1 // SPDX-License-Identifier: GPL-2.0 2 // ISHTP interface for ChromeOS Embedded Controller 3 // 4 // Copyright (c) 2019, Intel Corporation. 5 // 6 // ISHTP client driver for talking to the Chrome OS EC firmware running 7 // on Intel Integrated Sensor Hub (ISH) using the ISH Transport protocol 8 // (ISH-TP). 9 10 #include <linux/delay.h> 11 #include <linux/module.h> 12 #include <linux/pci.h> 13 #include <linux/platform_data/cros_ec_commands.h> 14 #include <linux/platform_data/cros_ec_proto.h> 15 #include <linux/intel-ish-client-if.h> 16 17 #include "cros_ec.h" 18 19 /* 20 * ISH TX/RX ring buffer pool size 21 * 22 * The AP->ISH messages and corresponding ISH->AP responses are 23 * serialized. We need 1 TX and 1 RX buffer for these. 24 * 25 * The MKBP ISH->AP events are serialized. We need one additional RX 26 * buffer for them. 27 */ 28 #define CROS_ISH_CL_TX_RING_SIZE 8 29 #define CROS_ISH_CL_RX_RING_SIZE 8 30 31 /* ISH CrOS EC Host Commands */ 32 enum cros_ec_ish_channel { 33 CROS_EC_COMMAND = 1, /* AP->ISH message */ 34 CROS_MKBP_EVENT = 2, /* ISH->AP events */ 35 }; 36 37 /* 38 * ISH firmware timeout for 1 message send failure is 1Hz, and the 39 * firmware will retry 2 times, so 3Hz is used for timeout. 40 */ 41 #define ISHTP_SEND_TIMEOUT (3 * HZ) 42 43 /* ISH Transport CrOS EC ISH client unique GUID */ 44 static const struct ishtp_device_id cros_ec_ishtp_id_table[] = { 45 { .guid = GUID_INIT(0x7b7154d0, 0x56f4, 0x4bdc, 46 0xb0, 0xd8, 0x9e, 0x7c, 0xda, 0xe0, 0xd6, 0xa0), }, 47 { } 48 }; 49 MODULE_DEVICE_TABLE(ishtp, cros_ec_ishtp_id_table); 50 51 struct header { 52 u8 channel; 53 u8 status; 54 u8 token; 55 u8 reserved; 56 } __packed; 57 58 struct cros_ish_out_msg { 59 struct header hdr; 60 struct ec_host_request ec_request; 61 } __packed; 62 63 struct cros_ish_in_msg { 64 struct header hdr; 65 struct ec_host_response ec_response; 66 } __packed; 67 68 #define IN_MSG_EC_RESPONSE_PREAMBLE \ 69 offsetof(struct cros_ish_in_msg, ec_response) 70 71 #define OUT_MSG_EC_REQUEST_PREAMBLE \ 72 offsetof(struct cros_ish_out_msg, ec_request) 73 74 #define cl_data_to_dev(client_data) ishtp_device((client_data)->cl_device) 75 76 /* 77 * The Read-Write Semaphore is used to prevent message TX or RX while 78 * the ishtp client is being initialized or undergoing reset. 79 * 80 * The readers are the kernel function calls responsible for IA->ISH 81 * and ISH->AP messaging. 82 * 83 * The writers are .reset() and .probe() function. 84 */ 85 static DECLARE_RWSEM(init_lock); 86 87 /** 88 * struct response_info - Encapsulate firmware response related 89 * information for passing between function ish_send() and 90 * process_recv() callback. 91 * 92 * @data: Copy the data received from firmware here. 93 * @max_size: Max size allocated for the @data buffer. If the received 94 * data exceeds this value, we log an error. 95 * @size: Actual size of data received from firmware. 96 * @error: 0 for success, negative error code for a failure in process_recv(). 97 * @token: Expected token for response that we are waiting on. 98 * @received: Set to true on receiving a valid firmware response to host command 99 * @wait_queue: Wait queue for host to wait for firmware response. 100 */ 101 struct response_info { 102 void *data; 103 size_t max_size; 104 size_t size; 105 int error; 106 u8 token; 107 bool received; 108 wait_queue_head_t wait_queue; 109 }; 110 111 /** 112 * struct ishtp_cl_data - Encapsulate per ISH TP Client. 113 * 114 * @cros_ish_cl: ISHTP firmware client instance. 115 * @cl_device: ISHTP client device instance. 116 * @response: Response info passing between ish_send() and process_recv(). 117 * @work_ishtp_reset: Work queue reset handling. 118 * @work_ec_evt: Work queue for EC events. 119 * @ec_dev: CrOS EC MFD device. 120 * 121 * This structure is used to store per client data. 122 */ 123 struct ishtp_cl_data { 124 struct ishtp_cl *cros_ish_cl; 125 struct ishtp_cl_device *cl_device; 126 127 /* 128 * Used for passing firmware response information between 129 * ish_send() and process_recv() callback. 130 */ 131 struct response_info response; 132 133 struct work_struct work_ishtp_reset; 134 struct work_struct work_ec_evt; 135 struct cros_ec_device *ec_dev; 136 }; 137 138 /** 139 * ish_evt_handler - ISH to AP event handler 140 * @work: Work struct 141 */ 142 static void ish_evt_handler(struct work_struct *work) 143 { 144 struct ishtp_cl_data *client_data = 145 container_of(work, struct ishtp_cl_data, work_ec_evt); 146 147 cros_ec_irq_thread(0, client_data->ec_dev); 148 } 149 150 /** 151 * ish_send() - Send message from host to firmware 152 * 153 * @client_data: Client data instance 154 * @out_msg: Message buffer to be sent to firmware 155 * @out_size: Size of out going message 156 * @in_msg: Message buffer where the incoming data is copied. This buffer 157 * is allocated by calling 158 * @in_size: Max size of incoming message 159 * 160 * Return: Number of bytes copied in the in_msg on success, negative 161 * error code on failure. 162 */ 163 static int ish_send(struct ishtp_cl_data *client_data, 164 u8 *out_msg, size_t out_size, 165 u8 *in_msg, size_t in_size) 166 { 167 static u8 next_token; 168 int rv; 169 struct header *out_hdr = (struct header *)out_msg; 170 struct ishtp_cl *cros_ish_cl = client_data->cros_ish_cl; 171 172 dev_dbg(cl_data_to_dev(client_data), 173 "%s: channel=%02u status=%02u\n", 174 __func__, out_hdr->channel, out_hdr->status); 175 176 /* Setup for incoming response */ 177 client_data->response.data = in_msg; 178 client_data->response.max_size = in_size; 179 client_data->response.error = 0; 180 client_data->response.token = next_token++; 181 client_data->response.received = false; 182 183 out_hdr->token = client_data->response.token; 184 185 rv = ishtp_cl_send(cros_ish_cl, out_msg, out_size); 186 if (rv) { 187 dev_err(cl_data_to_dev(client_data), 188 "ishtp_cl_send error %d\n", rv); 189 return rv; 190 } 191 192 wait_event_interruptible_timeout(client_data->response.wait_queue, 193 client_data->response.received, 194 ISHTP_SEND_TIMEOUT); 195 if (!client_data->response.received) { 196 dev_err(cl_data_to_dev(client_data), 197 "Timed out for response to host message\n"); 198 return -ETIMEDOUT; 199 } 200 201 if (client_data->response.error < 0) 202 return client_data->response.error; 203 204 return client_data->response.size; 205 } 206 207 /** 208 * process_recv() - Received and parse incoming packet 209 * @cros_ish_cl: Client instance to get stats 210 * @rb_in_proc: Host interface message buffer 211 * @timestamp: Timestamp of when parent callback started 212 * 213 * Parse the incoming packet. If it is a response packet then it will 214 * update per instance flags and wake up the caller waiting to for the 215 * response. If it is an event packet then it will schedule event work. 216 */ 217 static void process_recv(struct ishtp_cl *cros_ish_cl, 218 struct ishtp_cl_rb *rb_in_proc, ktime_t timestamp) 219 { 220 size_t data_len = rb_in_proc->buf_idx; 221 struct ishtp_cl_data *client_data = 222 ishtp_get_client_data(cros_ish_cl); 223 struct device *dev = cl_data_to_dev(client_data); 224 struct cros_ish_in_msg *in_msg = 225 (struct cros_ish_in_msg *)rb_in_proc->buffer.data; 226 227 /* Proceed only if reset or init is not in progress */ 228 if (!down_read_trylock(&init_lock)) { 229 /* Free the buffer */ 230 ishtp_cl_io_rb_recycle(rb_in_proc); 231 dev_warn(dev, 232 "Host is not ready to receive incoming messages\n"); 233 return; 234 } 235 236 /* 237 * All firmware messages contain a header. Check the buffer size 238 * before accessing elements inside. 239 */ 240 if (!rb_in_proc->buffer.data) { 241 dev_warn(dev, "rb_in_proc->buffer.data returned null"); 242 client_data->response.error = -EBADMSG; 243 goto end_error; 244 } 245 246 if (data_len < sizeof(struct header)) { 247 dev_err(dev, "data size %zu is less than header %zu\n", 248 data_len, sizeof(struct header)); 249 client_data->response.error = -EMSGSIZE; 250 goto end_error; 251 } 252 253 dev_dbg(dev, "channel=%02u status=%02u\n", 254 in_msg->hdr.channel, in_msg->hdr.status); 255 256 switch (in_msg->hdr.channel) { 257 case CROS_EC_COMMAND: 258 if (client_data->response.received) { 259 dev_err(dev, 260 "Previous firmware message not yet processed\n"); 261 goto end_error; 262 } 263 264 if (client_data->response.token != in_msg->hdr.token) { 265 dev_err_ratelimited(dev, 266 "Dropping old response token %d\n", 267 in_msg->hdr.token); 268 goto end_error; 269 } 270 271 /* Sanity check */ 272 if (!client_data->response.data) { 273 dev_err(dev, 274 "Receiving buffer is null. Should be allocated by calling function\n"); 275 client_data->response.error = -EINVAL; 276 goto error_wake_up; 277 } 278 279 if (data_len > client_data->response.max_size) { 280 dev_err(dev, 281 "Received buffer size %zu is larger than allocated buffer %zu\n", 282 data_len, client_data->response.max_size); 283 client_data->response.error = -EMSGSIZE; 284 goto error_wake_up; 285 } 286 287 if (in_msg->hdr.status) { 288 dev_err(dev, "firmware returned status %d\n", 289 in_msg->hdr.status); 290 client_data->response.error = -EIO; 291 goto error_wake_up; 292 } 293 294 /* Update the actual received buffer size */ 295 client_data->response.size = data_len; 296 297 /* 298 * Copy the buffer received in firmware response for the 299 * calling thread. 300 */ 301 memcpy(client_data->response.data, 302 rb_in_proc->buffer.data, data_len); 303 304 error_wake_up: 305 /* Free the buffer since we copied data or didn't need it */ 306 ishtp_cl_io_rb_recycle(rb_in_proc); 307 rb_in_proc = NULL; 308 309 /* Set flag before waking up the caller */ 310 client_data->response.received = true; 311 312 /* Wake the calling thread */ 313 wake_up_interruptible(&client_data->response.wait_queue); 314 315 break; 316 317 case CROS_MKBP_EVENT: 318 /* Free the buffer. This is just an event without data */ 319 ishtp_cl_io_rb_recycle(rb_in_proc); 320 rb_in_proc = NULL; 321 /* 322 * Set timestamp from beginning of function since we actually 323 * got an incoming MKBP event 324 */ 325 client_data->ec_dev->last_event_time = timestamp; 326 schedule_work(&client_data->work_ec_evt); 327 328 break; 329 330 default: 331 dev_err(dev, "Invalid channel=%02d\n", in_msg->hdr.channel); 332 } 333 334 end_error: 335 /* Free the buffer if we already haven't */ 336 if (rb_in_proc) 337 ishtp_cl_io_rb_recycle(rb_in_proc); 338 339 up_read(&init_lock); 340 } 341 342 /** 343 * ish_event_cb() - bus driver callback for incoming message 344 * @cl_device: ISHTP client device for which this message is targeted. 345 * 346 * Remove the packet from the list and process the message by calling 347 * process_recv. 348 */ 349 static void ish_event_cb(struct ishtp_cl_device *cl_device) 350 { 351 struct ishtp_cl_rb *rb_in_proc; 352 struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); 353 ktime_t timestamp; 354 355 /* 356 * Take timestamp as close to hardware interrupt as possible for sensor 357 * timestamps. 358 */ 359 timestamp = cros_ec_get_time_ns(); 360 361 while ((rb_in_proc = ishtp_cl_rx_get_rb(cros_ish_cl)) != NULL) { 362 /* Decide what to do with received data */ 363 process_recv(cros_ish_cl, rb_in_proc, timestamp); 364 } 365 } 366 367 /** 368 * cros_ish_init() - Init function for ISHTP client 369 * @cros_ish_cl: ISHTP client instance 370 * 371 * This function complete the initializtion of the client. 372 * 373 * Return: 0 for success, negative error code for failure. 374 */ 375 static int cros_ish_init(struct ishtp_cl *cros_ish_cl) 376 { 377 int rv; 378 struct ishtp_device *dev; 379 struct ishtp_fw_client *fw_client; 380 struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); 381 382 rv = ishtp_cl_link(cros_ish_cl); 383 if (rv) { 384 dev_err(cl_data_to_dev(client_data), 385 "ishtp_cl_link failed\n"); 386 return rv; 387 } 388 389 dev = ishtp_get_ishtp_device(cros_ish_cl); 390 391 /* Connect to firmware client */ 392 ishtp_set_tx_ring_size(cros_ish_cl, CROS_ISH_CL_TX_RING_SIZE); 393 ishtp_set_rx_ring_size(cros_ish_cl, CROS_ISH_CL_RX_RING_SIZE); 394 395 fw_client = ishtp_fw_cl_get_client(dev, &cros_ec_ishtp_id_table[0].guid); 396 if (!fw_client) { 397 dev_err(cl_data_to_dev(client_data), 398 "ish client uuid not found\n"); 399 rv = -ENOENT; 400 goto err_cl_unlink; 401 } 402 403 ishtp_cl_set_fw_client_id(cros_ish_cl, 404 ishtp_get_fw_client_id(fw_client)); 405 ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_CONNECTING); 406 407 rv = ishtp_cl_connect(cros_ish_cl); 408 if (rv) { 409 dev_err(cl_data_to_dev(client_data), 410 "client connect fail\n"); 411 goto err_cl_unlink; 412 } 413 414 ishtp_register_event_cb(client_data->cl_device, ish_event_cb); 415 return 0; 416 417 err_cl_unlink: 418 ishtp_cl_unlink(cros_ish_cl); 419 return rv; 420 } 421 422 /** 423 * cros_ish_deinit() - Deinit function for ISHTP client 424 * @cros_ish_cl: ISHTP client instance 425 * 426 * Unlink and free cros_ec client 427 */ 428 static void cros_ish_deinit(struct ishtp_cl *cros_ish_cl) 429 { 430 ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_DISCONNECTING); 431 ishtp_cl_disconnect(cros_ish_cl); 432 ishtp_cl_unlink(cros_ish_cl); 433 ishtp_cl_flush_queues(cros_ish_cl); 434 435 /* Disband and free all Tx and Rx client-level rings */ 436 ishtp_cl_free(cros_ish_cl); 437 } 438 439 /** 440 * prepare_cros_ec_rx() - Check & prepare receive buffer 441 * @ec_dev: CrOS EC MFD device. 442 * @in_msg: Incoming message buffer 443 * @msg: cros_ec command used to send & receive data 444 * 445 * Return: 0 for success, negative error code for failure. 446 * 447 * Check the received buffer. Convert to cros_ec_command format. 448 */ 449 static int prepare_cros_ec_rx(struct cros_ec_device *ec_dev, 450 const struct cros_ish_in_msg *in_msg, 451 struct cros_ec_command *msg) 452 { 453 u8 sum = 0; 454 int i, rv, offset; 455 456 /* Check response error code */ 457 msg->result = in_msg->ec_response.result; 458 rv = cros_ec_check_result(ec_dev, msg); 459 if (rv < 0) 460 return rv; 461 462 if (in_msg->ec_response.data_len > msg->insize) { 463 dev_err(ec_dev->dev, "Packet too long (%d bytes, expected %d)", 464 in_msg->ec_response.data_len, msg->insize); 465 return -ENOSPC; 466 } 467 468 /* Copy response packet payload and compute checksum */ 469 for (i = 0; i < sizeof(struct ec_host_response); i++) 470 sum += ((u8 *)in_msg)[IN_MSG_EC_RESPONSE_PREAMBLE + i]; 471 472 offset = sizeof(struct cros_ish_in_msg); 473 for (i = 0; i < in_msg->ec_response.data_len; i++) 474 sum += msg->data[i] = ((u8 *)in_msg)[offset + i]; 475 476 if (sum) { 477 dev_dbg(ec_dev->dev, "Bad received packet checksum %d\n", sum); 478 return -EBADMSG; 479 } 480 481 return 0; 482 } 483 484 static int cros_ec_pkt_xfer_ish(struct cros_ec_device *ec_dev, 485 struct cros_ec_command *msg) 486 { 487 int rv; 488 struct ishtp_cl *cros_ish_cl = ec_dev->priv; 489 struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); 490 struct device *dev = cl_data_to_dev(client_data); 491 struct cros_ish_in_msg *in_msg = (struct cros_ish_in_msg *)ec_dev->din; 492 struct cros_ish_out_msg *out_msg = 493 (struct cros_ish_out_msg *)ec_dev->dout; 494 size_t in_size = sizeof(struct cros_ish_in_msg) + msg->insize; 495 size_t out_size = sizeof(struct cros_ish_out_msg) + msg->outsize; 496 497 /* Sanity checks */ 498 if (in_size > ec_dev->din_size) { 499 dev_err(dev, 500 "Incoming payload size %zu is too large for ec_dev->din_size %d\n", 501 in_size, ec_dev->din_size); 502 return -EMSGSIZE; 503 } 504 505 if (out_size > ec_dev->dout_size) { 506 dev_err(dev, 507 "Outgoing payload size %zu is too large for ec_dev->dout_size %d\n", 508 out_size, ec_dev->dout_size); 509 return -EMSGSIZE; 510 } 511 512 /* Proceed only if reset-init is not in progress */ 513 if (!down_read_trylock(&init_lock)) { 514 dev_warn(dev, 515 "Host is not ready to send messages to ISH. Try again\n"); 516 return -EAGAIN; 517 } 518 519 /* Prepare the package to be sent over ISH TP */ 520 out_msg->hdr.channel = CROS_EC_COMMAND; 521 out_msg->hdr.status = 0; 522 523 ec_dev->dout += OUT_MSG_EC_REQUEST_PREAMBLE; 524 rv = cros_ec_prepare_tx(ec_dev, msg); 525 if (rv < 0) 526 goto end_error; 527 ec_dev->dout -= OUT_MSG_EC_REQUEST_PREAMBLE; 528 529 dev_dbg(dev, 530 "out_msg: struct_ver=0x%x checksum=0x%x command=0x%x command_ver=0x%x data_len=0x%x\n", 531 out_msg->ec_request.struct_version, 532 out_msg->ec_request.checksum, 533 out_msg->ec_request.command, 534 out_msg->ec_request.command_version, 535 out_msg->ec_request.data_len); 536 537 /* Send command to ISH EC firmware and read response */ 538 rv = ish_send(client_data, 539 (u8 *)out_msg, out_size, 540 (u8 *)in_msg, in_size); 541 if (rv < 0) 542 goto end_error; 543 544 rv = prepare_cros_ec_rx(ec_dev, in_msg, msg); 545 if (rv) 546 goto end_error; 547 548 rv = in_msg->ec_response.data_len; 549 550 dev_dbg(dev, 551 "in_msg: struct_ver=0x%x checksum=0x%x result=0x%x data_len=0x%x\n", 552 in_msg->ec_response.struct_version, 553 in_msg->ec_response.checksum, 554 in_msg->ec_response.result, 555 in_msg->ec_response.data_len); 556 557 end_error: 558 if (msg->command == EC_CMD_REBOOT_EC) 559 msleep(EC_REBOOT_DELAY_MS); 560 561 up_read(&init_lock); 562 563 return rv; 564 } 565 566 static int cros_ec_dev_init(struct ishtp_cl_data *client_data) 567 { 568 struct cros_ec_device *ec_dev; 569 struct device *dev = cl_data_to_dev(client_data); 570 571 ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL); 572 if (!ec_dev) 573 return -ENOMEM; 574 575 client_data->ec_dev = ec_dev; 576 dev->driver_data = ec_dev; 577 578 ec_dev->dev = dev; 579 ec_dev->priv = client_data->cros_ish_cl; 580 ec_dev->cmd_xfer = NULL; 581 ec_dev->pkt_xfer = cros_ec_pkt_xfer_ish; 582 ec_dev->phys_name = dev_name(dev); 583 ec_dev->din_size = sizeof(struct cros_ish_in_msg) + 584 sizeof(struct ec_response_get_protocol_info); 585 ec_dev->dout_size = sizeof(struct cros_ish_out_msg); 586 587 return cros_ec_register(ec_dev); 588 } 589 590 static void reset_handler(struct work_struct *work) 591 { 592 int rv; 593 struct device *dev; 594 struct ishtp_cl *cros_ish_cl; 595 struct ishtp_cl_device *cl_device; 596 struct ishtp_cl_data *client_data = 597 container_of(work, struct ishtp_cl_data, work_ishtp_reset); 598 599 /* Lock for reset to complete */ 600 down_write(&init_lock); 601 602 cros_ish_cl = client_data->cros_ish_cl; 603 cl_device = client_data->cl_device; 604 605 /* Unlink, flush queues & start again */ 606 ishtp_cl_unlink(cros_ish_cl); 607 ishtp_cl_flush_queues(cros_ish_cl); 608 ishtp_cl_free(cros_ish_cl); 609 610 cros_ish_cl = ishtp_cl_allocate(cl_device); 611 if (!cros_ish_cl) { 612 up_write(&init_lock); 613 return; 614 } 615 616 ishtp_set_drvdata(cl_device, cros_ish_cl); 617 ishtp_set_client_data(cros_ish_cl, client_data); 618 client_data->cros_ish_cl = cros_ish_cl; 619 620 rv = cros_ish_init(cros_ish_cl); 621 if (rv) { 622 ishtp_cl_free(cros_ish_cl); 623 dev_err(cl_data_to_dev(client_data), "Reset Failed\n"); 624 up_write(&init_lock); 625 return; 626 } 627 628 /* Refresh ec_dev device pointers */ 629 client_data->ec_dev->priv = client_data->cros_ish_cl; 630 dev = cl_data_to_dev(client_data); 631 dev->driver_data = client_data->ec_dev; 632 633 dev_info(cl_data_to_dev(client_data), "Chrome EC ISH reset done\n"); 634 635 up_write(&init_lock); 636 } 637 638 /** 639 * cros_ec_ishtp_probe() - ISHTP client driver probe callback 640 * @cl_device: ISHTP client device instance 641 * 642 * Return: 0 for success, negative error code for failure. 643 */ 644 static int cros_ec_ishtp_probe(struct ishtp_cl_device *cl_device) 645 { 646 int rv; 647 struct ishtp_cl *cros_ish_cl; 648 struct ishtp_cl_data *client_data = 649 devm_kzalloc(ishtp_device(cl_device), 650 sizeof(*client_data), GFP_KERNEL); 651 if (!client_data) 652 return -ENOMEM; 653 654 /* Lock for initialization to complete */ 655 down_write(&init_lock); 656 657 cros_ish_cl = ishtp_cl_allocate(cl_device); 658 if (!cros_ish_cl) { 659 rv = -ENOMEM; 660 goto end_ishtp_cl_alloc_error; 661 } 662 663 ishtp_set_drvdata(cl_device, cros_ish_cl); 664 ishtp_set_client_data(cros_ish_cl, client_data); 665 client_data->cros_ish_cl = cros_ish_cl; 666 client_data->cl_device = cl_device; 667 668 init_waitqueue_head(&client_data->response.wait_queue); 669 670 INIT_WORK(&client_data->work_ishtp_reset, 671 reset_handler); 672 INIT_WORK(&client_data->work_ec_evt, 673 ish_evt_handler); 674 675 rv = cros_ish_init(cros_ish_cl); 676 if (rv) 677 goto end_ishtp_cl_init_error; 678 679 ishtp_get_device(cl_device); 680 681 up_write(&init_lock); 682 683 /* Register croc_ec_dev mfd */ 684 rv = cros_ec_dev_init(client_data); 685 if (rv) { 686 down_write(&init_lock); 687 goto end_cros_ec_dev_init_error; 688 } 689 690 return 0; 691 692 end_cros_ec_dev_init_error: 693 ishtp_set_connection_state(cros_ish_cl, ISHTP_CL_DISCONNECTING); 694 ishtp_cl_disconnect(cros_ish_cl); 695 ishtp_cl_unlink(cros_ish_cl); 696 ishtp_cl_flush_queues(cros_ish_cl); 697 ishtp_put_device(cl_device); 698 end_ishtp_cl_init_error: 699 ishtp_cl_free(cros_ish_cl); 700 end_ishtp_cl_alloc_error: 701 up_write(&init_lock); 702 return rv; 703 } 704 705 /** 706 * cros_ec_ishtp_remove() - ISHTP client driver remove callback 707 * @cl_device: ISHTP client device instance 708 * 709 * Return: 0 710 */ 711 static void cros_ec_ishtp_remove(struct ishtp_cl_device *cl_device) 712 { 713 struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); 714 struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); 715 716 cancel_work_sync(&client_data->work_ishtp_reset); 717 cancel_work_sync(&client_data->work_ec_evt); 718 cros_ish_deinit(cros_ish_cl); 719 ishtp_put_device(cl_device); 720 } 721 722 /** 723 * cros_ec_ishtp_reset() - ISHTP client driver reset callback 724 * @cl_device: ISHTP client device instance 725 * 726 * Return: 0 727 */ 728 static int cros_ec_ishtp_reset(struct ishtp_cl_device *cl_device) 729 { 730 struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); 731 struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); 732 733 schedule_work(&client_data->work_ishtp_reset); 734 735 return 0; 736 } 737 738 /** 739 * cros_ec_ishtp_suspend() - ISHTP client driver suspend callback 740 * @device: device instance 741 * 742 * Return: 0 for success, negative error code for failure. 743 */ 744 static int __maybe_unused cros_ec_ishtp_suspend(struct device *device) 745 { 746 struct ishtp_cl_device *cl_device = ishtp_dev_to_cl_device(device); 747 struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); 748 struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); 749 750 return cros_ec_suspend(client_data->ec_dev); 751 } 752 753 /** 754 * cros_ec_ishtp_resume() - ISHTP client driver resume callback 755 * @device: device instance 756 * 757 * Return: 0 for success, negative error code for failure. 758 */ 759 static int __maybe_unused cros_ec_ishtp_resume(struct device *device) 760 { 761 struct ishtp_cl_device *cl_device = ishtp_dev_to_cl_device(device); 762 struct ishtp_cl *cros_ish_cl = ishtp_get_drvdata(cl_device); 763 struct ishtp_cl_data *client_data = ishtp_get_client_data(cros_ish_cl); 764 765 return cros_ec_resume(client_data->ec_dev); 766 } 767 768 static SIMPLE_DEV_PM_OPS(cros_ec_ishtp_pm_ops, cros_ec_ishtp_suspend, 769 cros_ec_ishtp_resume); 770 771 static struct ishtp_cl_driver cros_ec_ishtp_driver = { 772 .name = "cros_ec_ishtp", 773 .id = cros_ec_ishtp_id_table, 774 .probe = cros_ec_ishtp_probe, 775 .remove = cros_ec_ishtp_remove, 776 .reset = cros_ec_ishtp_reset, 777 .driver = { 778 .pm = &cros_ec_ishtp_pm_ops, 779 }, 780 }; 781 782 static int __init cros_ec_ishtp_mod_init(void) 783 { 784 return ishtp_cl_driver_register(&cros_ec_ishtp_driver, THIS_MODULE); 785 } 786 787 static void __exit cros_ec_ishtp_mod_exit(void) 788 { 789 ishtp_cl_driver_unregister(&cros_ec_ishtp_driver); 790 } 791 792 module_init(cros_ec_ishtp_mod_init); 793 module_exit(cros_ec_ishtp_mod_exit); 794 795 MODULE_DESCRIPTION("ChromeOS EC ISHTP Client Driver"); 796 MODULE_AUTHOR("Rushikesh S Kadam <rushikesh.s.kadam@intel.com>"); 797 798 MODULE_LICENSE("GPL v2"); 799