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1/*
2 * ChromeOS EC communication protocol helper functions
3 *
4 * Copyright (C) 2015 Google, Inc
5 *
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 */
16
17#include <linux/mfd/cros_ec.h>
18#include <linux/delay.h>
19#include <linux/device.h>
20#include <linux/module.h>
21#include <linux/slab.h>
22
23#define EC_COMMAND_RETRIES 50
24
25static int prepare_packet(struct cros_ec_device *ec_dev,
26 struct cros_ec_command *msg)
27{
28 struct ec_host_request *request;
29 u8 *out;
30 int i;
31 u8 csum = 0;
32
33 BUG_ON(ec_dev->proto_version != EC_HOST_REQUEST_VERSION);
34 BUG_ON(msg->outsize + sizeof(*request) > ec_dev->dout_size);
35
36 out = ec_dev->dout;
37 request = (struct ec_host_request *)out;
38 request->struct_version = EC_HOST_REQUEST_VERSION;
39 request->checksum = 0;
40 request->command = msg->command;
41 request->command_version = msg->version;
42 request->reserved = 0;
43 request->data_len = msg->outsize;
44
45 for (i = 0; i < sizeof(*request); i++)
46 csum += out[i];
47
48 /* Copy data and update checksum */
49 memcpy(out + sizeof(*request), msg->data, msg->outsize);
50 for (i = 0; i < msg->outsize; i++)
51 csum += msg->data[i];
52
53 request->checksum = -csum;
54
55 return sizeof(*request) + msg->outsize;
56}
57
58static int send_command(struct cros_ec_device *ec_dev,
59 struct cros_ec_command *msg)
60{
61 int ret;
62
63 if (ec_dev->proto_version > 2)
64 ret = ec_dev->pkt_xfer(ec_dev, msg);
65 else
66 ret = ec_dev->cmd_xfer(ec_dev, msg);
67
68 if (msg->result == EC_RES_IN_PROGRESS) {
69 int i;
70 struct cros_ec_command *status_msg;
71 struct ec_response_get_comms_status *status;
72
73 status_msg = kmalloc(sizeof(*status_msg) + sizeof(*status),
74 GFP_KERNEL);
75 if (!status_msg)
76 return -ENOMEM;
77
78 status_msg->version = 0;
79 status_msg->command = EC_CMD_GET_COMMS_STATUS;
80 status_msg->insize = sizeof(*status);
81 status_msg->outsize = 0;
82
83 /*
84 * Query the EC's status until it's no longer busy or
85 * we encounter an error.
86 */
87 for (i = 0; i < EC_COMMAND_RETRIES; i++) {
88 usleep_range(10000, 11000);
89
90 ret = ec_dev->cmd_xfer(ec_dev, status_msg);
91 if (ret < 0)
92 break;
93
94 msg->result = status_msg->result;
95 if (status_msg->result != EC_RES_SUCCESS)
96 break;
97
98 status = (struct ec_response_get_comms_status *)
99 status_msg->data;
100 if (!(status->flags & EC_COMMS_STATUS_PROCESSING))
101 break;
102 }
103
104 kfree(status_msg);
105 }
106
107 return ret;
108}
109
110int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
111 struct cros_ec_command *msg)
112{
113 u8 *out;
114 u8 csum;
115 int i;
116
117 if (ec_dev->proto_version > 2)
118 return prepare_packet(ec_dev, msg);
119
120 BUG_ON(msg->outsize > EC_PROTO2_MAX_PARAM_SIZE);
121 out = ec_dev->dout;
122 out[0] = EC_CMD_VERSION0 + msg->version;
123 out[1] = msg->command;
124 out[2] = msg->outsize;
125 csum = out[0] + out[1] + out[2];
126 for (i = 0; i < msg->outsize; i++)
127 csum += out[EC_MSG_TX_HEADER_BYTES + i] = msg->data[i];
128 out[EC_MSG_TX_HEADER_BYTES + msg->outsize] = csum;
129
130 return EC_MSG_TX_PROTO_BYTES + msg->outsize;
131}
132EXPORT_SYMBOL(cros_ec_prepare_tx);
133
134int cros_ec_check_result(struct cros_ec_device *ec_dev,
135 struct cros_ec_command *msg)
136{
137 switch (msg->result) {
138 case EC_RES_SUCCESS:
139 return 0;
140 case EC_RES_IN_PROGRESS:
141 dev_dbg(ec_dev->dev, "command 0x%02x in progress\n",
142 msg->command);
143 return -EAGAIN;
144 default:
145 dev_dbg(ec_dev->dev, "command 0x%02x returned %d\n",
146 msg->command, msg->result);
147 return 0;
148 }
149}
150EXPORT_SYMBOL(cros_ec_check_result);
151
152static int cros_ec_host_command_proto_query(struct cros_ec_device *ec_dev,
153 int devidx,
154 struct cros_ec_command *msg)
155{
156 /*
157 * Try using v3+ to query for supported protocols. If this
158 * command fails, fall back to v2. Returns the highest protocol
159 * supported by the EC.
160 * Also sets the max request/response/passthru size.
161 */
162 int ret;
163
164 if (!ec_dev->pkt_xfer)
165 return -EPROTONOSUPPORT;
166
167 memset(msg, 0, sizeof(*msg));
168 msg->command = EC_CMD_PASSTHRU_OFFSET(devidx) | EC_CMD_GET_PROTOCOL_INFO;
169 msg->insize = sizeof(struct ec_response_get_protocol_info);
170
171 ret = send_command(ec_dev, msg);
172
173 if (ret < 0) {
174 dev_dbg(ec_dev->dev,
175 "failed to check for EC[%d] protocol version: %d\n",
176 devidx, ret);
177 return ret;
178 }
179
180 if (devidx > 0 && msg->result == EC_RES_INVALID_COMMAND)
181 return -ENODEV;
182 else if (msg->result != EC_RES_SUCCESS)
183 return msg->result;
184
185 return 0;
186}
187
188static int cros_ec_host_command_proto_query_v2(struct cros_ec_device *ec_dev)
189{
190 struct cros_ec_command *msg;
191 struct ec_params_hello *hello_params;
192 struct ec_response_hello *hello_response;
193 int ret;
194 int len = max(sizeof(*hello_params), sizeof(*hello_response));
195
196 msg = kmalloc(sizeof(*msg) + len, GFP_KERNEL);
197 if (!msg)
198 return -ENOMEM;
199
200 msg->version = 0;
201 msg->command = EC_CMD_HELLO;
202 hello_params = (struct ec_params_hello *)msg->data;
203 msg->outsize = sizeof(*hello_params);
204 hello_response = (struct ec_response_hello *)msg->data;
205 msg->insize = sizeof(*hello_response);
206
207 hello_params->in_data = 0xa0b0c0d0;
208
209 ret = send_command(ec_dev, msg);
210
211 if (ret < 0) {
212 dev_dbg(ec_dev->dev,
213 "EC failed to respond to v2 hello: %d\n",
214 ret);
215 goto exit;
216 } else if (msg->result != EC_RES_SUCCESS) {
217 dev_err(ec_dev->dev,
218 "EC responded to v2 hello with error: %d\n",
219 msg->result);
220 ret = msg->result;
221 goto exit;
222 } else if (hello_response->out_data != 0xa1b2c3d4) {
223 dev_err(ec_dev->dev,
224 "EC responded to v2 hello with bad result: %u\n",
225 hello_response->out_data);
226 ret = -EBADMSG;
227 goto exit;
228 }
229
230 ret = 0;
231
232 exit:
233 kfree(msg);
234 return ret;
235}
236
237int cros_ec_query_all(struct cros_ec_device *ec_dev)
238{
239 struct device *dev = ec_dev->dev;
240 struct cros_ec_command *proto_msg;
241 struct ec_response_get_protocol_info *proto_info;
242 int ret;
243
244 proto_msg = kzalloc(sizeof(*proto_msg) + sizeof(*proto_info),
245 GFP_KERNEL);
246 if (!proto_msg)
247 return -ENOMEM;
248
249 /* First try sending with proto v3. */
250 ec_dev->proto_version = 3;
251 ret = cros_ec_host_command_proto_query(ec_dev, 0, proto_msg);
252
253 if (ret == 0) {
254 proto_info = (struct ec_response_get_protocol_info *)
255 proto_msg->data;
256 ec_dev->max_request = proto_info->max_request_packet_size -
257 sizeof(struct ec_host_request);
258 ec_dev->max_response = proto_info->max_response_packet_size -
259 sizeof(struct ec_host_response);
260 ec_dev->proto_version =
261 min(EC_HOST_REQUEST_VERSION,
262 fls(proto_info->protocol_versions) - 1);
263 dev_dbg(ec_dev->dev,
264 "using proto v%u\n",
265 ec_dev->proto_version);
266
267 ec_dev->din_size = ec_dev->max_response +
268 sizeof(struct ec_host_response) +
269 EC_MAX_RESPONSE_OVERHEAD;
270 ec_dev->dout_size = ec_dev->max_request +
271 sizeof(struct ec_host_request) +
272 EC_MAX_REQUEST_OVERHEAD;
273
274 /*
275 * Check for PD
276 */
277 ret = cros_ec_host_command_proto_query(ec_dev, 1, proto_msg);
278
279 if (ret) {
280 dev_dbg(ec_dev->dev, "no PD chip found: %d\n", ret);
281 ec_dev->max_passthru = 0;
282 } else {
283 dev_dbg(ec_dev->dev, "found PD chip\n");
284 ec_dev->max_passthru =
285 proto_info->max_request_packet_size -
286 sizeof(struct ec_host_request);
287 }
288 } else {
289 /* Try querying with a v2 hello message. */
290 ec_dev->proto_version = 2;
291 ret = cros_ec_host_command_proto_query_v2(ec_dev);
292
293 if (ret == 0) {
294 /* V2 hello succeeded. */
295 dev_dbg(ec_dev->dev, "falling back to proto v2\n");
296
297 ec_dev->max_request = EC_PROTO2_MAX_PARAM_SIZE;
298 ec_dev->max_response = EC_PROTO2_MAX_PARAM_SIZE;
299 ec_dev->max_passthru = 0;
300 ec_dev->pkt_xfer = NULL;
301 ec_dev->din_size = EC_MSG_BYTES;
302 ec_dev->dout_size = EC_MSG_BYTES;
303 } else {
304 /*
305 * It's possible for a test to occur too early when
306 * the EC isn't listening. If this happens, we'll
307 * test later when the first command is run.
308 */
309 ec_dev->proto_version = EC_PROTO_VERSION_UNKNOWN;
310 dev_dbg(ec_dev->dev, "EC query failed: %d\n", ret);
311 goto exit;
312 }
313 }
314
315 devm_kfree(dev, ec_dev->din);
316 devm_kfree(dev, ec_dev->dout);
317
318 ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
319 if (!ec_dev->din) {
320 ret = -ENOMEM;
321 goto exit;
322 }
323
324 ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
325 if (!ec_dev->dout) {
326 devm_kfree(dev, ec_dev->din);
327 ret = -ENOMEM;
328 goto exit;
329 }
330
331exit:
332 kfree(proto_msg);
333 return ret;
334}
335EXPORT_SYMBOL(cros_ec_query_all);
336
337int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
338 struct cros_ec_command *msg)
339{
340 int ret;
341
342 mutex_lock(&ec_dev->lock);
343 if (ec_dev->proto_version == EC_PROTO_VERSION_UNKNOWN) {
344 ret = cros_ec_query_all(ec_dev);
345 if (ret) {
346 dev_err(ec_dev->dev,
347 "EC version unknown and query failed; aborting command\n");
348 mutex_unlock(&ec_dev->lock);
349 return ret;
350 }
351 }
352
353 if (msg->insize > ec_dev->max_response) {
354 dev_dbg(ec_dev->dev, "clamping message receive buffer\n");
355 msg->insize = ec_dev->max_response;
356 }
357
358 if (msg->command < EC_CMD_PASSTHRU_OFFSET(1)) {
359 if (msg->outsize > ec_dev->max_request) {
360 dev_err(ec_dev->dev,
361 "request of size %u is too big (max: %u)\n",
362 msg->outsize,
363 ec_dev->max_request);
364 mutex_unlock(&ec_dev->lock);
365 return -EMSGSIZE;
366 }
367 } else {
368 if (msg->outsize > ec_dev->max_passthru) {
369 dev_err(ec_dev->dev,
370 "passthru rq of size %u is too big (max: %u)\n",
371 msg->outsize,
372 ec_dev->max_passthru);
373 mutex_unlock(&ec_dev->lock);
374 return -EMSGSIZE;
375 }
376 }
377 ret = send_command(ec_dev, msg);
378 mutex_unlock(&ec_dev->lock);
379
380 return ret;
381}
382EXPORT_SYMBOL(cros_ec_cmd_xfer);
1// SPDX-License-Identifier: GPL-2.0
2// ChromeOS EC communication protocol helper functions
3//
4// Copyright (C) 2015 Google, Inc
5
6#include <linux/delay.h>
7#include <linux/device.h>
8#include <linux/module.h>
9#include <linux/platform_data/cros_ec_commands.h>
10#include <linux/platform_data/cros_ec_proto.h>
11#include <linux/slab.h>
12#include <asm/unaligned.h>
13
14#include "cros_ec_trace.h"
15
16#define EC_COMMAND_RETRIES 50
17
18static const int cros_ec_error_map[] = {
19 [EC_RES_INVALID_COMMAND] = -EOPNOTSUPP,
20 [EC_RES_ERROR] = -EIO,
21 [EC_RES_INVALID_PARAM] = -EINVAL,
22 [EC_RES_ACCESS_DENIED] = -EACCES,
23 [EC_RES_INVALID_RESPONSE] = -EPROTO,
24 [EC_RES_INVALID_VERSION] = -ENOPROTOOPT,
25 [EC_RES_INVALID_CHECKSUM] = -EBADMSG,
26 [EC_RES_IN_PROGRESS] = -EINPROGRESS,
27 [EC_RES_UNAVAILABLE] = -ENODATA,
28 [EC_RES_TIMEOUT] = -ETIMEDOUT,
29 [EC_RES_OVERFLOW] = -EOVERFLOW,
30 [EC_RES_INVALID_HEADER] = -EBADR,
31 [EC_RES_REQUEST_TRUNCATED] = -EBADR,
32 [EC_RES_RESPONSE_TOO_BIG] = -EFBIG,
33 [EC_RES_BUS_ERROR] = -EFAULT,
34 [EC_RES_BUSY] = -EBUSY,
35 [EC_RES_INVALID_HEADER_VERSION] = -EBADMSG,
36 [EC_RES_INVALID_HEADER_CRC] = -EBADMSG,
37 [EC_RES_INVALID_DATA_CRC] = -EBADMSG,
38 [EC_RES_DUP_UNAVAILABLE] = -ENODATA,
39};
40
41static int cros_ec_map_error(uint32_t result)
42{
43 int ret = 0;
44
45 if (result != EC_RES_SUCCESS) {
46 if (result < ARRAY_SIZE(cros_ec_error_map) && cros_ec_error_map[result])
47 ret = cros_ec_error_map[result];
48 else
49 ret = -EPROTO;
50 }
51
52 return ret;
53}
54
55static int prepare_tx(struct cros_ec_device *ec_dev,
56 struct cros_ec_command *msg)
57{
58 struct ec_host_request *request;
59 u8 *out;
60 int i;
61 u8 csum = 0;
62
63 if (msg->outsize + sizeof(*request) > ec_dev->dout_size)
64 return -EINVAL;
65
66 out = ec_dev->dout;
67 request = (struct ec_host_request *)out;
68 request->struct_version = EC_HOST_REQUEST_VERSION;
69 request->checksum = 0;
70 request->command = msg->command;
71 request->command_version = msg->version;
72 request->reserved = 0;
73 request->data_len = msg->outsize;
74
75 for (i = 0; i < sizeof(*request); i++)
76 csum += out[i];
77
78 /* Copy data and update checksum */
79 memcpy(out + sizeof(*request), msg->data, msg->outsize);
80 for (i = 0; i < msg->outsize; i++)
81 csum += msg->data[i];
82
83 request->checksum = -csum;
84
85 return sizeof(*request) + msg->outsize;
86}
87
88static int prepare_tx_legacy(struct cros_ec_device *ec_dev,
89 struct cros_ec_command *msg)
90{
91 u8 *out;
92 u8 csum;
93 int i;
94
95 if (msg->outsize > EC_PROTO2_MAX_PARAM_SIZE)
96 return -EINVAL;
97
98 out = ec_dev->dout;
99 out[0] = EC_CMD_VERSION0 + msg->version;
100 out[1] = msg->command;
101 out[2] = msg->outsize;
102 csum = out[0] + out[1] + out[2];
103 for (i = 0; i < msg->outsize; i++)
104 csum += out[EC_MSG_TX_HEADER_BYTES + i] = msg->data[i];
105 out[EC_MSG_TX_HEADER_BYTES + msg->outsize] = csum;
106
107 return EC_MSG_TX_PROTO_BYTES + msg->outsize;
108}
109
110static int cros_ec_xfer_command(struct cros_ec_device *ec_dev, struct cros_ec_command *msg)
111{
112 int ret;
113 int (*xfer_fxn)(struct cros_ec_device *ec, struct cros_ec_command *msg);
114
115 if (ec_dev->proto_version > 2)
116 xfer_fxn = ec_dev->pkt_xfer;
117 else
118 xfer_fxn = ec_dev->cmd_xfer;
119
120 if (!xfer_fxn) {
121 /*
122 * This error can happen if a communication error happened and
123 * the EC is trying to use protocol v2, on an underlying
124 * communication mechanism that does not support v2.
125 */
126 dev_err_once(ec_dev->dev, "missing EC transfer API, cannot send command\n");
127 return -EIO;
128 }
129
130 trace_cros_ec_request_start(msg);
131 ret = (*xfer_fxn)(ec_dev, msg);
132 trace_cros_ec_request_done(msg, ret);
133
134 return ret;
135}
136
137static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t *result)
138{
139 struct {
140 struct cros_ec_command msg;
141 struct ec_response_get_comms_status status;
142 } __packed buf;
143 struct cros_ec_command *msg = &buf.msg;
144 struct ec_response_get_comms_status *status = &buf.status;
145 int ret = 0, i;
146
147 msg->version = 0;
148 msg->command = EC_CMD_GET_COMMS_STATUS;
149 msg->insize = sizeof(*status);
150 msg->outsize = 0;
151
152 /* Query the EC's status until it's no longer busy or we encounter an error. */
153 for (i = 0; i < EC_COMMAND_RETRIES; ++i) {
154 usleep_range(10000, 11000);
155
156 ret = cros_ec_xfer_command(ec_dev, msg);
157 if (ret == -EAGAIN)
158 continue;
159 if (ret < 0)
160 return ret;
161
162 *result = msg->result;
163 if (msg->result != EC_RES_SUCCESS)
164 return ret;
165
166 if (ret == 0) {
167 ret = -EPROTO;
168 break;
169 }
170
171 if (!(status->flags & EC_COMMS_STATUS_PROCESSING))
172 return ret;
173 }
174
175 if (i >= EC_COMMAND_RETRIES)
176 ret = -EAGAIN;
177
178 return ret;
179}
180
181static int cros_ec_send_command(struct cros_ec_device *ec_dev, struct cros_ec_command *msg)
182{
183 int ret = cros_ec_xfer_command(ec_dev, msg);
184
185 if (msg->result == EC_RES_IN_PROGRESS)
186 ret = cros_ec_wait_until_complete(ec_dev, &msg->result);
187
188 return ret;
189}
190
191/**
192 * cros_ec_prepare_tx() - Prepare an outgoing message in the output buffer.
193 * @ec_dev: Device to register.
194 * @msg: Message to write.
195 *
196 * This is used by all ChromeOS EC drivers to prepare the outgoing message
197 * according to different protocol versions.
198 *
199 * Return: number of prepared bytes on success or negative error code.
200 */
201int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
202 struct cros_ec_command *msg)
203{
204 if (ec_dev->proto_version > 2)
205 return prepare_tx(ec_dev, msg);
206
207 return prepare_tx_legacy(ec_dev, msg);
208}
209EXPORT_SYMBOL(cros_ec_prepare_tx);
210
211/**
212 * cros_ec_check_result() - Check ec_msg->result.
213 * @ec_dev: EC device.
214 * @msg: Message to check.
215 *
216 * This is used by ChromeOS EC drivers to check the ec_msg->result for
217 * EC_RES_IN_PROGRESS and to warn about them.
218 *
219 * The function should not check for furthermore error codes. Otherwise,
220 * it would break the ABI.
221 *
222 * Return: -EAGAIN if ec_msg->result == EC_RES_IN_PROGRESS. Otherwise, 0.
223 */
224int cros_ec_check_result(struct cros_ec_device *ec_dev,
225 struct cros_ec_command *msg)
226{
227 switch (msg->result) {
228 case EC_RES_SUCCESS:
229 return 0;
230 case EC_RES_IN_PROGRESS:
231 dev_dbg(ec_dev->dev, "command 0x%02x in progress\n",
232 msg->command);
233 return -EAGAIN;
234 default:
235 dev_dbg(ec_dev->dev, "command 0x%02x returned %d\n",
236 msg->command, msg->result);
237 return 0;
238 }
239}
240EXPORT_SYMBOL(cros_ec_check_result);
241
242/*
243 * cros_ec_get_host_event_wake_mask
244 *
245 * Get the mask of host events that cause wake from suspend.
246 *
247 * @ec_dev: EC device to call
248 * @msg: message structure to use
249 * @mask: result when function returns 0.
250 *
251 * LOCKING:
252 * the caller has ec_dev->lock mutex, or the caller knows there is
253 * no other command in progress.
254 */
255static int cros_ec_get_host_event_wake_mask(struct cros_ec_device *ec_dev, uint32_t *mask)
256{
257 struct cros_ec_command *msg;
258 struct ec_response_host_event_mask *r;
259 int ret, mapped;
260
261 msg = kzalloc(sizeof(*msg) + sizeof(*r), GFP_KERNEL);
262 if (!msg)
263 return -ENOMEM;
264
265 msg->command = EC_CMD_HOST_EVENT_GET_WAKE_MASK;
266 msg->insize = sizeof(*r);
267
268 ret = cros_ec_send_command(ec_dev, msg);
269 if (ret < 0)
270 goto exit;
271
272 mapped = cros_ec_map_error(msg->result);
273 if (mapped) {
274 ret = mapped;
275 goto exit;
276 }
277
278 if (ret == 0) {
279 ret = -EPROTO;
280 goto exit;
281 }
282
283 r = (struct ec_response_host_event_mask *)msg->data;
284 *mask = r->mask;
285 ret = 0;
286exit:
287 kfree(msg);
288 return ret;
289}
290
291static int cros_ec_get_proto_info(struct cros_ec_device *ec_dev, int devidx)
292{
293 struct cros_ec_command *msg;
294 struct ec_response_get_protocol_info *info;
295 int ret, mapped;
296
297 ec_dev->proto_version = 3;
298 if (devidx > 0)
299 ec_dev->max_passthru = 0;
300
301 msg = kzalloc(sizeof(*msg) + sizeof(*info), GFP_KERNEL);
302 if (!msg)
303 return -ENOMEM;
304
305 msg->command = EC_CMD_PASSTHRU_OFFSET(devidx) | EC_CMD_GET_PROTOCOL_INFO;
306 msg->insize = sizeof(*info);
307
308 ret = cros_ec_send_command(ec_dev, msg);
309 /*
310 * Send command once again when timeout occurred.
311 * Fingerprint MCU (FPMCU) is restarted during system boot which
312 * introduces small window in which FPMCU won't respond for any
313 * messages sent by kernel. There is no need to wait before next
314 * attempt because we waited at least EC_MSG_DEADLINE_MS.
315 */
316 if (ret == -ETIMEDOUT)
317 ret = cros_ec_send_command(ec_dev, msg);
318
319 if (ret < 0) {
320 dev_dbg(ec_dev->dev,
321 "failed to check for EC[%d] protocol version: %d\n",
322 devidx, ret);
323 goto exit;
324 }
325
326 mapped = cros_ec_map_error(msg->result);
327 if (mapped) {
328 ret = mapped;
329 goto exit;
330 }
331
332 if (ret == 0) {
333 ret = -EPROTO;
334 goto exit;
335 }
336
337 info = (struct ec_response_get_protocol_info *)msg->data;
338
339 switch (devidx) {
340 case CROS_EC_DEV_EC_INDEX:
341 ec_dev->max_request = info->max_request_packet_size -
342 sizeof(struct ec_host_request);
343 ec_dev->max_response = info->max_response_packet_size -
344 sizeof(struct ec_host_response);
345 ec_dev->proto_version = min(EC_HOST_REQUEST_VERSION,
346 fls(info->protocol_versions) - 1);
347 ec_dev->din_size = info->max_response_packet_size + EC_MAX_RESPONSE_OVERHEAD;
348 ec_dev->dout_size = info->max_request_packet_size + EC_MAX_REQUEST_OVERHEAD;
349
350 dev_dbg(ec_dev->dev, "using proto v%u\n", ec_dev->proto_version);
351 break;
352 case CROS_EC_DEV_PD_INDEX:
353 ec_dev->max_passthru = info->max_request_packet_size -
354 sizeof(struct ec_host_request);
355
356 dev_dbg(ec_dev->dev, "found PD chip\n");
357 break;
358 default:
359 dev_dbg(ec_dev->dev, "unknown passthru index: %d\n", devidx);
360 break;
361 }
362
363 ret = 0;
364exit:
365 kfree(msg);
366 return ret;
367}
368
369static int cros_ec_get_proto_info_legacy(struct cros_ec_device *ec_dev)
370{
371 struct cros_ec_command *msg;
372 struct ec_params_hello *params;
373 struct ec_response_hello *response;
374 int ret, mapped;
375
376 ec_dev->proto_version = 2;
377
378 msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*response)), GFP_KERNEL);
379 if (!msg)
380 return -ENOMEM;
381
382 msg->command = EC_CMD_HELLO;
383 msg->insize = sizeof(*response);
384 msg->outsize = sizeof(*params);
385
386 params = (struct ec_params_hello *)msg->data;
387 params->in_data = 0xa0b0c0d0;
388
389 ret = cros_ec_send_command(ec_dev, msg);
390 if (ret < 0) {
391 dev_dbg(ec_dev->dev, "EC failed to respond to v2 hello: %d\n", ret);
392 goto exit;
393 }
394
395 mapped = cros_ec_map_error(msg->result);
396 if (mapped) {
397 ret = mapped;
398 dev_err(ec_dev->dev, "EC responded to v2 hello with error: %d\n", msg->result);
399 goto exit;
400 }
401
402 if (ret == 0) {
403 ret = -EPROTO;
404 goto exit;
405 }
406
407 response = (struct ec_response_hello *)msg->data;
408 if (response->out_data != 0xa1b2c3d4) {
409 dev_err(ec_dev->dev,
410 "EC responded to v2 hello with bad result: %u\n",
411 response->out_data);
412 ret = -EBADMSG;
413 goto exit;
414 }
415
416 ec_dev->max_request = EC_PROTO2_MAX_PARAM_SIZE;
417 ec_dev->max_response = EC_PROTO2_MAX_PARAM_SIZE;
418 ec_dev->max_passthru = 0;
419 ec_dev->pkt_xfer = NULL;
420 ec_dev->din_size = EC_PROTO2_MSG_BYTES;
421 ec_dev->dout_size = EC_PROTO2_MSG_BYTES;
422
423 dev_dbg(ec_dev->dev, "falling back to proto v2\n");
424 ret = 0;
425exit:
426 kfree(msg);
427 return ret;
428}
429
430/*
431 * cros_ec_get_host_command_version_mask
432 *
433 * Get the version mask of a given command.
434 *
435 * @ec_dev: EC device to call
436 * @msg: message structure to use
437 * @cmd: command to get the version of.
438 * @mask: result when function returns 0.
439 *
440 * @return 0 on success, error code otherwise
441 *
442 * LOCKING:
443 * the caller has ec_dev->lock mutex or the caller knows there is
444 * no other command in progress.
445 */
446static int cros_ec_get_host_command_version_mask(struct cros_ec_device *ec_dev, u16 cmd, u32 *mask)
447{
448 struct ec_params_get_cmd_versions *pver;
449 struct ec_response_get_cmd_versions *rver;
450 struct cros_ec_command *msg;
451 int ret, mapped;
452
453 msg = kmalloc(sizeof(*msg) + max(sizeof(*rver), sizeof(*pver)),
454 GFP_KERNEL);
455 if (!msg)
456 return -ENOMEM;
457
458 msg->version = 0;
459 msg->command = EC_CMD_GET_CMD_VERSIONS;
460 msg->insize = sizeof(*rver);
461 msg->outsize = sizeof(*pver);
462
463 pver = (struct ec_params_get_cmd_versions *)msg->data;
464 pver->cmd = cmd;
465
466 ret = cros_ec_send_command(ec_dev, msg);
467 if (ret < 0)
468 goto exit;
469
470 mapped = cros_ec_map_error(msg->result);
471 if (mapped) {
472 ret = mapped;
473 goto exit;
474 }
475
476 if (ret == 0) {
477 ret = -EPROTO;
478 goto exit;
479 }
480
481 rver = (struct ec_response_get_cmd_versions *)msg->data;
482 *mask = rver->version_mask;
483 ret = 0;
484exit:
485 kfree(msg);
486 return ret;
487}
488
489/**
490 * cros_ec_query_all() - Query the protocol version supported by the
491 * ChromeOS EC.
492 * @ec_dev: Device to register.
493 *
494 * Return: 0 on success or negative error code.
495 */
496int cros_ec_query_all(struct cros_ec_device *ec_dev)
497{
498 struct device *dev = ec_dev->dev;
499 u32 ver_mask;
500 int ret;
501
502 /* First try sending with proto v3. */
503 if (!cros_ec_get_proto_info(ec_dev, CROS_EC_DEV_EC_INDEX)) {
504 /* Check for PD. */
505 cros_ec_get_proto_info(ec_dev, CROS_EC_DEV_PD_INDEX);
506 } else {
507 /* Try querying with a v2 hello message. */
508 ret = cros_ec_get_proto_info_legacy(ec_dev);
509 if (ret) {
510 /*
511 * It's possible for a test to occur too early when
512 * the EC isn't listening. If this happens, we'll
513 * test later when the first command is run.
514 */
515 ec_dev->proto_version = EC_PROTO_VERSION_UNKNOWN;
516 dev_dbg(ec_dev->dev, "EC query failed: %d\n", ret);
517 return ret;
518 }
519 }
520
521 devm_kfree(dev, ec_dev->din);
522 devm_kfree(dev, ec_dev->dout);
523
524 ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
525 if (!ec_dev->din) {
526 ret = -ENOMEM;
527 goto exit;
528 }
529
530 ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
531 if (!ec_dev->dout) {
532 devm_kfree(dev, ec_dev->din);
533 ret = -ENOMEM;
534 goto exit;
535 }
536
537 /* Probe if MKBP event is supported */
538 ret = cros_ec_get_host_command_version_mask(ec_dev, EC_CMD_GET_NEXT_EVENT, &ver_mask);
539 if (ret < 0 || ver_mask == 0) {
540 ec_dev->mkbp_event_supported = 0;
541 } else {
542 ec_dev->mkbp_event_supported = fls(ver_mask);
543
544 dev_dbg(ec_dev->dev, "MKBP support version %u\n", ec_dev->mkbp_event_supported - 1);
545 }
546
547 /* Probe if host sleep v1 is supported for S0ix failure detection. */
548 ret = cros_ec_get_host_command_version_mask(ec_dev, EC_CMD_HOST_SLEEP_EVENT, &ver_mask);
549 ec_dev->host_sleep_v1 = (ret == 0 && (ver_mask & EC_VER_MASK(1)));
550
551 /* Get host event wake mask. */
552 ret = cros_ec_get_host_event_wake_mask(ec_dev, &ec_dev->host_event_wake_mask);
553 if (ret < 0) {
554 /*
555 * If the EC doesn't support EC_CMD_HOST_EVENT_GET_WAKE_MASK,
556 * use a reasonable default. Note that we ignore various
557 * battery, AC status, and power-state events, because (a)
558 * those can be quite common (e.g., when sitting at full
559 * charge, on AC) and (b) these are not actionable wake events;
560 * if anything, we'd like to continue suspending (to save
561 * power), not wake up.
562 */
563 ec_dev->host_event_wake_mask = U32_MAX &
564 ~(EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_CLOSED) |
565 EC_HOST_EVENT_MASK(EC_HOST_EVENT_AC_DISCONNECTED) |
566 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_LOW) |
567 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_CRITICAL) |
568 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY) |
569 EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU) |
570 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_STATUS));
571 /*
572 * Old ECs may not support this command. Complain about all
573 * other errors.
574 */
575 if (ret != -EOPNOTSUPP)
576 dev_err(ec_dev->dev,
577 "failed to retrieve wake mask: %d\n", ret);
578 }
579
580 ret = 0;
581
582exit:
583 return ret;
584}
585EXPORT_SYMBOL(cros_ec_query_all);
586
587/**
588 * cros_ec_cmd_xfer() - Send a command to the ChromeOS EC.
589 * @ec_dev: EC device.
590 * @msg: Message to write.
591 *
592 * Call this to send a command to the ChromeOS EC. This should be used instead
593 * of calling the EC's cmd_xfer() callback directly. This function does not
594 * convert EC command execution error codes to Linux error codes. Most
595 * in-kernel users will want to use cros_ec_cmd_xfer_status() instead since
596 * that function implements the conversion.
597 *
598 * Return:
599 * >0 - EC command was executed successfully. The return value is the number
600 * of bytes returned by the EC (excluding the header).
601 * =0 - EC communication was successful. EC command execution results are
602 * reported in msg->result. The result will be EC_RES_SUCCESS if the
603 * command was executed successfully or report an EC command execution
604 * error.
605 * <0 - EC communication error. Return value is the Linux error code.
606 */
607int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, struct cros_ec_command *msg)
608{
609 int ret;
610
611 mutex_lock(&ec_dev->lock);
612 if (ec_dev->proto_version == EC_PROTO_VERSION_UNKNOWN) {
613 ret = cros_ec_query_all(ec_dev);
614 if (ret) {
615 dev_err(ec_dev->dev,
616 "EC version unknown and query failed; aborting command\n");
617 mutex_unlock(&ec_dev->lock);
618 return ret;
619 }
620 }
621
622 if (msg->insize > ec_dev->max_response) {
623 dev_dbg(ec_dev->dev, "clamping message receive buffer\n");
624 msg->insize = ec_dev->max_response;
625 }
626
627 if (msg->command < EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX)) {
628 if (msg->outsize > ec_dev->max_request) {
629 dev_err(ec_dev->dev,
630 "request of size %u is too big (max: %u)\n",
631 msg->outsize,
632 ec_dev->max_request);
633 mutex_unlock(&ec_dev->lock);
634 return -EMSGSIZE;
635 }
636 } else {
637 if (msg->outsize > ec_dev->max_passthru) {
638 dev_err(ec_dev->dev,
639 "passthru rq of size %u is too big (max: %u)\n",
640 msg->outsize,
641 ec_dev->max_passthru);
642 mutex_unlock(&ec_dev->lock);
643 return -EMSGSIZE;
644 }
645 }
646
647 ret = cros_ec_send_command(ec_dev, msg);
648 mutex_unlock(&ec_dev->lock);
649
650 return ret;
651}
652EXPORT_SYMBOL(cros_ec_cmd_xfer);
653
654/**
655 * cros_ec_cmd_xfer_status() - Send a command to the ChromeOS EC.
656 * @ec_dev: EC device.
657 * @msg: Message to write.
658 *
659 * Call this to send a command to the ChromeOS EC. This should be used instead of calling the EC's
660 * cmd_xfer() callback directly. It returns success status only if both the command was transmitted
661 * successfully and the EC replied with success status.
662 *
663 * Return:
664 * >=0 - The number of bytes transferred.
665 * <0 - Linux error code
666 */
667int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
668 struct cros_ec_command *msg)
669{
670 int ret, mapped;
671
672 ret = cros_ec_cmd_xfer(ec_dev, msg);
673 if (ret < 0)
674 return ret;
675
676 mapped = cros_ec_map_error(msg->result);
677 if (mapped) {
678 dev_dbg(ec_dev->dev, "Command result (err: %d [%d])\n",
679 msg->result, mapped);
680 ret = mapped;
681 }
682
683 return ret;
684}
685EXPORT_SYMBOL(cros_ec_cmd_xfer_status);
686
687static int get_next_event_xfer(struct cros_ec_device *ec_dev,
688 struct cros_ec_command *msg,
689 struct ec_response_get_next_event_v1 *event,
690 int version, uint32_t size)
691{
692 int ret;
693
694 msg->version = version;
695 msg->command = EC_CMD_GET_NEXT_EVENT;
696 msg->insize = size;
697 msg->outsize = 0;
698
699 ret = cros_ec_cmd_xfer_status(ec_dev, msg);
700 if (ret > 0) {
701 ec_dev->event_size = ret - 1;
702 ec_dev->event_data = *event;
703 }
704
705 return ret;
706}
707
708static int get_next_event(struct cros_ec_device *ec_dev)
709{
710 struct {
711 struct cros_ec_command msg;
712 struct ec_response_get_next_event_v1 event;
713 } __packed buf;
714 struct cros_ec_command *msg = &buf.msg;
715 struct ec_response_get_next_event_v1 *event = &buf.event;
716 const int cmd_version = ec_dev->mkbp_event_supported - 1;
717
718 memset(msg, 0, sizeof(*msg));
719 if (ec_dev->suspended) {
720 dev_dbg(ec_dev->dev, "Device suspended.\n");
721 return -EHOSTDOWN;
722 }
723
724 if (cmd_version == 0)
725 return get_next_event_xfer(ec_dev, msg, event, 0,
726 sizeof(struct ec_response_get_next_event));
727
728 return get_next_event_xfer(ec_dev, msg, event, cmd_version,
729 sizeof(struct ec_response_get_next_event_v1));
730}
731
732static int get_keyboard_state_event(struct cros_ec_device *ec_dev)
733{
734 u8 buffer[sizeof(struct cros_ec_command) +
735 sizeof(ec_dev->event_data.data)];
736 struct cros_ec_command *msg = (struct cros_ec_command *)&buffer;
737
738 msg->version = 0;
739 msg->command = EC_CMD_MKBP_STATE;
740 msg->insize = sizeof(ec_dev->event_data.data);
741 msg->outsize = 0;
742
743 ec_dev->event_size = cros_ec_cmd_xfer_status(ec_dev, msg);
744 ec_dev->event_data.event_type = EC_MKBP_EVENT_KEY_MATRIX;
745 memcpy(&ec_dev->event_data.data, msg->data,
746 sizeof(ec_dev->event_data.data));
747
748 return ec_dev->event_size;
749}
750
751/**
752 * cros_ec_get_next_event() - Fetch next event from the ChromeOS EC.
753 * @ec_dev: Device to fetch event from.
754 * @wake_event: Pointer to a bool set to true upon return if the event might be
755 * treated as a wake event. Ignored if null.
756 * @has_more_events: Pointer to bool set to true if more than one event is
757 * pending.
758 * Some EC will set this flag to indicate cros_ec_get_next_event()
759 * can be called multiple times in a row.
760 * It is an optimization to prevent issuing a EC command for
761 * nothing or wait for another interrupt from the EC to process
762 * the next message.
763 * Ignored if null.
764 *
765 * Return: negative error code on errors; 0 for no data; or else number of
766 * bytes received (i.e., an event was retrieved successfully). Event types are
767 * written out to @ec_dev->event_data.event_type on success.
768 */
769int cros_ec_get_next_event(struct cros_ec_device *ec_dev,
770 bool *wake_event,
771 bool *has_more_events)
772{
773 u8 event_type;
774 u32 host_event;
775 int ret;
776 u32 ver_mask;
777
778 /*
779 * Default value for wake_event.
780 * Wake up on keyboard event, wake up for spurious interrupt or link
781 * error to the EC.
782 */
783 if (wake_event)
784 *wake_event = true;
785
786 /*
787 * Default value for has_more_events.
788 * EC will raise another interrupt if AP does not process all events
789 * anyway.
790 */
791 if (has_more_events)
792 *has_more_events = false;
793
794 if (!ec_dev->mkbp_event_supported)
795 return get_keyboard_state_event(ec_dev);
796
797 ret = get_next_event(ec_dev);
798 /*
799 * -ENOPROTOOPT is returned when EC returns EC_RES_INVALID_VERSION.
800 * This can occur when EC based device (e.g. Fingerprint MCU) jumps to
801 * the RO image which doesn't support newer version of the command. In
802 * this case we will attempt to update maximum supported version of the
803 * EC_CMD_GET_NEXT_EVENT.
804 */
805 if (ret == -ENOPROTOOPT) {
806 dev_dbg(ec_dev->dev,
807 "GET_NEXT_EVENT returned invalid version error.\n");
808 ret = cros_ec_get_host_command_version_mask(ec_dev,
809 EC_CMD_GET_NEXT_EVENT,
810 &ver_mask);
811 if (ret < 0 || ver_mask == 0)
812 /*
813 * Do not change the MKBP supported version if we can't
814 * obtain supported version correctly. Please note that
815 * calling EC_CMD_GET_NEXT_EVENT returned
816 * EC_RES_INVALID_VERSION which means that the command
817 * is present.
818 */
819 return -ENOPROTOOPT;
820
821 ec_dev->mkbp_event_supported = fls(ver_mask);
822 dev_dbg(ec_dev->dev, "MKBP support version changed to %u\n",
823 ec_dev->mkbp_event_supported - 1);
824
825 /* Try to get next event with new MKBP support version set. */
826 ret = get_next_event(ec_dev);
827 }
828
829 if (ret <= 0)
830 return ret;
831
832 if (has_more_events)
833 *has_more_events = ec_dev->event_data.event_type &
834 EC_MKBP_HAS_MORE_EVENTS;
835 ec_dev->event_data.event_type &= EC_MKBP_EVENT_TYPE_MASK;
836
837 if (wake_event) {
838 event_type = ec_dev->event_data.event_type;
839 host_event = cros_ec_get_host_event(ec_dev);
840
841 /*
842 * Sensor events need to be parsed by the sensor sub-device.
843 * Defer them, and don't report the wakeup here.
844 */
845 if (event_type == EC_MKBP_EVENT_SENSOR_FIFO) {
846 *wake_event = false;
847 } else if (host_event) {
848 /* rtc_update_irq() already handles wakeup events. */
849 if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_RTC))
850 *wake_event = false;
851 /* Masked host-events should not count as wake events. */
852 if (!(host_event & ec_dev->host_event_wake_mask))
853 *wake_event = false;
854 }
855 }
856
857 return ret;
858}
859EXPORT_SYMBOL(cros_ec_get_next_event);
860
861/**
862 * cros_ec_get_host_event() - Return a mask of event set by the ChromeOS EC.
863 * @ec_dev: Device to fetch event from.
864 *
865 * When MKBP is supported, when the EC raises an interrupt, we collect the
866 * events raised and call the functions in the ec notifier. This function
867 * is a helper to know which events are raised.
868 *
869 * Return: 0 on error or non-zero bitmask of one or more EC_HOST_EVENT_*.
870 */
871u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev)
872{
873 u32 host_event;
874
875 if (!ec_dev->mkbp_event_supported)
876 return 0;
877
878 if (ec_dev->event_data.event_type != EC_MKBP_EVENT_HOST_EVENT)
879 return 0;
880
881 if (ec_dev->event_size != sizeof(host_event)) {
882 dev_warn(ec_dev->dev, "Invalid host event size\n");
883 return 0;
884 }
885
886 host_event = get_unaligned_le32(&ec_dev->event_data.data.host_event);
887
888 return host_event;
889}
890EXPORT_SYMBOL(cros_ec_get_host_event);
891
892/**
893 * cros_ec_check_features() - Test for the presence of EC features
894 *
895 * @ec: EC device, does not have to be connected directly to the AP,
896 * can be daisy chained through another device.
897 * @feature: One of ec_feature_code bit.
898 *
899 * Call this function to test whether the ChromeOS EC supports a feature.
900 *
901 * Return: true if supported, false if not (or if an error was encountered).
902 */
903bool cros_ec_check_features(struct cros_ec_dev *ec, int feature)
904{
905 struct ec_response_get_features *features = &ec->features;
906 int ret;
907
908 if (features->flags[0] == -1U && features->flags[1] == -1U) {
909 /* features bitmap not read yet */
910 ret = cros_ec_cmd(ec->ec_dev, 0, EC_CMD_GET_FEATURES + ec->cmd_offset,
911 NULL, 0, features, sizeof(*features));
912 if (ret < 0) {
913 dev_warn(ec->dev, "cannot get EC features: %d\n", ret);
914 memset(features, 0, sizeof(*features));
915 }
916
917 dev_dbg(ec->dev, "EC features %08x %08x\n",
918 features->flags[0], features->flags[1]);
919 }
920
921 return !!(features->flags[feature / 32] & EC_FEATURE_MASK_0(feature));
922}
923EXPORT_SYMBOL_GPL(cros_ec_check_features);
924
925/**
926 * cros_ec_get_sensor_count() - Return the number of MEMS sensors supported.
927 *
928 * @ec: EC device, does not have to be connected directly to the AP,
929 * can be daisy chained through another device.
930 * Return: < 0 in case of error.
931 */
932int cros_ec_get_sensor_count(struct cros_ec_dev *ec)
933{
934 /*
935 * Issue a command to get the number of sensor reported.
936 * If not supported, check for legacy mode.
937 */
938 int ret, sensor_count;
939 struct ec_params_motion_sense *params;
940 struct ec_response_motion_sense *resp;
941 struct cros_ec_command *msg;
942 struct cros_ec_device *ec_dev = ec->ec_dev;
943 u8 status;
944
945 msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)),
946 GFP_KERNEL);
947 if (!msg)
948 return -ENOMEM;
949
950 msg->version = 1;
951 msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
952 msg->outsize = sizeof(*params);
953 msg->insize = sizeof(*resp);
954
955 params = (struct ec_params_motion_sense *)msg->data;
956 params->cmd = MOTIONSENSE_CMD_DUMP;
957
958 ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
959 if (ret < 0) {
960 sensor_count = ret;
961 } else {
962 resp = (struct ec_response_motion_sense *)msg->data;
963 sensor_count = resp->dump.sensor_count;
964 }
965 kfree(msg);
966
967 /*
968 * Check legacy mode: Let's find out if sensors are accessible
969 * via LPC interface.
970 */
971 if (sensor_count < 0 && ec->cmd_offset == 0 && ec_dev->cmd_readmem) {
972 ret = ec_dev->cmd_readmem(ec_dev, EC_MEMMAP_ACC_STATUS,
973 1, &status);
974 if (ret >= 0 &&
975 (status & EC_MEMMAP_ACC_STATUS_PRESENCE_BIT)) {
976 /*
977 * We have 2 sensors, one in the lid, one in the base.
978 */
979 sensor_count = 2;
980 } else {
981 /*
982 * EC uses LPC interface and no sensors are presented.
983 */
984 sensor_count = 0;
985 }
986 }
987 return sensor_count;
988}
989EXPORT_SYMBOL_GPL(cros_ec_get_sensor_count);
990
991/**
992 * cros_ec_cmd - Send a command to the EC.
993 *
994 * @ec_dev: EC device
995 * @version: EC command version
996 * @command: EC command
997 * @outdata: EC command output data
998 * @outsize: Size of outdata
999 * @indata: EC command input data
1000 * @insize: Size of indata
1001 *
1002 * Return: >= 0 on success, negative error number on failure.
1003 */
1004int cros_ec_cmd(struct cros_ec_device *ec_dev,
1005 unsigned int version,
1006 int command,
1007 void *outdata,
1008 size_t outsize,
1009 void *indata,
1010 size_t insize)
1011{
1012 struct cros_ec_command *msg;
1013 int ret;
1014
1015 msg = kzalloc(sizeof(*msg) + max(insize, outsize), GFP_KERNEL);
1016 if (!msg)
1017 return -ENOMEM;
1018
1019 msg->version = version;
1020 msg->command = command;
1021 msg->outsize = outsize;
1022 msg->insize = insize;
1023
1024 if (outsize)
1025 memcpy(msg->data, outdata, outsize);
1026
1027 ret = cros_ec_cmd_xfer_status(ec_dev, msg);
1028 if (ret < 0)
1029 goto error;
1030
1031 if (insize)
1032 memcpy(indata, msg->data, insize);
1033error:
1034 kfree(msg);
1035 return ret;
1036}
1037EXPORT_SYMBOL_GPL(cros_ec_cmd);