xref: /openbmc/u-boot/drivers/misc/cros_ec.c (revision cc4f1558)
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 cros_ec_dev *dev, struct mbkp_keyscan *scan)
362 {
363 	if (ec_command(dev, EC_CMD_MKBP_STATE, 0, NULL, 0, scan,
364 		       sizeof(scan->data)) != sizeof(scan->data))
365 		return -1;
366 
367 	return 0;
368 }
369 
370 int cros_ec_read_id(struct cros_ec_dev *dev, char *id, int maxlen)
371 {
372 	struct ec_response_get_version *r;
373 
374 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
375 			(uint8_t **)&r, sizeof(*r)) != sizeof(*r))
376 		return -1;
377 
378 	if (maxlen > (int)sizeof(r->version_string_ro))
379 		maxlen = sizeof(r->version_string_ro);
380 
381 	switch (r->current_image) {
382 	case EC_IMAGE_RO:
383 		memcpy(id, r->version_string_ro, maxlen);
384 		break;
385 	case EC_IMAGE_RW:
386 		memcpy(id, r->version_string_rw, maxlen);
387 		break;
388 	default:
389 		return -1;
390 	}
391 
392 	id[maxlen - 1] = '\0';
393 	return 0;
394 }
395 
396 int cros_ec_read_version(struct cros_ec_dev *dev,
397 		       struct ec_response_get_version **versionp)
398 {
399 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
400 			(uint8_t **)versionp, sizeof(**versionp))
401 			!= sizeof(**versionp))
402 		return -1;
403 
404 	return 0;
405 }
406 
407 int cros_ec_read_build_info(struct cros_ec_dev *dev, char **strp)
408 {
409 	if (ec_command_inptr(dev, EC_CMD_GET_BUILD_INFO, 0, NULL, 0,
410 			(uint8_t **)strp, EC_PROTO2_MAX_PARAM_SIZE) < 0)
411 		return -1;
412 
413 	return 0;
414 }
415 
416 int cros_ec_read_current_image(struct cros_ec_dev *dev,
417 		enum ec_current_image *image)
418 {
419 	struct ec_response_get_version *r;
420 
421 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
422 			(uint8_t **)&r, sizeof(*r)) != sizeof(*r))
423 		return -1;
424 
425 	*image = r->current_image;
426 	return 0;
427 }
428 
429 static int cros_ec_wait_on_hash_done(struct cros_ec_dev *dev,
430 				  struct ec_response_vboot_hash *hash)
431 {
432 	struct ec_params_vboot_hash p;
433 	ulong start;
434 
435 	start = get_timer(0);
436 	while (hash->status == EC_VBOOT_HASH_STATUS_BUSY) {
437 		mdelay(50);	/* Insert some reasonable delay */
438 
439 		p.cmd = EC_VBOOT_HASH_GET;
440 		if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
441 		       hash, sizeof(*hash)) < 0)
442 			return -1;
443 
444 		if (get_timer(start) > CROS_EC_CMD_HASH_TIMEOUT_MS) {
445 			debug("%s: EC_VBOOT_HASH_GET timeout\n", __func__);
446 			return -EC_RES_TIMEOUT;
447 		}
448 	}
449 	return 0;
450 }
451 
452 
453 int cros_ec_read_hash(struct cros_ec_dev *dev,
454 		struct ec_response_vboot_hash *hash)
455 {
456 	struct ec_params_vboot_hash p;
457 	int rv;
458 
459 	p.cmd = EC_VBOOT_HASH_GET;
460 	if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
461 		       hash, sizeof(*hash)) < 0)
462 		return -1;
463 
464 	/* If the EC is busy calculating the hash, fidget until it's done. */
465 	rv = cros_ec_wait_on_hash_done(dev, hash);
466 	if (rv)
467 		return rv;
468 
469 	/* If the hash is valid, we're done. Otherwise, we have to kick it off
470 	 * again and wait for it to complete. Note that we explicitly assume
471 	 * that hashing zero bytes is always wrong, even though that would
472 	 * produce a valid hash value. */
473 	if (hash->status == EC_VBOOT_HASH_STATUS_DONE && hash->size)
474 		return 0;
475 
476 	debug("%s: No valid hash (status=%d size=%d). Compute one...\n",
477 	      __func__, hash->status, hash->size);
478 
479 	p.cmd = EC_VBOOT_HASH_START;
480 	p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
481 	p.nonce_size = 0;
482 	p.offset = EC_VBOOT_HASH_OFFSET_RW;
483 
484 	if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
485 		       hash, sizeof(*hash)) < 0)
486 		return -1;
487 
488 	rv = cros_ec_wait_on_hash_done(dev, hash);
489 	if (rv)
490 		return rv;
491 
492 	debug("%s: hash done\n", __func__);
493 
494 	return 0;
495 }
496 
497 static int cros_ec_invalidate_hash(struct cros_ec_dev *dev)
498 {
499 	struct ec_params_vboot_hash p;
500 	struct ec_response_vboot_hash *hash;
501 
502 	/* We don't have an explict command for the EC to discard its current
503 	 * hash value, so we'll just tell it to calculate one that we know is
504 	 * wrong (we claim that hashing zero bytes is always invalid).
505 	 */
506 	p.cmd = EC_VBOOT_HASH_RECALC;
507 	p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
508 	p.nonce_size = 0;
509 	p.offset = 0;
510 	p.size = 0;
511 
512 	debug("%s:\n", __func__);
513 
514 	if (ec_command_inptr(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
515 		       (uint8_t **)&hash, sizeof(*hash)) < 0)
516 		return -1;
517 
518 	/* No need to wait for it to finish */
519 	return 0;
520 }
521 
522 int cros_ec_reboot(struct cros_ec_dev *dev, enum ec_reboot_cmd cmd,
523 		uint8_t flags)
524 {
525 	struct ec_params_reboot_ec p;
526 
527 	p.cmd = cmd;
528 	p.flags = flags;
529 
530 	if (ec_command_inptr(dev, EC_CMD_REBOOT_EC, 0, &p, sizeof(p), NULL, 0)
531 			< 0)
532 		return -1;
533 
534 	if (!(flags & EC_REBOOT_FLAG_ON_AP_SHUTDOWN)) {
535 		/*
536 		 * EC reboot will take place immediately so delay to allow it
537 		 * to complete.  Note that some reboot types (EC_REBOOT_COLD)
538 		 * will reboot the AP as well, in which case we won't actually
539 		 * get to this point.
540 		 */
541 		/*
542 		 * TODO(rspangler@chromium.org): Would be nice if we had a
543 		 * better way to determine when the reboot is complete.  Could
544 		 * we poll a memory-mapped LPC value?
545 		 */
546 		udelay(50000);
547 	}
548 
549 	return 0;
550 }
551 
552 int cros_ec_interrupt_pending(struct cros_ec_dev *dev)
553 {
554 	/* no interrupt support : always poll */
555 	if (!dm_gpio_is_valid(&dev->ec_int))
556 		return -ENOENT;
557 
558 	return dm_gpio_get_value(&dev->ec_int);
559 }
560 
561 int cros_ec_info(struct cros_ec_dev *dev, struct ec_response_mkbp_info *info)
562 {
563 	if (ec_command(dev, EC_CMD_MKBP_INFO, 0, NULL, 0, info,
564 		       sizeof(*info)) != sizeof(*info))
565 		return -1;
566 
567 	return 0;
568 }
569 
570 int cros_ec_get_host_events(struct cros_ec_dev *dev, uint32_t *events_ptr)
571 {
572 	struct ec_response_host_event_mask *resp;
573 
574 	/*
575 	 * Use the B copy of the event flags, because the main copy is already
576 	 * used by ACPI/SMI.
577 	 */
578 	if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_GET_B, 0, NULL, 0,
579 		       (uint8_t **)&resp, sizeof(*resp)) < (int)sizeof(*resp))
580 		return -1;
581 
582 	if (resp->mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INVALID))
583 		return -1;
584 
585 	*events_ptr = resp->mask;
586 	return 0;
587 }
588 
589 int cros_ec_clear_host_events(struct cros_ec_dev *dev, uint32_t events)
590 {
591 	struct ec_params_host_event_mask params;
592 
593 	params.mask = events;
594 
595 	/*
596 	 * Use the B copy of the event flags, so it affects the data returned
597 	 * by cros_ec_get_host_events().
598 	 */
599 	if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_CLEAR_B, 0,
600 		       &params, sizeof(params), NULL, 0) < 0)
601 		return -1;
602 
603 	return 0;
604 }
605 
606 int cros_ec_flash_protect(struct cros_ec_dev *dev,
607 		       uint32_t set_mask, uint32_t set_flags,
608 		       struct ec_response_flash_protect *resp)
609 {
610 	struct ec_params_flash_protect params;
611 
612 	params.mask = set_mask;
613 	params.flags = set_flags;
614 
615 	if (ec_command(dev, EC_CMD_FLASH_PROTECT, EC_VER_FLASH_PROTECT,
616 		       &params, sizeof(params),
617 		       resp, sizeof(*resp)) != sizeof(*resp))
618 		return -1;
619 
620 	return 0;
621 }
622 
623 static int cros_ec_check_version(struct cros_ec_dev *dev)
624 {
625 	struct ec_params_hello req;
626 	struct ec_response_hello *resp;
627 
628 	struct dm_cros_ec_ops *ops;
629 	int ret;
630 
631 	ops = dm_cros_ec_get_ops(dev->dev);
632 	if (ops->check_version) {
633 		ret = ops->check_version(dev->dev);
634 		if (ret)
635 			return ret;
636 	}
637 
638 	/*
639 	 * TODO(sjg@chromium.org).
640 	 * There is a strange oddity here with the EC. We could just ignore
641 	 * the response, i.e. pass the last two parameters as NULL and 0.
642 	 * In this case we won't read back very many bytes from the EC.
643 	 * On the I2C bus the EC gets upset about this and will try to send
644 	 * the bytes anyway. This means that we will have to wait for that
645 	 * to complete before continuing with a new EC command.
646 	 *
647 	 * This problem is probably unique to the I2C bus.
648 	 *
649 	 * So for now, just read all the data anyway.
650 	 */
651 
652 	/* Try sending a version 3 packet */
653 	dev->protocol_version = 3;
654 	req.in_data = 0;
655 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
656 			     (uint8_t **)&resp, sizeof(*resp)) > 0) {
657 		return 0;
658 	}
659 
660 	/* Try sending a version 2 packet */
661 	dev->protocol_version = 2;
662 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
663 		       (uint8_t **)&resp, sizeof(*resp)) > 0) {
664 		return 0;
665 	}
666 
667 	/*
668 	 * Fail if we're still here, since the EC doesn't understand any
669 	 * protcol version we speak.  Version 1 interface without command
670 	 * version is no longer supported, and we don't know about any new
671 	 * protocol versions.
672 	 */
673 	dev->protocol_version = 0;
674 	printf("%s: ERROR: old EC interface not supported\n", __func__);
675 	return -1;
676 }
677 
678 int cros_ec_test(struct cros_ec_dev *dev)
679 {
680 	struct ec_params_hello req;
681 	struct ec_response_hello *resp;
682 
683 	req.in_data = 0x12345678;
684 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
685 		       (uint8_t **)&resp, sizeof(*resp)) < sizeof(*resp)) {
686 		printf("ec_command_inptr() returned error\n");
687 		return -1;
688 	}
689 	if (resp->out_data != req.in_data + 0x01020304) {
690 		printf("Received invalid handshake %x\n", resp->out_data);
691 		return -1;
692 	}
693 
694 	return 0;
695 }
696 
697 int cros_ec_flash_offset(struct cros_ec_dev *dev, enum ec_flash_region region,
698 		      uint32_t *offset, uint32_t *size)
699 {
700 	struct ec_params_flash_region_info p;
701 	struct ec_response_flash_region_info *r;
702 	int ret;
703 
704 	p.region = region;
705 	ret = ec_command_inptr(dev, EC_CMD_FLASH_REGION_INFO,
706 			 EC_VER_FLASH_REGION_INFO,
707 			 &p, sizeof(p), (uint8_t **)&r, sizeof(*r));
708 	if (ret != sizeof(*r))
709 		return -1;
710 
711 	if (offset)
712 		*offset = r->offset;
713 	if (size)
714 		*size = r->size;
715 
716 	return 0;
717 }
718 
719 int cros_ec_flash_erase(struct cros_ec_dev *dev, uint32_t offset, uint32_t size)
720 {
721 	struct ec_params_flash_erase p;
722 
723 	p.offset = offset;
724 	p.size = size;
725 	return ec_command_inptr(dev, EC_CMD_FLASH_ERASE, 0, &p, sizeof(p),
726 			NULL, 0);
727 }
728 
729 /**
730  * Write a single block to the flash
731  *
732  * Write a block of data to the EC flash. The size must not exceed the flash
733  * write block size which you can obtain from cros_ec_flash_write_burst_size().
734  *
735  * The offset starts at 0. You can obtain the region information from
736  * cros_ec_flash_offset() to find out where to write for a particular region.
737  *
738  * Attempting to write to the region where the EC is currently running from
739  * will result in an error.
740  *
741  * @param dev		CROS-EC device
742  * @param data		Pointer to data buffer to write
743  * @param offset	Offset within flash to write to.
744  * @param size		Number of bytes to write
745  * @return 0 if ok, -1 on error
746  */
747 static int cros_ec_flash_write_block(struct cros_ec_dev *dev,
748 		const uint8_t *data, uint32_t offset, uint32_t size)
749 {
750 	struct ec_params_flash_write p;
751 
752 	p.offset = offset;
753 	p.size = size;
754 	assert(data && p.size <= EC_FLASH_WRITE_VER0_SIZE);
755 	memcpy(&p + 1, data, p.size);
756 
757 	return ec_command_inptr(dev, EC_CMD_FLASH_WRITE, 0,
758 			  &p, sizeof(p), NULL, 0) >= 0 ? 0 : -1;
759 }
760 
761 /**
762  * Return optimal flash write burst size
763  */
764 static int cros_ec_flash_write_burst_size(struct cros_ec_dev *dev)
765 {
766 	return EC_FLASH_WRITE_VER0_SIZE;
767 }
768 
769 /**
770  * Check if a block of data is erased (all 0xff)
771  *
772  * This function is useful when dealing with flash, for checking whether a
773  * data block is erased and thus does not need to be programmed.
774  *
775  * @param data		Pointer to data to check (must be word-aligned)
776  * @param size		Number of bytes to check (must be word-aligned)
777  * @return 0 if erased, non-zero if any word is not erased
778  */
779 static int cros_ec_data_is_erased(const uint32_t *data, int size)
780 {
781 	assert(!(size & 3));
782 	size /= sizeof(uint32_t);
783 	for (; size > 0; size -= 4, data++)
784 		if (*data != -1U)
785 			return 0;
786 
787 	return 1;
788 }
789 
790 int cros_ec_flash_write(struct cros_ec_dev *dev, const uint8_t *data,
791 		     uint32_t offset, uint32_t size)
792 {
793 	uint32_t burst = cros_ec_flash_write_burst_size(dev);
794 	uint32_t end, off;
795 	int ret;
796 
797 	/*
798 	 * TODO: round up to the nearest multiple of write size.  Can get away
799 	 * without that on link right now because its write size is 4 bytes.
800 	 */
801 	end = offset + size;
802 	for (off = offset; off < end; off += burst, data += burst) {
803 		uint32_t todo;
804 
805 		/* If the data is empty, there is no point in programming it */
806 		todo = min(end - off, burst);
807 		if (dev->optimise_flash_write &&
808 				cros_ec_data_is_erased((uint32_t *)data, todo))
809 			continue;
810 
811 		ret = cros_ec_flash_write_block(dev, data, off, todo);
812 		if (ret)
813 			return ret;
814 	}
815 
816 	return 0;
817 }
818 
819 /**
820  * Read a single block from the flash
821  *
822  * Read a block of data from the EC flash. The size must not exceed the flash
823  * write block size which you can obtain from cros_ec_flash_write_burst_size().
824  *
825  * The offset starts at 0. You can obtain the region information from
826  * cros_ec_flash_offset() to find out where to read for a particular region.
827  *
828  * @param dev		CROS-EC device
829  * @param data		Pointer to data buffer to read into
830  * @param offset	Offset within flash to read from
831  * @param size		Number of bytes to read
832  * @return 0 if ok, -1 on error
833  */
834 static int cros_ec_flash_read_block(struct cros_ec_dev *dev, uint8_t *data,
835 				 uint32_t offset, uint32_t size)
836 {
837 	struct ec_params_flash_read p;
838 
839 	p.offset = offset;
840 	p.size = size;
841 
842 	return ec_command(dev, EC_CMD_FLASH_READ, 0,
843 			  &p, sizeof(p), data, size) >= 0 ? 0 : -1;
844 }
845 
846 int cros_ec_flash_read(struct cros_ec_dev *dev, uint8_t *data, uint32_t offset,
847 		    uint32_t size)
848 {
849 	uint32_t burst = cros_ec_flash_write_burst_size(dev);
850 	uint32_t end, off;
851 	int ret;
852 
853 	end = offset + size;
854 	for (off = offset; off < end; off += burst, data += burst) {
855 		ret = cros_ec_flash_read_block(dev, data, off,
856 					    min(end - off, burst));
857 		if (ret)
858 			return ret;
859 	}
860 
861 	return 0;
862 }
863 
864 int cros_ec_flash_update_rw(struct cros_ec_dev *dev,
865 			 const uint8_t *image, int image_size)
866 {
867 	uint32_t rw_offset, rw_size;
868 	int ret;
869 
870 	if (cros_ec_flash_offset(dev, EC_FLASH_REGION_RW, &rw_offset, &rw_size))
871 		return -1;
872 	if (image_size > (int)rw_size)
873 		return -1;
874 
875 	/* Invalidate the existing hash, just in case the AP reboots
876 	 * unexpectedly during the update. If that happened, the EC RW firmware
877 	 * would be invalid, but the EC would still have the original hash.
878 	 */
879 	ret = cros_ec_invalidate_hash(dev);
880 	if (ret)
881 		return ret;
882 
883 	/*
884 	 * Erase the entire RW section, so that the EC doesn't see any garbage
885 	 * past the new image if it's smaller than the current image.
886 	 *
887 	 * TODO: could optimize this to erase just the current image, since
888 	 * presumably everything past that is 0xff's.  But would still need to
889 	 * round up to the nearest multiple of erase size.
890 	 */
891 	ret = cros_ec_flash_erase(dev, rw_offset, rw_size);
892 	if (ret)
893 		return ret;
894 
895 	/* Write the image */
896 	ret = cros_ec_flash_write(dev, image, rw_offset, image_size);
897 	if (ret)
898 		return ret;
899 
900 	return 0;
901 }
902 
903 int cros_ec_read_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block)
904 {
905 	struct ec_params_vbnvcontext p;
906 	int len;
907 
908 	p.op = EC_VBNV_CONTEXT_OP_READ;
909 
910 	len = ec_command(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
911 			&p, sizeof(p), block, EC_VBNV_BLOCK_SIZE);
912 	if (len < EC_VBNV_BLOCK_SIZE)
913 		return -1;
914 
915 	return 0;
916 }
917 
918 int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block)
919 {
920 	struct ec_params_vbnvcontext p;
921 	int len;
922 
923 	p.op = EC_VBNV_CONTEXT_OP_WRITE;
924 	memcpy(p.block, block, sizeof(p.block));
925 
926 	len = ec_command_inptr(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
927 			&p, sizeof(p), NULL, 0);
928 	if (len < 0)
929 		return -1;
930 
931 	return 0;
932 }
933 
934 int cros_ec_set_ldo(struct udevice *dev, uint8_t index, uint8_t state)
935 {
936 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
937 	struct ec_params_ldo_set params;
938 
939 	params.index = index;
940 	params.state = state;
941 
942 	if (ec_command_inptr(cdev, EC_CMD_LDO_SET, 0, &params, sizeof(params),
943 			     NULL, 0))
944 		return -1;
945 
946 	return 0;
947 }
948 
949 int cros_ec_get_ldo(struct udevice *dev, uint8_t index, uint8_t *state)
950 {
951 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
952 	struct ec_params_ldo_get params;
953 	struct ec_response_ldo_get *resp;
954 
955 	params.index = index;
956 
957 	if (ec_command_inptr(cdev, EC_CMD_LDO_GET, 0, &params, sizeof(params),
958 			     (uint8_t **)&resp, sizeof(*resp)) !=
959 			     sizeof(*resp))
960 		return -1;
961 
962 	*state = resp->state;
963 
964 	return 0;
965 }
966 
967 int cros_ec_register(struct udevice *dev)
968 {
969 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
970 	const void *blob = gd->fdt_blob;
971 	int node = dev->of_offset;
972 	char id[MSG_BYTES];
973 
974 	cdev->dev = dev;
975 	gpio_request_by_name(dev, "ec-interrupt", 0, &cdev->ec_int,
976 			     GPIOD_IS_IN);
977 	cdev->optimise_flash_write = fdtdec_get_bool(blob, node,
978 						     "optimise-flash-write");
979 
980 	if (cros_ec_check_version(cdev)) {
981 		debug("%s: Could not detect CROS-EC version\n", __func__);
982 		return -CROS_EC_ERR_CHECK_VERSION;
983 	}
984 
985 	if (cros_ec_read_id(cdev, id, sizeof(id))) {
986 		debug("%s: Could not read KBC ID\n", __func__);
987 		return -CROS_EC_ERR_READ_ID;
988 	}
989 
990 	/* Remember this device for use by the cros_ec command */
991 	debug("Google Chrome EC v%d CROS-EC driver ready, id '%s'\n",
992 	      cdev->protocol_version, id);
993 
994 	return 0;
995 }
996 
997 int cros_ec_decode_region(int argc, char * const argv[])
998 {
999 	if (argc > 0) {
1000 		if (0 == strcmp(*argv, "rw"))
1001 			return EC_FLASH_REGION_RW;
1002 		else if (0 == strcmp(*argv, "ro"))
1003 			return EC_FLASH_REGION_RO;
1004 
1005 		debug("%s: Invalid region '%s'\n", __func__, *argv);
1006 	} else {
1007 		debug("%s: Missing region parameter\n", __func__);
1008 	}
1009 
1010 	return -1;
1011 }
1012 
1013 int cros_ec_decode_ec_flash(const void *blob, int node,
1014 			    struct fdt_cros_ec *config)
1015 {
1016 	int flash_node;
1017 
1018 	flash_node = fdt_subnode_offset(blob, node, "flash");
1019 	if (flash_node < 0) {
1020 		debug("Failed to find flash node\n");
1021 		return -1;
1022 	}
1023 
1024 	if (fdtdec_read_fmap_entry(blob, flash_node, "flash",
1025 				   &config->flash)) {
1026 		debug("Failed to decode flash node in chrome-ec'\n");
1027 		return -1;
1028 	}
1029 
1030 	config->flash_erase_value = fdtdec_get_int(blob, flash_node,
1031 						    "erase-value", -1);
1032 	for (node = fdt_first_subnode(blob, flash_node); node >= 0;
1033 	     node = fdt_next_subnode(blob, node)) {
1034 		const char *name = fdt_get_name(blob, node, NULL);
1035 		enum ec_flash_region region;
1036 
1037 		if (0 == strcmp(name, "ro")) {
1038 			region = EC_FLASH_REGION_RO;
1039 		} else if (0 == strcmp(name, "rw")) {
1040 			region = EC_FLASH_REGION_RW;
1041 		} else if (0 == strcmp(name, "wp-ro")) {
1042 			region = EC_FLASH_REGION_WP_RO;
1043 		} else {
1044 			debug("Unknown EC flash region name '%s'\n", name);
1045 			return -1;
1046 		}
1047 
1048 		if (fdtdec_read_fmap_entry(blob, node, "reg",
1049 					   &config->region[region])) {
1050 			debug("Failed to decode flash region in chrome-ec'\n");
1051 			return -1;
1052 		}
1053 	}
1054 
1055 	return 0;
1056 }
1057 
1058 int cros_ec_i2c_tunnel(struct udevice *dev, struct i2c_msg *in, int nmsgs)
1059 {
1060 	struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
1061 	union {
1062 		struct ec_params_i2c_passthru p;
1063 		uint8_t outbuf[EC_PROTO2_MAX_PARAM_SIZE];
1064 	} params;
1065 	union {
1066 		struct ec_response_i2c_passthru r;
1067 		uint8_t inbuf[EC_PROTO2_MAX_PARAM_SIZE];
1068 	} response;
1069 	struct ec_params_i2c_passthru *p = &params.p;
1070 	struct ec_response_i2c_passthru *r = &response.r;
1071 	struct ec_params_i2c_passthru_msg *msg;
1072 	uint8_t *pdata, *read_ptr = NULL;
1073 	int read_len;
1074 	int size;
1075 	int rv;
1076 	int i;
1077 
1078 	p->port = 0;
1079 
1080 	p->num_msgs = nmsgs;
1081 	size = sizeof(*p) + p->num_msgs * sizeof(*msg);
1082 
1083 	/* Create a message to write the register address and optional data */
1084 	pdata = (uint8_t *)p + size;
1085 
1086 	read_len = 0;
1087 	for (i = 0, msg = p->msg; i < nmsgs; i++, msg++, in++) {
1088 		bool is_read = in->flags & I2C_M_RD;
1089 
1090 		msg->addr_flags = in->addr;
1091 		msg->len = in->len;
1092 		if (is_read) {
1093 			msg->addr_flags |= EC_I2C_FLAG_READ;
1094 			read_len += in->len;
1095 			read_ptr = in->buf;
1096 			if (sizeof(*r) + read_len > sizeof(response)) {
1097 				puts("Read length too big for buffer\n");
1098 				return -1;
1099 			}
1100 		} else {
1101 			if (pdata - (uint8_t *)p + in->len > sizeof(params)) {
1102 				puts("Params too large for buffer\n");
1103 				return -1;
1104 			}
1105 			memcpy(pdata, in->buf, in->len);
1106 			pdata += in->len;
1107 		}
1108 	}
1109 
1110 	rv = ec_command(cdev, EC_CMD_I2C_PASSTHRU, 0, p, pdata - (uint8_t *)p,
1111 			r, sizeof(*r) + read_len);
1112 	if (rv < 0)
1113 		return rv;
1114 
1115 	/* Parse response */
1116 	if (r->i2c_status & EC_I2C_STATUS_ERROR) {
1117 		printf("Transfer failed with status=0x%x\n", r->i2c_status);
1118 		return -1;
1119 	}
1120 
1121 	if (rv < sizeof(*r) + read_len) {
1122 		puts("Truncated read response\n");
1123 		return -1;
1124 	}
1125 
1126 	/* We only support a single read message for each transfer */
1127 	if (read_len)
1128 		memcpy(read_ptr, r->data, read_len);
1129 
1130 	return 0;
1131 }
1132 
1133 #ifdef CONFIG_CMD_CROS_EC
1134 
1135 /**
1136  * Perform a flash read or write command
1137  *
1138  * @param dev		CROS-EC device to read/write
1139  * @param is_write	1 do to a write, 0 to do a read
1140  * @param argc		Number of arguments
1141  * @param argv		Arguments (2 is region, 3 is address)
1142  * @return 0 for ok, 1 for a usage error or -ve for ec command error
1143  *	(negative EC_RES_...)
1144  */
1145 static int do_read_write(struct cros_ec_dev *dev, int is_write, int argc,
1146 			 char * const argv[])
1147 {
1148 	uint32_t offset, size = -1U, region_size;
1149 	unsigned long addr;
1150 	char *endp;
1151 	int region;
1152 	int ret;
1153 
1154 	region = cros_ec_decode_region(argc - 2, argv + 2);
1155 	if (region == -1)
1156 		return 1;
1157 	if (argc < 4)
1158 		return 1;
1159 	addr = simple_strtoul(argv[3], &endp, 16);
1160 	if (*argv[3] == 0 || *endp != 0)
1161 		return 1;
1162 	if (argc > 4) {
1163 		size = simple_strtoul(argv[4], &endp, 16);
1164 		if (*argv[4] == 0 || *endp != 0)
1165 			return 1;
1166 	}
1167 
1168 	ret = cros_ec_flash_offset(dev, region, &offset, &region_size);
1169 	if (ret) {
1170 		debug("%s: Could not read region info\n", __func__);
1171 		return ret;
1172 	}
1173 	if (size == -1U)
1174 		size = region_size;
1175 
1176 	ret = is_write ?
1177 		cros_ec_flash_write(dev, (uint8_t *)addr, offset, size) :
1178 		cros_ec_flash_read(dev, (uint8_t *)addr, offset, size);
1179 	if (ret) {
1180 		debug("%s: Could not %s region\n", __func__,
1181 		      is_write ? "write" : "read");
1182 		return ret;
1183 	}
1184 
1185 	return 0;
1186 }
1187 
1188 static int do_cros_ec(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
1189 {
1190 	struct cros_ec_dev *dev;
1191 	struct udevice *udev;
1192 	const char *cmd;
1193 	int ret = 0;
1194 
1195 	if (argc < 2)
1196 		return CMD_RET_USAGE;
1197 
1198 	cmd = argv[1];
1199 	if (0 == strcmp("init", cmd)) {
1200 		/* Remove any existing device */
1201 		ret = uclass_find_device(UCLASS_CROS_EC, 0, &udev);
1202 		if (!ret)
1203 			device_remove(udev);
1204 		ret = uclass_get_device(UCLASS_CROS_EC, 0, &udev);
1205 		if (ret) {
1206 			printf("Could not init cros_ec device (err %d)\n", ret);
1207 			return 1;
1208 		}
1209 		return 0;
1210 	}
1211 
1212 	ret = uclass_get_device(UCLASS_CROS_EC, 0, &udev);
1213 	if (ret) {
1214 		printf("Cannot get cros-ec device (err=%d)\n", ret);
1215 		return 1;
1216 	}
1217 	dev = dev_get_uclass_priv(udev);
1218 	if (0 == strcmp("id", cmd)) {
1219 		char id[MSG_BYTES];
1220 
1221 		if (cros_ec_read_id(dev, id, sizeof(id))) {
1222 			debug("%s: Could not read KBC ID\n", __func__);
1223 			return 1;
1224 		}
1225 		printf("%s\n", id);
1226 	} else if (0 == strcmp("info", cmd)) {
1227 		struct ec_response_mkbp_info info;
1228 
1229 		if (cros_ec_info(dev, &info)) {
1230 			debug("%s: Could not read KBC info\n", __func__);
1231 			return 1;
1232 		}
1233 		printf("rows     = %u\n", info.rows);
1234 		printf("cols     = %u\n", info.cols);
1235 		printf("switches = %#x\n", info.switches);
1236 	} else if (0 == strcmp("curimage", cmd)) {
1237 		enum ec_current_image image;
1238 
1239 		if (cros_ec_read_current_image(dev, &image)) {
1240 			debug("%s: Could not read KBC image\n", __func__);
1241 			return 1;
1242 		}
1243 		printf("%d\n", image);
1244 	} else if (0 == strcmp("hash", cmd)) {
1245 		struct ec_response_vboot_hash hash;
1246 		int i;
1247 
1248 		if (cros_ec_read_hash(dev, &hash)) {
1249 			debug("%s: Could not read KBC hash\n", __func__);
1250 			return 1;
1251 		}
1252 
1253 		if (hash.hash_type == EC_VBOOT_HASH_TYPE_SHA256)
1254 			printf("type:    SHA-256\n");
1255 		else
1256 			printf("type:    %d\n", hash.hash_type);
1257 
1258 		printf("offset:  0x%08x\n", hash.offset);
1259 		printf("size:    0x%08x\n", hash.size);
1260 
1261 		printf("digest:  ");
1262 		for (i = 0; i < hash.digest_size; i++)
1263 			printf("%02x", hash.hash_digest[i]);
1264 		printf("\n");
1265 	} else if (0 == strcmp("reboot", cmd)) {
1266 		int region;
1267 		enum ec_reboot_cmd cmd;
1268 
1269 		if (argc >= 3 && !strcmp(argv[2], "cold"))
1270 			cmd = EC_REBOOT_COLD;
1271 		else {
1272 			region = cros_ec_decode_region(argc - 2, argv + 2);
1273 			if (region == EC_FLASH_REGION_RO)
1274 				cmd = EC_REBOOT_JUMP_RO;
1275 			else if (region == EC_FLASH_REGION_RW)
1276 				cmd = EC_REBOOT_JUMP_RW;
1277 			else
1278 				return CMD_RET_USAGE;
1279 		}
1280 
1281 		if (cros_ec_reboot(dev, cmd, 0)) {
1282 			debug("%s: Could not reboot KBC\n", __func__);
1283 			return 1;
1284 		}
1285 	} else if (0 == strcmp("events", cmd)) {
1286 		uint32_t events;
1287 
1288 		if (cros_ec_get_host_events(dev, &events)) {
1289 			debug("%s: Could not read host events\n", __func__);
1290 			return 1;
1291 		}
1292 		printf("0x%08x\n", events);
1293 	} else if (0 == strcmp("clrevents", cmd)) {
1294 		uint32_t events = 0x7fffffff;
1295 
1296 		if (argc >= 3)
1297 			events = simple_strtol(argv[2], NULL, 0);
1298 
1299 		if (cros_ec_clear_host_events(dev, events)) {
1300 			debug("%s: Could not clear host events\n", __func__);
1301 			return 1;
1302 		}
1303 	} else if (0 == strcmp("read", cmd)) {
1304 		ret = do_read_write(dev, 0, argc, argv);
1305 		if (ret > 0)
1306 			return CMD_RET_USAGE;
1307 	} else if (0 == strcmp("write", cmd)) {
1308 		ret = do_read_write(dev, 1, argc, argv);
1309 		if (ret > 0)
1310 			return CMD_RET_USAGE;
1311 	} else if (0 == strcmp("erase", cmd)) {
1312 		int region = cros_ec_decode_region(argc - 2, argv + 2);
1313 		uint32_t offset, size;
1314 
1315 		if (region == -1)
1316 			return CMD_RET_USAGE;
1317 		if (cros_ec_flash_offset(dev, region, &offset, &size)) {
1318 			debug("%s: Could not read region info\n", __func__);
1319 			ret = -1;
1320 		} else {
1321 			ret = cros_ec_flash_erase(dev, offset, size);
1322 			if (ret) {
1323 				debug("%s: Could not erase region\n",
1324 				      __func__);
1325 			}
1326 		}
1327 	} else if (0 == strcmp("regioninfo", cmd)) {
1328 		int region = cros_ec_decode_region(argc - 2, argv + 2);
1329 		uint32_t offset, size;
1330 
1331 		if (region == -1)
1332 			return CMD_RET_USAGE;
1333 		ret = cros_ec_flash_offset(dev, region, &offset, &size);
1334 		if (ret) {
1335 			debug("%s: Could not read region info\n", __func__);
1336 		} else {
1337 			printf("Region: %s\n", region == EC_FLASH_REGION_RO ?
1338 					"RO" : "RW");
1339 			printf("Offset: %x\n", offset);
1340 			printf("Size:   %x\n", size);
1341 		}
1342 	} else if (0 == strcmp("vbnvcontext", cmd)) {
1343 		uint8_t block[EC_VBNV_BLOCK_SIZE];
1344 		char buf[3];
1345 		int i, len;
1346 		unsigned long result;
1347 
1348 		if (argc <= 2) {
1349 			ret = cros_ec_read_vbnvcontext(dev, block);
1350 			if (!ret) {
1351 				printf("vbnv_block: ");
1352 				for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++)
1353 					printf("%02x", block[i]);
1354 				putc('\n');
1355 			}
1356 		} else {
1357 			/*
1358 			 * TODO(clchiou): Move this to a utility function as
1359 			 * cmd_spi might want to call it.
1360 			 */
1361 			memset(block, 0, EC_VBNV_BLOCK_SIZE);
1362 			len = strlen(argv[2]);
1363 			buf[2] = '\0';
1364 			for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++) {
1365 				if (i * 2 >= len)
1366 					break;
1367 				buf[0] = argv[2][i * 2];
1368 				if (i * 2 + 1 >= len)
1369 					buf[1] = '0';
1370 				else
1371 					buf[1] = argv[2][i * 2 + 1];
1372 				strict_strtoul(buf, 16, &result);
1373 				block[i] = result;
1374 			}
1375 			ret = cros_ec_write_vbnvcontext(dev, block);
1376 		}
1377 		if (ret) {
1378 			debug("%s: Could not %s VbNvContext\n", __func__,
1379 					argc <= 2 ?  "read" : "write");
1380 		}
1381 	} else if (0 == strcmp("test", cmd)) {
1382 		int result = cros_ec_test(dev);
1383 
1384 		if (result)
1385 			printf("Test failed with error %d\n", result);
1386 		else
1387 			puts("Test passed\n");
1388 	} else if (0 == strcmp("version", cmd)) {
1389 		struct ec_response_get_version *p;
1390 		char *build_string;
1391 
1392 		ret = cros_ec_read_version(dev, &p);
1393 		if (!ret) {
1394 			/* Print versions */
1395 			printf("RO version:    %1.*s\n",
1396 			       (int)sizeof(p->version_string_ro),
1397 			       p->version_string_ro);
1398 			printf("RW version:    %1.*s\n",
1399 			       (int)sizeof(p->version_string_rw),
1400 			       p->version_string_rw);
1401 			printf("Firmware copy: %s\n",
1402 				(p->current_image <
1403 					ARRAY_SIZE(ec_current_image_name) ?
1404 				ec_current_image_name[p->current_image] :
1405 				"?"));
1406 			ret = cros_ec_read_build_info(dev, &build_string);
1407 			if (!ret)
1408 				printf("Build info:    %s\n", build_string);
1409 		}
1410 	} else if (0 == strcmp("ldo", cmd)) {
1411 		uint8_t index, state;
1412 		char *endp;
1413 
1414 		if (argc < 3)
1415 			return CMD_RET_USAGE;
1416 		index = simple_strtoul(argv[2], &endp, 10);
1417 		if (*argv[2] == 0 || *endp != 0)
1418 			return CMD_RET_USAGE;
1419 		if (argc > 3) {
1420 			state = simple_strtoul(argv[3], &endp, 10);
1421 			if (*argv[3] == 0 || *endp != 0)
1422 				return CMD_RET_USAGE;
1423 			ret = cros_ec_set_ldo(udev, index, state);
1424 		} else {
1425 			ret = cros_ec_get_ldo(udev, index, &state);
1426 			if (!ret) {
1427 				printf("LDO%d: %s\n", index,
1428 					state == EC_LDO_STATE_ON ?
1429 					"on" : "off");
1430 			}
1431 		}
1432 
1433 		if (ret) {
1434 			debug("%s: Could not access LDO%d\n", __func__, index);
1435 			return ret;
1436 		}
1437 	} else {
1438 		return CMD_RET_USAGE;
1439 	}
1440 
1441 	if (ret < 0) {
1442 		printf("Error: CROS-EC command failed (error %d)\n", ret);
1443 		ret = 1;
1444 	}
1445 
1446 	return ret;
1447 }
1448 
1449 int cros_ec_post_bind(struct udevice *dev)
1450 {
1451 	/* Scan for available EC devices (e.g. I2C tunnel) */
1452 	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
1453 }
1454 
1455 U_BOOT_CMD(
1456 	crosec,	6,	1,	do_cros_ec,
1457 	"CROS-EC utility command",
1458 	"init                Re-init CROS-EC (done on startup automatically)\n"
1459 	"crosec id                  Read CROS-EC ID\n"
1460 	"crosec info                Read CROS-EC info\n"
1461 	"crosec curimage            Read CROS-EC current image\n"
1462 	"crosec hash                Read CROS-EC hash\n"
1463 	"crosec reboot [rw | ro | cold]  Reboot CROS-EC\n"
1464 	"crosec events              Read CROS-EC host events\n"
1465 	"crosec clrevents [mask]    Clear CROS-EC host events\n"
1466 	"crosec regioninfo <ro|rw>  Read image info\n"
1467 	"crosec erase <ro|rw>       Erase EC image\n"
1468 	"crosec read <ro|rw> <addr> [<size>]   Read EC image\n"
1469 	"crosec write <ro|rw> <addr> [<size>]  Write EC image\n"
1470 	"crosec vbnvcontext [hexstring]        Read [write] VbNvContext from EC\n"
1471 	"crosec ldo <idx> [<state>] Switch/Read LDO state\n"
1472 	"crosec test                run tests on cros_ec\n"
1473 	"crosec version             Read CROS-EC version"
1474 );
1475 #endif
1476 
1477 UCLASS_DRIVER(cros_ec) = {
1478 	.id		= UCLASS_CROS_EC,
1479 	.name		= "cros_ec",
1480 	.per_device_auto_alloc_size = sizeof(struct cros_ec_dev),
1481 	.post_bind	= cros_ec_post_bind,
1482 };
1483