1 /*
2  *  linux/drivers/spi/spi-loopback-test.c
3  *
4  *  (c) Martin Sperl <kernel@martin.sperl.org>
5  *
6  *  Loopback test driver to test several typical spi_message conditions
7  *  that a spi_master driver may encounter
8  *  this can also get used for regression testing
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or
13  *  (at your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful,
16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *  GNU General Public License for more details.
19  */
20 
21 #include <linux/delay.h>
22 #include <linux/kernel.h>
23 #include <linux/ktime.h>
24 #include <linux/list.h>
25 #include <linux/list_sort.h>
26 #include <linux/module.h>
27 #include <linux/of_device.h>
28 #include <linux/printk.h>
29 #include <linux/vmalloc.h>
30 #include <linux/spi/spi.h>
31 
32 #include "spi-test.h"
33 
34 /* flag to only simulate transfers */
35 int simulate_only;
36 module_param(simulate_only, int, 0);
37 MODULE_PARM_DESC(simulate_only, "if not 0 do not execute the spi message");
38 
39 /* dump spi messages */
40 int dump_messages;
41 module_param(dump_messages, int, 0);
42 MODULE_PARM_DESC(dump_messages,
43 		 "=1 dump the basic spi_message_structure, " \
44 		 "=2 dump the spi_message_structure including data, " \
45 		 "=3 dump the spi_message structure before and after execution");
46 /* the device is jumpered for loopback - enabling some rx_buf tests */
47 int loopback;
48 module_param(loopback, int, 0);
49 MODULE_PARM_DESC(loopback,
50 		 "if set enable loopback mode, where the rx_buf "	\
51 		 "is checked to match tx_buf after the spi_message "	\
52 		 "is executed");
53 
54 /* run only a specific test */
55 int run_only_test = -1;
56 module_param(run_only_test, int, 0);
57 MODULE_PARM_DESC(run_only_test,
58 		 "only run the test with this number (0-based !)");
59 
60 /* use vmalloc'ed buffers */
61 int use_vmalloc;
62 module_param(use_vmalloc, int, 0644);
63 MODULE_PARM_DESC(use_vmalloc,
64 		 "use vmalloc'ed buffers instead of kmalloc'ed");
65 
66 /* check rx ranges */
67 int check_ranges = 1;
68 module_param(check_ranges, int, 0644);
69 MODULE_PARM_DESC(check_ranges,
70 		 "checks rx_buffer pattern are valid");
71 
72 /* the actual tests to execute */
73 static struct spi_test spi_tests[] = {
74 	{
75 		.description	= "tx/rx-transfer - start of page",
76 		.fill_option	= FILL_COUNT_8,
77 		.iterate_len    = { ITERATE_MAX_LEN },
78 		.iterate_tx_align = ITERATE_ALIGN,
79 		.iterate_rx_align = ITERATE_ALIGN,
80 		.transfer_count = 1,
81 		.transfers		= {
82 			{
83 				.tx_buf = TX(0),
84 				.rx_buf = RX(0),
85 			},
86 		},
87 	},
88 	{
89 		.description	= "tx/rx-transfer - crossing PAGE_SIZE",
90 		.fill_option	= FILL_COUNT_8,
91 		.iterate_len    = { ITERATE_MAX_LEN },
92 		.iterate_tx_align = ITERATE_ALIGN,
93 		.iterate_rx_align = ITERATE_ALIGN,
94 		.transfer_count = 1,
95 		.transfers		= {
96 			{
97 				.tx_buf = TX(PAGE_SIZE - 4),
98 				.rx_buf = RX(PAGE_SIZE - 4),
99 			},
100 		},
101 	},
102 	{
103 		.description	= "tx-transfer - only",
104 		.fill_option	= FILL_COUNT_8,
105 		.iterate_len    = { ITERATE_MAX_LEN },
106 		.iterate_tx_align = ITERATE_ALIGN,
107 		.transfer_count = 1,
108 		.transfers		= {
109 			{
110 				.tx_buf = TX(0),
111 			},
112 		},
113 	},
114 	{
115 		.description	= "rx-transfer - only",
116 		.fill_option	= FILL_COUNT_8,
117 		.iterate_len    = { ITERATE_MAX_LEN },
118 		.iterate_rx_align = ITERATE_ALIGN,
119 		.transfer_count = 1,
120 		.transfers		= {
121 			{
122 				.rx_buf = RX(0),
123 			},
124 		},
125 	},
126 	{
127 		.description	= "two tx-transfers - alter both",
128 		.fill_option	= FILL_COUNT_8,
129 		.iterate_len    = { ITERATE_LEN },
130 		.iterate_tx_align = ITERATE_ALIGN,
131 		.iterate_transfer_mask = BIT(0) | BIT(1),
132 		.transfer_count = 2,
133 		.transfers		= {
134 			{
135 				.tx_buf = TX(0),
136 			},
137 			{
138 				/* this is why we cant use ITERATE_MAX_LEN */
139 				.tx_buf = TX(SPI_TEST_MAX_SIZE_HALF),
140 			},
141 		},
142 	},
143 	{
144 		.description	= "two tx-transfers - alter first",
145 		.fill_option	= FILL_COUNT_8,
146 		.iterate_len    = { ITERATE_MAX_LEN },
147 		.iterate_tx_align = ITERATE_ALIGN,
148 		.iterate_transfer_mask = BIT(0),
149 		.transfer_count = 2,
150 		.transfers		= {
151 			{
152 				.tx_buf = TX(64),
153 			},
154 			{
155 				.len = 1,
156 				.tx_buf = TX(0),
157 			},
158 		},
159 	},
160 	{
161 		.description	= "two tx-transfers - alter second",
162 		.fill_option	= FILL_COUNT_8,
163 		.iterate_len    = { ITERATE_MAX_LEN },
164 		.iterate_tx_align = ITERATE_ALIGN,
165 		.iterate_transfer_mask = BIT(1),
166 		.transfer_count = 2,
167 		.transfers		= {
168 			{
169 				.len = 16,
170 				.tx_buf = TX(0),
171 			},
172 			{
173 				.tx_buf = TX(64),
174 			},
175 		},
176 	},
177 	{
178 		.description	= "two transfers tx then rx - alter both",
179 		.fill_option	= FILL_COUNT_8,
180 		.iterate_len    = { ITERATE_MAX_LEN },
181 		.iterate_tx_align = ITERATE_ALIGN,
182 		.iterate_transfer_mask = BIT(0) | BIT(1),
183 		.transfer_count = 2,
184 		.transfers		= {
185 			{
186 				.tx_buf = TX(0),
187 			},
188 			{
189 				.rx_buf = RX(0),
190 			},
191 		},
192 	},
193 	{
194 		.description	= "two transfers tx then rx - alter tx",
195 		.fill_option	= FILL_COUNT_8,
196 		.iterate_len    = { ITERATE_MAX_LEN },
197 		.iterate_tx_align = ITERATE_ALIGN,
198 		.iterate_transfer_mask = BIT(0),
199 		.transfer_count = 2,
200 		.transfers		= {
201 			{
202 				.tx_buf = TX(0),
203 			},
204 			{
205 				.len = 1,
206 				.rx_buf = RX(0),
207 			},
208 		},
209 	},
210 	{
211 		.description	= "two transfers tx then rx - alter rx",
212 		.fill_option	= FILL_COUNT_8,
213 		.iterate_len    = { ITERATE_MAX_LEN },
214 		.iterate_tx_align = ITERATE_ALIGN,
215 		.iterate_transfer_mask = BIT(1),
216 		.transfer_count = 2,
217 		.transfers		= {
218 			{
219 				.len = 1,
220 				.tx_buf = TX(0),
221 			},
222 			{
223 				.rx_buf = RX(0),
224 			},
225 		},
226 	},
227 	{
228 		.description	= "two tx+rx transfers - alter both",
229 		.fill_option	= FILL_COUNT_8,
230 		.iterate_len    = { ITERATE_LEN },
231 		.iterate_tx_align = ITERATE_ALIGN,
232 		.iterate_transfer_mask = BIT(0) | BIT(1),
233 		.transfer_count = 2,
234 		.transfers		= {
235 			{
236 				.tx_buf = TX(0),
237 				.rx_buf = RX(0),
238 			},
239 			{
240 				/* making sure we align without overwrite
241 				 * the reason we can not use ITERATE_MAX_LEN
242 				 */
243 				.tx_buf = TX(SPI_TEST_MAX_SIZE_HALF),
244 				.rx_buf = RX(SPI_TEST_MAX_SIZE_HALF),
245 			},
246 		},
247 	},
248 	{
249 		.description	= "two tx+rx transfers - alter first",
250 		.fill_option	= FILL_COUNT_8,
251 		.iterate_len    = { ITERATE_MAX_LEN },
252 		.iterate_tx_align = ITERATE_ALIGN,
253 		.iterate_transfer_mask = BIT(0),
254 		.transfer_count = 2,
255 		.transfers		= {
256 			{
257 				/* making sure we align without overwrite */
258 				.tx_buf = TX(1024),
259 				.rx_buf = RX(1024),
260 			},
261 			{
262 				.len = 1,
263 				/* making sure we align without overwrite */
264 				.tx_buf = TX(0),
265 				.rx_buf = RX(0),
266 			},
267 		},
268 	},
269 	{
270 		.description	= "two tx+rx transfers - alter second",
271 		.fill_option	= FILL_COUNT_8,
272 		.iterate_len    = { ITERATE_MAX_LEN },
273 		.iterate_tx_align = ITERATE_ALIGN,
274 		.iterate_transfer_mask = BIT(1),
275 		.transfer_count = 2,
276 		.transfers		= {
277 			{
278 				.len = 1,
279 				.tx_buf = TX(0),
280 				.rx_buf = RX(0),
281 			},
282 			{
283 				/* making sure we align without overwrite */
284 				.tx_buf = TX(1024),
285 				.rx_buf = RX(1024),
286 			},
287 		},
288 	},
289 	{
290 		.description	= "two tx+rx transfers - delay after transfer",
291 		.fill_option	= FILL_COUNT_8,
292 		.iterate_len    = { ITERATE_MAX_LEN },
293 		.iterate_transfer_mask = BIT(0) | BIT(1),
294 		.transfer_count = 2,
295 		.transfers		= {
296 			{
297 				.tx_buf = TX(0),
298 				.rx_buf = RX(0),
299 				.delay_usecs = 1000,
300 			},
301 			{
302 				.tx_buf = TX(0),
303 				.rx_buf = RX(0),
304 				.delay_usecs = 1000,
305 			},
306 		},
307 	},
308 
309 	{ /* end of tests sequence */ }
310 };
311 
312 static int spi_loopback_test_probe(struct spi_device *spi)
313 {
314 	int ret;
315 
316 	dev_info(&spi->dev, "Executing spi-loopback-tests\n");
317 
318 	ret = spi_test_run_tests(spi, spi_tests);
319 
320 	dev_info(&spi->dev, "Finished spi-loopback-tests with return: %i\n",
321 		 ret);
322 
323 	return ret;
324 }
325 
326 /* non const match table to permit to change via a module parameter */
327 static struct of_device_id spi_loopback_test_of_match[] = {
328 	{ .compatible	= "linux,spi-loopback-test", },
329 	{ }
330 };
331 
332 /* allow to override the compatible string via a module_parameter */
333 module_param_string(compatible, spi_loopback_test_of_match[0].compatible,
334 		    sizeof(spi_loopback_test_of_match[0].compatible),
335 		    0000);
336 
337 MODULE_DEVICE_TABLE(of, spi_loopback_test_of_match);
338 
339 static struct spi_driver spi_loopback_test_driver = {
340 	.driver = {
341 		.name = "spi-loopback-test",
342 		.owner = THIS_MODULE,
343 		.of_match_table = spi_loopback_test_of_match,
344 	},
345 	.probe = spi_loopback_test_probe,
346 };
347 
348 module_spi_driver(spi_loopback_test_driver);
349 
350 MODULE_AUTHOR("Martin Sperl <kernel@martin.sperl.org>");
351 MODULE_DESCRIPTION("test spi_driver to check core functionality");
352 MODULE_LICENSE("GPL");
353 
354 /*-------------------------------------------------------------------------*/
355 
356 /* spi_test implementation */
357 
358 #define RANGE_CHECK(ptr, plen, start, slen) \
359 	((ptr >= start) && (ptr + plen <= start + slen))
360 
361 /* we allocate one page more, to allow for offsets */
362 #define SPI_TEST_MAX_SIZE_PLUS (SPI_TEST_MAX_SIZE + PAGE_SIZE)
363 
364 static void spi_test_print_hex_dump(char *pre, const void *ptr, size_t len)
365 {
366 	/* limit the hex_dump */
367 	if (len < 1024) {
368 		print_hex_dump(KERN_INFO, pre,
369 			       DUMP_PREFIX_OFFSET, 16, 1,
370 			       ptr, len, 0);
371 		return;
372 	}
373 	/* print head */
374 	print_hex_dump(KERN_INFO, pre,
375 		       DUMP_PREFIX_OFFSET, 16, 1,
376 		       ptr, 512, 0);
377 	/* print tail */
378 	pr_info("%s truncated - continuing at offset %04zx\n",
379 		pre, len - 512);
380 	print_hex_dump(KERN_INFO, pre,
381 		       DUMP_PREFIX_OFFSET, 16, 1,
382 		       ptr + (len - 512), 512, 0);
383 }
384 
385 static void spi_test_dump_message(struct spi_device *spi,
386 				  struct spi_message *msg,
387 				  bool dump_data)
388 {
389 	struct spi_transfer *xfer;
390 	int i;
391 	u8 b;
392 
393 	dev_info(&spi->dev, "  spi_msg@%pK\n", msg);
394 	if (msg->status)
395 		dev_info(&spi->dev, "    status:        %i\n",
396 			 msg->status);
397 	dev_info(&spi->dev, "    frame_length:  %i\n",
398 		 msg->frame_length);
399 	dev_info(&spi->dev, "    actual_length: %i\n",
400 		 msg->actual_length);
401 
402 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
403 		dev_info(&spi->dev, "    spi_transfer@%pK\n", xfer);
404 		dev_info(&spi->dev, "      len:    %i\n", xfer->len);
405 		dev_info(&spi->dev, "      tx_buf: %pK\n", xfer->tx_buf);
406 		if (dump_data && xfer->tx_buf)
407 			spi_test_print_hex_dump("          TX: ",
408 						xfer->tx_buf,
409 						xfer->len);
410 
411 		dev_info(&spi->dev, "      rx_buf: %pK\n", xfer->rx_buf);
412 		if (dump_data && xfer->rx_buf)
413 			spi_test_print_hex_dump("          RX: ",
414 						xfer->rx_buf,
415 						xfer->len);
416 		/* check for unwritten test pattern on rx_buf */
417 		if (xfer->rx_buf) {
418 			for (i = 0 ; i < xfer->len ; i++) {
419 				b = ((u8 *)xfer->rx_buf)[xfer->len - 1 - i];
420 				if (b != SPI_TEST_PATTERN_UNWRITTEN)
421 					break;
422 			}
423 			if (i)
424 				dev_info(&spi->dev,
425 					 "      rx_buf filled with %02x starts at offset: %i\n",
426 					 SPI_TEST_PATTERN_UNWRITTEN,
427 					 xfer->len - i);
428 		}
429 	}
430 }
431 
432 struct rx_ranges {
433 	struct list_head list;
434 	u8 *start;
435 	u8 *end;
436 };
437 
438 static int rx_ranges_cmp(void *priv, struct list_head *a, struct list_head *b)
439 {
440 	struct rx_ranges *rx_a = list_entry(a, struct rx_ranges, list);
441 	struct rx_ranges *rx_b = list_entry(b, struct rx_ranges, list);
442 
443 	if (rx_a->start > rx_b->start)
444 		return 1;
445 	if (rx_a->start < rx_b->start)
446 		return -1;
447 	return 0;
448 }
449 
450 static int spi_check_rx_ranges(struct spi_device *spi,
451 			       struct spi_message *msg,
452 			       void *rx)
453 {
454 	struct spi_transfer *xfer;
455 	struct rx_ranges ranges[SPI_TEST_MAX_TRANSFERS], *r;
456 	int i = 0;
457 	LIST_HEAD(ranges_list);
458 	u8 *addr;
459 	int ret = 0;
460 
461 	/* loop over all transfers to fill in the rx_ranges */
462 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
463 		/* if there is no rx, then no check is needed */
464 		if (!xfer->rx_buf)
465 			continue;
466 		/* fill in the rx_range */
467 		if (RANGE_CHECK(xfer->rx_buf, xfer->len,
468 				rx, SPI_TEST_MAX_SIZE_PLUS)) {
469 			ranges[i].start = xfer->rx_buf;
470 			ranges[i].end = xfer->rx_buf + xfer->len;
471 			list_add(&ranges[i].list, &ranges_list);
472 			i++;
473 		}
474 	}
475 
476 	/* if no ranges, then we can return and avoid the checks...*/
477 	if (!i)
478 		return 0;
479 
480 	/* sort the list */
481 	list_sort(NULL, &ranges_list, rx_ranges_cmp);
482 
483 	/* and iterate over all the rx addresses */
484 	for (addr = rx; addr < (u8 *)rx + SPI_TEST_MAX_SIZE_PLUS; addr++) {
485 		/* if we are the DO not write pattern,
486 		 * then continue with the loop...
487 		 */
488 		if (*addr == SPI_TEST_PATTERN_DO_NOT_WRITE)
489 			continue;
490 
491 		/* check if we are inside a range */
492 		list_for_each_entry(r, &ranges_list, list) {
493 			/* if so then set to end... */
494 			if ((addr >= r->start) && (addr < r->end))
495 				addr = r->end;
496 		}
497 		/* second test after a (hopefull) translation */
498 		if (*addr == SPI_TEST_PATTERN_DO_NOT_WRITE)
499 			continue;
500 
501 		/* if still not found then something has modified too much */
502 		/* we could list the "closest" transfer here... */
503 		dev_err(&spi->dev,
504 			"loopback strangeness - rx changed outside of allowed range at: %pK\n",
505 			addr);
506 		/* do not return, only set ret,
507 		 * so that we list all addresses
508 		 */
509 		ret = -ERANGE;
510 	}
511 
512 	return ret;
513 }
514 
515 static int spi_test_check_elapsed_time(struct spi_device *spi,
516 				       struct spi_test *test)
517 {
518 	int i;
519 	unsigned long long estimated_time = 0;
520 	unsigned long long delay_usecs = 0;
521 
522 	for (i = 0; i < test->transfer_count; i++) {
523 		struct spi_transfer *xfer = test->transfers + i;
524 		unsigned long long nbits = (unsigned long long)BITS_PER_BYTE *
525 					   xfer->len;
526 
527 		delay_usecs += xfer->delay_usecs;
528 		if (!xfer->speed_hz)
529 			continue;
530 		estimated_time += div_u64(nbits * NSEC_PER_SEC, xfer->speed_hz);
531 	}
532 
533 	estimated_time += delay_usecs * NSEC_PER_USEC;
534 	if (test->elapsed_time < estimated_time) {
535 		dev_err(&spi->dev,
536 			"elapsed time %lld ns is shorter than minimum estimated time %lld ns\n",
537 			test->elapsed_time, estimated_time);
538 
539 		return -EINVAL;
540 	}
541 
542 	return 0;
543 }
544 
545 static int spi_test_check_loopback_result(struct spi_device *spi,
546 					  struct spi_message *msg,
547 					  void *tx, void *rx)
548 {
549 	struct spi_transfer *xfer;
550 	u8 rxb, txb;
551 	size_t i;
552 	int ret;
553 
554 	/* checks rx_buffer pattern are valid with loopback or without */
555 	if (check_ranges) {
556 		ret = spi_check_rx_ranges(spi, msg, rx);
557 		if (ret)
558 			return ret;
559 	}
560 
561 	/* if we run without loopback, then return now */
562 	if (!loopback)
563 		return 0;
564 
565 	/* if applicable to transfer check that rx_buf is equal to tx_buf */
566 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
567 		/* if there is no rx, then no check is needed */
568 		if (!xfer->len || !xfer->rx_buf)
569 			continue;
570 		/* so depending on tx_buf we need to handle things */
571 		if (xfer->tx_buf) {
572 			for (i = 0; i < xfer->len; i++) {
573 				txb = ((u8 *)xfer->tx_buf)[i];
574 				rxb = ((u8 *)xfer->rx_buf)[i];
575 				if (txb != rxb)
576 					goto mismatch_error;
577 			}
578 		} else {
579 			/* first byte received */
580 			txb = ((u8 *)xfer->rx_buf)[0];
581 			/* first byte may be 0 or xff */
582 			if (!((txb == 0) || (txb == 0xff))) {
583 				dev_err(&spi->dev,
584 					"loopback strangeness - we expect 0x00 or 0xff, but not 0x%02x\n",
585 					txb);
586 				return -EINVAL;
587 			}
588 			/* check that all bytes are identical */
589 			for (i = 1; i < xfer->len; i++) {
590 				rxb = ((u8 *)xfer->rx_buf)[i];
591 				if (rxb != txb)
592 					goto mismatch_error;
593 			}
594 		}
595 	}
596 
597 	return 0;
598 
599 mismatch_error:
600 	dev_err(&spi->dev,
601 		"loopback strangeness - transfer mismatch on byte %04zx - expected 0x%02x, but got 0x%02x\n",
602 		i, txb, rxb);
603 
604 	return -EINVAL;
605 }
606 
607 static int spi_test_translate(struct spi_device *spi,
608 			      void **ptr, size_t len,
609 			      void *tx, void *rx)
610 {
611 	size_t off;
612 
613 	/* return on null */
614 	if (!*ptr)
615 		return 0;
616 
617 	/* in the MAX_SIZE_HALF case modify the pointer */
618 	if (((size_t)*ptr) & SPI_TEST_MAX_SIZE_HALF)
619 		/* move the pointer to the correct range */
620 		*ptr += (SPI_TEST_MAX_SIZE_PLUS / 2) -
621 			SPI_TEST_MAX_SIZE_HALF;
622 
623 	/* RX range
624 	 * - we check against MAX_SIZE_PLUS to allow for automated alignment
625 	 */
626 	if (RANGE_CHECK(*ptr, len,  RX(0), SPI_TEST_MAX_SIZE_PLUS)) {
627 		off = *ptr - RX(0);
628 		*ptr = rx + off;
629 
630 		return 0;
631 	}
632 
633 	/* TX range */
634 	if (RANGE_CHECK(*ptr, len,  TX(0), SPI_TEST_MAX_SIZE_PLUS)) {
635 		off = *ptr - TX(0);
636 		*ptr = tx + off;
637 
638 		return 0;
639 	}
640 
641 	dev_err(&spi->dev,
642 		"PointerRange [%pK:%pK[ not in range [%pK:%pK[ or [%pK:%pK[\n",
643 		*ptr, *ptr + len,
644 		RX(0), RX(SPI_TEST_MAX_SIZE),
645 		TX(0), TX(SPI_TEST_MAX_SIZE));
646 
647 	return -EINVAL;
648 }
649 
650 static int spi_test_fill_pattern(struct spi_device *spi,
651 				 struct spi_test *test)
652 {
653 	struct spi_transfer *xfers = test->transfers;
654 	u8 *tx_buf;
655 	size_t count = 0;
656 	int i, j;
657 
658 #ifdef __BIG_ENDIAN
659 #define GET_VALUE_BYTE(value, index, bytes) \
660 	(value >> (8 * (bytes - 1 - count % bytes)))
661 #else
662 #define GET_VALUE_BYTE(value, index, bytes) \
663 	(value >> (8 * (count % bytes)))
664 #endif
665 
666 	/* fill all transfers with the pattern requested */
667 	for (i = 0; i < test->transfer_count; i++) {
668 		/* fill rx_buf with SPI_TEST_PATTERN_UNWRITTEN */
669 		if (xfers[i].rx_buf)
670 			memset(xfers[i].rx_buf, SPI_TEST_PATTERN_UNWRITTEN,
671 			       xfers[i].len);
672 		/* if tx_buf is NULL then skip */
673 		tx_buf = (u8 *)xfers[i].tx_buf;
674 		if (!tx_buf)
675 			continue;
676 		/* modify all the transfers */
677 		for (j = 0; j < xfers[i].len; j++, tx_buf++, count++) {
678 			/* fill tx */
679 			switch (test->fill_option) {
680 			case FILL_MEMSET_8:
681 				*tx_buf = test->fill_pattern;
682 				break;
683 			case FILL_MEMSET_16:
684 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
685 							 count, 2);
686 				break;
687 			case FILL_MEMSET_24:
688 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
689 							 count, 3);
690 				break;
691 			case FILL_MEMSET_32:
692 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
693 							 count, 4);
694 				break;
695 			case FILL_COUNT_8:
696 				*tx_buf = count;
697 				break;
698 			case FILL_COUNT_16:
699 				*tx_buf = GET_VALUE_BYTE(count, count, 2);
700 				break;
701 			case FILL_COUNT_24:
702 				*tx_buf = GET_VALUE_BYTE(count, count, 3);
703 				break;
704 			case FILL_COUNT_32:
705 				*tx_buf = GET_VALUE_BYTE(count, count, 4);
706 				break;
707 			case FILL_TRANSFER_BYTE_8:
708 				*tx_buf = j;
709 				break;
710 			case FILL_TRANSFER_BYTE_16:
711 				*tx_buf = GET_VALUE_BYTE(j, j, 2);
712 				break;
713 			case FILL_TRANSFER_BYTE_24:
714 				*tx_buf = GET_VALUE_BYTE(j, j, 3);
715 				break;
716 			case FILL_TRANSFER_BYTE_32:
717 				*tx_buf = GET_VALUE_BYTE(j, j, 4);
718 				break;
719 			case FILL_TRANSFER_NUM:
720 				*tx_buf = i;
721 				break;
722 			default:
723 				dev_err(&spi->dev,
724 					"unsupported fill_option: %i\n",
725 					test->fill_option);
726 				return -EINVAL;
727 			}
728 		}
729 	}
730 
731 	return 0;
732 }
733 
734 static int _spi_test_run_iter(struct spi_device *spi,
735 			      struct spi_test *test,
736 			      void *tx, void *rx)
737 {
738 	struct spi_message *msg = &test->msg;
739 	struct spi_transfer *x;
740 	int i, ret;
741 
742 	/* initialize message - zero-filled via static initialization */
743 	spi_message_init_no_memset(msg);
744 
745 	/* fill rx with the DO_NOT_WRITE pattern */
746 	memset(rx, SPI_TEST_PATTERN_DO_NOT_WRITE, SPI_TEST_MAX_SIZE_PLUS);
747 
748 	/* add the individual transfers */
749 	for (i = 0; i < test->transfer_count; i++) {
750 		x = &test->transfers[i];
751 
752 		/* patch the values of tx_buf */
753 		ret = spi_test_translate(spi, (void **)&x->tx_buf, x->len,
754 					 (void *)tx, rx);
755 		if (ret)
756 			return ret;
757 
758 		/* patch the values of rx_buf */
759 		ret = spi_test_translate(spi, &x->rx_buf, x->len,
760 					 (void *)tx, rx);
761 		if (ret)
762 			return ret;
763 
764 		/* and add it to the list */
765 		spi_message_add_tail(x, msg);
766 	}
767 
768 	/* fill in the transfer buffers with pattern */
769 	ret = spi_test_fill_pattern(spi, test);
770 	if (ret)
771 		return ret;
772 
773 	/* and execute */
774 	if (test->execute_msg)
775 		ret = test->execute_msg(spi, test, tx, rx);
776 	else
777 		ret = spi_test_execute_msg(spi, test, tx, rx);
778 
779 	/* handle result */
780 	if (ret == test->expected_return)
781 		return 0;
782 
783 	dev_err(&spi->dev,
784 		"test failed - test returned %i, but we expect %i\n",
785 		ret, test->expected_return);
786 
787 	if (ret)
788 		return ret;
789 
790 	/* if it is 0, as we expected something else,
791 	 * then return something special
792 	 */
793 	return -EFAULT;
794 }
795 
796 static int spi_test_run_iter(struct spi_device *spi,
797 			     const struct spi_test *testtemplate,
798 			     void *tx, void *rx,
799 			     size_t len,
800 			     size_t tx_off,
801 			     size_t rx_off
802 	)
803 {
804 	struct spi_test test;
805 	int i, tx_count, rx_count;
806 
807 	/* copy the test template to test */
808 	memcpy(&test, testtemplate, sizeof(test));
809 
810 	/* if iterate_transfer_mask is not set,
811 	 * then set it to first transfer only
812 	 */
813 	if (!(test.iterate_transfer_mask & (BIT(test.transfer_count) - 1)))
814 		test.iterate_transfer_mask = 1;
815 
816 	/* count number of transfers with tx/rx_buf != NULL */
817 	rx_count = tx_count = 0;
818 	for (i = 0; i < test.transfer_count; i++) {
819 		if (test.transfers[i].tx_buf)
820 			tx_count++;
821 		if (test.transfers[i].rx_buf)
822 			rx_count++;
823 	}
824 
825 	/* in some iteration cases warn and exit early,
826 	 * as there is nothing to do, that has not been tested already...
827 	 */
828 	if (tx_off && (!tx_count)) {
829 		dev_warn_once(&spi->dev,
830 			      "%s: iterate_tx_off configured with tx_buf==NULL - ignoring\n",
831 			      test.description);
832 		return 0;
833 	}
834 	if (rx_off && (!rx_count)) {
835 		dev_warn_once(&spi->dev,
836 			      "%s: iterate_rx_off configured with rx_buf==NULL - ignoring\n",
837 			      test.description);
838 		return 0;
839 	}
840 
841 	/* write out info */
842 	if (!(len || tx_off || rx_off)) {
843 		dev_info(&spi->dev, "Running test %s\n", test.description);
844 	} else {
845 		dev_info(&spi->dev,
846 			 "  with iteration values: len = %zu, tx_off = %zu, rx_off = %zu\n",
847 			 len, tx_off, rx_off);
848 	}
849 
850 	/* update in the values from iteration values */
851 	for (i = 0; i < test.transfer_count; i++) {
852 		/* only when bit in transfer mask is set */
853 		if (!(test.iterate_transfer_mask & BIT(i)))
854 			continue;
855 		test.transfers[i].len = len;
856 		if (test.transfers[i].tx_buf)
857 			test.transfers[i].tx_buf += tx_off;
858 		if (test.transfers[i].tx_buf)
859 			test.transfers[i].rx_buf += rx_off;
860 	}
861 
862 	/* and execute */
863 	return _spi_test_run_iter(spi, &test, tx, rx);
864 }
865 
866 /**
867  * spi_test_execute_msg - default implementation to run a test
868  *
869  * spi: @spi_device on which to run the @spi_message
870  * test: the test to execute, which already contains @msg
871  * tx:   the tx buffer allocated for the test sequence
872  * rx:   the rx buffer allocated for the test sequence
873  *
874  * Returns: error code of spi_sync as well as basic error checking
875  */
876 int spi_test_execute_msg(struct spi_device *spi, struct spi_test *test,
877 			 void *tx, void *rx)
878 {
879 	struct spi_message *msg = &test->msg;
880 	int ret = 0;
881 	int i;
882 
883 	/* only if we do not simulate */
884 	if (!simulate_only) {
885 		ktime_t start;
886 
887 		/* dump the complete message before and after the transfer */
888 		if (dump_messages == 3)
889 			spi_test_dump_message(spi, msg, true);
890 
891 		start = ktime_get();
892 		/* run spi message */
893 		ret = spi_sync(spi, msg);
894 		test->elapsed_time = ktime_to_ns(ktime_sub(ktime_get(), start));
895 		if (ret == -ETIMEDOUT) {
896 			dev_info(&spi->dev,
897 				 "spi-message timed out - reruning...\n");
898 			/* rerun after a few explicit schedules */
899 			for (i = 0; i < 16; i++)
900 				schedule();
901 			ret = spi_sync(spi, msg);
902 		}
903 		if (ret) {
904 			dev_err(&spi->dev,
905 				"Failed to execute spi_message: %i\n",
906 				ret);
907 			goto exit;
908 		}
909 
910 		/* do some extra error checks */
911 		if (msg->frame_length != msg->actual_length) {
912 			dev_err(&spi->dev,
913 				"actual length differs from expected\n");
914 			ret = -EIO;
915 			goto exit;
916 		}
917 
918 		/* run rx-buffer tests */
919 		ret = spi_test_check_loopback_result(spi, msg, tx, rx);
920 		if (ret)
921 			goto exit;
922 
923 		ret = spi_test_check_elapsed_time(spi, test);
924 	}
925 
926 	/* if requested or on error dump message (including data) */
927 exit:
928 	if (dump_messages || ret)
929 		spi_test_dump_message(spi, msg,
930 				      (dump_messages >= 2) || (ret));
931 
932 	return ret;
933 }
934 EXPORT_SYMBOL_GPL(spi_test_execute_msg);
935 
936 /**
937  * spi_test_run_test - run an individual spi_test
938  *                     including all the relevant iterations on:
939  *                     length and buffer alignment
940  *
941  * spi:  the spi_device to send the messages to
942  * test: the test which we need to execute
943  * tx:   the tx buffer allocated for the test sequence
944  * rx:   the rx buffer allocated for the test sequence
945  *
946  * Returns: status code of spi_sync or other failures
947  */
948 
949 int spi_test_run_test(struct spi_device *spi, const struct spi_test *test,
950 		      void *tx, void *rx)
951 {
952 	int idx_len;
953 	size_t len;
954 	size_t tx_align, rx_align;
955 	int ret;
956 
957 	/* test for transfer limits */
958 	if (test->transfer_count >= SPI_TEST_MAX_TRANSFERS) {
959 		dev_err(&spi->dev,
960 			"%s: Exceeded max number of transfers with %i\n",
961 			test->description, test->transfer_count);
962 		return -E2BIG;
963 	}
964 
965 	/* setting up some values in spi_message
966 	 * based on some settings in spi_master
967 	 * some of this can also get done in the run() method
968 	 */
969 
970 	/* iterate over all the iterable values using macros
971 	 * (to make it a bit more readable...
972 	 */
973 #define FOR_EACH_ALIGNMENT(var)						\
974 	for (var = 0;							\
975 	    var < (test->iterate_##var ?				\
976 			(spi->master->dma_alignment ?			\
977 			 spi->master->dma_alignment :			\
978 			 test->iterate_##var) :				\
979 			1);						\
980 	    var++)
981 
982 	for (idx_len = 0; idx_len < SPI_TEST_MAX_ITERATE &&
983 	     (len = test->iterate_len[idx_len]) != -1; idx_len++) {
984 		FOR_EACH_ALIGNMENT(tx_align) {
985 			FOR_EACH_ALIGNMENT(rx_align) {
986 				/* and run the iteration */
987 				ret = spi_test_run_iter(spi, test,
988 							tx, rx,
989 							len,
990 							tx_align,
991 							rx_align);
992 				if (ret)
993 					return ret;
994 			}
995 		}
996 	}
997 
998 	return 0;
999 }
1000 EXPORT_SYMBOL_GPL(spi_test_run_test);
1001 
1002 /**
1003  * spi_test_run_tests - run an array of spi_messages tests
1004  * @spi: the spi device on which to run the tests
1005  * @tests: NULL-terminated array of @spi_test
1006  *
1007  * Returns: status errors as per @spi_test_run_test()
1008  */
1009 
1010 int spi_test_run_tests(struct spi_device *spi,
1011 		       struct spi_test *tests)
1012 {
1013 	char *rx = NULL, *tx = NULL;
1014 	int ret = 0, count = 0;
1015 	struct spi_test *test;
1016 
1017 	/* allocate rx/tx buffers of 128kB size without devm
1018 	 * in the hope that is on a page boundary
1019 	 */
1020 	if (use_vmalloc)
1021 		rx = vmalloc(SPI_TEST_MAX_SIZE_PLUS);
1022 	else
1023 		rx = kzalloc(SPI_TEST_MAX_SIZE_PLUS, GFP_KERNEL);
1024 	if (!rx) {
1025 		ret = -ENOMEM;
1026 		goto out;
1027 	}
1028 
1029 	if (use_vmalloc)
1030 		tx = vmalloc(SPI_TEST_MAX_SIZE_PLUS);
1031 	else
1032 		tx = kzalloc(SPI_TEST_MAX_SIZE_PLUS, GFP_KERNEL);
1033 	if (!tx) {
1034 		ret = -ENOMEM;
1035 		goto out;
1036 	}
1037 
1038 	/* now run the individual tests in the table */
1039 	for (test = tests, count = 0; test->description[0];
1040 	     test++, count++) {
1041 		/* only run test if requested */
1042 		if ((run_only_test > -1) && (count != run_only_test))
1043 			continue;
1044 		/* run custom implementation */
1045 		if (test->run_test)
1046 			ret = test->run_test(spi, test, tx, rx);
1047 		else
1048 			ret = spi_test_run_test(spi, test, tx, rx);
1049 		if (ret)
1050 			goto out;
1051 		/* add some delays so that we can easily
1052 		 * detect the individual tests when using a logic analyzer
1053 		 * we also add scheduling to avoid potential spi_timeouts...
1054 		 */
1055 		mdelay(100);
1056 		schedule();
1057 	}
1058 
1059 out:
1060 	kvfree(rx);
1061 	kvfree(tx);
1062 	return ret;
1063 }
1064 EXPORT_SYMBOL_GPL(spi_test_run_tests);
1065