xref: /openbmc/u-boot/drivers/misc/cros_ec.c (revision 4381aad9)
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/uclass-internal.h>
30 
31 #ifdef DEBUG_TRACE
32 #define debug_trace(fmt, b...)	debug(fmt, #b)
33 #else
34 #define debug_trace(fmt, b...)
35 #endif
36 
37 enum {
38 	/* Timeout waiting for a flash erase command to complete */
39 	CROS_EC_CMD_TIMEOUT_MS	= 5000,
40 	/* Timeout waiting for a synchronous hash to be recomputed */
41 	CROS_EC_CMD_HASH_TIMEOUT_MS = 2000,
42 };
43 
44 #ifndef CONFIG_DM_CROS_EC
45 static struct cros_ec_dev static_dev, *last_dev;
46 #endif
47 
48 DECLARE_GLOBAL_DATA_PTR;
49 
50 /* Note: depends on enum ec_current_image */
51 static const char * const ec_current_image_name[] = {"unknown", "RO", "RW"};
52 
53 void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len)
54 {
55 #ifdef DEBUG
56 	int i;
57 
58 	printf("%s: ", name);
59 	if (cmd != -1)
60 		printf("cmd=%#x: ", cmd);
61 	for (i = 0; i < len; i++)
62 		printf("%02x ", data[i]);
63 	printf("\n");
64 #endif
65 }
66 
67 /*
68  * Calculate a simple 8-bit checksum of a data block
69  *
70  * @param data	Data block to checksum
71  * @param size	Size of data block in bytes
72  * @return checksum value (0 to 255)
73  */
74 int cros_ec_calc_checksum(const uint8_t *data, int size)
75 {
76 	int csum, i;
77 
78 	for (i = csum = 0; i < size; i++)
79 		csum += data[i];
80 	return csum & 0xff;
81 }
82 
83 /**
84  * Create a request packet for protocol version 3.
85  *
86  * The packet is stored in the device's internal output buffer.
87  *
88  * @param dev		CROS-EC device
89  * @param cmd		Command to send (EC_CMD_...)
90  * @param cmd_version	Version of command to send (EC_VER_...)
91  * @param dout          Output data (may be NULL If dout_len=0)
92  * @param dout_len      Size of output data in bytes
93  * @return packet size in bytes, or <0 if error.
94  */
95 static int create_proto3_request(struct cros_ec_dev *dev,
96 				 int cmd, int cmd_version,
97 				 const void *dout, int dout_len)
98 {
99 	struct ec_host_request *rq = (struct ec_host_request *)dev->dout;
100 	int out_bytes = dout_len + sizeof(*rq);
101 
102 	/* Fail if output size is too big */
103 	if (out_bytes > (int)sizeof(dev->dout)) {
104 		debug("%s: Cannot send %d bytes\n", __func__, dout_len);
105 		return -EC_RES_REQUEST_TRUNCATED;
106 	}
107 
108 	/* Fill in request packet */
109 	rq->struct_version = EC_HOST_REQUEST_VERSION;
110 	rq->checksum = 0;
111 	rq->command = cmd;
112 	rq->command_version = cmd_version;
113 	rq->reserved = 0;
114 	rq->data_len = dout_len;
115 
116 	/* Copy data after header */
117 	memcpy(rq + 1, dout, dout_len);
118 
119 	/* Write checksum field so the entire packet sums to 0 */
120 	rq->checksum = (uint8_t)(-cros_ec_calc_checksum(dev->dout, out_bytes));
121 
122 	cros_ec_dump_data("out", cmd, dev->dout, out_bytes);
123 
124 	/* Return size of request packet */
125 	return out_bytes;
126 }
127 
128 /**
129  * Prepare the device to receive a protocol version 3 response.
130  *
131  * @param dev		CROS-EC device
132  * @param din_len       Maximum size of response in bytes
133  * @return maximum expected number of bytes in response, or <0 if error.
134  */
135 static int prepare_proto3_response_buffer(struct cros_ec_dev *dev, int din_len)
136 {
137 	int in_bytes = din_len + sizeof(struct ec_host_response);
138 
139 	/* Fail if input size is too big */
140 	if (in_bytes > (int)sizeof(dev->din)) {
141 		debug("%s: Cannot receive %d bytes\n", __func__, din_len);
142 		return -EC_RES_RESPONSE_TOO_BIG;
143 	}
144 
145 	/* Return expected size of response packet */
146 	return in_bytes;
147 }
148 
149 /**
150  * Handle a protocol version 3 response packet.
151  *
152  * The packet must already be stored in the device's internal input buffer.
153  *
154  * @param dev		CROS-EC device
155  * @param dinp          Returns pointer to response data
156  * @param din_len       Maximum size of response in bytes
157  * @return number of bytes of response data, or <0 if error
158  */
159 static int handle_proto3_response(struct cros_ec_dev *dev,
160 				  uint8_t **dinp, int din_len)
161 {
162 	struct ec_host_response *rs = (struct ec_host_response *)dev->din;
163 	int in_bytes;
164 	int csum;
165 
166 	cros_ec_dump_data("in-header", -1, dev->din, sizeof(*rs));
167 
168 	/* Check input data */
169 	if (rs->struct_version != EC_HOST_RESPONSE_VERSION) {
170 		debug("%s: EC response version mismatch\n", __func__);
171 		return -EC_RES_INVALID_RESPONSE;
172 	}
173 
174 	if (rs->reserved) {
175 		debug("%s: EC response reserved != 0\n", __func__);
176 		return -EC_RES_INVALID_RESPONSE;
177 	}
178 
179 	if (rs->data_len > din_len) {
180 		debug("%s: EC returned too much data\n", __func__);
181 		return -EC_RES_RESPONSE_TOO_BIG;
182 	}
183 
184 	cros_ec_dump_data("in-data", -1, dev->din + sizeof(*rs), rs->data_len);
185 
186 	/* Update in_bytes to actual data size */
187 	in_bytes = sizeof(*rs) + rs->data_len;
188 
189 	/* Verify checksum */
190 	csum = cros_ec_calc_checksum(dev->din, in_bytes);
191 	if (csum) {
192 		debug("%s: EC response checksum invalid: 0x%02x\n", __func__,
193 		      csum);
194 		return -EC_RES_INVALID_CHECKSUM;
195 	}
196 
197 	/* Return error result, if any */
198 	if (rs->result)
199 		return -(int)rs->result;
200 
201 	/* If we're still here, set response data pointer and return length */
202 	*dinp = (uint8_t *)(rs + 1);
203 
204 	return rs->data_len;
205 }
206 
207 static int send_command_proto3(struct cros_ec_dev *dev,
208 			       int cmd, int cmd_version,
209 			       const void *dout, int dout_len,
210 			       uint8_t **dinp, int din_len)
211 {
212 #ifdef CONFIG_DM_CROS_EC
213 	struct dm_cros_ec_ops *ops;
214 #endif
215 	int out_bytes, in_bytes;
216 	int rv;
217 
218 	/* Create request packet */
219 	out_bytes = create_proto3_request(dev, cmd, cmd_version,
220 					  dout, dout_len);
221 	if (out_bytes < 0)
222 		return out_bytes;
223 
224 	/* Prepare response buffer */
225 	in_bytes = prepare_proto3_response_buffer(dev, din_len);
226 	if (in_bytes < 0)
227 		return in_bytes;
228 
229 #ifdef CONFIG_DM_CROS_EC
230 	ops = dm_cros_ec_get_ops(dev->dev);
231 	rv = ops->packet(dev->dev, out_bytes, in_bytes);
232 #else
233 	switch (dev->interface) {
234 #ifdef CONFIG_CROS_EC_SPI
235 	case CROS_EC_IF_SPI:
236 		rv = cros_ec_spi_packet(dev, out_bytes, in_bytes);
237 		break;
238 #endif
239 #ifdef CONFIG_CROS_EC_SANDBOX
240 	case CROS_EC_IF_SANDBOX:
241 		rv = cros_ec_sandbox_packet(dev, out_bytes, in_bytes);
242 		break;
243 #endif
244 	case CROS_EC_IF_NONE:
245 	/* TODO: support protocol 3 for LPC, I2C; for now fall through */
246 	default:
247 		debug("%s: Unsupported interface\n", __func__);
248 		rv = -1;
249 	}
250 #endif
251 	if (rv < 0)
252 		return rv;
253 
254 	/* Process the response */
255 	return handle_proto3_response(dev, dinp, din_len);
256 }
257 
258 static int send_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
259 			const void *dout, int dout_len,
260 			uint8_t **dinp, int din_len)
261 {
262 #ifdef CONFIG_DM_CROS_EC
263 	struct dm_cros_ec_ops *ops;
264 #endif
265 	int ret = -1;
266 
267 	/* Handle protocol version 3 support */
268 	if (dev->protocol_version == 3) {
269 		return send_command_proto3(dev, cmd, cmd_version,
270 					   dout, dout_len, dinp, din_len);
271 	}
272 
273 #ifdef CONFIG_DM_CROS_EC
274 	ops = dm_cros_ec_get_ops(dev->dev);
275 	ret = ops->command(dev->dev, cmd, cmd_version,
276 			   (const uint8_t *)dout, dout_len, dinp, din_len);
277 #else
278 	switch (dev->interface) {
279 #ifdef CONFIG_CROS_EC_SPI
280 	case CROS_EC_IF_SPI:
281 		ret = cros_ec_spi_command(dev, cmd, cmd_version,
282 					(const uint8_t *)dout, dout_len,
283 					dinp, din_len);
284 		break;
285 #endif
286 #ifdef CONFIG_CROS_EC_I2C
287 	case CROS_EC_IF_I2C:
288 		ret = cros_ec_i2c_command(dev, cmd, cmd_version,
289 					(const uint8_t *)dout, dout_len,
290 					dinp, din_len);
291 		break;
292 #endif
293 #ifdef CONFIG_CROS_EC_LPC
294 	case CROS_EC_IF_LPC:
295 		ret = cros_ec_lpc_command(dev, cmd, cmd_version,
296 					(const uint8_t *)dout, dout_len,
297 					dinp, din_len);
298 		break;
299 #endif
300 	case CROS_EC_IF_NONE:
301 	default:
302 		ret = -1;
303 	}
304 #endif
305 
306 	return ret;
307 }
308 
309 /**
310  * Send a command to the CROS-EC device and return the reply.
311  *
312  * The device's internal input/output buffers are used.
313  *
314  * @param dev		CROS-EC device
315  * @param cmd		Command to send (EC_CMD_...)
316  * @param cmd_version	Version of command to send (EC_VER_...)
317  * @param dout          Output data (may be NULL If dout_len=0)
318  * @param dout_len      Size of output data in bytes
319  * @param dinp          Response data (may be NULL If din_len=0).
320  *			If not NULL, it will be updated to point to the data
321  *			and will always be double word aligned (64-bits)
322  * @param din_len       Maximum size of response in bytes
323  * @return number of bytes in response, or -1 on error
324  */
325 static int ec_command_inptr(struct cros_ec_dev *dev, uint8_t cmd,
326 		int cmd_version, const void *dout, int dout_len, uint8_t **dinp,
327 		int din_len)
328 {
329 	uint8_t *din = NULL;
330 	int len;
331 
332 	len = send_command(dev, cmd, cmd_version, dout, dout_len,
333 				&din, din_len);
334 
335 	/* If the command doesn't complete, wait a while */
336 	if (len == -EC_RES_IN_PROGRESS) {
337 		struct ec_response_get_comms_status *resp = NULL;
338 		ulong start;
339 
340 		/* Wait for command to complete */
341 		start = get_timer(0);
342 		do {
343 			int ret;
344 
345 			mdelay(50);	/* Insert some reasonable delay */
346 			ret = send_command(dev, EC_CMD_GET_COMMS_STATUS, 0,
347 					NULL, 0,
348 					(uint8_t **)&resp, sizeof(*resp));
349 			if (ret < 0)
350 				return ret;
351 
352 			if (get_timer(start) > CROS_EC_CMD_TIMEOUT_MS) {
353 				debug("%s: Command %#02x timeout\n",
354 				      __func__, cmd);
355 				return -EC_RES_TIMEOUT;
356 			}
357 		} while (resp->flags & EC_COMMS_STATUS_PROCESSING);
358 
359 		/* OK it completed, so read the status response */
360 		/* not sure why it was 0 for the last argument */
361 		len = send_command(dev, EC_CMD_RESEND_RESPONSE, 0,
362 				NULL, 0, &din, din_len);
363 	}
364 
365 	debug("%s: len=%d, dinp=%p, *dinp=%p\n", __func__, len, dinp,
366 	      dinp ? *dinp : NULL);
367 	if (dinp) {
368 		/* If we have any data to return, it must be 64bit-aligned */
369 		assert(len <= 0 || !((uintptr_t)din & 7));
370 		*dinp = din;
371 	}
372 
373 	return len;
374 }
375 
376 /**
377  * Send a command to the CROS-EC device and return the reply.
378  *
379  * The device's internal input/output buffers are used.
380  *
381  * @param dev		CROS-EC device
382  * @param cmd		Command to send (EC_CMD_...)
383  * @param cmd_version	Version of command to send (EC_VER_...)
384  * @param dout          Output data (may be NULL If dout_len=0)
385  * @param dout_len      Size of output data in bytes
386  * @param din           Response data (may be NULL If din_len=0).
387  *			It not NULL, it is a place for ec_command() to copy the
388  *      data to.
389  * @param din_len       Maximum size of response in bytes
390  * @return number of bytes in response, or -1 on error
391  */
392 static int ec_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
393 		      const void *dout, int dout_len,
394 		      void *din, int din_len)
395 {
396 	uint8_t *in_buffer;
397 	int len;
398 
399 	assert((din_len == 0) || din);
400 	len = ec_command_inptr(dev, cmd, cmd_version, dout, dout_len,
401 			&in_buffer, din_len);
402 	if (len > 0) {
403 		/*
404 		 * If we were asked to put it somewhere, do so, otherwise just
405 		 * disregard the result.
406 		 */
407 		if (din && in_buffer) {
408 			assert(len <= din_len);
409 			memmove(din, in_buffer, len);
410 		}
411 	}
412 	return len;
413 }
414 
415 int cros_ec_scan_keyboard(struct cros_ec_dev *dev, struct mbkp_keyscan *scan)
416 {
417 	if (ec_command(dev, EC_CMD_MKBP_STATE, 0, NULL, 0, scan,
418 		       sizeof(scan->data)) != sizeof(scan->data))
419 		return -1;
420 
421 	return 0;
422 }
423 
424 int cros_ec_read_id(struct cros_ec_dev *dev, char *id, int maxlen)
425 {
426 	struct ec_response_get_version *r;
427 
428 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
429 			(uint8_t **)&r, sizeof(*r)) != sizeof(*r))
430 		return -1;
431 
432 	if (maxlen > (int)sizeof(r->version_string_ro))
433 		maxlen = sizeof(r->version_string_ro);
434 
435 	switch (r->current_image) {
436 	case EC_IMAGE_RO:
437 		memcpy(id, r->version_string_ro, maxlen);
438 		break;
439 	case EC_IMAGE_RW:
440 		memcpy(id, r->version_string_rw, maxlen);
441 		break;
442 	default:
443 		return -1;
444 	}
445 
446 	id[maxlen - 1] = '\0';
447 	return 0;
448 }
449 
450 int cros_ec_read_version(struct cros_ec_dev *dev,
451 		       struct ec_response_get_version **versionp)
452 {
453 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
454 			(uint8_t **)versionp, sizeof(**versionp))
455 			!= sizeof(**versionp))
456 		return -1;
457 
458 	return 0;
459 }
460 
461 int cros_ec_read_build_info(struct cros_ec_dev *dev, char **strp)
462 {
463 	if (ec_command_inptr(dev, EC_CMD_GET_BUILD_INFO, 0, NULL, 0,
464 			(uint8_t **)strp, EC_PROTO2_MAX_PARAM_SIZE) < 0)
465 		return -1;
466 
467 	return 0;
468 }
469 
470 int cros_ec_read_current_image(struct cros_ec_dev *dev,
471 		enum ec_current_image *image)
472 {
473 	struct ec_response_get_version *r;
474 
475 	if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
476 			(uint8_t **)&r, sizeof(*r)) != sizeof(*r))
477 		return -1;
478 
479 	*image = r->current_image;
480 	return 0;
481 }
482 
483 static int cros_ec_wait_on_hash_done(struct cros_ec_dev *dev,
484 				  struct ec_response_vboot_hash *hash)
485 {
486 	struct ec_params_vboot_hash p;
487 	ulong start;
488 
489 	start = get_timer(0);
490 	while (hash->status == EC_VBOOT_HASH_STATUS_BUSY) {
491 		mdelay(50);	/* Insert some reasonable delay */
492 
493 		p.cmd = EC_VBOOT_HASH_GET;
494 		if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
495 		       hash, sizeof(*hash)) < 0)
496 			return -1;
497 
498 		if (get_timer(start) > CROS_EC_CMD_HASH_TIMEOUT_MS) {
499 			debug("%s: EC_VBOOT_HASH_GET timeout\n", __func__);
500 			return -EC_RES_TIMEOUT;
501 		}
502 	}
503 	return 0;
504 }
505 
506 
507 int cros_ec_read_hash(struct cros_ec_dev *dev,
508 		struct ec_response_vboot_hash *hash)
509 {
510 	struct ec_params_vboot_hash p;
511 	int rv;
512 
513 	p.cmd = EC_VBOOT_HASH_GET;
514 	if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
515 		       hash, sizeof(*hash)) < 0)
516 		return -1;
517 
518 	/* If the EC is busy calculating the hash, fidget until it's done. */
519 	rv = cros_ec_wait_on_hash_done(dev, hash);
520 	if (rv)
521 		return rv;
522 
523 	/* If the hash is valid, we're done. Otherwise, we have to kick it off
524 	 * again and wait for it to complete. Note that we explicitly assume
525 	 * that hashing zero bytes is always wrong, even though that would
526 	 * produce a valid hash value. */
527 	if (hash->status == EC_VBOOT_HASH_STATUS_DONE && hash->size)
528 		return 0;
529 
530 	debug("%s: No valid hash (status=%d size=%d). Compute one...\n",
531 	      __func__, hash->status, hash->size);
532 
533 	p.cmd = EC_VBOOT_HASH_START;
534 	p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
535 	p.nonce_size = 0;
536 	p.offset = EC_VBOOT_HASH_OFFSET_RW;
537 
538 	if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
539 		       hash, sizeof(*hash)) < 0)
540 		return -1;
541 
542 	rv = cros_ec_wait_on_hash_done(dev, hash);
543 	if (rv)
544 		return rv;
545 
546 	debug("%s: hash done\n", __func__);
547 
548 	return 0;
549 }
550 
551 static int cros_ec_invalidate_hash(struct cros_ec_dev *dev)
552 {
553 	struct ec_params_vboot_hash p;
554 	struct ec_response_vboot_hash *hash;
555 
556 	/* We don't have an explict command for the EC to discard its current
557 	 * hash value, so we'll just tell it to calculate one that we know is
558 	 * wrong (we claim that hashing zero bytes is always invalid).
559 	 */
560 	p.cmd = EC_VBOOT_HASH_RECALC;
561 	p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
562 	p.nonce_size = 0;
563 	p.offset = 0;
564 	p.size = 0;
565 
566 	debug("%s:\n", __func__);
567 
568 	if (ec_command_inptr(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
569 		       (uint8_t **)&hash, sizeof(*hash)) < 0)
570 		return -1;
571 
572 	/* No need to wait for it to finish */
573 	return 0;
574 }
575 
576 int cros_ec_reboot(struct cros_ec_dev *dev, enum ec_reboot_cmd cmd,
577 		uint8_t flags)
578 {
579 	struct ec_params_reboot_ec p;
580 
581 	p.cmd = cmd;
582 	p.flags = flags;
583 
584 	if (ec_command_inptr(dev, EC_CMD_REBOOT_EC, 0, &p, sizeof(p), NULL, 0)
585 			< 0)
586 		return -1;
587 
588 	if (!(flags & EC_REBOOT_FLAG_ON_AP_SHUTDOWN)) {
589 		/*
590 		 * EC reboot will take place immediately so delay to allow it
591 		 * to complete.  Note that some reboot types (EC_REBOOT_COLD)
592 		 * will reboot the AP as well, in which case we won't actually
593 		 * get to this point.
594 		 */
595 		/*
596 		 * TODO(rspangler@chromium.org): Would be nice if we had a
597 		 * better way to determine when the reboot is complete.  Could
598 		 * we poll a memory-mapped LPC value?
599 		 */
600 		udelay(50000);
601 	}
602 
603 	return 0;
604 }
605 
606 int cros_ec_interrupt_pending(struct cros_ec_dev *dev)
607 {
608 	/* no interrupt support : always poll */
609 	if (!fdt_gpio_isvalid(&dev->ec_int))
610 		return -ENOENT;
611 
612 	return !gpio_get_value(dev->ec_int.gpio);
613 }
614 
615 int cros_ec_info(struct cros_ec_dev *dev, struct ec_response_mkbp_info *info)
616 {
617 	if (ec_command(dev, EC_CMD_MKBP_INFO, 0, NULL, 0, info,
618 		       sizeof(*info)) != sizeof(*info))
619 		return -1;
620 
621 	return 0;
622 }
623 
624 int cros_ec_get_host_events(struct cros_ec_dev *dev, uint32_t *events_ptr)
625 {
626 	struct ec_response_host_event_mask *resp;
627 
628 	/*
629 	 * Use the B copy of the event flags, because the main copy is already
630 	 * used by ACPI/SMI.
631 	 */
632 	if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_GET_B, 0, NULL, 0,
633 		       (uint8_t **)&resp, sizeof(*resp)) < (int)sizeof(*resp))
634 		return -1;
635 
636 	if (resp->mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INVALID))
637 		return -1;
638 
639 	*events_ptr = resp->mask;
640 	return 0;
641 }
642 
643 int cros_ec_clear_host_events(struct cros_ec_dev *dev, uint32_t events)
644 {
645 	struct ec_params_host_event_mask params;
646 
647 	params.mask = events;
648 
649 	/*
650 	 * Use the B copy of the event flags, so it affects the data returned
651 	 * by cros_ec_get_host_events().
652 	 */
653 	if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_CLEAR_B, 0,
654 		       &params, sizeof(params), NULL, 0) < 0)
655 		return -1;
656 
657 	return 0;
658 }
659 
660 int cros_ec_flash_protect(struct cros_ec_dev *dev,
661 		       uint32_t set_mask, uint32_t set_flags,
662 		       struct ec_response_flash_protect *resp)
663 {
664 	struct ec_params_flash_protect params;
665 
666 	params.mask = set_mask;
667 	params.flags = set_flags;
668 
669 	if (ec_command(dev, EC_CMD_FLASH_PROTECT, EC_VER_FLASH_PROTECT,
670 		       &params, sizeof(params),
671 		       resp, sizeof(*resp)) != sizeof(*resp))
672 		return -1;
673 
674 	return 0;
675 }
676 
677 static int cros_ec_check_version(struct cros_ec_dev *dev)
678 {
679 	struct ec_params_hello req;
680 	struct ec_response_hello *resp;
681 
682 #ifdef CONFIG_CROS_EC_LPC
683 	/* LPC has its own way of doing this */
684 	if (dev->interface == CROS_EC_IF_LPC)
685 		return cros_ec_lpc_check_version(dev);
686 #endif
687 
688 	/*
689 	 * TODO(sjg@chromium.org).
690 	 * There is a strange oddity here with the EC. We could just ignore
691 	 * the response, i.e. pass the last two parameters as NULL and 0.
692 	 * In this case we won't read back very many bytes from the EC.
693 	 * On the I2C bus the EC gets upset about this and will try to send
694 	 * the bytes anyway. This means that we will have to wait for that
695 	 * to complete before continuing with a new EC command.
696 	 *
697 	 * This problem is probably unique to the I2C bus.
698 	 *
699 	 * So for now, just read all the data anyway.
700 	 */
701 
702 	/* Try sending a version 3 packet */
703 	dev->protocol_version = 3;
704 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
705 			     (uint8_t **)&resp, sizeof(*resp)) > 0) {
706 		return 0;
707 	}
708 
709 	/* Try sending a version 2 packet */
710 	dev->protocol_version = 2;
711 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
712 		       (uint8_t **)&resp, sizeof(*resp)) > 0) {
713 		return 0;
714 	}
715 
716 	/*
717 	 * Fail if we're still here, since the EC doesn't understand any
718 	 * protcol version we speak.  Version 1 interface without command
719 	 * version is no longer supported, and we don't know about any new
720 	 * protocol versions.
721 	 */
722 	dev->protocol_version = 0;
723 	printf("%s: ERROR: old EC interface not supported\n", __func__);
724 	return -1;
725 }
726 
727 int cros_ec_test(struct cros_ec_dev *dev)
728 {
729 	struct ec_params_hello req;
730 	struct ec_response_hello *resp;
731 
732 	req.in_data = 0x12345678;
733 	if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
734 		       (uint8_t **)&resp, sizeof(*resp)) < sizeof(*resp)) {
735 		printf("ec_command_inptr() returned error\n");
736 		return -1;
737 	}
738 	if (resp->out_data != req.in_data + 0x01020304) {
739 		printf("Received invalid handshake %x\n", resp->out_data);
740 		return -1;
741 	}
742 
743 	return 0;
744 }
745 
746 int cros_ec_flash_offset(struct cros_ec_dev *dev, enum ec_flash_region region,
747 		      uint32_t *offset, uint32_t *size)
748 {
749 	struct ec_params_flash_region_info p;
750 	struct ec_response_flash_region_info *r;
751 	int ret;
752 
753 	p.region = region;
754 	ret = ec_command_inptr(dev, EC_CMD_FLASH_REGION_INFO,
755 			 EC_VER_FLASH_REGION_INFO,
756 			 &p, sizeof(p), (uint8_t **)&r, sizeof(*r));
757 	if (ret != sizeof(*r))
758 		return -1;
759 
760 	if (offset)
761 		*offset = r->offset;
762 	if (size)
763 		*size = r->size;
764 
765 	return 0;
766 }
767 
768 int cros_ec_flash_erase(struct cros_ec_dev *dev, uint32_t offset, uint32_t size)
769 {
770 	struct ec_params_flash_erase p;
771 
772 	p.offset = offset;
773 	p.size = size;
774 	return ec_command_inptr(dev, EC_CMD_FLASH_ERASE, 0, &p, sizeof(p),
775 			NULL, 0);
776 }
777 
778 /**
779  * Write a single block to the flash
780  *
781  * Write a block of data to the EC flash. The size must not exceed the flash
782  * write block size which you can obtain from cros_ec_flash_write_burst_size().
783  *
784  * The offset starts at 0. You can obtain the region information from
785  * cros_ec_flash_offset() to find out where to write for a particular region.
786  *
787  * Attempting to write to the region where the EC is currently running from
788  * will result in an error.
789  *
790  * @param dev		CROS-EC device
791  * @param data		Pointer to data buffer to write
792  * @param offset	Offset within flash to write to.
793  * @param size		Number of bytes to write
794  * @return 0 if ok, -1 on error
795  */
796 static int cros_ec_flash_write_block(struct cros_ec_dev *dev,
797 		const uint8_t *data, uint32_t offset, uint32_t size)
798 {
799 	struct ec_params_flash_write p;
800 
801 	p.offset = offset;
802 	p.size = size;
803 	assert(data && p.size <= EC_FLASH_WRITE_VER0_SIZE);
804 	memcpy(&p + 1, data, p.size);
805 
806 	return ec_command_inptr(dev, EC_CMD_FLASH_WRITE, 0,
807 			  &p, sizeof(p), NULL, 0) >= 0 ? 0 : -1;
808 }
809 
810 /**
811  * Return optimal flash write burst size
812  */
813 static int cros_ec_flash_write_burst_size(struct cros_ec_dev *dev)
814 {
815 	return EC_FLASH_WRITE_VER0_SIZE;
816 }
817 
818 /**
819  * Check if a block of data is erased (all 0xff)
820  *
821  * This function is useful when dealing with flash, for checking whether a
822  * data block is erased and thus does not need to be programmed.
823  *
824  * @param data		Pointer to data to check (must be word-aligned)
825  * @param size		Number of bytes to check (must be word-aligned)
826  * @return 0 if erased, non-zero if any word is not erased
827  */
828 static int cros_ec_data_is_erased(const uint32_t *data, int size)
829 {
830 	assert(!(size & 3));
831 	size /= sizeof(uint32_t);
832 	for (; size > 0; size -= 4, data++)
833 		if (*data != -1U)
834 			return 0;
835 
836 	return 1;
837 }
838 
839 int cros_ec_flash_write(struct cros_ec_dev *dev, const uint8_t *data,
840 		     uint32_t offset, uint32_t size)
841 {
842 	uint32_t burst = cros_ec_flash_write_burst_size(dev);
843 	uint32_t end, off;
844 	int ret;
845 
846 	/*
847 	 * TODO: round up to the nearest multiple of write size.  Can get away
848 	 * without that on link right now because its write size is 4 bytes.
849 	 */
850 	end = offset + size;
851 	for (off = offset; off < end; off += burst, data += burst) {
852 		uint32_t todo;
853 
854 		/* If the data is empty, there is no point in programming it */
855 		todo = min(end - off, burst);
856 		if (dev->optimise_flash_write &&
857 				cros_ec_data_is_erased((uint32_t *)data, todo))
858 			continue;
859 
860 		ret = cros_ec_flash_write_block(dev, data, off, todo);
861 		if (ret)
862 			return ret;
863 	}
864 
865 	return 0;
866 }
867 
868 /**
869  * Read a single block from the flash
870  *
871  * Read a block of data from the EC flash. The size must not exceed the flash
872  * write block size which you can obtain from cros_ec_flash_write_burst_size().
873  *
874  * The offset starts at 0. You can obtain the region information from
875  * cros_ec_flash_offset() to find out where to read for a particular region.
876  *
877  * @param dev		CROS-EC device
878  * @param data		Pointer to data buffer to read into
879  * @param offset	Offset within flash to read from
880  * @param size		Number of bytes to read
881  * @return 0 if ok, -1 on error
882  */
883 static int cros_ec_flash_read_block(struct cros_ec_dev *dev, uint8_t *data,
884 				 uint32_t offset, uint32_t size)
885 {
886 	struct ec_params_flash_read p;
887 
888 	p.offset = offset;
889 	p.size = size;
890 
891 	return ec_command(dev, EC_CMD_FLASH_READ, 0,
892 			  &p, sizeof(p), data, size) >= 0 ? 0 : -1;
893 }
894 
895 int cros_ec_flash_read(struct cros_ec_dev *dev, uint8_t *data, uint32_t offset,
896 		    uint32_t size)
897 {
898 	uint32_t burst = cros_ec_flash_write_burst_size(dev);
899 	uint32_t end, off;
900 	int ret;
901 
902 	end = offset + size;
903 	for (off = offset; off < end; off += burst, data += burst) {
904 		ret = cros_ec_flash_read_block(dev, data, off,
905 					    min(end - off, burst));
906 		if (ret)
907 			return ret;
908 	}
909 
910 	return 0;
911 }
912 
913 int cros_ec_flash_update_rw(struct cros_ec_dev *dev,
914 			 const uint8_t *image, int image_size)
915 {
916 	uint32_t rw_offset, rw_size;
917 	int ret;
918 
919 	if (cros_ec_flash_offset(dev, EC_FLASH_REGION_RW, &rw_offset, &rw_size))
920 		return -1;
921 	if (image_size > (int)rw_size)
922 		return -1;
923 
924 	/* Invalidate the existing hash, just in case the AP reboots
925 	 * unexpectedly during the update. If that happened, the EC RW firmware
926 	 * would be invalid, but the EC would still have the original hash.
927 	 */
928 	ret = cros_ec_invalidate_hash(dev);
929 	if (ret)
930 		return ret;
931 
932 	/*
933 	 * Erase the entire RW section, so that the EC doesn't see any garbage
934 	 * past the new image if it's smaller than the current image.
935 	 *
936 	 * TODO: could optimize this to erase just the current image, since
937 	 * presumably everything past that is 0xff's.  But would still need to
938 	 * round up to the nearest multiple of erase size.
939 	 */
940 	ret = cros_ec_flash_erase(dev, rw_offset, rw_size);
941 	if (ret)
942 		return ret;
943 
944 	/* Write the image */
945 	ret = cros_ec_flash_write(dev, image, rw_offset, image_size);
946 	if (ret)
947 		return ret;
948 
949 	return 0;
950 }
951 
952 int cros_ec_read_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block)
953 {
954 	struct ec_params_vbnvcontext p;
955 	int len;
956 
957 	p.op = EC_VBNV_CONTEXT_OP_READ;
958 
959 	len = ec_command(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
960 			&p, sizeof(p), block, EC_VBNV_BLOCK_SIZE);
961 	if (len < EC_VBNV_BLOCK_SIZE)
962 		return -1;
963 
964 	return 0;
965 }
966 
967 int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block)
968 {
969 	struct ec_params_vbnvcontext p;
970 	int len;
971 
972 	p.op = EC_VBNV_CONTEXT_OP_WRITE;
973 	memcpy(p.block, block, sizeof(p.block));
974 
975 	len = ec_command_inptr(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
976 			&p, sizeof(p), NULL, 0);
977 	if (len < 0)
978 		return -1;
979 
980 	return 0;
981 }
982 
983 int cros_ec_set_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t state)
984 {
985 	struct ec_params_ldo_set params;
986 
987 	params.index = index;
988 	params.state = state;
989 
990 	if (ec_command_inptr(dev, EC_CMD_LDO_SET, 0,
991 		       &params, sizeof(params),
992 		       NULL, 0))
993 		return -1;
994 
995 	return 0;
996 }
997 
998 int cros_ec_get_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t *state)
999 {
1000 	struct ec_params_ldo_get params;
1001 	struct ec_response_ldo_get *resp;
1002 
1003 	params.index = index;
1004 
1005 	if (ec_command_inptr(dev, EC_CMD_LDO_GET, 0,
1006 		       &params, sizeof(params),
1007 		       (uint8_t **)&resp, sizeof(*resp)) != sizeof(*resp))
1008 		return -1;
1009 
1010 	*state = resp->state;
1011 
1012 	return 0;
1013 }
1014 
1015 #ifndef CONFIG_DM_CROS_EC
1016 /**
1017  * Decode EC interface details from the device tree and allocate a suitable
1018  * device.
1019  *
1020  * @param blob		Device tree blob
1021  * @param node		Node to decode from
1022  * @param devp		Returns a pointer to the new allocated device
1023  * @return 0 if ok, -1 on error
1024  */
1025 static int cros_ec_decode_fdt(const void *blob, int node,
1026 		struct cros_ec_dev **devp)
1027 {
1028 	enum fdt_compat_id compat;
1029 	struct cros_ec_dev *dev;
1030 	int parent;
1031 
1032 	/* See what type of parent we are inside (this is expensive) */
1033 	parent = fdt_parent_offset(blob, node);
1034 	if (parent < 0) {
1035 		debug("%s: Cannot find node parent\n", __func__);
1036 		return -1;
1037 	}
1038 
1039 	dev = &static_dev;
1040 	dev->node = node;
1041 	dev->parent_node = parent;
1042 
1043 	compat = fdtdec_lookup(blob, parent);
1044 	switch (compat) {
1045 #ifdef CONFIG_CROS_EC_SPI
1046 	case COMPAT_SAMSUNG_EXYNOS_SPI:
1047 		dev->interface = CROS_EC_IF_SPI;
1048 		if (cros_ec_spi_decode_fdt(dev, blob))
1049 			return -1;
1050 		break;
1051 #endif
1052 #ifdef CONFIG_CROS_EC_I2C
1053 	case COMPAT_SAMSUNG_S3C2440_I2C:
1054 		dev->interface = CROS_EC_IF_I2C;
1055 		if (cros_ec_i2c_decode_fdt(dev, blob))
1056 			return -1;
1057 		break;
1058 #endif
1059 #ifdef CONFIG_CROS_EC_LPC
1060 	case COMPAT_INTEL_LPC:
1061 		dev->interface = CROS_EC_IF_LPC;
1062 		break;
1063 #endif
1064 #ifdef CONFIG_CROS_EC_SANDBOX
1065 	case COMPAT_SANDBOX_HOST_EMULATION:
1066 		dev->interface = CROS_EC_IF_SANDBOX;
1067 		break;
1068 #endif
1069 	default:
1070 		debug("%s: Unknown compat id %d\n", __func__, compat);
1071 		return -1;
1072 	}
1073 
1074 	fdtdec_decode_gpio(blob, node, "ec-interrupt", &dev->ec_int);
1075 	dev->optimise_flash_write = fdtdec_get_bool(blob, node,
1076 						    "optimise-flash-write");
1077 	*devp = dev;
1078 
1079 	return 0;
1080 }
1081 #endif
1082 
1083 #ifdef CONFIG_DM_CROS_EC
1084 int cros_ec_register(struct udevice *dev)
1085 {
1086 	struct cros_ec_dev *cdev = dev->uclass_priv;
1087 	const void *blob = gd->fdt_blob;
1088 	int node = dev->of_offset;
1089 	char id[MSG_BYTES];
1090 
1091 	cdev->dev = dev;
1092 	fdtdec_decode_gpio(blob, node, "ec-interrupt", &cdev->ec_int);
1093 	cdev->optimise_flash_write = fdtdec_get_bool(blob, node,
1094 						     "optimise-flash-write");
1095 
1096 	/* we will poll the EC interrupt line */
1097 	fdtdec_setup_gpio(&cdev->ec_int);
1098 	if (fdt_gpio_isvalid(&cdev->ec_int)) {
1099 		gpio_request(cdev->ec_int.gpio, "cros-ec-irq");
1100 		gpio_direction_input(cdev->ec_int.gpio);
1101 	}
1102 
1103 	if (cros_ec_check_version(cdev)) {
1104 		debug("%s: Could not detect CROS-EC version\n", __func__);
1105 		return -CROS_EC_ERR_CHECK_VERSION;
1106 	}
1107 
1108 	if (cros_ec_read_id(cdev, id, sizeof(id))) {
1109 		debug("%s: Could not read KBC ID\n", __func__);
1110 		return -CROS_EC_ERR_READ_ID;
1111 	}
1112 
1113 	/* Remember this device for use by the cros_ec command */
1114 	debug("Google Chrome EC CROS-EC driver ready, id '%s'\n", id);
1115 
1116 	return 0;
1117 }
1118 #else
1119 int cros_ec_init(const void *blob, struct cros_ec_dev **cros_ecp)
1120 {
1121 	struct cros_ec_dev *dev;
1122 	char id[MSG_BYTES];
1123 #ifdef CONFIG_DM_CROS_EC
1124 	struct udevice *udev;
1125 	int ret;
1126 
1127 	ret = uclass_find_device(UCLASS_CROS_EC, 0, &udev);
1128 	if (!ret)
1129 		device_remove(udev);
1130 	ret = uclass_get_device(UCLASS_CROS_EC, 0, &udev);
1131 	if (ret)
1132 		return ret;
1133 	dev = udev->uclass_priv;
1134 	return 0;
1135 #else
1136 	int node = 0;
1137 
1138 	*cros_ecp = NULL;
1139 	do {
1140 		node = fdtdec_next_compatible(blob, node,
1141 					      COMPAT_GOOGLE_CROS_EC);
1142 		if (node < 0) {
1143 			debug("%s: Node not found\n", __func__);
1144 			return 0;
1145 		}
1146 	} while (!fdtdec_get_is_enabled(blob, node));
1147 
1148 	if (cros_ec_decode_fdt(blob, node, &dev)) {
1149 		debug("%s: Failed to decode device.\n", __func__);
1150 		return -CROS_EC_ERR_FDT_DECODE;
1151 	}
1152 
1153 	switch (dev->interface) {
1154 #ifdef CONFIG_CROS_EC_SPI
1155 	case CROS_EC_IF_SPI:
1156 		if (cros_ec_spi_init(dev, blob)) {
1157 			debug("%s: Could not setup SPI interface\n", __func__);
1158 			return -CROS_EC_ERR_DEV_INIT;
1159 		}
1160 		break;
1161 #endif
1162 #ifdef CONFIG_CROS_EC_I2C
1163 	case CROS_EC_IF_I2C:
1164 		if (cros_ec_i2c_init(dev, blob))
1165 			return -CROS_EC_ERR_DEV_INIT;
1166 		break;
1167 #endif
1168 #ifdef CONFIG_CROS_EC_LPC
1169 	case CROS_EC_IF_LPC:
1170 		if (cros_ec_lpc_init(dev, blob))
1171 			return -CROS_EC_ERR_DEV_INIT;
1172 		break;
1173 #endif
1174 #ifdef CONFIG_CROS_EC_SANDBOX
1175 	case CROS_EC_IF_SANDBOX:
1176 		if (cros_ec_sandbox_init(dev, blob))
1177 			return -CROS_EC_ERR_DEV_INIT;
1178 		break;
1179 #endif
1180 	case CROS_EC_IF_NONE:
1181 	default:
1182 		return 0;
1183 	}
1184 #endif
1185 
1186 	/* we will poll the EC interrupt line */
1187 	fdtdec_setup_gpio(&dev->ec_int);
1188 	if (fdt_gpio_isvalid(&dev->ec_int)) {
1189 		gpio_request(dev->ec_int.gpio, "cros-ec-irq");
1190 		gpio_direction_input(dev->ec_int.gpio);
1191 	}
1192 
1193 	if (cros_ec_check_version(dev)) {
1194 		debug("%s: Could not detect CROS-EC version\n", __func__);
1195 		return -CROS_EC_ERR_CHECK_VERSION;
1196 	}
1197 
1198 	if (cros_ec_read_id(dev, id, sizeof(id))) {
1199 		debug("%s: Could not read KBC ID\n", __func__);
1200 		return -CROS_EC_ERR_READ_ID;
1201 	}
1202 
1203 	/* Remember this device for use by the cros_ec command */
1204 	*cros_ecp = dev;
1205 #ifndef CONFIG_DM_CROS_EC
1206 	last_dev = dev;
1207 #endif
1208 	debug("Google Chrome EC CROS-EC driver ready, id '%s'\n", id);
1209 
1210 	return 0;
1211 }
1212 #endif
1213 
1214 int cros_ec_decode_region(int argc, char * const argv[])
1215 {
1216 	if (argc > 0) {
1217 		if (0 == strcmp(*argv, "rw"))
1218 			return EC_FLASH_REGION_RW;
1219 		else if (0 == strcmp(*argv, "ro"))
1220 			return EC_FLASH_REGION_RO;
1221 
1222 		debug("%s: Invalid region '%s'\n", __func__, *argv);
1223 	} else {
1224 		debug("%s: Missing region parameter\n", __func__);
1225 	}
1226 
1227 	return -1;
1228 }
1229 
1230 int cros_ec_decode_ec_flash(const void *blob, int node,
1231 			    struct fdt_cros_ec *config)
1232 {
1233 	int flash_node;
1234 
1235 	flash_node = fdt_subnode_offset(blob, node, "flash");
1236 	if (flash_node < 0) {
1237 		debug("Failed to find flash node\n");
1238 		return -1;
1239 	}
1240 
1241 	if (fdtdec_read_fmap_entry(blob, flash_node, "flash",
1242 				   &config->flash)) {
1243 		debug("Failed to decode flash node in chrome-ec'\n");
1244 		return -1;
1245 	}
1246 
1247 	config->flash_erase_value = fdtdec_get_int(blob, flash_node,
1248 						    "erase-value", -1);
1249 	for (node = fdt_first_subnode(blob, flash_node); node >= 0;
1250 	     node = fdt_next_subnode(blob, node)) {
1251 		const char *name = fdt_get_name(blob, node, NULL);
1252 		enum ec_flash_region region;
1253 
1254 		if (0 == strcmp(name, "ro")) {
1255 			region = EC_FLASH_REGION_RO;
1256 		} else if (0 == strcmp(name, "rw")) {
1257 			region = EC_FLASH_REGION_RW;
1258 		} else if (0 == strcmp(name, "wp-ro")) {
1259 			region = EC_FLASH_REGION_WP_RO;
1260 		} else {
1261 			debug("Unknown EC flash region name '%s'\n", name);
1262 			return -1;
1263 		}
1264 
1265 		if (fdtdec_read_fmap_entry(blob, node, "reg",
1266 					   &config->region[region])) {
1267 			debug("Failed to decode flash region in chrome-ec'\n");
1268 			return -1;
1269 		}
1270 	}
1271 
1272 	return 0;
1273 }
1274 
1275 int cros_ec_i2c_xfer(struct cros_ec_dev *dev, uchar chip, uint addr,
1276 		     int alen, uchar *buffer, int len, int is_read)
1277 {
1278 	union {
1279 		struct ec_params_i2c_passthru p;
1280 		uint8_t outbuf[EC_PROTO2_MAX_PARAM_SIZE];
1281 	} params;
1282 	union {
1283 		struct ec_response_i2c_passthru r;
1284 		uint8_t inbuf[EC_PROTO2_MAX_PARAM_SIZE];
1285 	} response;
1286 	struct ec_params_i2c_passthru *p = &params.p;
1287 	struct ec_response_i2c_passthru *r = &response.r;
1288 	struct ec_params_i2c_passthru_msg *msg = p->msg;
1289 	uint8_t *pdata;
1290 	int read_len, write_len;
1291 	int size;
1292 	int rv;
1293 
1294 	p->port = 0;
1295 
1296 	if (alen != 1) {
1297 		printf("Unsupported address length %d\n", alen);
1298 		return -1;
1299 	}
1300 	if (is_read) {
1301 		read_len = len;
1302 		write_len = alen;
1303 		p->num_msgs = 2;
1304 	} else {
1305 		read_len = 0;
1306 		write_len = alen + len;
1307 		p->num_msgs = 1;
1308 	}
1309 
1310 	size = sizeof(*p) + p->num_msgs * sizeof(*msg);
1311 	if (size + write_len > sizeof(params)) {
1312 		puts("Params too large for buffer\n");
1313 		return -1;
1314 	}
1315 	if (sizeof(*r) + read_len > sizeof(response)) {
1316 		puts("Read length too big for buffer\n");
1317 		return -1;
1318 	}
1319 
1320 	/* Create a message to write the register address and optional data */
1321 	pdata = (uint8_t *)p + size;
1322 	msg->addr_flags = chip;
1323 	msg->len = write_len;
1324 	pdata[0] = addr;
1325 	if (!is_read)
1326 		memcpy(pdata + 1, buffer, len);
1327 	msg++;
1328 
1329 	if (read_len) {
1330 		msg->addr_flags = chip | EC_I2C_FLAG_READ;
1331 		msg->len = read_len;
1332 	}
1333 
1334 	rv = ec_command(dev, EC_CMD_I2C_PASSTHRU, 0, p, size + write_len,
1335 			r, sizeof(*r) + read_len);
1336 	if (rv < 0)
1337 		return rv;
1338 
1339 	/* Parse response */
1340 	if (r->i2c_status & EC_I2C_STATUS_ERROR) {
1341 		printf("Transfer failed with status=0x%x\n", r->i2c_status);
1342 		return -1;
1343 	}
1344 
1345 	if (rv < sizeof(*r) + read_len) {
1346 		puts("Truncated read response\n");
1347 		return -1;
1348 	}
1349 
1350 	if (read_len)
1351 		memcpy(buffer, r->data, read_len);
1352 
1353 	return 0;
1354 }
1355 
1356 #ifdef CONFIG_CMD_CROS_EC
1357 
1358 /**
1359  * Perform a flash read or write command
1360  *
1361  * @param dev		CROS-EC device to read/write
1362  * @param is_write	1 do to a write, 0 to do a read
1363  * @param argc		Number of arguments
1364  * @param argv		Arguments (2 is region, 3 is address)
1365  * @return 0 for ok, 1 for a usage error or -ve for ec command error
1366  *	(negative EC_RES_...)
1367  */
1368 static int do_read_write(struct cros_ec_dev *dev, int is_write, int argc,
1369 			 char * const argv[])
1370 {
1371 	uint32_t offset, size = -1U, region_size;
1372 	unsigned long addr;
1373 	char *endp;
1374 	int region;
1375 	int ret;
1376 
1377 	region = cros_ec_decode_region(argc - 2, argv + 2);
1378 	if (region == -1)
1379 		return 1;
1380 	if (argc < 4)
1381 		return 1;
1382 	addr = simple_strtoul(argv[3], &endp, 16);
1383 	if (*argv[3] == 0 || *endp != 0)
1384 		return 1;
1385 	if (argc > 4) {
1386 		size = simple_strtoul(argv[4], &endp, 16);
1387 		if (*argv[4] == 0 || *endp != 0)
1388 			return 1;
1389 	}
1390 
1391 	ret = cros_ec_flash_offset(dev, region, &offset, &region_size);
1392 	if (ret) {
1393 		debug("%s: Could not read region info\n", __func__);
1394 		return ret;
1395 	}
1396 	if (size == -1U)
1397 		size = region_size;
1398 
1399 	ret = is_write ?
1400 		cros_ec_flash_write(dev, (uint8_t *)addr, offset, size) :
1401 		cros_ec_flash_read(dev, (uint8_t *)addr, offset, size);
1402 	if (ret) {
1403 		debug("%s: Could not %s region\n", __func__,
1404 		      is_write ? "write" : "read");
1405 		return ret;
1406 	}
1407 
1408 	return 0;
1409 }
1410 
1411 /**
1412  * get_alen() - Small parser helper function to get address length
1413  *
1414  * Returns the address length.
1415  */
1416 static uint get_alen(char *arg)
1417 {
1418 	int	j;
1419 	int	alen;
1420 
1421 	alen = 1;
1422 	for (j = 0; j < 8; j++) {
1423 		if (arg[j] == '.') {
1424 			alen = arg[j+1] - '0';
1425 			break;
1426 		} else if (arg[j] == '\0') {
1427 			break;
1428 		}
1429 	}
1430 	return alen;
1431 }
1432 
1433 #define DISP_LINE_LEN	16
1434 
1435 /*
1436  * TODO(sjg@chromium.org): This code copied almost verbatim from cmd_i2c.c
1437  * so we can remove it later.
1438  */
1439 static int cros_ec_i2c_md(struct cros_ec_dev *dev, int flag, int argc,
1440 			  char * const argv[])
1441 {
1442 	u_char	chip;
1443 	uint	addr, alen, length = 0x10;
1444 	int	j, nbytes, linebytes;
1445 
1446 	if (argc < 2)
1447 		return CMD_RET_USAGE;
1448 
1449 	if (1 || (flag & CMD_FLAG_REPEAT) == 0) {
1450 		/*
1451 		 * New command specified.
1452 		 */
1453 
1454 		/*
1455 		 * I2C chip address
1456 		 */
1457 		chip = simple_strtoul(argv[0], NULL, 16);
1458 
1459 		/*
1460 		 * I2C data address within the chip.  This can be 1 or
1461 		 * 2 bytes long.  Some day it might be 3 bytes long :-).
1462 		 */
1463 		addr = simple_strtoul(argv[1], NULL, 16);
1464 		alen = get_alen(argv[1]);
1465 		if (alen > 3)
1466 			return CMD_RET_USAGE;
1467 
1468 		/*
1469 		 * If another parameter, it is the length to display.
1470 		 * Length is the number of objects, not number of bytes.
1471 		 */
1472 		if (argc > 2)
1473 			length = simple_strtoul(argv[2], NULL, 16);
1474 	}
1475 
1476 	/*
1477 	 * Print the lines.
1478 	 *
1479 	 * We buffer all read data, so we can make sure data is read only
1480 	 * once.
1481 	 */
1482 	nbytes = length;
1483 	do {
1484 		unsigned char	linebuf[DISP_LINE_LEN];
1485 		unsigned char	*cp;
1486 
1487 		linebytes = (nbytes > DISP_LINE_LEN) ? DISP_LINE_LEN : nbytes;
1488 
1489 		if (cros_ec_i2c_xfer(dev, chip, addr, alen, linebuf, linebytes,
1490 				     1))
1491 			puts("Error reading the chip.\n");
1492 		else {
1493 			printf("%04x:", addr);
1494 			cp = linebuf;
1495 			for (j = 0; j < linebytes; j++) {
1496 				printf(" %02x", *cp++);
1497 				addr++;
1498 			}
1499 			puts("    ");
1500 			cp = linebuf;
1501 			for (j = 0; j < linebytes; j++) {
1502 				if ((*cp < 0x20) || (*cp > 0x7e))
1503 					puts(".");
1504 				else
1505 					printf("%c", *cp);
1506 				cp++;
1507 			}
1508 			putc('\n');
1509 		}
1510 		nbytes -= linebytes;
1511 	} while (nbytes > 0);
1512 
1513 	return 0;
1514 }
1515 
1516 static int cros_ec_i2c_mw(struct cros_ec_dev *dev, int flag, int argc,
1517 			  char * const argv[])
1518 {
1519 	uchar	chip;
1520 	ulong	addr;
1521 	uint	alen;
1522 	uchar	byte;
1523 	int	count;
1524 
1525 	if ((argc < 3) || (argc > 4))
1526 		return CMD_RET_USAGE;
1527 
1528 	/*
1529 	 * Chip is always specified.
1530 	 */
1531 	chip = simple_strtoul(argv[0], NULL, 16);
1532 
1533 	/*
1534 	 * Address is always specified.
1535 	 */
1536 	addr = simple_strtoul(argv[1], NULL, 16);
1537 	alen = get_alen(argv[1]);
1538 	if (alen > 3)
1539 		return CMD_RET_USAGE;
1540 
1541 	/*
1542 	 * Value to write is always specified.
1543 	 */
1544 	byte = simple_strtoul(argv[2], NULL, 16);
1545 
1546 	/*
1547 	 * Optional count
1548 	 */
1549 	if (argc == 4)
1550 		count = simple_strtoul(argv[3], NULL, 16);
1551 	else
1552 		count = 1;
1553 
1554 	while (count-- > 0) {
1555 		if (cros_ec_i2c_xfer(dev, chip, addr++, alen, &byte, 1, 0))
1556 			puts("Error writing the chip.\n");
1557 		/*
1558 		 * Wait for the write to complete.  The write can take
1559 		 * up to 10mSec (we allow a little more time).
1560 		 */
1561 /*
1562  * No write delay with FRAM devices.
1563  */
1564 #if !defined(CONFIG_SYS_I2C_FRAM)
1565 		udelay(11000);
1566 #endif
1567 	}
1568 
1569 	return 0;
1570 }
1571 
1572 /* Temporary code until we have driver model and can use the i2c command */
1573 static int cros_ec_i2c_passthrough(struct cros_ec_dev *dev, int flag,
1574 				   int argc, char * const argv[])
1575 {
1576 	const char *cmd;
1577 
1578 	if (argc < 1)
1579 		return CMD_RET_USAGE;
1580 	cmd = *argv++;
1581 	argc--;
1582 	if (0 == strcmp("md", cmd))
1583 		cros_ec_i2c_md(dev, flag, argc, argv);
1584 	else if (0 == strcmp("mw", cmd))
1585 		cros_ec_i2c_mw(dev, flag, argc, argv);
1586 	else
1587 		return CMD_RET_USAGE;
1588 
1589 	return 0;
1590 }
1591 
1592 static int do_cros_ec(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
1593 {
1594 	struct cros_ec_dev *dev;
1595 #ifdef CONFIG_DM_CROS_EC
1596 	struct udevice *udev;
1597 #endif
1598 	const char *cmd;
1599 	int ret = 0;
1600 
1601 	if (argc < 2)
1602 		return CMD_RET_USAGE;
1603 
1604 	cmd = argv[1];
1605 	if (0 == strcmp("init", cmd)) {
1606 #ifndef CONFIG_DM_CROS_EC
1607 		ret = cros_ec_init(gd->fdt_blob, &dev);
1608 		if (ret) {
1609 			printf("Could not init cros_ec device (err %d)\n", ret);
1610 			return 1;
1611 		}
1612 #endif
1613 		return 0;
1614 	}
1615 
1616 #ifdef CONFIG_DM_CROS_EC
1617 	ret = uclass_get_device(UCLASS_CROS_EC, 0, &udev);
1618 	if (ret) {
1619 		printf("Cannot get cros-ec device (err=%d)\n", ret);
1620 		return 1;
1621 	}
1622 	dev = udev->uclass_priv;
1623 #else
1624 	/* Just use the last allocated device; there should be only one */
1625 	if (!last_dev) {
1626 		printf("No CROS-EC device available\n");
1627 		return 1;
1628 	}
1629 	dev = last_dev;
1630 #endif
1631 	if (0 == strcmp("id", cmd)) {
1632 		char id[MSG_BYTES];
1633 
1634 		if (cros_ec_read_id(dev, id, sizeof(id))) {
1635 			debug("%s: Could not read KBC ID\n", __func__);
1636 			return 1;
1637 		}
1638 		printf("%s\n", id);
1639 	} else if (0 == strcmp("info", cmd)) {
1640 		struct ec_response_mkbp_info info;
1641 
1642 		if (cros_ec_info(dev, &info)) {
1643 			debug("%s: Could not read KBC info\n", __func__);
1644 			return 1;
1645 		}
1646 		printf("rows     = %u\n", info.rows);
1647 		printf("cols     = %u\n", info.cols);
1648 		printf("switches = %#x\n", info.switches);
1649 	} else if (0 == strcmp("curimage", cmd)) {
1650 		enum ec_current_image image;
1651 
1652 		if (cros_ec_read_current_image(dev, &image)) {
1653 			debug("%s: Could not read KBC image\n", __func__);
1654 			return 1;
1655 		}
1656 		printf("%d\n", image);
1657 	} else if (0 == strcmp("hash", cmd)) {
1658 		struct ec_response_vboot_hash hash;
1659 		int i;
1660 
1661 		if (cros_ec_read_hash(dev, &hash)) {
1662 			debug("%s: Could not read KBC hash\n", __func__);
1663 			return 1;
1664 		}
1665 
1666 		if (hash.hash_type == EC_VBOOT_HASH_TYPE_SHA256)
1667 			printf("type:    SHA-256\n");
1668 		else
1669 			printf("type:    %d\n", hash.hash_type);
1670 
1671 		printf("offset:  0x%08x\n", hash.offset);
1672 		printf("size:    0x%08x\n", hash.size);
1673 
1674 		printf("digest:  ");
1675 		for (i = 0; i < hash.digest_size; i++)
1676 			printf("%02x", hash.hash_digest[i]);
1677 		printf("\n");
1678 	} else if (0 == strcmp("reboot", cmd)) {
1679 		int region;
1680 		enum ec_reboot_cmd cmd;
1681 
1682 		if (argc >= 3 && !strcmp(argv[2], "cold"))
1683 			cmd = EC_REBOOT_COLD;
1684 		else {
1685 			region = cros_ec_decode_region(argc - 2, argv + 2);
1686 			if (region == EC_FLASH_REGION_RO)
1687 				cmd = EC_REBOOT_JUMP_RO;
1688 			else if (region == EC_FLASH_REGION_RW)
1689 				cmd = EC_REBOOT_JUMP_RW;
1690 			else
1691 				return CMD_RET_USAGE;
1692 		}
1693 
1694 		if (cros_ec_reboot(dev, cmd, 0)) {
1695 			debug("%s: Could not reboot KBC\n", __func__);
1696 			return 1;
1697 		}
1698 	} else if (0 == strcmp("events", cmd)) {
1699 		uint32_t events;
1700 
1701 		if (cros_ec_get_host_events(dev, &events)) {
1702 			debug("%s: Could not read host events\n", __func__);
1703 			return 1;
1704 		}
1705 		printf("0x%08x\n", events);
1706 	} else if (0 == strcmp("clrevents", cmd)) {
1707 		uint32_t events = 0x7fffffff;
1708 
1709 		if (argc >= 3)
1710 			events = simple_strtol(argv[2], NULL, 0);
1711 
1712 		if (cros_ec_clear_host_events(dev, events)) {
1713 			debug("%s: Could not clear host events\n", __func__);
1714 			return 1;
1715 		}
1716 	} else if (0 == strcmp("read", cmd)) {
1717 		ret = do_read_write(dev, 0, argc, argv);
1718 		if (ret > 0)
1719 			return CMD_RET_USAGE;
1720 	} else if (0 == strcmp("write", cmd)) {
1721 		ret = do_read_write(dev, 1, argc, argv);
1722 		if (ret > 0)
1723 			return CMD_RET_USAGE;
1724 	} else if (0 == strcmp("erase", cmd)) {
1725 		int region = cros_ec_decode_region(argc - 2, argv + 2);
1726 		uint32_t offset, size;
1727 
1728 		if (region == -1)
1729 			return CMD_RET_USAGE;
1730 		if (cros_ec_flash_offset(dev, region, &offset, &size)) {
1731 			debug("%s: Could not read region info\n", __func__);
1732 			ret = -1;
1733 		} else {
1734 			ret = cros_ec_flash_erase(dev, offset, size);
1735 			if (ret) {
1736 				debug("%s: Could not erase region\n",
1737 				      __func__);
1738 			}
1739 		}
1740 	} else if (0 == strcmp("regioninfo", cmd)) {
1741 		int region = cros_ec_decode_region(argc - 2, argv + 2);
1742 		uint32_t offset, size;
1743 
1744 		if (region == -1)
1745 			return CMD_RET_USAGE;
1746 		ret = cros_ec_flash_offset(dev, region, &offset, &size);
1747 		if (ret) {
1748 			debug("%s: Could not read region info\n", __func__);
1749 		} else {
1750 			printf("Region: %s\n", region == EC_FLASH_REGION_RO ?
1751 					"RO" : "RW");
1752 			printf("Offset: %x\n", offset);
1753 			printf("Size:   %x\n", size);
1754 		}
1755 	} else if (0 == strcmp("vbnvcontext", cmd)) {
1756 		uint8_t block[EC_VBNV_BLOCK_SIZE];
1757 		char buf[3];
1758 		int i, len;
1759 		unsigned long result;
1760 
1761 		if (argc <= 2) {
1762 			ret = cros_ec_read_vbnvcontext(dev, block);
1763 			if (!ret) {
1764 				printf("vbnv_block: ");
1765 				for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++)
1766 					printf("%02x", block[i]);
1767 				putc('\n');
1768 			}
1769 		} else {
1770 			/*
1771 			 * TODO(clchiou): Move this to a utility function as
1772 			 * cmd_spi might want to call it.
1773 			 */
1774 			memset(block, 0, EC_VBNV_BLOCK_SIZE);
1775 			len = strlen(argv[2]);
1776 			buf[2] = '\0';
1777 			for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++) {
1778 				if (i * 2 >= len)
1779 					break;
1780 				buf[0] = argv[2][i * 2];
1781 				if (i * 2 + 1 >= len)
1782 					buf[1] = '0';
1783 				else
1784 					buf[1] = argv[2][i * 2 + 1];
1785 				strict_strtoul(buf, 16, &result);
1786 				block[i] = result;
1787 			}
1788 			ret = cros_ec_write_vbnvcontext(dev, block);
1789 		}
1790 		if (ret) {
1791 			debug("%s: Could not %s VbNvContext\n", __func__,
1792 					argc <= 2 ?  "read" : "write");
1793 		}
1794 	} else if (0 == strcmp("test", cmd)) {
1795 		int result = cros_ec_test(dev);
1796 
1797 		if (result)
1798 			printf("Test failed with error %d\n", result);
1799 		else
1800 			puts("Test passed\n");
1801 	} else if (0 == strcmp("version", cmd)) {
1802 		struct ec_response_get_version *p;
1803 		char *build_string;
1804 
1805 		ret = cros_ec_read_version(dev, &p);
1806 		if (!ret) {
1807 			/* Print versions */
1808 			printf("RO version:    %1.*s\n",
1809 			       (int)sizeof(p->version_string_ro),
1810 			       p->version_string_ro);
1811 			printf("RW version:    %1.*s\n",
1812 			       (int)sizeof(p->version_string_rw),
1813 			       p->version_string_rw);
1814 			printf("Firmware copy: %s\n",
1815 				(p->current_image <
1816 					ARRAY_SIZE(ec_current_image_name) ?
1817 				ec_current_image_name[p->current_image] :
1818 				"?"));
1819 			ret = cros_ec_read_build_info(dev, &build_string);
1820 			if (!ret)
1821 				printf("Build info:    %s\n", build_string);
1822 		}
1823 	} else if (0 == strcmp("ldo", cmd)) {
1824 		uint8_t index, state;
1825 		char *endp;
1826 
1827 		if (argc < 3)
1828 			return CMD_RET_USAGE;
1829 		index = simple_strtoul(argv[2], &endp, 10);
1830 		if (*argv[2] == 0 || *endp != 0)
1831 			return CMD_RET_USAGE;
1832 		if (argc > 3) {
1833 			state = simple_strtoul(argv[3], &endp, 10);
1834 			if (*argv[3] == 0 || *endp != 0)
1835 				return CMD_RET_USAGE;
1836 			ret = cros_ec_set_ldo(dev, index, state);
1837 		} else {
1838 			ret = cros_ec_get_ldo(dev, index, &state);
1839 			if (!ret) {
1840 				printf("LDO%d: %s\n", index,
1841 					state == EC_LDO_STATE_ON ?
1842 					"on" : "off");
1843 			}
1844 		}
1845 
1846 		if (ret) {
1847 			debug("%s: Could not access LDO%d\n", __func__, index);
1848 			return ret;
1849 		}
1850 	} else if (0 == strcmp("i2c", cmd)) {
1851 		ret = cros_ec_i2c_passthrough(dev, flag, argc - 2, argv + 2);
1852 	} else {
1853 		return CMD_RET_USAGE;
1854 	}
1855 
1856 	if (ret < 0) {
1857 		printf("Error: CROS-EC command failed (error %d)\n", ret);
1858 		ret = 1;
1859 	}
1860 
1861 	return ret;
1862 }
1863 
1864 U_BOOT_CMD(
1865 	crosec,	6,	1,	do_cros_ec,
1866 	"CROS-EC utility command",
1867 	"init                Re-init CROS-EC (done on startup automatically)\n"
1868 	"crosec id                  Read CROS-EC ID\n"
1869 	"crosec info                Read CROS-EC info\n"
1870 	"crosec curimage            Read CROS-EC current image\n"
1871 	"crosec hash                Read CROS-EC hash\n"
1872 	"crosec reboot [rw | ro | cold]  Reboot CROS-EC\n"
1873 	"crosec events              Read CROS-EC host events\n"
1874 	"crosec clrevents [mask]    Clear CROS-EC host events\n"
1875 	"crosec regioninfo <ro|rw>  Read image info\n"
1876 	"crosec erase <ro|rw>       Erase EC image\n"
1877 	"crosec read <ro|rw> <addr> [<size>]   Read EC image\n"
1878 	"crosec write <ro|rw> <addr> [<size>]  Write EC image\n"
1879 	"crosec vbnvcontext [hexstring]        Read [write] VbNvContext from EC\n"
1880 	"crosec ldo <idx> [<state>] Switch/Read LDO state\n"
1881 	"crosec test                run tests on cros_ec\n"
1882 	"crosec version             Read CROS-EC version\n"
1883 	"crosec i2c md chip address[.0, .1, .2] [# of objects] - read from I2C passthru\n"
1884 	"crosec i2c mw chip address[.0, .1, .2] value [count] - write to I2C passthru (fill)"
1885 );
1886 #endif
1887 
1888 #ifdef CONFIG_DM_CROS_EC
1889 UCLASS_DRIVER(cros_ec) = {
1890 	.id		= UCLASS_CROS_EC,
1891 	.name		= "cros_ec",
1892 	.per_device_auto_alloc_size = sizeof(struct cros_ec_dev),
1893 };
1894 #endif
1895