xref: /linux/net/ethtool/cmis_cdb.c (revision 9410645520e9b820069761f3450ef6661418e279)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <linux/ethtool.h>
4 #include <linux/jiffies.h>
5 
6 #include "common.h"
7 #include "module_fw.h"
8 #include "cmis.h"
9 
10 /* For accessing the LPL field on page 9Fh, the allowable length extension is
11  * min(i, 15) byte octets where i specifies the allowable additional number of
12  * byte octets in a READ or a WRITE.
13  */
ethtool_cmis_get_max_payload_size(u8 num_of_byte_octs)14 u32 ethtool_cmis_get_max_payload_size(u8 num_of_byte_octs)
15 {
16 	return 8 * (1 + min_t(u8, num_of_byte_octs, 15));
17 }
18 
ethtool_cmis_cdb_compose_args(struct ethtool_cmis_cdb_cmd_args * args,enum ethtool_cmis_cdb_cmd_id cmd,u8 * pl,u8 lpl_len,u16 max_duration,u8 read_write_len_ext,u16 msleep_pre_rpl,u8 rpl_exp_len,u8 flags)19 void ethtool_cmis_cdb_compose_args(struct ethtool_cmis_cdb_cmd_args *args,
20 				   enum ethtool_cmis_cdb_cmd_id cmd, u8 *pl,
21 				   u8 lpl_len, u16 max_duration,
22 				   u8 read_write_len_ext, u16 msleep_pre_rpl,
23 				   u8 rpl_exp_len, u8 flags)
24 {
25 	args->req.id = cpu_to_be16(cmd);
26 	args->req.lpl_len = lpl_len;
27 	if (pl)
28 		memcpy(args->req.payload, pl, args->req.lpl_len);
29 
30 	args->max_duration = max_duration;
31 	args->read_write_len_ext =
32 		ethtool_cmis_get_max_payload_size(read_write_len_ext);
33 	args->msleep_pre_rpl = msleep_pre_rpl;
34 	args->rpl_exp_len = rpl_exp_len;
35 	args->flags = flags;
36 	args->err_msg = NULL;
37 }
38 
ethtool_cmis_page_init(struct ethtool_module_eeprom * page_data,u8 page,u32 offset,u32 length)39 void ethtool_cmis_page_init(struct ethtool_module_eeprom *page_data,
40 			    u8 page, u32 offset, u32 length)
41 {
42 	page_data->page = page;
43 	page_data->offset = offset;
44 	page_data->length = length;
45 	page_data->i2c_address = ETHTOOL_CMIS_CDB_PAGE_I2C_ADDR;
46 }
47 
48 #define CMIS_REVISION_PAGE	0x00
49 #define CMIS_REVISION_OFFSET	0x01
50 
51 struct cmis_rev_rpl {
52 	u8 rev;
53 };
54 
cmis_rev_rpl_major(struct cmis_rev_rpl * rpl)55 static u8 cmis_rev_rpl_major(struct cmis_rev_rpl *rpl)
56 {
57 	return rpl->rev >> 4;
58 }
59 
cmis_rev_major_get(struct net_device * dev,u8 * rev_major)60 static int cmis_rev_major_get(struct net_device *dev, u8 *rev_major)
61 {
62 	const struct ethtool_ops *ops = dev->ethtool_ops;
63 	struct ethtool_module_eeprom page_data = {0};
64 	struct netlink_ext_ack extack = {};
65 	struct cmis_rev_rpl rpl = {};
66 	int err;
67 
68 	ethtool_cmis_page_init(&page_data, CMIS_REVISION_PAGE,
69 			       CMIS_REVISION_OFFSET, sizeof(rpl));
70 	page_data.data = (u8 *)&rpl;
71 
72 	err = ops->get_module_eeprom_by_page(dev, &page_data, &extack);
73 	if (err < 0) {
74 		if (extack._msg)
75 			netdev_err(dev, "%s\n", extack._msg);
76 		return err;
77 	}
78 
79 	*rev_major = cmis_rev_rpl_major(&rpl);
80 
81 	return 0;
82 }
83 
84 #define CMIS_CDB_ADVERTISEMENT_PAGE	0x01
85 #define CMIS_CDB_ADVERTISEMENT_OFFSET	0xA3
86 
87 /* Based on section 8.4.11 "CDB Messaging Support Advertisement" in CMIS
88  * standard revision 5.2.
89  */
90 struct cmis_cdb_advert_rpl {
91 	u8	inst_supported;
92 	u8	read_write_len_ext;
93 	u8	resv1;
94 	u8	resv2;
95 };
96 
cmis_cdb_advert_rpl_inst_supported(struct cmis_cdb_advert_rpl * rpl)97 static u8 cmis_cdb_advert_rpl_inst_supported(struct cmis_cdb_advert_rpl *rpl)
98 {
99 	return rpl->inst_supported >> 6;
100 }
101 
cmis_cdb_advertisement_get(struct ethtool_cmis_cdb * cdb,struct net_device * dev,struct ethnl_module_fw_flash_ntf_params * ntf_params)102 static int cmis_cdb_advertisement_get(struct ethtool_cmis_cdb *cdb,
103 				      struct net_device *dev,
104 				      struct ethnl_module_fw_flash_ntf_params *ntf_params)
105 {
106 	const struct ethtool_ops *ops = dev->ethtool_ops;
107 	struct ethtool_module_eeprom page_data = {};
108 	struct cmis_cdb_advert_rpl rpl = {};
109 	struct netlink_ext_ack extack = {};
110 	int err;
111 
112 	ethtool_cmis_page_init(&page_data, CMIS_CDB_ADVERTISEMENT_PAGE,
113 			       CMIS_CDB_ADVERTISEMENT_OFFSET, sizeof(rpl));
114 	page_data.data = (u8 *)&rpl;
115 
116 	err = ops->get_module_eeprom_by_page(dev, &page_data, &extack);
117 	if (err < 0) {
118 		if (extack._msg)
119 			netdev_err(dev, "%s\n", extack._msg);
120 		return err;
121 	}
122 
123 	if (!cmis_cdb_advert_rpl_inst_supported(&rpl)) {
124 		ethnl_module_fw_flash_ntf_err(dev, ntf_params,
125 					      "CDB functionality is not supported",
126 					      NULL);
127 		return -EOPNOTSUPP;
128 	}
129 
130 	cdb->read_write_len_ext = rpl.read_write_len_ext;
131 
132 	return 0;
133 }
134 
135 #define CMIS_PASSWORD_ENTRY_PAGE	0x00
136 #define CMIS_PASSWORD_ENTRY_OFFSET	0x7A
137 
138 struct cmis_password_entry_pl {
139 	__be32 password;
140 };
141 
142 /* See section 9.3.1 "CMD 0000h: Query Status" in CMIS standard revision 5.2.
143  * struct cmis_cdb_query_status_pl and struct cmis_cdb_query_status_rpl are
144  * structured layouts of the flat arrays,
145  * struct ethtool_cmis_cdb_request::payload and
146  * struct ethtool_cmis_cdb_rpl::payload respectively.
147  */
148 struct cmis_cdb_query_status_pl {
149 	u16 response_delay;
150 };
151 
152 struct cmis_cdb_query_status_rpl {
153 	u8 length;
154 	u8 status;
155 };
156 
157 static int
cmis_cdb_validate_password(struct ethtool_cmis_cdb * cdb,struct net_device * dev,const struct ethtool_module_fw_flash_params * params,struct ethnl_module_fw_flash_ntf_params * ntf_params)158 cmis_cdb_validate_password(struct ethtool_cmis_cdb *cdb,
159 			   struct net_device *dev,
160 			   const struct ethtool_module_fw_flash_params *params,
161 			   struct ethnl_module_fw_flash_ntf_params *ntf_params)
162 {
163 	const struct ethtool_ops *ops = dev->ethtool_ops;
164 	struct cmis_cdb_query_status_pl qs_pl = {0};
165 	struct ethtool_module_eeprom page_data = {};
166 	struct ethtool_cmis_cdb_cmd_args args = {};
167 	struct cmis_password_entry_pl pe_pl = {};
168 	struct cmis_cdb_query_status_rpl *rpl;
169 	struct netlink_ext_ack extack = {};
170 	int err;
171 
172 	ethtool_cmis_page_init(&page_data, CMIS_PASSWORD_ENTRY_PAGE,
173 			       CMIS_PASSWORD_ENTRY_OFFSET, sizeof(pe_pl));
174 	page_data.data = (u8 *)&pe_pl;
175 
176 	pe_pl = *((struct cmis_password_entry_pl *)page_data.data);
177 	pe_pl.password = params->password;
178 	err = ops->set_module_eeprom_by_page(dev, &page_data, &extack);
179 	if (err < 0) {
180 		if (extack._msg)
181 			netdev_err(dev, "%s\n", extack._msg);
182 		return err;
183 	}
184 
185 	ethtool_cmis_cdb_compose_args(&args, ETHTOOL_CMIS_CDB_CMD_QUERY_STATUS,
186 				      (u8 *)&qs_pl, sizeof(qs_pl), 0,
187 				      cdb->read_write_len_ext, 1000,
188 				      sizeof(*rpl),
189 				      CDB_F_COMPLETION_VALID | CDB_F_STATUS_VALID);
190 
191 	err = ethtool_cmis_cdb_execute_cmd(dev, &args);
192 	if (err < 0) {
193 		ethnl_module_fw_flash_ntf_err(dev, ntf_params,
194 					      "Query Status command failed",
195 					      args.err_msg);
196 		return err;
197 	}
198 
199 	rpl = (struct cmis_cdb_query_status_rpl *)args.req.payload;
200 	if (!rpl->length || !rpl->status) {
201 		ethnl_module_fw_flash_ntf_err(dev, ntf_params,
202 					      "Password was not accepted",
203 					      NULL);
204 		return -EINVAL;
205 	}
206 
207 	return 0;
208 }
209 
210 /* Some CDB commands asserts the CDB completion flag only from CMIS
211  * revision 5. Therefore, check the relevant validity flag only when
212  * the revision supports it.
213  */
ethtool_cmis_cdb_check_completion_flag(u8 cmis_rev,u8 * flags)214 void ethtool_cmis_cdb_check_completion_flag(u8 cmis_rev, u8 *flags)
215 {
216 	*flags |= cmis_rev >= 5 ? CDB_F_COMPLETION_VALID : 0;
217 }
218 
219 #define CMIS_CDB_MODULE_FEATURES_RESV_DATA	34
220 
221 /* See section 9.4.1 "CMD 0040h: Module Features" in CMIS standard revision 5.2.
222  * struct cmis_cdb_module_features_rpl is structured layout of the flat
223  * array, ethtool_cmis_cdb_rpl::payload.
224  */
225 struct cmis_cdb_module_features_rpl {
226 	u8	resv1[CMIS_CDB_MODULE_FEATURES_RESV_DATA];
227 	__be16	max_completion_time;
228 };
229 
230 static u16
cmis_cdb_module_features_completion_time(struct cmis_cdb_module_features_rpl * rpl)231 cmis_cdb_module_features_completion_time(struct cmis_cdb_module_features_rpl *rpl)
232 {
233 	return be16_to_cpu(rpl->max_completion_time);
234 }
235 
cmis_cdb_module_features_get(struct ethtool_cmis_cdb * cdb,struct net_device * dev,struct ethnl_module_fw_flash_ntf_params * ntf_params)236 static int cmis_cdb_module_features_get(struct ethtool_cmis_cdb *cdb,
237 					struct net_device *dev,
238 					struct ethnl_module_fw_flash_ntf_params *ntf_params)
239 {
240 	struct ethtool_cmis_cdb_cmd_args args = {};
241 	struct cmis_cdb_module_features_rpl *rpl;
242 	u8 flags = CDB_F_STATUS_VALID;
243 	int err;
244 
245 	ethtool_cmis_cdb_check_completion_flag(cdb->cmis_rev, &flags);
246 	ethtool_cmis_cdb_compose_args(&args,
247 				      ETHTOOL_CMIS_CDB_CMD_MODULE_FEATURES,
248 				      NULL, 0, 0, cdb->read_write_len_ext,
249 				      1000, sizeof(*rpl), flags);
250 
251 	err = ethtool_cmis_cdb_execute_cmd(dev, &args);
252 	if (err < 0) {
253 		ethnl_module_fw_flash_ntf_err(dev, ntf_params,
254 					      "Module Features command failed",
255 					      args.err_msg);
256 		return err;
257 	}
258 
259 	rpl = (struct cmis_cdb_module_features_rpl *)args.req.payload;
260 	cdb->max_completion_time =
261 		cmis_cdb_module_features_completion_time(rpl);
262 
263 	return 0;
264 }
265 
266 struct ethtool_cmis_cdb *
ethtool_cmis_cdb_init(struct net_device * dev,const struct ethtool_module_fw_flash_params * params,struct ethnl_module_fw_flash_ntf_params * ntf_params)267 ethtool_cmis_cdb_init(struct net_device *dev,
268 		      const struct ethtool_module_fw_flash_params *params,
269 		      struct ethnl_module_fw_flash_ntf_params *ntf_params)
270 {
271 	struct ethtool_cmis_cdb *cdb;
272 	int err;
273 
274 	cdb = kzalloc(sizeof(*cdb), GFP_KERNEL);
275 	if (!cdb)
276 		return ERR_PTR(-ENOMEM);
277 
278 	err = cmis_rev_major_get(dev, &cdb->cmis_rev);
279 	if (err < 0)
280 		goto err;
281 
282 	if (cdb->cmis_rev < 4) {
283 		ethnl_module_fw_flash_ntf_err(dev, ntf_params,
284 					      "CMIS revision doesn't support module firmware flashing",
285 					      NULL);
286 		err = -EOPNOTSUPP;
287 		goto err;
288 	}
289 
290 	err = cmis_cdb_advertisement_get(cdb, dev, ntf_params);
291 	if (err < 0)
292 		goto err;
293 
294 	if (params->password_valid) {
295 		err = cmis_cdb_validate_password(cdb, dev, params, ntf_params);
296 		if (err < 0)
297 			goto err;
298 	}
299 
300 	err = cmis_cdb_module_features_get(cdb, dev, ntf_params);
301 	if (err < 0)
302 		goto err;
303 
304 	return cdb;
305 
306 err:
307 	ethtool_cmis_cdb_fini(cdb);
308 	return ERR_PTR(err);
309 }
310 
ethtool_cmis_cdb_fini(struct ethtool_cmis_cdb * cdb)311 void ethtool_cmis_cdb_fini(struct ethtool_cmis_cdb *cdb)
312 {
313 	kfree(cdb);
314 }
315 
is_completed(u8 data)316 static bool is_completed(u8 data)
317 {
318 	return !!(data & 0x40);
319 }
320 
321 #define CMIS_CDB_STATUS_SUCCESS	0x01
322 
status_success(u8 data)323 static bool status_success(u8 data)
324 {
325 	return data == CMIS_CDB_STATUS_SUCCESS;
326 }
327 
328 #define CMIS_CDB_STATUS_FAIL	0x40
329 
status_fail(u8 data)330 static bool status_fail(u8 data)
331 {
332 	return data & CMIS_CDB_STATUS_FAIL;
333 }
334 
335 struct cmis_wait_for_cond_rpl {
336 	u8 state;
337 };
338 
339 static int
ethtool_cmis_module_poll(struct net_device * dev,struct cmis_wait_for_cond_rpl * rpl,u32 offset,bool (* cond_success)(u8),bool (* cond_fail)(u8))340 ethtool_cmis_module_poll(struct net_device *dev,
341 			 struct cmis_wait_for_cond_rpl *rpl, u32 offset,
342 			 bool (*cond_success)(u8), bool (*cond_fail)(u8))
343 {
344 	const struct ethtool_ops *ops = dev->ethtool_ops;
345 	struct ethtool_module_eeprom page_data = {0};
346 	struct netlink_ext_ack extack = {};
347 	int err;
348 
349 	ethtool_cmis_page_init(&page_data, 0, offset, sizeof(rpl));
350 	page_data.data = (u8 *)rpl;
351 
352 	err = ops->get_module_eeprom_by_page(dev, &page_data, &extack);
353 	if (err < 0) {
354 		if (extack._msg)
355 			netdev_err_once(dev, "%s\n", extack._msg);
356 		return -EBUSY;
357 	}
358 
359 	if ((*cond_success)(rpl->state))
360 		return 0;
361 
362 	if (*cond_fail && (*cond_fail)(rpl->state))
363 		return -EIO;
364 
365 	return -EBUSY;
366 }
367 
ethtool_cmis_wait_for_cond(struct net_device * dev,u8 flags,u8 flag,u16 max_duration,u32 offset,bool (* cond_success)(u8),bool (* cond_fail)(u8),u8 * state)368 int ethtool_cmis_wait_for_cond(struct net_device *dev, u8 flags, u8 flag,
369 			       u16 max_duration, u32 offset,
370 			       bool (*cond_success)(u8), bool (*cond_fail)(u8),
371 			       u8 *state)
372 {
373 	struct cmis_wait_for_cond_rpl rpl = {};
374 	unsigned long end;
375 	int err;
376 
377 	if (!(flags & flag))
378 		return 0;
379 
380 	if (max_duration == 0)
381 		max_duration = U16_MAX;
382 
383 	end = jiffies + msecs_to_jiffies(max_duration);
384 	do {
385 		err = ethtool_cmis_module_poll(dev, &rpl, offset, cond_success,
386 					       cond_fail);
387 		if (err != -EBUSY)
388 			goto out;
389 
390 		msleep(20);
391 	} while (time_before(jiffies, end));
392 
393 	err = ethtool_cmis_module_poll(dev, &rpl, offset, cond_success,
394 				       cond_fail);
395 	if (err == -EBUSY)
396 		err = -ETIMEDOUT;
397 
398 out:
399 	*state = rpl.state;
400 	return err;
401 }
402 
403 #define CMIS_CDB_COMPLETION_FLAG_OFFSET	0x08
404 
cmis_cdb_wait_for_completion(struct net_device * dev,struct ethtool_cmis_cdb_cmd_args * args)405 static int cmis_cdb_wait_for_completion(struct net_device *dev,
406 					struct ethtool_cmis_cdb_cmd_args *args)
407 {
408 	u8 flag;
409 	int err;
410 
411 	/* Some vendors demand waiting time before checking completion flag
412 	 * in some CDB commands.
413 	 */
414 	msleep(args->msleep_pre_rpl);
415 
416 	err = ethtool_cmis_wait_for_cond(dev, args->flags,
417 					 CDB_F_COMPLETION_VALID,
418 					 args->max_duration,
419 					 CMIS_CDB_COMPLETION_FLAG_OFFSET,
420 					 is_completed, NULL, &flag);
421 	if (err < 0)
422 		args->err_msg = "Completion Flag did not set on time";
423 
424 	return err;
425 }
426 
427 #define CMIS_CDB_STATUS_OFFSET	0x25
428 
cmis_cdb_status_fail_msg_get(u8 status,char ** err_msg)429 static void cmis_cdb_status_fail_msg_get(u8 status, char **err_msg)
430 {
431 	switch (status) {
432 	case 0b10000001:
433 		*err_msg = "CDB Status is in progress: Busy capturing command";
434 		break;
435 	case 0b10000010:
436 		*err_msg =
437 			"CDB Status is in progress: Busy checking/validating command";
438 		break;
439 	case 0b10000011:
440 		*err_msg = "CDB Status is in progress: Busy executing";
441 		break;
442 	case 0b01000000:
443 		*err_msg = "CDB status failed: no specific failure";
444 		break;
445 	case 0b01000010:
446 		*err_msg =
447 			"CDB status failed: Parameter range error or parameter not supported";
448 		break;
449 	case 0b01000101:
450 		*err_msg = "CDB status failed: CdbChkCode error";
451 		break;
452 	case 0b01000110:
453 		*err_msg = "CDB status failed: Password error";
454 		break;
455 	default:
456 		*err_msg = "Unknown failure reason";
457 	}
458 };
459 
cmis_cdb_wait_for_status(struct net_device * dev,struct ethtool_cmis_cdb_cmd_args * args)460 static int cmis_cdb_wait_for_status(struct net_device *dev,
461 				    struct ethtool_cmis_cdb_cmd_args *args)
462 {
463 	u8 status;
464 	int err;
465 
466 	/* Some vendors demand waiting time before checking status in some
467 	 * CDB commands.
468 	 */
469 	msleep(args->msleep_pre_rpl);
470 
471 	err = ethtool_cmis_wait_for_cond(dev, args->flags, CDB_F_STATUS_VALID,
472 					 args->max_duration,
473 					 CMIS_CDB_STATUS_OFFSET,
474 					 status_success, status_fail, &status);
475 	if (err < 0 && !args->err_msg)
476 		cmis_cdb_status_fail_msg_get(status, &args->err_msg);
477 
478 	return err;
479 }
480 
481 #define CMIS_CDB_REPLY_OFFSET	0x86
482 
cmis_cdb_process_reply(struct net_device * dev,struct ethtool_module_eeprom * page_data,struct ethtool_cmis_cdb_cmd_args * args)483 static int cmis_cdb_process_reply(struct net_device *dev,
484 				  struct ethtool_module_eeprom *page_data,
485 				  struct ethtool_cmis_cdb_cmd_args *args)
486 {
487 	u8 rpl_hdr_len = sizeof(struct ethtool_cmis_cdb_rpl_hdr);
488 	u8 rpl_exp_len = args->rpl_exp_len + rpl_hdr_len;
489 	const struct ethtool_ops *ops = dev->ethtool_ops;
490 	struct netlink_ext_ack extack = {};
491 	struct ethtool_cmis_cdb_rpl *rpl;
492 	int err;
493 
494 	if (!args->rpl_exp_len)
495 		return 0;
496 
497 	ethtool_cmis_page_init(page_data, ETHTOOL_CMIS_CDB_CMD_PAGE,
498 			       CMIS_CDB_REPLY_OFFSET, rpl_exp_len);
499 	page_data->data = kmalloc(page_data->length, GFP_KERNEL);
500 	if (!page_data->data)
501 		return -ENOMEM;
502 
503 	err = ops->get_module_eeprom_by_page(dev, page_data, &extack);
504 	if (err < 0) {
505 		if (extack._msg)
506 			netdev_err(dev, "%s\n", extack._msg);
507 		goto out;
508 	}
509 
510 	rpl = (struct ethtool_cmis_cdb_rpl *)page_data->data;
511 	if ((args->rpl_exp_len > rpl->hdr.rpl_len + rpl_hdr_len) ||
512 	    !rpl->hdr.rpl_chk_code) {
513 		err = -EIO;
514 		goto out;
515 	}
516 
517 	args->req.lpl_len = rpl->hdr.rpl_len;
518 	memcpy(args->req.payload, rpl->payload, args->req.lpl_len);
519 
520 out:
521 	kfree(page_data->data);
522 	return err;
523 }
524 
525 static int
__ethtool_cmis_cdb_execute_cmd(struct net_device * dev,struct ethtool_module_eeprom * page_data,u8 page,u32 offset,u32 length,void * data)526 __ethtool_cmis_cdb_execute_cmd(struct net_device *dev,
527 			       struct ethtool_module_eeprom *page_data,
528 			       u8 page, u32 offset, u32 length, void *data)
529 {
530 	const struct ethtool_ops *ops = dev->ethtool_ops;
531 	struct netlink_ext_ack extack = {};
532 	int err;
533 
534 	ethtool_cmis_page_init(page_data, page, offset, length);
535 	page_data->data = kmemdup(data, page_data->length, GFP_KERNEL);
536 	if (!page_data->data)
537 		return -ENOMEM;
538 
539 	err = ops->set_module_eeprom_by_page(dev, page_data, &extack);
540 	if (err < 0) {
541 		if (extack._msg)
542 			netdev_err(dev, "%s\n", extack._msg);
543 	}
544 
545 	kfree(page_data->data);
546 	return err;
547 }
548 
cmis_cdb_calc_checksum(const void * data,size_t size)549 static u8 cmis_cdb_calc_checksum(const void *data, size_t size)
550 {
551 	const u8 *bytes = (const u8 *)data;
552 	u8 checksum = 0;
553 
554 	for (size_t i = 0; i < size; i++)
555 		checksum += bytes[i];
556 
557 	return ~checksum;
558 }
559 
560 #define CMIS_CDB_CMD_ID_OFFSET	0x80
561 
ethtool_cmis_cdb_execute_cmd(struct net_device * dev,struct ethtool_cmis_cdb_cmd_args * args)562 int ethtool_cmis_cdb_execute_cmd(struct net_device *dev,
563 				 struct ethtool_cmis_cdb_cmd_args *args)
564 {
565 	struct ethtool_module_eeprom page_data = {};
566 	u32 offset;
567 	int err;
568 
569 	args->req.chk_code =
570 		cmis_cdb_calc_checksum(&args->req, sizeof(args->req));
571 
572 	if (args->req.lpl_len > args->read_write_len_ext) {
573 		args->err_msg = "LPL length is longer than CDB read write length extension allows";
574 		return -EINVAL;
575 	}
576 
577 	/* According to the CMIS standard, there are two options to trigger the
578 	 * CDB commands. The default option is triggering the command by writing
579 	 * the CMDID bytes. Therefore, the command will be split to 2 calls:
580 	 * First, with everything except the CMDID field and then the CMDID
581 	 * field.
582 	 */
583 	offset = CMIS_CDB_CMD_ID_OFFSET +
584 		offsetof(struct ethtool_cmis_cdb_request, body);
585 	err = __ethtool_cmis_cdb_execute_cmd(dev, &page_data,
586 					     ETHTOOL_CMIS_CDB_CMD_PAGE, offset,
587 					     sizeof(args->req.body),
588 					     &args->req.body);
589 	if (err < 0)
590 		return err;
591 
592 	offset = CMIS_CDB_CMD_ID_OFFSET +
593 		offsetof(struct ethtool_cmis_cdb_request, id);
594 	err = __ethtool_cmis_cdb_execute_cmd(dev, &page_data,
595 					     ETHTOOL_CMIS_CDB_CMD_PAGE, offset,
596 					     sizeof(args->req.id),
597 					     &args->req.id);
598 	if (err < 0)
599 		return err;
600 
601 	err = cmis_cdb_wait_for_completion(dev, args);
602 	if (err < 0)
603 		return err;
604 
605 	err = cmis_cdb_wait_for_status(dev, args);
606 	if (err < 0)
607 		return err;
608 
609 	return cmis_cdb_process_reply(dev, &page_data, args);
610 }
611