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 */
ish_evt_handler(struct work_struct * work)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 */
ish_send(struct ishtp_cl_data * client_data,u8 * out_msg,size_t out_size,u8 * in_msg,size_t in_size)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 */
process_recv(struct ishtp_cl * cros_ish_cl,struct ishtp_cl_rb * rb_in_proc,ktime_t timestamp)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 */
ish_event_cb(struct ishtp_cl_device * cl_device)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 */
cros_ish_init(struct ishtp_cl * cros_ish_cl)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 */
cros_ish_deinit(struct ishtp_cl * cros_ish_cl)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 */
prepare_cros_ec_rx(struct cros_ec_device * ec_dev,const struct cros_ish_in_msg * in_msg,struct cros_ec_command * msg)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
cros_ec_pkt_xfer_ish(struct cros_ec_device * ec_dev,struct cros_ec_command * msg)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
cros_ec_dev_init(struct ishtp_cl_data * client_data)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
reset_handler(struct work_struct * work)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 */
cros_ec_ishtp_probe(struct ishtp_cl_device * cl_device)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 */
cros_ec_ishtp_remove(struct ishtp_cl_device * cl_device)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 */
cros_ec_ishtp_reset(struct ishtp_cl_device * cl_device)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 */
cros_ec_ishtp_suspend(struct device * device)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 */
cros_ec_ishtp_resume(struct device * device)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
cros_ec_ishtp_mod_init(void)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
cros_ec_ishtp_mod_exit(void)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