1); 926 if (err < 0) { 927 dev_err(&cl->device, "SSI port already claimed\n"); 928 return err; 929 } 930 err = hsi_register_port_event(cl, ssip_port_event); 931 if (err < 0) { 932 dev_err(&cl->device, "Register HSI port event failed (%d)\n", 933 err); 934 return err; 935 } 936 dev_dbg(&cl->device, "Configuring SSI port\n"); 937 hsi_setup(cl); 938 939 if (!test_and_set_bit(SSIP_WAKETEST_FLAG, &ssi->flags)) 940 ssi_waketest(cl, 1); /* FIXME: To be removed */ 941 942 spin_lock_bh(&ssi->lock); 943 ssi->main_state = HANDSHAKE; 944 spin_unlock_bh(&ssi->lock); 945 946 ssip_send_bootinfo_req_cmd(cl); 947 948 return 0; 949} 950 951static int ssip_pn_stop(struct net_device *dev) 952{ 953 struct hsi_client *cl = to_hsi_client(dev->dev.parent); 954 955 ssip_reset(cl); 956 hsi_unregister_port_event(cl); 957 hsi_release_port(cl); 958 959 return 0; 960} 961 962static void ssip_xmit_work(struct work_struct *work) 963{ 964 struct ssi_protocol *ssi = 965 container_of(work, struct ssi_protocol, work); 966 struct hsi_client *cl = ssi->cl; 967 968 ssip_xmit(cl); 969} 970 971static int ssip_pn_xmit(struct sk_buff *skb, struct net_device *dev) 972{ 973 struct hsi_client *cl = to_hsi_client(dev->dev.parent); 974 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 975 struct hsi_msg *msg; 976 977 if ((skb->protocol != htons(ETH_P_PHONET)) || 978 (skb->len < SSIP_MIN_PN_HDR)) 979 goto drop; 980 /* Pad to 32-bits - FIXME: Revisit*/ 981 if ((skb->len & 3) && skb_pad(skb, 4 - (skb->len & 3))) 982 goto inc_dropped; 983 984 /* 985 * Modem sends Phonet messages over SSI with its own endianness. 986 * Assume that modem has the same endianness as we do. 987 */ 988 if (skb_cow_head(skb, 0)) 989 goto drop; 990 991 /* length field is exchanged in network byte order */ 992 ((u16 *)skb->data)[2] = htons(((u16 *)skb->data)[2]); 993 994 msg = ssip_alloc_data(ssi, skb, GFP_ATOMIC); 995 if (!msg) { 996 dev_dbg(&cl->device, "Dropping tx data: No memory\n"); 997 goto drop; 998 } 999 msg->complete = ssip_tx_data_complete; 1000 1001 spin_lock_bh(&ssi->lock); 1002 if (unlikely(ssi->main_state != ACTIVE)) { 1003 spin_unlock_bh(&ssi->lock); 1004 dev_dbg(&cl->device, "Dropping tx data: CMT is OFFLINE\n"); 1005 goto drop2; 1006 } 1007 list_add_tail(&msg->link, &ssi->txqueue); 1008 ssi->txqueue_len++; 1009 if (dev->tx_queue_len < ssi->txqueue_len) { 1010 dev_info(&cl->device, "TX queue full %d\n", ssi->txqueue_len); 1011 netif_stop_queue(dev); 1012 } 1013 if (ssi->send_state == SEND_IDLE) { 1014 ssip_set_txstate(ssi, WAIT4READY); 1015 spin_unlock_bh(&ssi->lock); 1016 dev_dbg(&cl->device, "Start TX qlen %d\n", ssi->txqueue_len); 1017 hsi_start_tx(cl); 1018 } else if (ssi->send_state == SEND_READY) { 1019 /* Needed for cmt-speech workaround */ 1020 dev_dbg(&cl->device, "Start TX on SEND READY qlen %d\n", 1021 ssi->txqueue_len); 1022 spin_unlock_bh(&ssi->lock); 1023 schedule_work(&ssi->work); 1024 } else { 1025 spin_unlock_bh(&ssi->lock); 1026 } 1027 dev->stats.tx_packets++; 1028 dev->stats.tx_bytes += skb->len; 1029 1030 return 0; 1031drop2: 1032 hsi_free_msg(msg); 1033drop: 1034 dev_kfree_skb(skb); 1035inc_dropped: 1036 dev->stats.tx_dropped++; 1037 1038 return 0; 1039} 1040 1041/* CMT reset event handler */ 1042void ssip_reset_event(struct hsi_client *master) 1043{ 1044 struct ssi_protocol *ssi = hsi_client_drvdata(master); 1045 dev_err(&ssi->cl->device, "CMT reset detected!\n"); 1046 ssip_error(ssi->cl); 1047} 1048EXPORT_SYMBOL_GPL(ssip_reset_event); 1049 1050static const struct net_device_ops ssip_pn_ops = { 1051 .ndo_open = ssip_pn_open, 1052 .ndo_stop = ssip_pn_stop, 1053 .ndo_start_xmit = ssip_pn_xmit, 1054}; 1055 1056static void ssip_pn_setup(struct net_device *dev) 1057{ 1058 dev->features = 0; 1059 dev->netdev_ops = &ssip_pn_ops; 1060 dev->type = ARPHRD_PHONET; 1061 dev->flags = IFF_POINTOPOINT | IFF_NOARP; 1062 dev->mtu = SSIP_DEFAULT_MTU; 1063 dev->hard_header_len = 1; 1064 dev->dev_addr[0] = PN_MEDIA_SOS; 1065 dev->addr_len = 1; 1066 dev->tx_queue_len = SSIP_TXQUEUE_LEN; 1067 1068 dev->needs_free_netdev = true; 1069 dev->header_ops = &phonet_header_ops; 1070} 1071 1072static int ssi_protocol_probe(struct device *dev) 1073{ 1074 static const char ifname[] = "phonet%d"; 1075 struct hsi_client *cl = to_hsi_client(dev); 1076 struct ssi_protocol *ssi; 1077 int err; 1078 1079 ssi = kzalloc(sizeof(*ssi), GFP_KERNEL); 1080 if (!ssi) 1081 return -ENOMEM; 1082 1083 spin_lock_init(&ssi->lock); 1084 timer_setup(&ssi->rx_wd, ssip_rx_wd, TIMER_DEFERRABLE); 1085 timer_setup(&ssi->tx_wd, ssip_tx_wd, TIMER_DEFERRABLE); 1086 timer_setup(&ssi->keep_alive, ssip_keep_alive, 0); 1087 INIT_LIST_HEAD(&ssi->txqueue); 1088 INIT_LIST_HEAD(&ssi->cmdqueue); 1089 atomic_set(&ssi->tx_usecnt, 0); 1090 hsi_client_set_drvdata(cl, ssi); 1091 ssi->cl = cl; 1092 INIT_WORK(&ssi->work, ssip_xmit_work); 1093 1094 ssi->channel_id_cmd = hsi_get_channel_id_by_name(cl, "mcsaab-control"); 1095 if (ssi->channel_id_cmd < 0) { 1096 err = ssi->channel_id_cmd; 1097 dev_err(dev, "Could not get cmd channel (%d)\n", err); 1098 goto out; 1099 } 1100 1101 ssi->channel_id_data = hsi_get_channel_id_by_name(cl, "mcsaab-data"); 1102 if (ssi->channel_id_data < 0) { 1103 err = ssi->channel_id_data; 1104 dev_err(dev, "Could not get data channel (%d)\n", err); 1105 goto out; 1106 } 1107 1108 err = ssip_alloc_cmds(ssi); 1109 if (err < 0) { 1110 dev_err(dev, "No memory for commands\n"); 1111 goto out; 1112 } 1113 1114 ssi->netdev = alloc_netdev(0, ifname, NET_NAME_UNKNOWN, ssip_pn_setup); 1115 if (!ssi->netdev) { 1116 dev_err(dev, "No memory for netdev\n"); 1117 err = -ENOMEM; 1118 goto out1; 1119 } 1120 1121 /* MTU range: 6 - 65535 */ 1122 ssi->netdev->min_mtu = PHONET_MIN_MTU; 1123 ssi->netdev->max_mtu = SSIP_MAX_MTU; 1124 1125 SET_NETDEV_DEV(ssi->netdev, dev); 1126 netif_carrier_off(ssi->netdev); 1127 err = register_netdev(ssi->netdev); 1128 if (err < 0) { 1129 dev_err(dev, "Register netdev failed (%d)\n", err); 1130 goto out2; 1131 } 1132 1133 list_add(&ssi->link, &ssip_list); 1134 1135 dev_dbg(dev, "channel configuration: cmd=%d, data=%d\n", 1136 ssi->channel_id_cmd, ssi->channel_id_data); 1137 1138 return 0; 1139out2: 1140 free_netdev(ssi->netdev); 1141out1: 1142 ssip_free_cmds(ssi); 1143out: 1144 kfree(ssi); 1145 1146 return err; 1147} 1148 1149static int ssi_protocol_remove(struct device *dev) 1150{ 1151 struct hsi_client *cl = to_hsi_client(dev); 1152 struct ssi_protocol *ssi = hsi_client_drvdata(cl); 1153 1154 list_del(&ssi->link); 1155 unregister_netdev(ssi->netdev); 1156 ssip_free_cmds(ssi); 1157 hsi_client_set_drvdata(cl, NULL); 1158 kfree(ssi); 1159 1160 return 0; 1161} 1162 1163static struct hsi_client_driver ssip_driver = { 1164 .driver = { 1165 .name = "ssi-protocol", 1166 .owner = THIS_MODULE, 1167 .probe = ssi_protocol_probe, 1168 .remove = ssi_protocol_remove, 1169 }, 1170}; 1171 1172static int __init ssip_init(void) 1173{ 1174 pr_info("SSI protocol aka McSAAB added\n"); 1175 1176 return hsi_register_client_driver(&ssip_driver); 1177} 1178module_init(ssip_init); 1179 1180static void __exit ssip_exit(void) 1181{ 1182 hsi_unregister_client_driver(&ssip_driver); 1183 pr_info("SSI protocol driver removed\n"); 1184} 1185module_exit(ssip_exit); 1186 1187MODULE_ALIAS("hsi:ssi-protocol"); 1188MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>"); 1189MODULE_AUTHOR("Remi Denis-Courmont <remi.denis-courmont@nokia.com>"); 1190MODULE_DESCRIPTION("SSI protocol improved aka McSAAB"); 1191MODULE_LICENSE("GPL"); 1192