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