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