drivers/hid/intel-ish-hid/ishtp/client.c

   1 /*
   2  * ISHTP client logic
   3  *
   4  * Copyright (c) 2003-2016, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/slab.h>
  18 #include <linux/sched.h>
  19 #include <linux/wait.h>
  20 #include <linux/delay.h>
  21 #include <linux/dma-mapping.h>
  22 #include "hbm.h"
  23 #include "client.h"
  24
  25 /**
  26  * ishtp_read_list_flush() - Flush read queue
  27  * @cl: ishtp client instance
  28  *
  29  * Used to remove all entries from read queue for a client
  30  */
  31 static void ishtp_read_list_flush(struct ishtp_cl *cl)
  32 {
  33         struct ishtp_cl_rb *rb;
  34         struct ishtp_cl_rb *next;
  35         unsigned long   flags;
  36
  37         spin_lock_irqsave(&cl->dev->read_list_spinlock, flags);
  38         list_for_each_entry_safe(rb, next, &cl->dev->read_list.list, list)
  39                 if (rb->cl && ishtp_cl_cmp_id(cl, rb->cl)) {
  40                         list_del(&rb->list);
  41                         ishtp_io_rb_free(rb);
  42                 }
  43         spin_unlock_irqrestore(&cl->dev->read_list_spinlock, flags);
  44 }
  45
  46 /**
  47  * ishtp_cl_flush_queues() - Flush all queues for a client
  48  * @cl: ishtp client instance
  49  *
  50  * Used to remove all queues for a client. This is called when a client device
  51  * needs reset due to error, S3 resume or during module removal
  52  *
  53  * Return: 0 on success else -EINVAL if device is NULL
  54  */
  55 int ishtp_cl_flush_queues(struct ishtp_cl *cl)
  56 {
  57         if (WARN_ON(!cl || !cl->dev))
  58                 return -EINVAL;
  59
  60         ishtp_read_list_flush(cl);
  61
  62         return 0;
  63 }
  64 EXPORT_SYMBOL(ishtp_cl_flush_queues);
  65
  66 /**
  67  * ishtp_cl_init() - Initialize all fields of a client device
  68  * @cl: ishtp client instance
  69  * @dev: ishtp device
  70  *
  71  * Initializes a client device fields: Init spinlocks, init queues etc.
  72  * This function is called during new client creation
  73  */
  74 static void ishtp_cl_init(struct ishtp_cl *cl, struct ishtp_device *dev)
  75 {
  76         memset(cl, 0, sizeof(struct ishtp_cl));
  77         init_waitqueue_head(&cl->wait_ctrl_res);
  78         spin_lock_init(&cl->free_list_spinlock);
  79         spin_lock_init(&cl->in_process_spinlock);
  80         spin_lock_init(&cl->tx_list_spinlock);
  81         spin_lock_init(&cl->tx_free_list_spinlock);
  82         spin_lock_init(&cl->fc_spinlock);
  83         INIT_LIST_HEAD(&cl->link);
  84         cl->dev = dev;
  85
  86         INIT_LIST_HEAD(&cl->free_rb_list.list);
  87         INIT_LIST_HEAD(&cl->tx_list.list);
  88         INIT_LIST_HEAD(&cl->tx_free_list.list);
  89         INIT_LIST_HEAD(&cl->in_process_list.list);
  90
  91         cl->rx_ring_size = CL_DEF_RX_RING_SIZE;
  92         cl->tx_ring_size = CL_DEF_TX_RING_SIZE;
  93
  94         /* dma */
  95         cl->last_tx_path = CL_TX_PATH_IPC;
  96         cl->last_dma_acked = 1;
  97         cl->last_dma_addr = NULL;
  98         cl->last_ipc_acked = 1;
  99 }
 100
 101 /**
 102  * ishtp_cl_allocate() - allocates client structure and sets it up.
 103  * @dev: ishtp device
 104  *
 105  * Allocate memory for new client device and call to initialize each field.
 106  *
 107  * Return: The allocated client instance or NULL on failure
 108  */
 109 struct ishtp_cl *ishtp_cl_allocate(struct ishtp_device *dev)
 110 {
 111         struct ishtp_cl *cl;
 112
 113         cl = kmalloc(sizeof(struct ishtp_cl), GFP_KERNEL);
 114         if (!cl)
 115                 return NULL;
 116
 117         ishtp_cl_init(cl, dev);
 118         return cl;
 119 }
 120 EXPORT_SYMBOL(ishtp_cl_allocate);
 121
 122 /**
 123  * ishtp_cl_free() - Frees a client device
 124  * @cl: client device instance
 125  *
 126  * Frees a client device
 127  */
 128 void    ishtp_cl_free(struct ishtp_cl *cl)
 129 {
 130         struct ishtp_device *dev;
 131         unsigned long flags;
 132
 133         if (!cl)
 134                 return;
 135
 136         dev = cl->dev;
 137         if (!dev)
 138                 return;
 139
 140         spin_lock_irqsave(&dev->cl_list_lock, flags);
 141         ishtp_cl_free_rx_ring(cl);
 142         ishtp_cl_free_tx_ring(cl);
 143         kfree(cl);
 144         spin_unlock_irqrestore(&dev->cl_list_lock, flags);
 145 }
 146 EXPORT_SYMBOL(ishtp_cl_free);
 147
 148 /**
 149  * ishtp_cl_link() - Reserve a host id and link the client instance
 150  * @cl: client device instance
 151  * @id: host client id to use. It can be ISHTP_HOST_CLIENT_ID_ANY if any
 152  *      id from the available can be used
 153  *
 154  *
 155  * This allocates a single bit in the hostmap. This function will make sure
 156  * that not many client sessions are opened at the same time. Once allocated
 157  * the client device instance is added to the ishtp device in the current
 158  * client list
 159  *
 160  * Return: 0 or error code on failure
 161  */
 162 int ishtp_cl_link(struct ishtp_cl *cl, int id)
 163 {
 164         struct ishtp_device *dev;
 165         unsigned long   flags, flags_cl;
 166         int     ret = 0;
 167
 168         if (WARN_ON(!cl || !cl->dev))
 169                 return -EINVAL;
 170
 171         dev = cl->dev;
 172
 173         spin_lock_irqsave(&dev->device_lock, flags);
 174
 175         if (dev->open_handle_count >= ISHTP_MAX_OPEN_HANDLE_COUNT) {
 176                 ret = -EMFILE;
 177                 goto unlock_dev;
 178         }
 179
 180         /* If Id is not assigned get one*/
 181         if (id == ISHTP_HOST_CLIENT_ID_ANY)
 182                 id = find_first_zero_bit(dev->host_clients_map,
 183                         ISHTP_CLIENTS_MAX);
 184
 185         if (id >= ISHTP_CLIENTS_MAX) {
 186                 spin_unlock_irqrestore(&dev->device_lock, flags);
 187                 dev_err(&cl->device->dev, "id exceeded %d", ISHTP_CLIENTS_MAX);
 188                 return -ENOENT;
 189         }
 190
 191         dev->open_handle_count++;
 192         cl->host_client_id = id;
 193         spin_lock_irqsave(&dev->cl_list_lock, flags_cl);
 194         if (dev->dev_state != ISHTP_DEV_ENABLED) {
 195                 ret = -ENODEV;
 196                 goto unlock_cl;
 197         }
 198         list_add_tail(&cl->link, &dev->cl_list);
 199         set_bit(id, dev->host_clients_map);
 200         cl->state = ISHTP_CL_INITIALIZING;
 201
 202 unlock_cl:
 203         spin_unlock_irqrestore(&dev->cl_list_lock, flags_cl);
 204 unlock_dev:
 205         spin_unlock_irqrestore(&dev->device_lock, flags);
 206         return ret;
 207 }
 208 EXPORT_SYMBOL(ishtp_cl_link);
 209
 210 /**
 211  * ishtp_cl_unlink() - remove fw_cl from the client device list
 212  * @cl: client device instance
 213  *
 214  * Remove a previously linked device to a ishtp device
 215  */
 216 void ishtp_cl_unlink(struct ishtp_cl *cl)
 217 {
 218         struct ishtp_device *dev;
 219         struct ishtp_cl *pos;
 220         unsigned long   flags;
 221
 222         /* don't shout on error exit path */
 223         if (!cl || !cl->dev)
 224                 return;
 225
 226         dev = cl->dev;
 227
 228         spin_lock_irqsave(&dev->device_lock, flags);
 229         if (dev->open_handle_count > 0) {
 230                 clear_bit(cl->host_client_id, dev->host_clients_map);
 231                 dev->open_handle_count--;
 232         }
 233         spin_unlock_irqrestore(&dev->device_lock, flags);
 234
 235         /*
 236          * This checks that 'cl' is actually linked into device's structure,
 237          * before attempting 'list_del'
 238          */
 239         spin_lock_irqsave(&dev->cl_list_lock, flags);
 240         list_for_each_entry(pos, &dev->cl_list, link)
 241                 if (cl->host_client_id == pos->host_client_id) {
 242                         list_del_init(&pos->link);
 243                         break;
 244                 }
 245         spin_unlock_irqrestore(&dev->cl_list_lock, flags);
 246 }
 247 EXPORT_SYMBOL(ishtp_cl_unlink);
 248
 249 /**
 250  * ishtp_cl_disconnect() - Send disconnect request to firmware
 251  * @cl: client device instance
 252  *
 253  * Send a disconnect request for a client to firmware.
 254  *
 255  * Return: 0 if successful disconnect response from the firmware or error
 256  * code on failure
 257  */
 258 int ishtp_cl_disconnect(struct ishtp_cl *cl)
 259 {
 260         struct ishtp_device *dev;
 261         int err;
 262
 263         if (WARN_ON(!cl || !cl->dev))
 264                 return -ENODEV;
 265
 266         dev = cl->dev;
 267
 268         dev->print_log(dev, "%s() state %d\n", __func__, cl->state);
 269
 270         if (cl->state != ISHTP_CL_DISCONNECTING) {
 271                 dev->print_log(dev, "%s() Disconnect in progress\n", __func__);
 272                 return 0;
 273         }
 274
 275         if (ishtp_hbm_cl_disconnect_req(dev, cl)) {
 276                 dev->print_log(dev, "%s() Failed to disconnect\n", __func__);
 277                 dev_err(&cl->device->dev, "failed to disconnect.\n");
 278                 return -ENODEV;
 279         }
 280
 281         err = wait_event_interruptible_timeout(cl->wait_ctrl_res,
 282                         (dev->dev_state != ISHTP_DEV_ENABLED ||
 283                         cl->state == ISHTP_CL_DISCONNECTED),
 284                         ishtp_secs_to_jiffies(ISHTP_CL_CONNECT_TIMEOUT));
 285
 286         /*
 287          * If FW reset arrived, this will happen. Don't check cl->,
 288          * as 'cl' may be freed already
 289          */
 290         if (dev->dev_state != ISHTP_DEV_ENABLED) {
 291                 dev->print_log(dev, "%s() dev_state != ISHTP_DEV_ENABLED\n",
 292                                __func__);
 293                 return -ENODEV;
 294         }
 295
 296         if (cl->state == ISHTP_CL_DISCONNECTED) {
 297                 dev->print_log(dev, "%s() successful\n", __func__);
 298                 return 0;
 299         }
 300
 301         return -ENODEV;
 302 }
 303 EXPORT_SYMBOL(ishtp_cl_disconnect);
 304
 305 /**
 306  * ishtp_cl_is_other_connecting() - Check other client is connecting
 307  * @cl: client device instance
 308  *
 309  * Checks if other client with the same fw client id is connecting
 310  *
 311  * Return: true if other client is connected else false
 312  */
 313 static bool ishtp_cl_is_other_connecting(struct ishtp_cl *cl)
 314 {
 315         struct ishtp_device *dev;
 316         struct ishtp_cl *pos;
 317         unsigned long   flags;
 318
 319         if (WARN_ON(!cl || !cl->dev))
 320                 return false;
 321
 322         dev = cl->dev;
 323         spin_lock_irqsave(&dev->cl_list_lock, flags);
 324         list_for_each_entry(pos, &dev->cl_list, link) {
 325                 if ((pos->state == ISHTP_CL_CONNECTING) && (pos != cl) &&
 326                                 cl->fw_client_id == pos->fw_client_id) {
 327                         spin_unlock_irqrestore(&dev->cl_list_lock, flags);
 328                         return true;
 329                 }
 330         }
 331         spin_unlock_irqrestore(&dev->cl_list_lock, flags);
 332
 333         return false;
 334 }
 335
 336 /**
 337  * ishtp_cl_connect() - Send connect request to firmware
 338  * @cl: client device instance
 339  *
 340  * Send a connect request for a client to firmware. If successful it will
 341  * RX and TX ring buffers
 342  *
 343  * Return: 0 if successful connect response from the firmware and able
 344  * to bind and allocate ring buffers or error code on failure
 345  */
 346 int ishtp_cl_connect(struct ishtp_cl *cl)
 347 {
 348         struct ishtp_device *dev;
 349         int rets;
 350
 351         if (WARN_ON(!cl || !cl->dev))
 352                 return -ENODEV;
 353
 354         dev = cl->dev;
 355
 356         dev->print_log(dev, "%s() current_state = %d\n", __func__, cl->state);
 357
 358         if (ishtp_cl_is_other_connecting(cl)) {
 359                 dev->print_log(dev, "%s() Busy\n", __func__);
 360                 return  -EBUSY;
 361         }
 362
 363         if (ishtp_hbm_cl_connect_req(dev, cl)) {
 364                 dev->print_log(dev, "%s() HBM connect req fail\n", __func__);
 365                 return -ENODEV;
 366         }
 367
 368         rets = wait_event_interruptible_timeout(cl->wait_ctrl_res,
 369                                 (dev->dev_state == ISHTP_DEV_ENABLED &&
 370                                 (cl->state == ISHTP_CL_CONNECTED ||
 371                                  cl->state == ISHTP_CL_DISCONNECTED)),
 372                                 ishtp_secs_to_jiffies(
 373                                         ISHTP_CL_CONNECT_TIMEOUT));
 374         /*
 375          * If FW reset arrived, this will happen. Don't check cl->,
 376          * as 'cl' may be freed already
 377          */
 378         if (dev->dev_state != ISHTP_DEV_ENABLED) {
 379                 dev->print_log(dev, "%s() dev_state != ISHTP_DEV_ENABLED\n",
 380                                __func__);
 381                 return -EFAULT;
 382         }
 383
 384         if (cl->state != ISHTP_CL_CONNECTED) {
 385                 dev->print_log(dev, "%s() state != ISHTP_CL_CONNECTED\n",
 386                                __func__);
 387                 return -EFAULT;
 388         }
 389
 390         rets = cl->status;
 391         if (rets) {
 392                 dev->print_log(dev, "%s() Invalid status\n", __func__);
 393                 return rets;
 394         }
 395
 396         rets = ishtp_cl_device_bind(cl);
 397         if (rets) {
 398                 dev->print_log(dev, "%s() Bind error\n", __func__);
 399                 ishtp_cl_disconnect(cl);
 400                 return rets;
 401         }
 402
 403         rets = ishtp_cl_alloc_rx_ring(cl);
 404         if (rets) {
 405                 dev->print_log(dev, "%s() Alloc RX ring failed\n", __func__);
 406                 /* if failed allocation, disconnect */
 407                 ishtp_cl_disconnect(cl);
 408                 return rets;
 409         }
 410
 411         rets = ishtp_cl_alloc_tx_ring(cl);
 412         if (rets) {
 413                 dev->print_log(dev, "%s() Alloc TX ring failed\n", __func__);
 414                 /* if failed allocation, disconnect */
 415                 ishtp_cl_free_rx_ring(cl);
 416                 ishtp_cl_disconnect(cl);
 417                 return rets;
 418         }
 419
 420         /* Upon successful connection and allocation, emit flow-control */
 421         rets = ishtp_cl_read_start(cl);
 422
 423         dev->print_log(dev, "%s() successful\n", __func__);
 424
 425         return rets;
 426 }
 427 EXPORT_SYMBOL(ishtp_cl_connect);
 428
 429 /**
 430  * ishtp_cl_read_start() - Prepare to read client message
 431  * @cl: client device instance
 432  *
 433  * Get a free buffer from pool of free read buffers and add to read buffer
 434  * pool to add contents. Send a flow control request to firmware to be able
 435  * send next message.
 436  *
 437  * Return: 0 if successful or error code on failure
 438  */
 439 int ishtp_cl_read_start(struct ishtp_cl *cl)
 440 {
 441         struct ishtp_device *dev;
 442         struct ishtp_cl_rb *rb;
 443         int rets;
 444         int i;
 445         unsigned long   flags;
 446         unsigned long   dev_flags;
 447
 448         if (WARN_ON(!cl || !cl->dev))
 449                 return -ENODEV;
 450
 451         dev = cl->dev;
 452
 453         if (cl->state != ISHTP_CL_CONNECTED)
 454                 return -ENODEV;
 455
 456         if (dev->dev_state != ISHTP_DEV_ENABLED)
 457                 return -ENODEV;
 458
 459         i = ishtp_fw_cl_by_id(dev, cl->fw_client_id);
 460         if (i < 0) {
 461                 dev_err(&cl->device->dev, "no such fw client %d\n",
 462                         cl->fw_client_id);
 463                 return -ENODEV;
 464         }
 465
 466         /* The current rb is the head of the free rb list */
 467         spin_lock_irqsave(&cl->free_list_spinlock, flags);
 468         if (list_empty(&cl->free_rb_list.list)) {
 469                 dev_warn(&cl->device->dev,
 470                          "[ishtp-ish] Rx buffers pool is empty\n");
 471                 rets = -ENOMEM;
 472                 rb = NULL;
 473                 spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
 474                 goto out;
 475         }
 476         rb = list_entry(cl->free_rb_list.list.next, struct ishtp_cl_rb, list);
 477         list_del_init(&rb->list);
 478         spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
 479
 480         rb->cl = cl;
 481         rb->buf_idx = 0;
 482
 483         INIT_LIST_HEAD(&rb->list);
 484         rets = 0;
 485
 486         /*
 487          * This must be BEFORE sending flow control -
 488          * response in ISR may come too fast...
 489          */
 490         spin_lock_irqsave(&dev->read_list_spinlock, dev_flags);
 491         list_add_tail(&rb->list, &dev->read_list.list);
 492         spin_unlock_irqrestore(&dev->read_list_spinlock, dev_flags);
 493         if (ishtp_hbm_cl_flow_control_req(dev, cl)) {
 494                 rets = -ENODEV;
 495                 goto out;
 496         }
 497 out:
 498         /* if ishtp_hbm_cl_flow_control_req failed, return rb to free list */
 499         if (rets && rb) {
 500                 spin_lock_irqsave(&dev->read_list_spinlock, dev_flags);
 501                 list_del(&rb->list);
 502                 spin_unlock_irqrestore(&dev->read_list_spinlock, dev_flags);
 503
 504                 spin_lock_irqsave(&cl->free_list_spinlock, flags);
 505                 list_add_tail(&rb->list, &cl->free_rb_list.list);
 506                 spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
 507         }
 508         return rets;
 509 }
 510
 511 /**
 512  * ishtp_cl_send() - Send a message to firmware
 513  * @cl: client device instance
 514  * @buf: message buffer
 515  * @length: length of message
 516  *
 517  * If the client is correct state to send message, this function gets a buffer
 518  * from tx ring buffers, copy the message data and call to send the message
 519  * using ishtp_cl_send_msg()
 520  *
 521  * Return: 0 if successful or error code on failure
 522  */
 523 int ishtp_cl_send(struct ishtp_cl *cl, uint8_t *buf, size_t length)
 524 {
 525         struct ishtp_device     *dev;
 526         int     id;
 527         struct ishtp_cl_tx_ring *cl_msg;
 528         int     have_msg_to_send = 0;
 529         unsigned long   tx_flags, tx_free_flags;
 530
 531         if (WARN_ON(!cl || !cl->dev))
 532                 return -ENODEV;
 533
 534         dev = cl->dev;
 535
 536         if (cl->state != ISHTP_CL_CONNECTED) {
 537                 ++cl->err_send_msg;
 538                 return -EPIPE;
 539         }
 540
 541         if (dev->dev_state != ISHTP_DEV_ENABLED) {
 542                 ++cl->err_send_msg;
 543                 return -ENODEV;
 544         }
 545
 546         /* Check if we have fw client device */
 547         id = ishtp_fw_cl_by_id(dev, cl->fw_client_id);
 548         if (id < 0) {
 549                 ++cl->err_send_msg;
 550                 return -ENOENT;
 551         }
 552
 553         if (length > dev->fw_clients[id].props.max_msg_length) {
 554                 ++cl->err_send_msg;
 555                 return -EMSGSIZE;
 556         }
 557
 558         /* No free bufs */
 559         spin_lock_irqsave(&cl->tx_free_list_spinlock, tx_free_flags);
 560         if (list_empty(&cl->tx_free_list.list)) {
 561                 spin_unlock_irqrestore(&cl->tx_free_list_spinlock,
 562                         tx_free_flags);
 563                 ++cl->err_send_msg;
 564                 return  -ENOMEM;
 565         }
 566
 567         cl_msg = list_first_entry(&cl->tx_free_list.list,
 568                 struct ishtp_cl_tx_ring, list);
 569         if (!cl_msg->send_buf.data) {
 570                 spin_unlock_irqrestore(&cl->tx_free_list_spinlock,
 571                         tx_free_flags);
 572                 return  -EIO;
 573                 /* Should not happen, as free list is pre-allocated */
 574         }
 575         /*
 576          * This is safe, as 'length' is already checked for not exceeding
 577          * max ISHTP message size per client
 578          */
 579         list_del_init(&cl_msg->list);
 580         spin_unlock_irqrestore(&cl->tx_free_list_spinlock, tx_free_flags);
 581         memcpy(cl_msg->send_buf.data, buf, length);
 582         cl_msg->send_buf.size = length;
 583         spin_lock_irqsave(&cl->tx_list_spinlock, tx_flags);
 584         have_msg_to_send = !list_empty(&cl->tx_list.list);
 585         list_add_tail(&cl_msg->list, &cl->tx_list.list);
 586         spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 587
 588         if (!have_msg_to_send && cl->ishtp_flow_ctrl_creds > 0)
 589                 ishtp_cl_send_msg(dev, cl);
 590
 591         return  0;
 592 }
 593 EXPORT_SYMBOL(ishtp_cl_send);
 594
 595 /**
 596  * ishtp_cl_read_complete() - read complete
 597  * @rb: Pointer to client request block
 598  *
 599  * If the message is completely received call ishtp_cl_bus_rx_event()
 600  * to process message
 601  */
 602 static void ishtp_cl_read_complete(struct ishtp_cl_rb *rb)
 603 {
 604         unsigned long   flags;
 605         int     schedule_work_flag = 0;
 606         struct ishtp_cl *cl = rb->cl;
 607
 608         spin_lock_irqsave(&cl->in_process_spinlock, flags);
 609         /*
 610          * if in-process list is empty, then need to schedule
 611          * the processing thread
 612          */
 613         schedule_work_flag = list_empty(&cl->in_process_list.list);
 614         list_add_tail(&rb->list, &cl->in_process_list.list);
 615         spin_unlock_irqrestore(&cl->in_process_spinlock, flags);
 616
 617         if (schedule_work_flag)
 618                 ishtp_cl_bus_rx_event(cl->device);
 619 }
 620
 621 /**
 622  * ipc_tx_callback() - IPC tx callback function
 623  * @prm: Pointer to client device instance
 624  *
 625  * Send message over IPC either first time or on callback on previous message
 626  * completion
 627  */
 628 static void ipc_tx_callback(void *prm)
 629 {
 630         struct ishtp_cl *cl = prm;
 631         struct ishtp_cl_tx_ring *cl_msg;
 632         size_t  rem;
 633         struct ishtp_device     *dev = (cl ? cl->dev : NULL);
 634         struct ishtp_msg_hdr    ishtp_hdr;
 635         unsigned long   tx_flags, tx_free_flags;
 636         unsigned char   *pmsg;
 637
 638         if (!dev)
 639                 return;
 640
 641         /*
 642          * Other conditions if some critical error has
 643          * occurred before this callback is called
 644          */
 645         if (dev->dev_state != ISHTP_DEV_ENABLED)
 646                 return;
 647
 648         if (cl->state != ISHTP_CL_CONNECTED)
 649                 return;
 650
 651         spin_lock_irqsave(&cl->tx_list_spinlock, tx_flags);
 652         if (list_empty(&cl->tx_list.list)) {
 653                 spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 654                 return;
 655         }
 656
 657         if (cl->ishtp_flow_ctrl_creds != 1 && !cl->sending) {
 658                 spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 659                 return;
 660         }
 661
 662         if (!cl->sending) {
 663                 --cl->ishtp_flow_ctrl_creds;
 664                 cl->last_ipc_acked = 0;
 665                 cl->last_tx_path = CL_TX_PATH_IPC;
 666                 cl->sending = 1;
 667         }
 668
 669         cl_msg = list_entry(cl->tx_list.list.next, struct ishtp_cl_tx_ring,
 670                             list);
 671         rem = cl_msg->send_buf.size - cl->tx_offs;
 672
 673         ishtp_hdr.host_addr = cl->host_client_id;
 674         ishtp_hdr.fw_addr = cl->fw_client_id;
 675         ishtp_hdr.reserved = 0;
 676         pmsg = cl_msg->send_buf.data + cl->tx_offs;
 677
 678         if (rem <= dev->mtu) {
 679                 ishtp_hdr.length = rem;
 680                 ishtp_hdr.msg_complete = 1;
 681                 cl->sending = 0;
 682                 list_del_init(&cl_msg->list);   /* Must be before write */
 683                 spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 684                 /* Submit to IPC queue with no callback */
 685                 ishtp_write_message(dev, &ishtp_hdr, pmsg);
 686                 spin_lock_irqsave(&cl->tx_free_list_spinlock, tx_free_flags);
 687                 list_add_tail(&cl_msg->list, &cl->tx_free_list.list);
 688                 spin_unlock_irqrestore(&cl->tx_free_list_spinlock,
 689                         tx_free_flags);
 690         } else {
 691                 /* Send IPC fragment */
 692                 spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 693                 cl->tx_offs += dev->mtu;
 694                 ishtp_hdr.length = dev->mtu;
 695                 ishtp_hdr.msg_complete = 0;
 696                 ishtp_send_msg(dev, &ishtp_hdr, pmsg, ipc_tx_callback, cl);
 697         }
 698 }
 699
 700 /**
 701  * ishtp_cl_send_msg_ipc() -Send message using IPC
 702  * @dev: ISHTP device instance
 703  * @cl: Pointer to client device instance
 704  *
 705  * Send message over IPC not using DMA
 706  */
 707 static void ishtp_cl_send_msg_ipc(struct ishtp_device *dev,
 708                                   struct ishtp_cl *cl)
 709 {
 710         /* If last DMA message wasn't acked yet, leave this one in Tx queue */
 711         if (cl->last_tx_path == CL_TX_PATH_DMA && cl->last_dma_acked == 0)
 712                 return;
 713
 714         cl->tx_offs = 0;
 715         ipc_tx_callback(cl);
 716         ++cl->send_msg_cnt_ipc;
 717 }
 718
 719 /**
 720  * ishtp_cl_send_msg_dma() -Send message using DMA
 721  * @dev: ISHTP device instance
 722  * @cl: Pointer to client device instance
 723  *
 724  * Send message using DMA
 725  */
 726 static void ishtp_cl_send_msg_dma(struct ishtp_device *dev,
 727         struct ishtp_cl *cl)
 728 {
 729         struct ishtp_msg_hdr    hdr;
 730         struct dma_xfer_hbm     dma_xfer;
 731         unsigned char   *msg_addr;
 732         int off;
 733         struct ishtp_cl_tx_ring *cl_msg;
 734         unsigned long tx_flags, tx_free_flags;
 735
 736         /* If last IPC message wasn't acked yet, leave this one in Tx queue */
 737         if (cl->last_tx_path == CL_TX_PATH_IPC && cl->last_ipc_acked == 0)
 738                 return;
 739
 740         spin_lock_irqsave(&cl->tx_list_spinlock, tx_flags);
 741         if (list_empty(&cl->tx_list.list)) {
 742                 spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 743                 return;
 744         }
 745
 746         cl_msg = list_entry(cl->tx_list.list.next, struct ishtp_cl_tx_ring,
 747                 list);
 748
 749         msg_addr = ishtp_cl_get_dma_send_buf(dev, cl_msg->send_buf.size);
 750         if (!msg_addr) {
 751                 spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 752                 if (dev->transfer_path == CL_TX_PATH_DEFAULT)
 753                         ishtp_cl_send_msg_ipc(dev, cl);
 754                 return;
 755         }
 756
 757         list_del_init(&cl_msg->list);   /* Must be before write */
 758         spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
 759
 760         --cl->ishtp_flow_ctrl_creds;
 761         cl->last_dma_acked = 0;
 762         cl->last_dma_addr = msg_addr;
 763         cl->last_tx_path = CL_TX_PATH_DMA;
 764
 765         /* write msg to dma buf */
 766         memcpy(msg_addr, cl_msg->send_buf.data, cl_msg->send_buf.size);
 767
 768         /* send dma_xfer hbm msg */
 769         off = msg_addr - (unsigned char *)dev->ishtp_host_dma_tx_buf;
 770         ishtp_hbm_hdr(&hdr, sizeof(struct dma_xfer_hbm));
 771         dma_xfer.hbm = DMA_XFER;
 772         dma_xfer.fw_client_id = cl->fw_client_id;
 773         dma_xfer.host_client_id = cl->host_client_id;
 774         dma_xfer.reserved = 0;
 775         dma_xfer.msg_addr = dev->ishtp_host_dma_tx_buf_phys + off;
 776         dma_xfer.msg_length = cl_msg->send_buf.size;
 777         dma_xfer.reserved2 = 0;
 778         ishtp_write_message(dev, &hdr, (unsigned char *)&dma_xfer);
 779         spin_lock_irqsave(&cl->tx_free_list_spinlock, tx_free_flags);
 780         list_add_tail(&cl_msg->list, &cl->tx_free_list.list);
 781         spin_unlock_irqrestore(&cl->tx_free_list_spinlock, tx_free_flags);
 782         ++cl->send_msg_cnt_dma;
 783 }
 784
 785 /**
 786  * ishtp_cl_send_msg() -Send message using DMA or IPC
 787  * @dev: ISHTP device instance
 788  * @cl: Pointer to client device instance
 789  *
 790  * Send message using DMA or IPC based on transfer_path
 791  */
 792 void ishtp_cl_send_msg(struct ishtp_device *dev, struct ishtp_cl *cl)
 793 {
 794         if (dev->transfer_path == CL_TX_PATH_DMA)
 795                 ishtp_cl_send_msg_dma(dev, cl);
 796         else
 797                 ishtp_cl_send_msg_ipc(dev, cl);
 798 }
 799
 800 /**
 801  * recv_ishtp_cl_msg() -Receive client message
 802  * @dev: ISHTP device instance
 803  * @ishtp_hdr: Pointer to message header
 804  *
 805  * Receive and dispatch ISHTP client messages. This function executes in ISR
 806  * context
 807  */
 808 void recv_ishtp_cl_msg(struct ishtp_device *dev,
 809                        struct ishtp_msg_hdr *ishtp_hdr)
 810 {
 811         struct ishtp_cl *cl;
 812         struct ishtp_cl_rb *rb;
 813         struct ishtp_cl_rb *new_rb;
 814         unsigned char *buffer = NULL;
 815         struct ishtp_cl_rb *complete_rb = NULL;
 816         unsigned long   dev_flags;
 817         unsigned long   flags;
 818         int     rb_count;
 819
 820         if (ishtp_hdr->reserved) {
 821                 dev_err(dev->devc, "corrupted message header.\n");
 822                 goto    eoi;
 823         }
 824
 825         if (ishtp_hdr->length > IPC_PAYLOAD_SIZE) {
 826                 dev_err(dev->devc,
 827                         "ISHTP message length in hdr exceeds IPC MTU\n");
 828                 goto    eoi;
 829         }
 830
 831         spin_lock_irqsave(&dev->read_list_spinlock, dev_flags);
 832         rb_count = -1;
 833         list_for_each_entry(rb, &dev->read_list.list, list) {
 834                 ++rb_count;
 835                 cl = rb->cl;
 836                 if (!cl || !(cl->host_client_id == ishtp_hdr->host_addr &&
 837                                 cl->fw_client_id == ishtp_hdr->fw_addr) ||
 838                                 !(cl->state == ISHTP_CL_CONNECTED))
 839                         continue;
 840
 841                  /* If no Rx buffer is allocated, disband the rb */
 842                 if (rb->buffer.size == 0 || rb->buffer.data == NULL) {
 843                         spin_unlock_irqrestore(&dev->read_list_spinlock,
 844                                 dev_flags);
 845                         dev_err(&cl->device->dev,
 846                                 "Rx buffer is not allocated.\n");
 847                         list_del(&rb->list);
 848                         ishtp_io_rb_free(rb);
 849                         cl->status = -ENOMEM;
 850                         goto    eoi;
 851                 }
 852
 853                 /*
 854                  * If message buffer overflown (exceeds max. client msg
 855                  * size, drop message and return to free buffer.
 856                  * Do we need to disconnect such a client? (We don't send
 857                  * back FC, so communication will be stuck anyway)
 858                  */
 859                 if (rb->buffer.size < ishtp_hdr->length + rb->buf_idx) {
 860                         spin_unlock_irqrestore(&dev->read_list_spinlock,
 861                                 dev_flags);
 862                         dev_err(&cl->device->dev,
 863                                 "message overflow. size %d len %d idx %ld\n",
 864                                 rb->buffer.size, ishtp_hdr->length,
 865                                 rb->buf_idx);
 866                         list_del(&rb->list);
 867                         ishtp_cl_io_rb_recycle(rb);
 868                         cl->status = -EIO;
 869                         goto    eoi;
 870                 }
 871
 872                 buffer = rb->buffer.data + rb->buf_idx;
 873                 dev->ops->ishtp_read(dev, buffer, ishtp_hdr->length);
 874
 875                 rb->buf_idx += ishtp_hdr->length;
 876                 if (ishtp_hdr->msg_complete) {
 877                         /* Last fragment in message - it's complete */
 878                         cl->status = 0;
 879                         list_del(&rb->list);
 880                         complete_rb = rb;
 881
 882                         --cl->out_flow_ctrl_creds;
 883                         /*
 884                          * the whole msg arrived, send a new FC, and add a new
 885                          * rb buffer for the next coming msg
 886                          */
 887                         spin_lock_irqsave(&cl->free_list_spinlock, flags);
 888
 889                         if (!list_empty(&cl->free_rb_list.list)) {
 890                                 new_rb = list_entry(cl->free_rb_list.list.next,
 891                                         struct ishtp_cl_rb, list);
 892                                 list_del_init(&new_rb->list);
 893                                 spin_unlock_irqrestore(&cl->free_list_spinlock,
 894                                         flags);
 895                                 new_rb->cl = cl;
 896                                 new_rb->buf_idx = 0;
 897                                 INIT_LIST_HEAD(&new_rb->list);
 898                                 list_add_tail(&new_rb->list,
 899                                         &dev->read_list.list);
 900
 901                                 ishtp_hbm_cl_flow_control_req(dev, cl);
 902                         } else {
 903                                 spin_unlock_irqrestore(&cl->free_list_spinlock,
 904                                         flags);
 905                         }
 906                 }
 907                 /* One more fragment in message (even if this was last) */
 908                 ++cl->recv_msg_num_frags;
 909
 910                 /*
 911                  * We can safely break here (and in BH too),
 912                  * a single input message can go only to a single request!
 913                  */
 914                 break;
 915         }
 916
 917         spin_unlock_irqrestore(&dev->read_list_spinlock, dev_flags);
 918         /* If it's nobody's message, just read and discard it */
 919         if (!buffer) {
 920                 uint8_t rd_msg_buf[ISHTP_RD_MSG_BUF_SIZE];
 921
 922                 dev_err(dev->devc, "Dropped Rx msg - no request\n");
 923                 dev->ops->ishtp_read(dev, rd_msg_buf, ishtp_hdr->length);
 924                 goto    eoi;
 925         }
 926
 927         if (complete_rb) {
 928                 getnstimeofday(&cl->ts_rx);
 929                 ++cl->recv_msg_cnt_ipc;
 930                 ishtp_cl_read_complete(complete_rb);
 931         }
 932 eoi:
 933         return;
 934 }
 935
 936 /**
 937  * recv_ishtp_cl_msg_dma() -Receive client message
 938  * @dev: ISHTP device instance
 939  * @msg: message pointer
 940  * @hbm: hbm buffer
 941  *
 942  * Receive and dispatch ISHTP client messages using DMA. This function executes
 943  * in ISR context
 944  */
 945 void recv_ishtp_cl_msg_dma(struct ishtp_device *dev, void *msg,
 946                            struct dma_xfer_hbm *hbm)
 947 {
 948         struct ishtp_cl *cl;
 949         struct ishtp_cl_rb *rb;
 950         struct ishtp_cl_rb *new_rb;
 951         unsigned char *buffer = NULL;
 952         struct ishtp_cl_rb *complete_rb = NULL;
 953         unsigned long   dev_flags;
 954         unsigned long   flags;
 955
 956         spin_lock_irqsave(&dev->read_list_spinlock, dev_flags);
 957         list_for_each_entry(rb, &dev->read_list.list, list) {
 958                 cl = rb->cl;
 959                 if (!cl || !(cl->host_client_id == hbm->host_client_id &&
 960                                 cl->fw_client_id == hbm->fw_client_id) ||
 961                                 !(cl->state == ISHTP_CL_CONNECTED))
 962                         continue;
 963
 964                 /*
 965                  * If no Rx buffer is allocated, disband the rb
 966                  */
 967                 if (rb->buffer.size == 0 || rb->buffer.data == NULL) {
 968                         spin_unlock_irqrestore(&dev->read_list_spinlock,
 969                                 dev_flags);
 970                         dev_err(&cl->device->dev,
 971                                 "response buffer is not allocated.\n");
 972                         list_del(&rb->list);
 973                         ishtp_io_rb_free(rb);
 974                         cl->status = -ENOMEM;
 975                         goto    eoi;
 976                 }
 977
 978                 /*
 979                  * If message buffer overflown (exceeds max. client msg
 980                  * size, drop message and return to free buffer.
 981                  * Do we need to disconnect such a client? (We don't send
 982                  * back FC, so communication will be stuck anyway)
 983                  */
 984                 if (rb->buffer.size < hbm->msg_length) {
 985                         spin_unlock_irqrestore(&dev->read_list_spinlock,
 986                                 dev_flags);
 987                         dev_err(&cl->device->dev,
 988                                 "message overflow. size %d len %d idx %ld\n",
 989                                 rb->buffer.size, hbm->msg_length, rb->buf_idx);
 990                         list_del(&rb->list);
 991                         ishtp_cl_io_rb_recycle(rb);
 992                         cl->status = -EIO;
 993                         goto    eoi;
 994                 }
 995
 996                 buffer = rb->buffer.data;
 997                 memcpy(buffer, msg, hbm->msg_length);
 998                 rb->buf_idx = hbm->msg_length;
 999
1000                 /* Last fragment in message - it's complete */
1001                 cl->status = 0;
1002                 list_del(&rb->list);
1003                 complete_rb = rb;
1004
1005                 --cl->out_flow_ctrl_creds;
1006                 /*
1007                  * the whole msg arrived, send a new FC, and add a new
1008                  * rb buffer for the next coming msg
1009                  */
1010                 spin_lock_irqsave(&cl->free_list_spinlock, flags);
1011
1012                 if (!list_empty(&cl->free_rb_list.list)) {
1013                         new_rb = list_entry(cl->free_rb_list.list.next,
1014                                 struct ishtp_cl_rb, list);
1015                         list_del_init(&new_rb->list);
1016                         spin_unlock_irqrestore(&cl->free_list_spinlock,
1017                                 flags);
1018                         new_rb->cl = cl;
1019                         new_rb->buf_idx = 0;
1020                         INIT_LIST_HEAD(&new_rb->list);
1021                         list_add_tail(&new_rb->list,
1022                                 &dev->read_list.list);
1023
1024                         ishtp_hbm_cl_flow_control_req(dev, cl);
1025                 } else {
1026                         spin_unlock_irqrestore(&cl->free_list_spinlock,
1027                                 flags);
1028                 }
1029
1030                 /* One more fragment in message (this is always last) */
1031                 ++cl->recv_msg_num_frags;
1032
1033                 /*
1034                  * We can safely break here (and in BH too),
1035                  * a single input message can go only to a single request!
1036                  */
1037                 break;
1038         }
1039
1040         spin_unlock_irqrestore(&dev->read_list_spinlock, dev_flags);
1041         /* If it's nobody's message, just read and discard it */
1042         if (!buffer) {
1043                 dev_err(dev->devc, "Dropped Rx (DMA) msg - no request\n");
1044                 goto    eoi;
1045         }
1046
1047         if (complete_rb) {
1048                 getnstimeofday(&cl->ts_rx);
1049                 ++cl->recv_msg_cnt_dma;
1050                 ishtp_cl_read_complete(complete_rb);
1051         }
1052 eoi:
1053         return;
1054 }