xref: /openbmc/u-boot/drivers/misc/cros_ec.c (revision ad5b5801)
1 /*
2  * Chromium OS cros_ec driver
3  *
4  * Copyright (c) 2012 The Chromium OS Authors.
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 /*
10  * This is the interface to the Chrome OS EC. It provides keyboard functions,
11  * power control and battery management. Quite a few other functions are
12  * provided to enable the EC software to be updated, talk to the EC's I2C bus
13  * and store a small amount of data in a memory which persists while the EC
14  * is not reset.
15  */
16 
17 #include <common.h>
18 #include <command.h>
19 #include <dm.h>
20 #include <i2c.h>
21 #include <cros_ec.h>
22 #include <fdtdec.h>
23 #include <malloc.h>
24 #include <spi.h>
25 #include <asm/errno.h>
26 #include <asm/io.h>
27 #include <asm-generic/gpio.h>
28 #include <dm/device-internal.h>
29 #include <dm/root.h>
30 #include <dm/uclass-internal.h>
31 
32 #ifdef DEBUG_TRACE
33 #define debug_trace(fmt, b...)	debug(fmt, #b)
34 #else
35 #define debug_trace(fmt, b...)
36 #endif
37 
38 enum {
39 	/* Timeout waiting for a flash erase command to complete */
40 	CROS_EC_CMD_TIMEOUT_MS	= 5000,
41 	/* Timeout waiting for a synchronous hash to be recomputed */
42 	CROS_EC_CMD_HASH_TIMEOUT_MS = 2000,
43 };
44 
45 DECLARE_GLOBAL_DATA_PTR;
46 
47 /* Note: depends on enum ec_current_image */
48 static const char * const ec_current_image_name[] = {"unknown", "RO", "RW"};
49 
50 void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len)
51 {
52 #ifdef DEBUG
53 	int i;
54 
55 	printf("%s: ", name);
56 	if (cmd != -1)
57 		printf("cmd=%#x: ", cmd);
58 	for (i = 0; i < len; i++)
59 		printf("%02x ", data[i]);
60 	printf("\n");
61 #endif
62 }
63 
64 /*
65  * Calculate a simple 8-bit checksum of a data block
66  *
67  * @param data	Data block to checksum
68  * @param size	Size of data block in bytes
69  * @return checksum value (0 to 255)
70  */
71 int cros_ec_calc_checksum(const uint8_t *data, int size)
72 {
73 	int csum, i;
74 
75 	for (i = csum = 0; i < size; i++)
76 		csum += data[i];
77 	return csum & 0xff;
78 }
79 
80 /**
81  * Create a request packet for protocol version 3.
82  *
83  * The packet is stored in the device's internal output buffer.
84  *
85  * @param dev		CROS-EC device
86  * @param cmd		Command to send (EC_CMD_...)
87  * @param cmd_version	Version of command to send (EC_VER_...)
88  * @param dout          Output data (may be NULL If dout_len=0)
89  * @param dout_len      Size of output data in bytes
90  * @return packet size in bytes, or <0 if error.
91  */
92 static int create_proto3_request(struct cros_ec_dev *dev,
93 				 int cmd, int cmd_version,
94 				 const void *dout, int dout_len)
95 {
96 	struct ec_host_request *rq = (struct ec_host_request *)dev->dout;
97 	int out_bytes = dout_len + sizeof(*rq);
98 
99 	/* Fail if output size is too big */
100 	if (out_bytes > (int)sizeof(dev->dout)) {
101 		debug("%s: Cannot send %d bytes\n", __func__, dout_len);
102 		return -EC_RES_REQUEST_TRUNCATED;
103 	}
104 
105 	/* Fill in request packet */
106 	rq->struct_version = EC_HOST_REQUEST_VERSION;
107 	rq->checksum = 0;
108 	rq->command = cmd;
109 	rq->command_version = cmd_version;
110 	rq->reserved = 0;
111 	rq->data_len = dout_len;
112 
113 	/* Copy data after header */
114 	memcpy(rq + 1, dout, dout_len);
115 
116 	/* Write checksum field so the entire packet sums to 0 */
117 	rq->checksum = (uint8_t)(-cros_ec_calc_checksum(dev->dout, out_bytes));
118 
119 	cros_ec_dump_data("out", cmd, dev->dout, out_bytes);
120 
121 	/* Return size of request packet */
122 	return out_bytes;
123 }
124 
125 /**
126  * Prepare the device to receive a protocol version 3 response.
127  *
128  * @param dev		CROS-EC device
129  * @param din_len       Maximum size of response in bytes
130  * @return maximum expected number of bytes in response, or <0 if error.
131  */
132 static int prepare_proto3_response_buffer(struct cros_ec_dev *dev, int din_len)
133 {
134 	int in_bytes = din_len + sizeof(struct ec_host_response);
135 
136 	/* Fail if input size is too big */
137 	if (in_bytes > (int)sizeof(dev->din)) {
138 		debug("%s: Cannot receive %d bytes\n", __func__, din_len);
139 		return -EC_RES_RESPONSE_TOO_BIG;
140 	}
141 
142 	/* Return expected size of response packet */
143 	return in_bytes;
144 }
145 
146 /**
147  * Handle a protocol version 3 response packet.
148  *
149  * The packet must already be stored in the device's internal input buffer.
150  *
151  * @param dev		CROS-EC device
152  * @param dinp          Returns pointer to response data
153  * @param din_len       Maximum size of response in bytes
154  * @return number of bytes of response data, or <0 if error. Note that error
155  * codes can be from errno.h or -ve EC_RES_INVALID_CHECKSUM values (and they
156  * overlap!)
157  */
158 static int handle_proto3_response(struct cros_ec_dev *dev,
159 				  uint8_t **dinp, int din_len)
160 {
161 	struct ec_host_response *rs = (struct ec_host_response *)dev->din;
162 	int in_bytes;
163 	int csum;
164 
165 	cros_ec_dump_data("in-header", -1, dev->din, sizeof(*rs));
166 
167 	/* Check input data */
168 	if (rs->struct_version != EC_HOST_RESPONSE_VERSION) {
169 		debug("%s: EC response version mismatch\n", __func__);
170 		return -EC_RES_INVALID_RESPONSE;
171 	}
172 
173 	if (rs->reserved) {
174 		debug("%s: EC response reserved != 0\n", __func__);
175 		return -EC_RES_INVALID_RESPONSE;
176 	}
177 
178 	if (rs->data_len > din_len) {
179 		debug("%s: EC returned too much data\n", __func__);
180 		return -EC_RES_RESPONSE_TOO_BIG;
181 	}
182 
183 	cros_ec_dump_data("in-data", -1, dev->din + sizeof(*rs), rs->data_len);
184 
185 	/* Update in_bytes to actual data size */
186 	in_bytes = sizeof(*rs) + rs->data_len;
187 
188 	/* Verify checksum */
189 	csum = cros_ec_calc_checksum(dev->din, in_bytes);
190 	if (csum) {
191 		debug("%s: EC response checksum invalid: 0x%02x\n", __func__,
192 		      csum);
193 		return -EC_RES_INVALID_CHECKSUM;
194 	}
195 
196 	/* Return error result, if any */
197 	if (rs->result)
198 		return -(int)rs->result;
199 
200 	/* If we're still here, set response data pointer and return length */
201 	*dinp = (uint8_t *)(rs + 1);
202 
203 	return rs->data_len;
204 }
205 
206 static int send_command_proto3(struct cros_ec_dev *dev,
207 			       int cmd, int cmd_version,
208 			       const void *dout, int dout_len,
209 			       uint8_t **dinp, int din_len)
210 {
211 	struct dm_cros_ec_ops *ops;
212 	int out_bytes, in_bytes;
213 	int rv;
214 
215 	/* Create request packet */
216 	out_bytes = create_proto3_request(dev, cmd, cmd_version,
217 					  dout, dout_len);
218 	if (out_bytes < 0)
219 		return out_bytes;
220 
221 	/* Prepare response buffer */
222 	in_bytes = prepare_proto3_response_buffer(dev, din_len);
223 	if (in_bytes < 0)
224 		return in_bytes;
225 
226 	ops = dm_cros_ec_get_ops(dev->dev);
227 	rv = ops->packet ? ops->packet(dev->dev, out_bytes, in_bytes) : -ENOSYS;
228 	if (rv < 0)
229 		return rv;
230 
231 	/* Process the response */
232 	return handle_proto3_response(dev, dinp, din_len);
233 }
234 
235 static int send_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
236 			const void *dout, int dout_len,
237 			uint8_t **dinp, int din_len)
238 {
239 	struct dm_cros_ec_ops *ops;
240 	int ret = -1;
241 
242 	/* Handle protocol version 3 support */
243 	if (dev->protocol_version == 3) {
244 		return send_command_proto3(dev, cmd, cmd_version,
245 					   dout, dout_len, dinp, din_len);
246 	}
247 
248 	ops = dm_cros_ec_get_ops(dev->dev);
249 	ret = ops->command(dev->dev, cmd, cmd_version,
250 			   (const uint8_t *)dout, dout_len, dinp, din_len);
251 
252 	return ret;
253 }
254 
255 /**
256  * Send a command to the CROS-EC device and return the reply.
257  *
258  * The device's internal input/output buffers are used.
259  *
260  * @param dev		CROS-EC device
261  * @param cmd		Command to send (EC_CMD_...)
262  * @param cmd_version	Version of command to send (EC_VER_...)
263  * @param dout          Output data (may be NULL If dout_len=0)
264  * @param dout_len      Size of output data in bytes
265  * @param dinp          Response data (may be NULL If din_len=0).
266  *			If not NULL, it will be updated to point to the data
267  *			and will always be double word aligned (64-bits)
268  * @param din_len       Maximum size of response in bytes
269  * @return number of bytes in response, or -ve on error
270  */
271 static int ec_command_inptr(struct cros_ec_dev *dev, uint8_t cmd,
272 		int cmd_version, const void *dout, int dout_len, uint8_t **dinp,
273 		int din_len)
274 {
275 	uint8_t *din = NULL;
276 	int len;
277 
278 	len = send_command(dev, cmd, cmd_version, dout, dout_len,
279 				&din, din_len);
280 
281 	/* If the command doesn't complete, wait a while */
282 	if (len == -EC_RES_IN_PROGRESS) {
283 		struct ec_response_get_comms_status *resp = NULL;
284 		ulong start;
285 
286 		/* Wait for command to complete */
287 		start = get_timer(0);
288 		do {
289 			int ret;
290 
291 			mdelay(50);	/* Insert some reasonable delay */
292 			ret = send_command(dev, EC_CMD_GET_COMMS_STATUS, 0,
293 					NULL, 0,
294 					(uint8_t **)&resp, sizeof(*resp));
295 			if (ret < 0)
296 				return ret;
297 
298 			if (get_timer(start) > CROS_EC_CMD_TIMEOUT_MS) {
299 				debug("%s: Command %#02x timeout\n",
300 				      __func__, cmd);
301 				return -EC_RES_TIMEOUT;
302 			}
303 		} while (resp->flags & EC_COMMS_STATUS_PROCESSING);
304 
305 		/* OK it completed, so read the status response */
306 		/* not sure why it was 0 for the last argument */
307 		len = send_command(dev, EC_CMD_RESEND_RESPONSE, 0,
308 				NULL, 0, &din, din_len);
309 	}
310 
311 	debug("%s: len=%d, dinp=%p, *dinp=%p\n", __func__, len, dinp,
312 	      dinp ? *dinp : NULL);
313 	if (dinp) {
314 		/* If we have any data to return, it must be 64bit-aligned */
315 		assert(len <= 0 || !((uintptr_t)din & 7));
316 		*dinp = din;
317 	}
318 
319 	return len;
320 }
321 
322 /**
323  * Send a command to the CROS-EC device and return the reply.
324  *
325  * The device's internal input/output buffers are used.
326  *
327  * @param dev		CROS-EC device
328  * @param cmd		Command to send (EC_CMD_...)
329  * @param cmd_version	Version of command to send (EC_VER_...)
330  * @param dout          Output data (may be NULL If dout_len=0)
331  * @param dout_len      Size of output data in bytes
332  * @param din           Response data (may be NULL If din_len=0).
333  *			It not NULL, it is a place for ec_command() to copy the
334  *      data to.
335  * @param din_len       Maximum size of response in bytes
336  * @return number of bytes in response, or -ve on error
337  */
338 static int ec_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
339 		      const void *dout, int dout_len,
340 		      void *din, int din_len)
341 {
342 	uint8_t *in_buffer;
343 	int len;
344 
345 	assert((din_len == 0) || din);
346 	len = ec_command_inptr(dev, cmd, cmd_version, dout, dout_len,
347 			&in_buffer, din_len);
348 	if (len > 0) {
349 		/*
350 		 * If we were asked to put it somewhere, do so, otherwise just
351 		 * disregard the result.
352 		 */
353 		if (din && in_buffer) {
354 			assert(len <= din_len);
355 			memmove(din, in_buffer, len);
356 		}
357 	}
358 	return len;
359 }
360 
361 int cros_ec_scan_keyboard(struct udevice *dev, struct mbkp_keyscan *scan)
362 {
363 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
364 
365 	if (ec_command(cdev, EC_CMD_MKBP_STATE, 0, NULL, 0, scan,
366 		       sizeof(scan->data)) != sizeof(scan->data))
367 		return -1;
368 
369 	return 0;
370 }
371 
372 int cros_ec_read_id(struct cros_ec_dev *dev, char *id, int maxlen)
373 {
374 	struct ec_response_get_version *r;
375 
376 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
377 			(uint8_t **)&r, sizeof(*r)) != sizeof(*r))
378 		return -1;
379 
380 	if (maxlen > (int)sizeof(r->version_string_ro))
381 		maxlen = sizeof(r->version_string_ro);
382 
383 	switch (r->current_image) {
384 	case EC_IMAGE_RO:
385 		memcpy(id, r->version_string_ro, maxlen);
386 		break;
387 	case EC_IMAGE_RW:
388 		memcpy(id, r->version_string_rw, maxlen);
389 		break;
390 	default:
391 		return -1;
392 	}
393 
394 	id[maxlen - 1] = '\0';
395 	return 0;
396 }
397 
398 int cros_ec_read_version(struct cros_ec_dev *dev,
399 		       struct ec_response_get_version **versionp)
400 {
401 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
402 			(uint8_t **)versionp, sizeof(**versionp))
403 			!= sizeof(**versionp))
404 		return -1;
405 
406 	return 0;
407 }
408 
409 int cros_ec_read_build_info(struct cros_ec_dev *dev, char **strp)
410 {
411 	if (ec_command_inptr(dev, EC_CMD_GET_BUILD_INFO, 0, NULL, 0,
412 			(uint8_t **)strp, EC_PROTO2_MAX_PARAM_SIZE) < 0)
413 		return -1;
414 
415 	return 0;
416 }
417 
418 int cros_ec_read_current_image(struct cros_ec_dev *dev,
419 		enum ec_current_image *image)
420 {
421 	struct ec_response_get_version *r;
422 
423 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
424 			(uint8_t **)&r, sizeof(*r)) != sizeof(*r))
425 		return -1;
426 
427 	*image = r->current_image;
428 	return 0;
429 }
430 
431 static int cros_ec_wait_on_hash_done(struct cros_ec_dev *dev,
432 				  struct ec_response_vboot_hash *hash)
433 {
434 	struct ec_params_vboot_hash p;
435 	ulong start;
436 
437 	start = get_timer(0);
438 	while (hash->status == EC_VBOOT_HASH_STATUS_BUSY) {
439 		mdelay(50);	/* Insert some reasonable delay */
440 
441 		p.cmd = EC_VBOOT_HASH_GET;
442 		if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
443 		       hash, sizeof(*hash)) < 0)
444 			return -1;
445 
446 		if (get_timer(start) > CROS_EC_CMD_HASH_TIMEOUT_MS) {
447 			debug("%s: EC_VBOOT_HASH_GET timeout\n", __func__);
448 			return -EC_RES_TIMEOUT;
449 		}
450 	}
451 	return 0;
452 }
453 
454 
455 int cros_ec_read_hash(struct cros_ec_dev *dev,
456 		struct ec_response_vboot_hash *hash)
457 {
458 	struct ec_params_vboot_hash p;
459 	int rv;
460 
461 	p.cmd = EC_VBOOT_HASH_GET;
462 	if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
463 		       hash, sizeof(*hash)) < 0)
464 		return -1;
465 
466 	/* If the EC is busy calculating the hash, fidget until it's done. */
467 	rv = cros_ec_wait_on_hash_done(dev, hash);
468 	if (rv)
469 		return rv;
470 
471 	/* If the hash is valid, we're done. Otherwise, we have to kick it off
472 	 * again and wait for it to complete. Note that we explicitly assume
473 	 * that hashing zero bytes is always wrong, even though that would
474 	 * produce a valid hash value. */
475 	if (hash->status == EC_VBOOT_HASH_STATUS_DONE && hash->size)
476 		return 0;
477 
478 	debug("%s: No valid hash (status=%d size=%d). Compute one...\n",
479 	      __func__, hash->status, hash->size);
480 
481 	p.cmd = EC_VBOOT_HASH_START;
482 	p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
483 	p.nonce_size = 0;
484 	p.offset = EC_VBOOT_HASH_OFFSET_RW;
485 
486 	if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
487 		       hash, sizeof(*hash)) < 0)
488 		return -1;
489 
490 	rv = cros_ec_wait_on_hash_done(dev, hash);
491 	if (rv)
492 		return rv;
493 
494 	debug("%s: hash done\n", __func__);
495 
496 	return 0;
497 }
498 
499 static int cros_ec_invalidate_hash(struct cros_ec_dev *dev)
500 {
501 	struct ec_params_vboot_hash p;
502 	struct ec_response_vboot_hash *hash;
503 
504 	/* We don't have an explict command for the EC to discard its current
505 	 * hash value, so we'll just tell it to calculate one that we know is
506 	 * wrong (we claim that hashing zero bytes is always invalid).
507 	 */
508 	p.cmd = EC_VBOOT_HASH_RECALC;
509 	p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
510 	p.nonce_size = 0;
511 	p.offset = 0;
512 	p.size = 0;
513 
514 	debug("%s:\n", __func__);
515 
516 	if (ec_command_inptr(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
517 		       (uint8_t **)&hash, sizeof(*hash)) < 0)
518 		return -1;
519 
520 	/* No need to wait for it to finish */
521 	return 0;
522 }
523 
524 int cros_ec_reboot(struct cros_ec_dev *dev, enum ec_reboot_cmd cmd,
525 		uint8_t flags)
526 {
527 	struct ec_params_reboot_ec p;
528 
529 	p.cmd = cmd;
530 	p.flags = flags;
531 
532 	if (ec_command_inptr(dev, EC_CMD_REBOOT_EC, 0, &p, sizeof(p), NULL, 0)
533 			< 0)
534 		return -1;
535 
536 	if (!(flags & EC_REBOOT_FLAG_ON_AP_SHUTDOWN)) {
537 		/*
538 		 * EC reboot will take place immediately so delay to allow it
539 		 * to complete.  Note that some reboot types (EC_REBOOT_COLD)
540 		 * will reboot the AP as well, in which case we won't actually
541 		 * get to this point.
542 		 */
543 		/*
544 		 * TODO(rspangler@chromium.org): Would be nice if we had a
545 		 * better way to determine when the reboot is complete.  Could
546 		 * we poll a memory-mapped LPC value?
547 		 */
548 		udelay(50000);
549 	}
550 
551 	return 0;
552 }
553 
554 int cros_ec_interrupt_pending(struct udevice *dev)
555 {
556 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
557 
558 	/* no interrupt support : always poll */
559 	if (!dm_gpio_is_valid(&cdev->ec_int))
560 		return -ENOENT;
561 
562 	return dm_gpio_get_value(&cdev->ec_int);
563 }
564 
565 int cros_ec_info(struct cros_ec_dev *dev, struct ec_response_mkbp_info *info)
566 {
567 	if (ec_command(dev, EC_CMD_MKBP_INFO, 0, NULL, 0, info,
568 		       sizeof(*info)) != sizeof(*info))
569 		return -1;
570 
571 	return 0;
572 }
573 
574 int cros_ec_get_host_events(struct cros_ec_dev *dev, uint32_t *events_ptr)
575 {
576 	struct ec_response_host_event_mask *resp;
577 
578 	/*
579 	 * Use the B copy of the event flags, because the main copy is already
580 	 * used by ACPI/SMI.
581 	 */
582 	if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_GET_B, 0, NULL, 0,
583 		       (uint8_t **)&resp, sizeof(*resp)) < (int)sizeof(*resp))
584 		return -1;
585 
586 	if (resp->mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INVALID))
587 		return -1;
588 
589 	*events_ptr = resp->mask;
590 	return 0;
591 }
592 
593 int cros_ec_clear_host_events(struct cros_ec_dev *dev, uint32_t events)
594 {
595 	struct ec_params_host_event_mask params;
596 
597 	params.mask = events;
598 
599 	/*
600 	 * Use the B copy of the event flags, so it affects the data returned
601 	 * by cros_ec_get_host_events().
602 	 */
603 	if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_CLEAR_B, 0,
604 		       &params, sizeof(params), NULL, 0) < 0)
605 		return -1;
606 
607 	return 0;
608 }
609 
610 int cros_ec_flash_protect(struct cros_ec_dev *dev,
611 		       uint32_t set_mask, uint32_t set_flags,
612 		       struct ec_response_flash_protect *resp)
613 {
614 	struct ec_params_flash_protect params;
615 
616 	params.mask = set_mask;
617 	params.flags = set_flags;
618 
619 	if (ec_command(dev, EC_CMD_FLASH_PROTECT, EC_VER_FLASH_PROTECT,
620 		       &params, sizeof(params),
621 		       resp, sizeof(*resp)) != sizeof(*resp))
622 		return -1;
623 
624 	return 0;
625 }
626 
627 static int cros_ec_check_version(struct cros_ec_dev *dev)
628 {
629 	struct ec_params_hello req;
630 	struct ec_response_hello *resp;
631 
632 	struct dm_cros_ec_ops *ops;
633 	int ret;
634 
635 	ops = dm_cros_ec_get_ops(dev->dev);
636 	if (ops->check_version) {
637 		ret = ops->check_version(dev->dev);
638 		if (ret)
639 			return ret;
640 	}
641 
642 	/*
643 	 * TODO(sjg@chromium.org).
644 	 * There is a strange oddity here with the EC. We could just ignore
645 	 * the response, i.e. pass the last two parameters as NULL and 0.
646 	 * In this case we won't read back very many bytes from the EC.
647 	 * On the I2C bus the EC gets upset about this and will try to send
648 	 * the bytes anyway. This means that we will have to wait for that
649 	 * to complete before continuing with a new EC command.
650 	 *
651 	 * This problem is probably unique to the I2C bus.
652 	 *
653 	 * So for now, just read all the data anyway.
654 	 */
655 
656 	/* Try sending a version 3 packet */
657 	dev->protocol_version = 3;
658 	req.in_data = 0;
659 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
660 			     (uint8_t **)&resp, sizeof(*resp)) > 0) {
661 		return 0;
662 	}
663 
664 	/* Try sending a version 2 packet */
665 	dev->protocol_version = 2;
666 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
667 		       (uint8_t **)&resp, sizeof(*resp)) > 0) {
668 		return 0;
669 	}
670 
671 	/*
672 	 * Fail if we're still here, since the EC doesn't understand any
673 	 * protcol version we speak.  Version 1 interface without command
674 	 * version is no longer supported, and we don't know about any new
675 	 * protocol versions.
676 	 */
677 	dev->protocol_version = 0;
678 	printf("%s: ERROR: old EC interface not supported\n", __func__);
679 	return -1;
680 }
681 
682 int cros_ec_test(struct cros_ec_dev *dev)
683 {
684 	struct ec_params_hello req;
685 	struct ec_response_hello *resp;
686 
687 	req.in_data = 0x12345678;
688 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
689 		       (uint8_t **)&resp, sizeof(*resp)) < sizeof(*resp)) {
690 		printf("ec_command_inptr() returned error\n");
691 		return -1;
692 	}
693 	if (resp->out_data != req.in_data + 0x01020304) {
694 		printf("Received invalid handshake %x\n", resp->out_data);
695 		return -1;
696 	}
697 
698 	return 0;
699 }
700 
701 int cros_ec_flash_offset(struct cros_ec_dev *dev, enum ec_flash_region region,
702 		      uint32_t *offset, uint32_t *size)
703 {
704 	struct ec_params_flash_region_info p;
705 	struct ec_response_flash_region_info *r;
706 	int ret;
707 
708 	p.region = region;
709 	ret = ec_command_inptr(dev, EC_CMD_FLASH_REGION_INFO,
710 			 EC_VER_FLASH_REGION_INFO,
711 			 &p, sizeof(p), (uint8_t **)&r, sizeof(*r));
712 	if (ret != sizeof(*r))
713 		return -1;
714 
715 	if (offset)
716 		*offset = r->offset;
717 	if (size)
718 		*size = r->size;
719 
720 	return 0;
721 }
722 
723 int cros_ec_flash_erase(struct cros_ec_dev *dev, uint32_t offset, uint32_t size)
724 {
725 	struct ec_params_flash_erase p;
726 
727 	p.offset = offset;
728 	p.size = size;
729 	return ec_command_inptr(dev, EC_CMD_FLASH_ERASE, 0, &p, sizeof(p),
730 			NULL, 0);
731 }
732 
733 /**
734  * Write a single block to the flash
735  *
736  * Write a block of data to the EC flash. The size must not exceed the flash
737  * write block size which you can obtain from cros_ec_flash_write_burst_size().
738  *
739  * The offset starts at 0. You can obtain the region information from
740  * cros_ec_flash_offset() to find out where to write for a particular region.
741  *
742  * Attempting to write to the region where the EC is currently running from
743  * will result in an error.
744  *
745  * @param dev		CROS-EC device
746  * @param data		Pointer to data buffer to write
747  * @param offset	Offset within flash to write to.
748  * @param size		Number of bytes to write
749  * @return 0 if ok, -1 on error
750  */
751 static int cros_ec_flash_write_block(struct cros_ec_dev *dev,
752 		const uint8_t *data, uint32_t offset, uint32_t size)
753 {
754 	struct ec_params_flash_write p;
755 
756 	p.offset = offset;
757 	p.size = size;
758 	assert(data && p.size <= EC_FLASH_WRITE_VER0_SIZE);
759 	memcpy(&p + 1, data, p.size);
760 
761 	return ec_command_inptr(dev, EC_CMD_FLASH_WRITE, 0,
762 			  &p, sizeof(p), NULL, 0) >= 0 ? 0 : -1;
763 }
764 
765 /**
766  * Return optimal flash write burst size
767  */
768 static int cros_ec_flash_write_burst_size(struct cros_ec_dev *dev)
769 {
770 	return EC_FLASH_WRITE_VER0_SIZE;
771 }
772 
773 /**
774  * Check if a block of data is erased (all 0xff)
775  *
776  * This function is useful when dealing with flash, for checking whether a
777  * data block is erased and thus does not need to be programmed.
778  *
779  * @param data		Pointer to data to check (must be word-aligned)
780  * @param size		Number of bytes to check (must be word-aligned)
781  * @return 0 if erased, non-zero if any word is not erased
782  */
783 static int cros_ec_data_is_erased(const uint32_t *data, int size)
784 {
785 	assert(!(size & 3));
786 	size /= sizeof(uint32_t);
787 	for (; size > 0; size -= 4, data++)
788 		if (*data != -1U)
789 			return 0;
790 
791 	return 1;
792 }
793 
794 int cros_ec_flash_write(struct cros_ec_dev *dev, const uint8_t *data,
795 		     uint32_t offset, uint32_t size)
796 {
797 	uint32_t burst = cros_ec_flash_write_burst_size(dev);
798 	uint32_t end, off;
799 	int ret;
800 
801 	/*
802 	 * TODO: round up to the nearest multiple of write size.  Can get away
803 	 * without that on link right now because its write size is 4 bytes.
804 	 */
805 	end = offset + size;
806 	for (off = offset; off < end; off += burst, data += burst) {
807 		uint32_t todo;
808 
809 		/* If the data is empty, there is no point in programming it */
810 		todo = min(end - off, burst);
811 		if (dev->optimise_flash_write &&
812 				cros_ec_data_is_erased((uint32_t *)data, todo))
813 			continue;
814 
815 		ret = cros_ec_flash_write_block(dev, data, off, todo);
816 		if (ret)
817 			return ret;
818 	}
819 
820 	return 0;
821 }
822 
823 /**
824  * Read a single block from the flash
825  *
826  * Read a block of data from the EC flash. The size must not exceed the flash
827  * write block size which you can obtain from cros_ec_flash_write_burst_size().
828  *
829  * The offset starts at 0. You can obtain the region information from
830  * cros_ec_flash_offset() to find out where to read for a particular region.
831  *
832  * @param dev		CROS-EC device
833  * @param data		Pointer to data buffer to read into
834  * @param offset	Offset within flash to read from
835  * @param size		Number of bytes to read
836  * @return 0 if ok, -1 on error
837  */
838 static int cros_ec_flash_read_block(struct cros_ec_dev *dev, uint8_t *data,
839 				 uint32_t offset, uint32_t size)
840 {
841 	struct ec_params_flash_read p;
842 
843 	p.offset = offset;
844 	p.size = size;
845 
846 	return ec_command(dev, EC_CMD_FLASH_READ, 0,
847 			  &p, sizeof(p), data, size) >= 0 ? 0 : -1;
848 }
849 
850 int cros_ec_flash_read(struct cros_ec_dev *dev, uint8_t *data, uint32_t offset,
851 		    uint32_t size)
852 {
853 	uint32_t burst = cros_ec_flash_write_burst_size(dev);
854 	uint32_t end, off;
855 	int ret;
856 
857 	end = offset + size;
858 	for (off = offset; off < end; off += burst, data += burst) {
859 		ret = cros_ec_flash_read_block(dev, data, off,
860 					    min(end - off, burst));
861 		if (ret)
862 			return ret;
863 	}
864 
865 	return 0;
866 }
867 
868 int cros_ec_flash_update_rw(struct cros_ec_dev *dev,
869 			 const uint8_t *image, int image_size)
870 {
871 	uint32_t rw_offset, rw_size;
872 	int ret;
873 
874 	if (cros_ec_flash_offset(dev, EC_FLASH_REGION_RW, &rw_offset, &rw_size))
875 		return -1;
876 	if (image_size > (int)rw_size)
877 		return -1;
878 
879 	/* Invalidate the existing hash, just in case the AP reboots
880 	 * unexpectedly during the update. If that happened, the EC RW firmware
881 	 * would be invalid, but the EC would still have the original hash.
882 	 */
883 	ret = cros_ec_invalidate_hash(dev);
884 	if (ret)
885 		return ret;
886 
887 	/*
888 	 * Erase the entire RW section, so that the EC doesn't see any garbage
889 	 * past the new image if it's smaller than the current image.
890 	 *
891 	 * TODO: could optimize this to erase just the current image, since
892 	 * presumably everything past that is 0xff's.  But would still need to
893 	 * round up to the nearest multiple of erase size.
894 	 */
895 	ret = cros_ec_flash_erase(dev, rw_offset, rw_size);
896 	if (ret)
897 		return ret;
898 
899 	/* Write the image */
900 	ret = cros_ec_flash_write(dev, image, rw_offset, image_size);
901 	if (ret)
902 		return ret;
903 
904 	return 0;
905 }
906 
907 int cros_ec_read_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block)
908 {
909 	struct ec_params_vbnvcontext p;
910 	int len;
911 
912 	p.op = EC_VBNV_CONTEXT_OP_READ;
913 
914 	len = ec_command(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
915 			&p, sizeof(p), block, EC_VBNV_BLOCK_SIZE);
916 	if (len < EC_VBNV_BLOCK_SIZE)
917 		return -1;
918 
919 	return 0;
920 }
921 
922 int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block)
923 {
924 	struct ec_params_vbnvcontext p;
925 	int len;
926 
927 	p.op = EC_VBNV_CONTEXT_OP_WRITE;
928 	memcpy(p.block, block, sizeof(p.block));
929 
930 	len = ec_command_inptr(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
931 			&p, sizeof(p), NULL, 0);
932 	if (len < 0)
933 		return -1;
934 
935 	return 0;
936 }
937 
938 int cros_ec_set_ldo(struct udevice *dev, uint8_t index, uint8_t state)
939 {
940 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
941 	struct ec_params_ldo_set params;
942 
943 	params.index = index;
944 	params.state = state;
945 
946 	if (ec_command_inptr(cdev, EC_CMD_LDO_SET, 0, &params, sizeof(params),
947 			     NULL, 0))
948 		return -1;
949 
950 	return 0;
951 }
952 
953 int cros_ec_get_ldo(struct udevice *dev, uint8_t index, uint8_t *state)
954 {
955 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
956 	struct ec_params_ldo_get params;
957 	struct ec_response_ldo_get *resp;
958 
959 	params.index = index;
960 
961 	if (ec_command_inptr(cdev, EC_CMD_LDO_GET, 0, &params, sizeof(params),
962 			     (uint8_t **)&resp, sizeof(*resp)) !=
963 			     sizeof(*resp))
964 		return -1;
965 
966 	*state = resp->state;
967 
968 	return 0;
969 }
970 
971 int cros_ec_register(struct udevice *dev)
972 {
973 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
974 	const void *blob = gd->fdt_blob;
975 	int node = dev->of_offset;
976 	char id[MSG_BYTES];
977 
978 	cdev->dev = dev;
979 	gpio_request_by_name(dev, "ec-interrupt", 0, &cdev->ec_int,
980 			     GPIOD_IS_IN);
981 	cdev->optimise_flash_write = fdtdec_get_bool(blob, node,
982 						     "optimise-flash-write");
983 
984 	if (cros_ec_check_version(cdev)) {
985 		debug("%s: Could not detect CROS-EC version\n", __func__);
986 		return -CROS_EC_ERR_CHECK_VERSION;
987 	}
988 
989 	if (cros_ec_read_id(cdev, id, sizeof(id))) {
990 		debug("%s: Could not read KBC ID\n", __func__);
991 		return -CROS_EC_ERR_READ_ID;
992 	}
993 
994 	/* Remember this device for use by the cros_ec command */
995 	debug("Google Chrome EC v%d CROS-EC driver ready, id '%s'\n",
996 	      cdev->protocol_version, id);
997 
998 	return 0;
999 }
1000 
1001 int cros_ec_decode_region(int argc, char * const argv[])
1002 {
1003 	if (argc > 0) {
1004 		if (0 == strcmp(*argv, "rw"))
1005 			return EC_FLASH_REGION_RW;
1006 		else if (0 == strcmp(*argv, "ro"))
1007 			return EC_FLASH_REGION_RO;
1008 
1009 		debug("%s: Invalid region '%s'\n", __func__, *argv);
1010 	} else {
1011 		debug("%s: Missing region parameter\n", __func__);
1012 	}
1013 
1014 	return -1;
1015 }
1016 
1017 int cros_ec_decode_ec_flash(const void *blob, int node,
1018 			    struct fdt_cros_ec *config)
1019 {
1020 	int flash_node;
1021 
1022 	flash_node = fdt_subnode_offset(blob, node, "flash");
1023 	if (flash_node < 0) {
1024 		debug("Failed to find flash node\n");
1025 		return -1;
1026 	}
1027 
1028 	if (fdtdec_read_fmap_entry(blob, flash_node, "flash",
1029 				   &config->flash)) {
1030 		debug("Failed to decode flash node in chrome-ec'\n");
1031 		return -1;
1032 	}
1033 
1034 	config->flash_erase_value = fdtdec_get_int(blob, flash_node,
1035 						    "erase-value", -1);
1036 	for (node = fdt_first_subnode(blob, flash_node); node >= 0;
1037 	     node = fdt_next_subnode(blob, node)) {
1038 		const char *name = fdt_get_name(blob, node, NULL);
1039 		enum ec_flash_region region;
1040 
1041 		if (0 == strcmp(name, "ro")) {
1042 			region = EC_FLASH_REGION_RO;
1043 		} else if (0 == strcmp(name, "rw")) {
1044 			region = EC_FLASH_REGION_RW;
1045 		} else if (0 == strcmp(name, "wp-ro")) {
1046 			region = EC_FLASH_REGION_WP_RO;
1047 		} else {
1048 			debug("Unknown EC flash region name '%s'\n", name);
1049 			return -1;
1050 		}
1051 
1052 		if (fdtdec_read_fmap_entry(blob, node, "reg",
1053 					   &config->region[region])) {
1054 			debug("Failed to decode flash region in chrome-ec'\n");
1055 			return -1;
1056 		}
1057 	}
1058 
1059 	return 0;
1060 }
1061 
1062 int cros_ec_i2c_tunnel(struct udevice *dev, struct i2c_msg *in, int nmsgs)
1063 {
1064 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
1065 	union {
1066 		struct ec_params_i2c_passthru p;
1067 		uint8_t outbuf[EC_PROTO2_MAX_PARAM_SIZE];
1068 	} params;
1069 	union {
1070 		struct ec_response_i2c_passthru r;
1071 		uint8_t inbuf[EC_PROTO2_MAX_PARAM_SIZE];
1072 	} response;
1073 	struct ec_params_i2c_passthru *p = &params.p;
1074 	struct ec_response_i2c_passthru *r = &response.r;
1075 	struct ec_params_i2c_passthru_msg *msg;
1076 	uint8_t *pdata, *read_ptr = NULL;
1077 	int read_len;
1078 	int size;
1079 	int rv;
1080 	int i;
1081 
1082 	p->port = 0;
1083 
1084 	p->num_msgs = nmsgs;
1085 	size = sizeof(*p) + p->num_msgs * sizeof(*msg);
1086 
1087 	/* Create a message to write the register address and optional data */
1088 	pdata = (uint8_t *)p + size;
1089 
1090 	read_len = 0;
1091 	for (i = 0, msg = p->msg; i < nmsgs; i++, msg++, in++) {
1092 		bool is_read = in->flags & I2C_M_RD;
1093 
1094 		msg->addr_flags = in->addr;
1095 		msg->len = in->len;
1096 		if (is_read) {
1097 			msg->addr_flags |= EC_I2C_FLAG_READ;
1098 			read_len += in->len;
1099 			read_ptr = in->buf;
1100 			if (sizeof(*r) + read_len > sizeof(response)) {
1101 				puts("Read length too big for buffer\n");
1102 				return -1;
1103 			}
1104 		} else {
1105 			if (pdata - (uint8_t *)p + in->len > sizeof(params)) {
1106 				puts("Params too large for buffer\n");
1107 				return -1;
1108 			}
1109 			memcpy(pdata, in->buf, in->len);
1110 			pdata += in->len;
1111 		}
1112 	}
1113 
1114 	rv = ec_command(cdev, EC_CMD_I2C_PASSTHRU, 0, p, pdata - (uint8_t *)p,
1115 			r, sizeof(*r) + read_len);
1116 	if (rv < 0)
1117 		return rv;
1118 
1119 	/* Parse response */
1120 	if (r->i2c_status & EC_I2C_STATUS_ERROR) {
1121 		printf("Transfer failed with status=0x%x\n", r->i2c_status);
1122 		return -1;
1123 	}
1124 
1125 	if (rv < sizeof(*r) + read_len) {
1126 		puts("Truncated read response\n");
1127 		return -1;
1128 	}
1129 
1130 	/* We only support a single read message for each transfer */
1131 	if (read_len)
1132 		memcpy(read_ptr, r->data, read_len);
1133 
1134 	return 0;
1135 }
1136 
1137 #ifdef CONFIG_CMD_CROS_EC
1138 
1139 /**
1140  * Perform a flash read or write command
1141  *
1142  * @param dev		CROS-EC device to read/write
1143  * @param is_write	1 do to a write, 0 to do a read
1144  * @param argc		Number of arguments
1145  * @param argv		Arguments (2 is region, 3 is address)
1146  * @return 0 for ok, 1 for a usage error or -ve for ec command error
1147  *	(negative EC_RES_...)
1148  */
1149 static int do_read_write(struct cros_ec_dev *dev, int is_write, int argc,
1150 			 char * const argv[])
1151 {
1152 	uint32_t offset, size = -1U, region_size;
1153 	unsigned long addr;
1154 	char *endp;
1155 	int region;
1156 	int ret;
1157 
1158 	region = cros_ec_decode_region(argc - 2, argv + 2);
1159 	if (region == -1)
1160 		return 1;
1161 	if (argc < 4)
1162 		return 1;
1163 	addr = simple_strtoul(argv[3], &endp, 16);
1164 	if (*argv[3] == 0 || *endp != 0)
1165 		return 1;
1166 	if (argc > 4) {
1167 		size = simple_strtoul(argv[4], &endp, 16);
1168 		if (*argv[4] == 0 || *endp != 0)
1169 			return 1;
1170 	}
1171 
1172 	ret = cros_ec_flash_offset(dev, region, &offset, &region_size);
1173 	if (ret) {
1174 		debug("%s: Could not read region info\n", __func__);
1175 		return ret;
1176 	}
1177 	if (size == -1U)
1178 		size = region_size;
1179 
1180 	ret = is_write ?
1181 		cros_ec_flash_write(dev, (uint8_t *)addr, offset, size) :
1182 		cros_ec_flash_read(dev, (uint8_t *)addr, offset, size);
1183 	if (ret) {
1184 		debug("%s: Could not %s region\n", __func__,
1185 		      is_write ? "write" : "read");
1186 		return ret;
1187 	}
1188 
1189 	return 0;
1190 }
1191 
1192 static int do_cros_ec(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
1193 {
1194 	struct cros_ec_dev *dev;
1195 	struct udevice *udev;
1196 	const char *cmd;
1197 	int ret = 0;
1198 
1199 	if (argc < 2)
1200 		return CMD_RET_USAGE;
1201 
1202 	cmd = argv[1];
1203 	if (0 == strcmp("init", cmd)) {
1204 		/* Remove any existing device */
1205 		ret = uclass_find_device(UCLASS_CROS_EC, 0, &udev);
1206 		if (!ret)
1207 			device_remove(udev);
1208 		ret = uclass_get_device(UCLASS_CROS_EC, 0, &udev);
1209 		if (ret) {
1210 			printf("Could not init cros_ec device (err %d)\n", ret);
1211 			return 1;
1212 		}
1213 		return 0;
1214 	}
1215 
1216 	ret = uclass_get_device(UCLASS_CROS_EC, 0, &udev);
1217 	if (ret) {
1218 		printf("Cannot get cros-ec device (err=%d)\n", ret);
1219 		return 1;
1220 	}
1221 	dev = dev_get_uclass_priv(udev);
1222 	if (0 == strcmp("id", cmd)) {
1223 		char id[MSG_BYTES];
1224 
1225 		if (cros_ec_read_id(dev, id, sizeof(id))) {
1226 			debug("%s: Could not read KBC ID\n", __func__);
1227 			return 1;
1228 		}
1229 		printf("%s\n", id);
1230 	} else if (0 == strcmp("info", cmd)) {
1231 		struct ec_response_mkbp_info info;
1232 
1233 		if (cros_ec_info(dev, &info)) {
1234 			debug("%s: Could not read KBC info\n", __func__);
1235 			return 1;
1236 		}
1237 		printf("rows     = %u\n", info.rows);
1238 		printf("cols     = %u\n", info.cols);
1239 		printf("switches = %#x\n", info.switches);
1240 	} else if (0 == strcmp("curimage", cmd)) {
1241 		enum ec_current_image image;
1242 
1243 		if (cros_ec_read_current_image(dev, &image)) {
1244 			debug("%s: Could not read KBC image\n", __func__);
1245 			return 1;
1246 		}
1247 		printf("%d\n", image);
1248 	} else if (0 == strcmp("hash", cmd)) {
1249 		struct ec_response_vboot_hash hash;
1250 		int i;
1251 
1252 		if (cros_ec_read_hash(dev, &hash)) {
1253 			debug("%s: Could not read KBC hash\n", __func__);
1254 			return 1;
1255 		}
1256 
1257 		if (hash.hash_type == EC_VBOOT_HASH_TYPE_SHA256)
1258 			printf("type:    SHA-256\n");
1259 		else
1260 			printf("type:    %d\n", hash.hash_type);
1261 
1262 		printf("offset:  0x%08x\n", hash.offset);
1263 		printf("size:    0x%08x\n", hash.size);
1264 
1265 		printf("digest:  ");
1266 		for (i = 0; i < hash.digest_size; i++)
1267 			printf("%02x", hash.hash_digest[i]);
1268 		printf("\n");
1269 	} else if (0 == strcmp("reboot", cmd)) {
1270 		int region;
1271 		enum ec_reboot_cmd cmd;
1272 
1273 		if (argc >= 3 && !strcmp(argv[2], "cold"))
1274 			cmd = EC_REBOOT_COLD;
1275 		else {
1276 			region = cros_ec_decode_region(argc - 2, argv + 2);
1277 			if (region == EC_FLASH_REGION_RO)
1278 				cmd = EC_REBOOT_JUMP_RO;
1279 			else if (region == EC_FLASH_REGION_RW)
1280 				cmd = EC_REBOOT_JUMP_RW;
1281 			else
1282 				return CMD_RET_USAGE;
1283 		}
1284 
1285 		if (cros_ec_reboot(dev, cmd, 0)) {
1286 			debug("%s: Could not reboot KBC\n", __func__);
1287 			return 1;
1288 		}
1289 	} else if (0 == strcmp("events", cmd)) {
1290 		uint32_t events;
1291 
1292 		if (cros_ec_get_host_events(dev, &events)) {
1293 			debug("%s: Could not read host events\n", __func__);
1294 			return 1;
1295 		}
1296 		printf("0x%08x\n", events);
1297 	} else if (0 == strcmp("clrevents", cmd)) {
1298 		uint32_t events = 0x7fffffff;
1299 
1300 		if (argc >= 3)
1301 			events = simple_strtol(argv[2], NULL, 0);
1302 
1303 		if (cros_ec_clear_host_events(dev, events)) {
1304 			debug("%s: Could not clear host events\n", __func__);
1305 			return 1;
1306 		}
1307 	} else if (0 == strcmp("read", cmd)) {
1308 		ret = do_read_write(dev, 0, argc, argv);
1309 		if (ret > 0)
1310 			return CMD_RET_USAGE;
1311 	} else if (0 == strcmp("write", cmd)) {
1312 		ret = do_read_write(dev, 1, argc, argv);
1313 		if (ret > 0)
1314 			return CMD_RET_USAGE;
1315 	} else if (0 == strcmp("erase", cmd)) {
1316 		int region = cros_ec_decode_region(argc - 2, argv + 2);
1317 		uint32_t offset, size;
1318 
1319 		if (region == -1)
1320 			return CMD_RET_USAGE;
1321 		if (cros_ec_flash_offset(dev, region, &offset, &size)) {
1322 			debug("%s: Could not read region info\n", __func__);
1323 			ret = -1;
1324 		} else {
1325 			ret = cros_ec_flash_erase(dev, offset, size);
1326 			if (ret) {
1327 				debug("%s: Could not erase region\n",
1328 				      __func__);
1329 			}
1330 		}
1331 	} else if (0 == strcmp("regioninfo", cmd)) {
1332 		int region = cros_ec_decode_region(argc - 2, argv + 2);
1333 		uint32_t offset, size;
1334 
1335 		if (region == -1)
1336 			return CMD_RET_USAGE;
1337 		ret = cros_ec_flash_offset(dev, region, &offset, &size);
1338 		if (ret) {
1339 			debug("%s: Could not read region info\n", __func__);
1340 		} else {
1341 			printf("Region: %s\n", region == EC_FLASH_REGION_RO ?
1342 					"RO" : "RW");
1343 			printf("Offset: %x\n", offset);
1344 			printf("Size:   %x\n", size);
1345 		}
1346 	} else if (0 == strcmp("vbnvcontext", cmd)) {
1347 		uint8_t block[EC_VBNV_BLOCK_SIZE];
1348 		char buf[3];
1349 		int i, len;
1350 		unsigned long result;
1351 
1352 		if (argc <= 2) {
1353 			ret = cros_ec_read_vbnvcontext(dev, block);
1354 			if (!ret) {
1355 				printf("vbnv_block: ");
1356 				for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++)
1357 					printf("%02x", block[i]);
1358 				putc('\n');
1359 			}
1360 		} else {
1361 			/*
1362 			 * TODO(clchiou): Move this to a utility function as
1363 			 * cmd_spi might want to call it.
1364 			 */
1365 			memset(block, 0, EC_VBNV_BLOCK_SIZE);
1366 			len = strlen(argv[2]);
1367 			buf[2] = '\0';
1368 			for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++) {
1369 				if (i * 2 >= len)
1370 					break;
1371 				buf[0] = argv[2][i * 2];
1372 				if (i * 2 + 1 >= len)
1373 					buf[1] = '0';
1374 				else
1375 					buf[1] = argv[2][i * 2 + 1];
1376 				strict_strtoul(buf, 16, &result);
1377 				block[i] = result;
1378 			}
1379 			ret = cros_ec_write_vbnvcontext(dev, block);
1380 		}
1381 		if (ret) {
1382 			debug("%s: Could not %s VbNvContext\n", __func__,
1383 					argc <= 2 ?  "read" : "write");
1384 		}
1385 	} else if (0 == strcmp("test", cmd)) {
1386 		int result = cros_ec_test(dev);
1387 
1388 		if (result)
1389 			printf("Test failed with error %d\n", result);
1390 		else
1391 			puts("Test passed\n");
1392 	} else if (0 == strcmp("version", cmd)) {
1393 		struct ec_response_get_version *p;
1394 		char *build_string;
1395 
1396 		ret = cros_ec_read_version(dev, &p);
1397 		if (!ret) {
1398 			/* Print versions */
1399 			printf("RO version:    %1.*s\n",
1400 			       (int)sizeof(p->version_string_ro),
1401 			       p->version_string_ro);
1402 			printf("RW version:    %1.*s\n",
1403 			       (int)sizeof(p->version_string_rw),
1404 			       p->version_string_rw);
1405 			printf("Firmware copy: %s\n",
1406 				(p->current_image <
1407 					ARRAY_SIZE(ec_current_image_name) ?
1408 				ec_current_image_name[p->current_image] :
1409 				"?"));
1410 			ret = cros_ec_read_build_info(dev, &build_string);
1411 			if (!ret)
1412 				printf("Build info:    %s\n", build_string);
1413 		}
1414 	} else if (0 == strcmp("ldo", cmd)) {
1415 		uint8_t index, state;
1416 		char *endp;
1417 
1418 		if (argc < 3)
1419 			return CMD_RET_USAGE;
1420 		index = simple_strtoul(argv[2], &endp, 10);
1421 		if (*argv[2] == 0 || *endp != 0)
1422 			return CMD_RET_USAGE;
1423 		if (argc > 3) {
1424 			state = simple_strtoul(argv[3], &endp, 10);
1425 			if (*argv[3] == 0 || *endp != 0)
1426 				return CMD_RET_USAGE;
1427 			ret = cros_ec_set_ldo(udev, index, state);
1428 		} else {
1429 			ret = cros_ec_get_ldo(udev, index, &state);
1430 			if (!ret) {
1431 				printf("LDO%d: %s\n", index,
1432 					state == EC_LDO_STATE_ON ?
1433 					"on" : "off");
1434 			}
1435 		}
1436 
1437 		if (ret) {
1438 			debug("%s: Could not access LDO%d\n", __func__, index);
1439 			return ret;
1440 		}
1441 	} else {
1442 		return CMD_RET_USAGE;
1443 	}
1444 
1445 	if (ret < 0) {
1446 		printf("Error: CROS-EC command failed (error %d)\n", ret);
1447 		ret = 1;
1448 	}
1449 
1450 	return ret;
1451 }
1452 
1453 int cros_ec_post_bind(struct udevice *dev)
1454 {
1455 	/* Scan for available EC devices (e.g. I2C tunnel) */
1456 	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
1457 }
1458 
1459 U_BOOT_CMD(
1460 	crosec,	6,	1,	do_cros_ec,
1461 	"CROS-EC utility command",
1462 	"init                Re-init CROS-EC (done on startup automatically)\n"
1463 	"crosec id                  Read CROS-EC ID\n"
1464 	"crosec info                Read CROS-EC info\n"
1465 	"crosec curimage            Read CROS-EC current image\n"
1466 	"crosec hash                Read CROS-EC hash\n"
1467 	"crosec reboot [rw | ro | cold]  Reboot CROS-EC\n"
1468 	"crosec events              Read CROS-EC host events\n"
1469 	"crosec clrevents [mask]    Clear CROS-EC host events\n"
1470 	"crosec regioninfo <ro|rw>  Read image info\n"
1471 	"crosec erase <ro|rw>       Erase EC image\n"
1472 	"crosec read <ro|rw> <addr> [<size>]   Read EC image\n"
1473 	"crosec write <ro|rw> <addr> [<size>]  Write EC image\n"
1474 	"crosec vbnvcontext [hexstring]        Read [write] VbNvContext from EC\n"
1475 	"crosec ldo <idx> [<state>] Switch/Read LDO state\n"
1476 	"crosec test                run tests on cros_ec\n"
1477 	"crosec version             Read CROS-EC version"
1478 );
1479 #endif
1480 
1481 UCLASS_DRIVER(cros_ec) = {
1482 	.id		= UCLASS_CROS_EC,
1483 	.name		= "cros_ec",
1484 	.per_device_auto_alloc_size = sizeof(struct cros_ec_dev),
1485 	.post_bind	= cros_ec_post_bind,
1486 };
1487