1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  linux/drivers/spi/spi-loopback-test.c
4  *
5  *  (c) Martin Sperl <kernel@martin.sperl.org>
6  *
7  *  Loopback test driver to test several typical spi_message conditions
8  *  that a spi_master driver may encounter
9  *  this can also get used for regression testing
10  */
11 
12 #include <linux/delay.h>
13 #include <linux/kernel.h>
14 #include <linux/ktime.h>
15 #include <linux/list.h>
16 #include <linux/list_sort.h>
17 #include <linux/module.h>
18 #include <linux/of_device.h>
19 #include <linux/printk.h>
20 #include <linux/vmalloc.h>
21 #include <linux/spi/spi.h>
22 
23 #include "spi-test.h"
24 
25 /* flag to only simulate transfers */
26 static int simulate_only;
27 module_param(simulate_only, int, 0);
28 MODULE_PARM_DESC(simulate_only, "if not 0 do not execute the spi message");
29 
30 /* dump spi messages */
31 static int dump_messages;
32 module_param(dump_messages, int, 0);
33 MODULE_PARM_DESC(dump_messages,
34 		 "=1 dump the basic spi_message_structure, " \
35 		 "=2 dump the spi_message_structure including data, " \
36 		 "=3 dump the spi_message structure before and after execution");
37 /* the device is jumpered for loopback - enabling some rx_buf tests */
38 static int loopback;
39 module_param(loopback, int, 0);
40 MODULE_PARM_DESC(loopback,
41 		 "if set enable loopback mode, where the rx_buf "	\
42 		 "is checked to match tx_buf after the spi_message "	\
43 		 "is executed");
44 
45 static int loop_req;
46 module_param(loop_req, int, 0);
47 MODULE_PARM_DESC(loop_req,
48 		 "if set controller will be asked to enable test loop mode. " \
49 		 "If controller supported it, MISO and MOSI will be connected");
50 
51 static int no_cs;
52 module_param(no_cs, int, 0);
53 MODULE_PARM_DESC(no_cs,
54 		 "if set Chip Select (CS) will not be used");
55 
56 /* run only a specific test */
57 static int run_only_test = -1;
58 module_param(run_only_test, int, 0);
59 MODULE_PARM_DESC(run_only_test,
60 		 "only run the test with this number (0-based !)");
61 
62 /* use vmalloc'ed buffers */
63 static int use_vmalloc;
64 module_param(use_vmalloc, int, 0644);
65 MODULE_PARM_DESC(use_vmalloc,
66 		 "use vmalloc'ed buffers instead of kmalloc'ed");
67 
68 /* check rx ranges */
69 static int check_ranges = 1;
70 module_param(check_ranges, int, 0644);
71 MODULE_PARM_DESC(check_ranges,
72 		 "checks rx_buffer pattern are valid");
73 
74 /* the actual tests to execute */
75 static struct spi_test spi_tests[] = {
76 	{
77 		.description	= "tx/rx-transfer - start of page",
78 		.fill_option	= FILL_COUNT_8,
79 		.iterate_len    = { ITERATE_MAX_LEN },
80 		.iterate_tx_align = ITERATE_ALIGN,
81 		.iterate_rx_align = ITERATE_ALIGN,
82 		.transfer_count = 1,
83 		.transfers		= {
84 			{
85 				.tx_buf = TX(0),
86 				.rx_buf = RX(0),
87 			},
88 		},
89 	},
90 	{
91 		.description	= "tx/rx-transfer - crossing PAGE_SIZE",
92 		.fill_option	= FILL_COUNT_8,
93 		.iterate_len    = { ITERATE_LEN },
94 		.iterate_tx_align = ITERATE_ALIGN,
95 		.iterate_rx_align = ITERATE_ALIGN,
96 		.transfer_count = 1,
97 		.transfers		= {
98 			{
99 				.tx_buf = TX(PAGE_SIZE - 4),
100 				.rx_buf = RX(PAGE_SIZE - 4),
101 			},
102 		},
103 	},
104 	{
105 		.description	= "tx-transfer - only",
106 		.fill_option	= FILL_COUNT_8,
107 		.iterate_len    = { ITERATE_MAX_LEN },
108 		.iterate_tx_align = ITERATE_ALIGN,
109 		.transfer_count = 1,
110 		.transfers		= {
111 			{
112 				.tx_buf = TX(0),
113 			},
114 		},
115 	},
116 	{
117 		.description	= "rx-transfer - only",
118 		.fill_option	= FILL_COUNT_8,
119 		.iterate_len    = { ITERATE_MAX_LEN },
120 		.iterate_rx_align = ITERATE_ALIGN,
121 		.transfer_count = 1,
122 		.transfers		= {
123 			{
124 				.rx_buf = RX(0),
125 			},
126 		},
127 	},
128 	{
129 		.description	= "two tx-transfers - alter both",
130 		.fill_option	= FILL_COUNT_8,
131 		.iterate_len    = { ITERATE_LEN },
132 		.iterate_tx_align = ITERATE_ALIGN,
133 		.iterate_transfer_mask = BIT(0) | BIT(1),
134 		.transfer_count = 2,
135 		.transfers		= {
136 			{
137 				.tx_buf = TX(0),
138 			},
139 			{
140 				/* this is why we cant use ITERATE_MAX_LEN */
141 				.tx_buf = TX(SPI_TEST_MAX_SIZE_HALF),
142 			},
143 		},
144 	},
145 	{
146 		.description	= "two tx-transfers - alter first",
147 		.fill_option	= FILL_COUNT_8,
148 		.iterate_len    = { ITERATE_MAX_LEN },
149 		.iterate_tx_align = ITERATE_ALIGN,
150 		.iterate_transfer_mask = BIT(0),
151 		.transfer_count = 2,
152 		.transfers		= {
153 			{
154 				.tx_buf = TX(64),
155 			},
156 			{
157 				.len = 1,
158 				.tx_buf = TX(0),
159 			},
160 		},
161 	},
162 	{
163 		.description	= "two tx-transfers - alter second",
164 		.fill_option	= FILL_COUNT_8,
165 		.iterate_len    = { ITERATE_MAX_LEN },
166 		.iterate_tx_align = ITERATE_ALIGN,
167 		.iterate_transfer_mask = BIT(1),
168 		.transfer_count = 2,
169 		.transfers		= {
170 			{
171 				.len = 16,
172 				.tx_buf = TX(0),
173 			},
174 			{
175 				.tx_buf = TX(64),
176 			},
177 		},
178 	},
179 	{
180 		.description	= "two transfers tx then rx - alter both",
181 		.fill_option	= FILL_COUNT_8,
182 		.iterate_len    = { ITERATE_MAX_LEN },
183 		.iterate_tx_align = ITERATE_ALIGN,
184 		.iterate_transfer_mask = BIT(0) | BIT(1),
185 		.transfer_count = 2,
186 		.transfers		= {
187 			{
188 				.tx_buf = TX(0),
189 			},
190 			{
191 				.rx_buf = RX(0),
192 			},
193 		},
194 	},
195 	{
196 		.description	= "two transfers tx then rx - alter tx",
197 		.fill_option	= FILL_COUNT_8,
198 		.iterate_len    = { ITERATE_MAX_LEN },
199 		.iterate_tx_align = ITERATE_ALIGN,
200 		.iterate_transfer_mask = BIT(0),
201 		.transfer_count = 2,
202 		.transfers		= {
203 			{
204 				.tx_buf = TX(0),
205 			},
206 			{
207 				.len = 1,
208 				.rx_buf = RX(0),
209 			},
210 		},
211 	},
212 	{
213 		.description	= "two transfers tx then rx - alter rx",
214 		.fill_option	= FILL_COUNT_8,
215 		.iterate_len    = { ITERATE_MAX_LEN },
216 		.iterate_tx_align = ITERATE_ALIGN,
217 		.iterate_transfer_mask = BIT(1),
218 		.transfer_count = 2,
219 		.transfers		= {
220 			{
221 				.len = 1,
222 				.tx_buf = TX(0),
223 			},
224 			{
225 				.rx_buf = RX(0),
226 			},
227 		},
228 	},
229 	{
230 		.description	= "two tx+rx transfers - alter both",
231 		.fill_option	= FILL_COUNT_8,
232 		.iterate_len    = { ITERATE_LEN },
233 		.iterate_tx_align = ITERATE_ALIGN,
234 		.iterate_transfer_mask = BIT(0) | BIT(1),
235 		.transfer_count = 2,
236 		.transfers		= {
237 			{
238 				.tx_buf = TX(0),
239 				.rx_buf = RX(0),
240 			},
241 			{
242 				/* making sure we align without overwrite
243 				 * the reason we can not use ITERATE_MAX_LEN
244 				 */
245 				.tx_buf = TX(SPI_TEST_MAX_SIZE_HALF),
246 				.rx_buf = RX(SPI_TEST_MAX_SIZE_HALF),
247 			},
248 		},
249 	},
250 	{
251 		.description	= "two tx+rx transfers - alter first",
252 		.fill_option	= FILL_COUNT_8,
253 		.iterate_len    = { ITERATE_MAX_LEN },
254 		.iterate_tx_align = ITERATE_ALIGN,
255 		.iterate_transfer_mask = BIT(0),
256 		.transfer_count = 2,
257 		.transfers		= {
258 			{
259 				/* making sure we align without overwrite */
260 				.tx_buf = TX(1024),
261 				.rx_buf = RX(1024),
262 			},
263 			{
264 				.len = 1,
265 				/* making sure we align without overwrite */
266 				.tx_buf = TX(0),
267 				.rx_buf = RX(0),
268 			},
269 		},
270 	},
271 	{
272 		.description	= "two tx+rx transfers - alter second",
273 		.fill_option	= FILL_COUNT_8,
274 		.iterate_len    = { ITERATE_MAX_LEN },
275 		.iterate_tx_align = ITERATE_ALIGN,
276 		.iterate_transfer_mask = BIT(1),
277 		.transfer_count = 2,
278 		.transfers		= {
279 			{
280 				.len = 1,
281 				.tx_buf = TX(0),
282 				.rx_buf = RX(0),
283 			},
284 			{
285 				/* making sure we align without overwrite */
286 				.tx_buf = TX(1024),
287 				.rx_buf = RX(1024),
288 			},
289 		},
290 	},
291 	{
292 		.description	= "two tx+rx transfers - delay after transfer",
293 		.fill_option	= FILL_COUNT_8,
294 		.iterate_len    = { ITERATE_MAX_LEN },
295 		.iterate_transfer_mask = BIT(0) | BIT(1),
296 		.transfer_count = 2,
297 		.transfers		= {
298 			{
299 				.tx_buf = TX(0),
300 				.rx_buf = RX(0),
301 				.delay = {
302 					.value = 1000,
303 					.unit = SPI_DELAY_UNIT_USECS,
304 				},
305 			},
306 			{
307 				.tx_buf = TX(0),
308 				.rx_buf = RX(0),
309 				.delay = {
310 					.value = 1000,
311 					.unit = SPI_DELAY_UNIT_USECS,
312 				},
313 			},
314 		},
315 	},
316 
317 	{ /* end of tests sequence */ }
318 };
319 
320 static int spi_loopback_test_probe(struct spi_device *spi)
321 {
322 	int ret;
323 
324 	if (loop_req || no_cs) {
325 		spi->mode |= loop_req ? SPI_LOOP : 0;
326 		spi->mode |= no_cs ? SPI_NO_CS : 0;
327 		ret = spi_setup(spi);
328 		if (ret) {
329 			dev_err(&spi->dev, "SPI setup with SPI_LOOP or SPI_NO_CS failed (%d)\n",
330 				ret);
331 			return ret;
332 		}
333 	}
334 
335 	dev_info(&spi->dev, "Executing spi-loopback-tests\n");
336 
337 	ret = spi_test_run_tests(spi, spi_tests);
338 
339 	dev_info(&spi->dev, "Finished spi-loopback-tests with return: %i\n",
340 		 ret);
341 
342 	return ret;
343 }
344 
345 /* non const match table to permit to change via a module parameter */
346 static struct of_device_id spi_loopback_test_of_match[] = {
347 	{ .compatible	= "linux,spi-loopback-test", },
348 	{ }
349 };
350 
351 /* allow to override the compatible string via a module_parameter */
352 module_param_string(compatible, spi_loopback_test_of_match[0].compatible,
353 		    sizeof(spi_loopback_test_of_match[0].compatible),
354 		    0000);
355 
356 MODULE_DEVICE_TABLE(of, spi_loopback_test_of_match);
357 
358 static struct spi_driver spi_loopback_test_driver = {
359 	.driver = {
360 		.name = "spi-loopback-test",
361 		.owner = THIS_MODULE,
362 		.of_match_table = spi_loopback_test_of_match,
363 	},
364 	.probe = spi_loopback_test_probe,
365 };
366 
367 module_spi_driver(spi_loopback_test_driver);
368 
369 MODULE_AUTHOR("Martin Sperl <kernel@martin.sperl.org>");
370 MODULE_DESCRIPTION("test spi_driver to check core functionality");
371 MODULE_LICENSE("GPL");
372 
373 /*-------------------------------------------------------------------------*/
374 
375 /* spi_test implementation */
376 
377 #define RANGE_CHECK(ptr, plen, start, slen) \
378 	((ptr >= start) && (ptr + plen <= start + slen))
379 
380 /* we allocate one page more, to allow for offsets */
381 #define SPI_TEST_MAX_SIZE_PLUS (SPI_TEST_MAX_SIZE + PAGE_SIZE)
382 
383 static void spi_test_print_hex_dump(char *pre, const void *ptr, size_t len)
384 {
385 	/* limit the hex_dump */
386 	if (len < 1024) {
387 		print_hex_dump(KERN_INFO, pre,
388 			       DUMP_PREFIX_OFFSET, 16, 1,
389 			       ptr, len, 0);
390 		return;
391 	}
392 	/* print head */
393 	print_hex_dump(KERN_INFO, pre,
394 		       DUMP_PREFIX_OFFSET, 16, 1,
395 		       ptr, 512, 0);
396 	/* print tail */
397 	pr_info("%s truncated - continuing at offset %04zx\n",
398 		pre, len - 512);
399 	print_hex_dump(KERN_INFO, pre,
400 		       DUMP_PREFIX_OFFSET, 16, 1,
401 		       ptr + (len - 512), 512, 0);
402 }
403 
404 static void spi_test_dump_message(struct spi_device *spi,
405 				  struct spi_message *msg,
406 				  bool dump_data)
407 {
408 	struct spi_transfer *xfer;
409 	int i;
410 	u8 b;
411 
412 	dev_info(&spi->dev, "  spi_msg@%pK\n", msg);
413 	if (msg->status)
414 		dev_info(&spi->dev, "    status:        %i\n",
415 			 msg->status);
416 	dev_info(&spi->dev, "    frame_length:  %i\n",
417 		 msg->frame_length);
418 	dev_info(&spi->dev, "    actual_length: %i\n",
419 		 msg->actual_length);
420 
421 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
422 		dev_info(&spi->dev, "    spi_transfer@%pK\n", xfer);
423 		dev_info(&spi->dev, "      len:    %i\n", xfer->len);
424 		dev_info(&spi->dev, "      tx_buf: %pK\n", xfer->tx_buf);
425 		if (dump_data && xfer->tx_buf)
426 			spi_test_print_hex_dump("          TX: ",
427 						xfer->tx_buf,
428 						xfer->len);
429 
430 		dev_info(&spi->dev, "      rx_buf: %pK\n", xfer->rx_buf);
431 		if (dump_data && xfer->rx_buf)
432 			spi_test_print_hex_dump("          RX: ",
433 						xfer->rx_buf,
434 						xfer->len);
435 		/* check for unwritten test pattern on rx_buf */
436 		if (xfer->rx_buf) {
437 			for (i = 0 ; i < xfer->len ; i++) {
438 				b = ((u8 *)xfer->rx_buf)[xfer->len - 1 - i];
439 				if (b != SPI_TEST_PATTERN_UNWRITTEN)
440 					break;
441 			}
442 			if (i)
443 				dev_info(&spi->dev,
444 					 "      rx_buf filled with %02x starts at offset: %i\n",
445 					 SPI_TEST_PATTERN_UNWRITTEN,
446 					 xfer->len - i);
447 		}
448 	}
449 }
450 
451 struct rx_ranges {
452 	struct list_head list;
453 	u8 *start;
454 	u8 *end;
455 };
456 
457 static int rx_ranges_cmp(void *priv, const struct list_head *a,
458 			 const struct list_head *b)
459 {
460 	struct rx_ranges *rx_a = list_entry(a, struct rx_ranges, list);
461 	struct rx_ranges *rx_b = list_entry(b, struct rx_ranges, list);
462 
463 	if (rx_a->start > rx_b->start)
464 		return 1;
465 	if (rx_a->start < rx_b->start)
466 		return -1;
467 	return 0;
468 }
469 
470 static int spi_check_rx_ranges(struct spi_device *spi,
471 			       struct spi_message *msg,
472 			       void *rx)
473 {
474 	struct spi_transfer *xfer;
475 	struct rx_ranges ranges[SPI_TEST_MAX_TRANSFERS], *r;
476 	int i = 0;
477 	LIST_HEAD(ranges_list);
478 	u8 *addr;
479 	int ret = 0;
480 
481 	/* loop over all transfers to fill in the rx_ranges */
482 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
483 		/* if there is no rx, then no check is needed */
484 		if (!xfer->rx_buf)
485 			continue;
486 		/* fill in the rx_range */
487 		if (RANGE_CHECK(xfer->rx_buf, xfer->len,
488 				rx, SPI_TEST_MAX_SIZE_PLUS)) {
489 			ranges[i].start = xfer->rx_buf;
490 			ranges[i].end = xfer->rx_buf + xfer->len;
491 			list_add(&ranges[i].list, &ranges_list);
492 			i++;
493 		}
494 	}
495 
496 	/* if no ranges, then we can return and avoid the checks...*/
497 	if (!i)
498 		return 0;
499 
500 	/* sort the list */
501 	list_sort(NULL, &ranges_list, rx_ranges_cmp);
502 
503 	/* and iterate over all the rx addresses */
504 	for (addr = rx; addr < (u8 *)rx + SPI_TEST_MAX_SIZE_PLUS; addr++) {
505 		/* if we are the DO not write pattern,
506 		 * then continue with the loop...
507 		 */
508 		if (*addr == SPI_TEST_PATTERN_DO_NOT_WRITE)
509 			continue;
510 
511 		/* check if we are inside a range */
512 		list_for_each_entry(r, &ranges_list, list) {
513 			/* if so then set to end... */
514 			if ((addr >= r->start) && (addr < r->end))
515 				addr = r->end;
516 		}
517 		/* second test after a (hopefull) translation */
518 		if (*addr == SPI_TEST_PATTERN_DO_NOT_WRITE)
519 			continue;
520 
521 		/* if still not found then something has modified too much */
522 		/* we could list the "closest" transfer here... */
523 		dev_err(&spi->dev,
524 			"loopback strangeness - rx changed outside of allowed range at: %pK\n",
525 			addr);
526 		/* do not return, only set ret,
527 		 * so that we list all addresses
528 		 */
529 		ret = -ERANGE;
530 	}
531 
532 	return ret;
533 }
534 
535 static int spi_test_check_elapsed_time(struct spi_device *spi,
536 				       struct spi_test *test)
537 {
538 	int i;
539 	unsigned long long estimated_time = 0;
540 	unsigned long long delay_usecs = 0;
541 
542 	for (i = 0; i < test->transfer_count; i++) {
543 		struct spi_transfer *xfer = test->transfers + i;
544 		unsigned long long nbits = (unsigned long long)BITS_PER_BYTE *
545 					   xfer->len;
546 
547 		delay_usecs += xfer->delay.value;
548 		if (!xfer->speed_hz)
549 			continue;
550 		estimated_time += div_u64(nbits * NSEC_PER_SEC, xfer->speed_hz);
551 	}
552 
553 	estimated_time += delay_usecs * NSEC_PER_USEC;
554 	if (test->elapsed_time < estimated_time) {
555 		dev_err(&spi->dev,
556 			"elapsed time %lld ns is shorter than minimum estimated time %lld ns\n",
557 			test->elapsed_time, estimated_time);
558 
559 		return -EINVAL;
560 	}
561 
562 	return 0;
563 }
564 
565 static int spi_test_check_loopback_result(struct spi_device *spi,
566 					  struct spi_message *msg,
567 					  void *tx, void *rx)
568 {
569 	struct spi_transfer *xfer;
570 	u8 rxb, txb;
571 	size_t i;
572 	int ret;
573 
574 	/* checks rx_buffer pattern are valid with loopback or without */
575 	if (check_ranges) {
576 		ret = spi_check_rx_ranges(spi, msg, rx);
577 		if (ret)
578 			return ret;
579 	}
580 
581 	/* if we run without loopback, then return now */
582 	if (!loopback)
583 		return 0;
584 
585 	/* if applicable to transfer check that rx_buf is equal to tx_buf */
586 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
587 		/* if there is no rx, then no check is needed */
588 		if (!xfer->len || !xfer->rx_buf)
589 			continue;
590 		/* so depending on tx_buf we need to handle things */
591 		if (xfer->tx_buf) {
592 			for (i = 0; i < xfer->len; i++) {
593 				txb = ((u8 *)xfer->tx_buf)[i];
594 				rxb = ((u8 *)xfer->rx_buf)[i];
595 				if (txb != rxb)
596 					goto mismatch_error;
597 			}
598 		} else {
599 			/* first byte received */
600 			txb = ((u8 *)xfer->rx_buf)[0];
601 			/* first byte may be 0 or xff */
602 			if (!((txb == 0) || (txb == 0xff))) {
603 				dev_err(&spi->dev,
604 					"loopback strangeness - we expect 0x00 or 0xff, but not 0x%02x\n",
605 					txb);
606 				return -EINVAL;
607 			}
608 			/* check that all bytes are identical */
609 			for (i = 1; i < xfer->len; i++) {
610 				rxb = ((u8 *)xfer->rx_buf)[i];
611 				if (rxb != txb)
612 					goto mismatch_error;
613 			}
614 		}
615 	}
616 
617 	return 0;
618 
619 mismatch_error:
620 	dev_err(&spi->dev,
621 		"loopback strangeness - transfer mismatch on byte %04zx - expected 0x%02x, but got 0x%02x\n",
622 		i, txb, rxb);
623 
624 	return -EINVAL;
625 }
626 
627 static int spi_test_translate(struct spi_device *spi,
628 			      void **ptr, size_t len,
629 			      void *tx, void *rx)
630 {
631 	size_t off;
632 
633 	/* return on null */
634 	if (!*ptr)
635 		return 0;
636 
637 	/* in the MAX_SIZE_HALF case modify the pointer */
638 	if (((size_t)*ptr) & SPI_TEST_MAX_SIZE_HALF)
639 		/* move the pointer to the correct range */
640 		*ptr += (SPI_TEST_MAX_SIZE_PLUS / 2) -
641 			SPI_TEST_MAX_SIZE_HALF;
642 
643 	/* RX range
644 	 * - we check against MAX_SIZE_PLUS to allow for automated alignment
645 	 */
646 	if (RANGE_CHECK(*ptr, len,  RX(0), SPI_TEST_MAX_SIZE_PLUS)) {
647 		off = *ptr - RX(0);
648 		*ptr = rx + off;
649 
650 		return 0;
651 	}
652 
653 	/* TX range */
654 	if (RANGE_CHECK(*ptr, len,  TX(0), SPI_TEST_MAX_SIZE_PLUS)) {
655 		off = *ptr - TX(0);
656 		*ptr = tx + off;
657 
658 		return 0;
659 	}
660 
661 	dev_err(&spi->dev,
662 		"PointerRange [%pK:%pK[ not in range [%pK:%pK[ or [%pK:%pK[\n",
663 		*ptr, *ptr + len,
664 		RX(0), RX(SPI_TEST_MAX_SIZE),
665 		TX(0), TX(SPI_TEST_MAX_SIZE));
666 
667 	return -EINVAL;
668 }
669 
670 static int spi_test_fill_pattern(struct spi_device *spi,
671 				 struct spi_test *test)
672 {
673 	struct spi_transfer *xfers = test->transfers;
674 	u8 *tx_buf;
675 	size_t count = 0;
676 	int i, j;
677 
678 #ifdef __BIG_ENDIAN
679 #define GET_VALUE_BYTE(value, index, bytes) \
680 	(value >> (8 * (bytes - 1 - count % bytes)))
681 #else
682 #define GET_VALUE_BYTE(value, index, bytes) \
683 	(value >> (8 * (count % bytes)))
684 #endif
685 
686 	/* fill all transfers with the pattern requested */
687 	for (i = 0; i < test->transfer_count; i++) {
688 		/* fill rx_buf with SPI_TEST_PATTERN_UNWRITTEN */
689 		if (xfers[i].rx_buf)
690 			memset(xfers[i].rx_buf, SPI_TEST_PATTERN_UNWRITTEN,
691 			       xfers[i].len);
692 		/* if tx_buf is NULL then skip */
693 		tx_buf = (u8 *)xfers[i].tx_buf;
694 		if (!tx_buf)
695 			continue;
696 		/* modify all the transfers */
697 		for (j = 0; j < xfers[i].len; j++, tx_buf++, count++) {
698 			/* fill tx */
699 			switch (test->fill_option) {
700 			case FILL_MEMSET_8:
701 				*tx_buf = test->fill_pattern;
702 				break;
703 			case FILL_MEMSET_16:
704 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
705 							 count, 2);
706 				break;
707 			case FILL_MEMSET_24:
708 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
709 							 count, 3);
710 				break;
711 			case FILL_MEMSET_32:
712 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
713 							 count, 4);
714 				break;
715 			case FILL_COUNT_8:
716 				*tx_buf = count;
717 				break;
718 			case FILL_COUNT_16:
719 				*tx_buf = GET_VALUE_BYTE(count, count, 2);
720 				break;
721 			case FILL_COUNT_24:
722 				*tx_buf = GET_VALUE_BYTE(count, count, 3);
723 				break;
724 			case FILL_COUNT_32:
725 				*tx_buf = GET_VALUE_BYTE(count, count, 4);
726 				break;
727 			case FILL_TRANSFER_BYTE_8:
728 				*tx_buf = j;
729 				break;
730 			case FILL_TRANSFER_BYTE_16:
731 				*tx_buf = GET_VALUE_BYTE(j, j, 2);
732 				break;
733 			case FILL_TRANSFER_BYTE_24:
734 				*tx_buf = GET_VALUE_BYTE(j, j, 3);
735 				break;
736 			case FILL_TRANSFER_BYTE_32:
737 				*tx_buf = GET_VALUE_BYTE(j, j, 4);
738 				break;
739 			case FILL_TRANSFER_NUM:
740 				*tx_buf = i;
741 				break;
742 			default:
743 				dev_err(&spi->dev,
744 					"unsupported fill_option: %i\n",
745 					test->fill_option);
746 				return -EINVAL;
747 			}
748 		}
749 	}
750 
751 	return 0;
752 }
753 
754 static int _spi_test_run_iter(struct spi_device *spi,
755 			      struct spi_test *test,
756 			      void *tx, void *rx)
757 {
758 	struct spi_message *msg = &test->msg;
759 	struct spi_transfer *x;
760 	int i, ret;
761 
762 	/* initialize message - zero-filled via static initialization */
763 	spi_message_init_no_memset(msg);
764 
765 	/* fill rx with the DO_NOT_WRITE pattern */
766 	memset(rx, SPI_TEST_PATTERN_DO_NOT_WRITE, SPI_TEST_MAX_SIZE_PLUS);
767 
768 	/* add the individual transfers */
769 	for (i = 0; i < test->transfer_count; i++) {
770 		x = &test->transfers[i];
771 
772 		/* patch the values of tx_buf */
773 		ret = spi_test_translate(spi, (void **)&x->tx_buf, x->len,
774 					 (void *)tx, rx);
775 		if (ret)
776 			return ret;
777 
778 		/* patch the values of rx_buf */
779 		ret = spi_test_translate(spi, &x->rx_buf, x->len,
780 					 (void *)tx, rx);
781 		if (ret)
782 			return ret;
783 
784 		/* and add it to the list */
785 		spi_message_add_tail(x, msg);
786 	}
787 
788 	/* fill in the transfer buffers with pattern */
789 	ret = spi_test_fill_pattern(spi, test);
790 	if (ret)
791 		return ret;
792 
793 	/* and execute */
794 	if (test->execute_msg)
795 		ret = test->execute_msg(spi, test, tx, rx);
796 	else
797 		ret = spi_test_execute_msg(spi, test, tx, rx);
798 
799 	/* handle result */
800 	if (ret == test->expected_return)
801 		return 0;
802 
803 	dev_err(&spi->dev,
804 		"test failed - test returned %i, but we expect %i\n",
805 		ret, test->expected_return);
806 
807 	if (ret)
808 		return ret;
809 
810 	/* if it is 0, as we expected something else,
811 	 * then return something special
812 	 */
813 	return -EFAULT;
814 }
815 
816 static int spi_test_run_iter(struct spi_device *spi,
817 			     const struct spi_test *testtemplate,
818 			     void *tx, void *rx,
819 			     size_t len,
820 			     size_t tx_off,
821 			     size_t rx_off
822 	)
823 {
824 	struct spi_test test;
825 	int i, tx_count, rx_count;
826 
827 	/* copy the test template to test */
828 	memcpy(&test, testtemplate, sizeof(test));
829 
830 	/* if iterate_transfer_mask is not set,
831 	 * then set it to first transfer only
832 	 */
833 	if (!(test.iterate_transfer_mask & (BIT(test.transfer_count) - 1)))
834 		test.iterate_transfer_mask = 1;
835 
836 	/* count number of transfers with tx/rx_buf != NULL */
837 	rx_count = tx_count = 0;
838 	for (i = 0; i < test.transfer_count; i++) {
839 		if (test.transfers[i].tx_buf)
840 			tx_count++;
841 		if (test.transfers[i].rx_buf)
842 			rx_count++;
843 	}
844 
845 	/* in some iteration cases warn and exit early,
846 	 * as there is nothing to do, that has not been tested already...
847 	 */
848 	if (tx_off && (!tx_count)) {
849 		dev_warn_once(&spi->dev,
850 			      "%s: iterate_tx_off configured with tx_buf==NULL - ignoring\n",
851 			      test.description);
852 		return 0;
853 	}
854 	if (rx_off && (!rx_count)) {
855 		dev_warn_once(&spi->dev,
856 			      "%s: iterate_rx_off configured with rx_buf==NULL - ignoring\n",
857 			      test.description);
858 		return 0;
859 	}
860 
861 	/* write out info */
862 	if (!(len || tx_off || rx_off)) {
863 		dev_info(&spi->dev, "Running test %s\n", test.description);
864 	} else {
865 		dev_info(&spi->dev,
866 			 "  with iteration values: len = %zu, tx_off = %zu, rx_off = %zu\n",
867 			 len, tx_off, rx_off);
868 	}
869 
870 	/* update in the values from iteration values */
871 	for (i = 0; i < test.transfer_count; i++) {
872 		/* only when bit in transfer mask is set */
873 		if (!(test.iterate_transfer_mask & BIT(i)))
874 			continue;
875 		test.transfers[i].len = len;
876 		if (test.transfers[i].tx_buf)
877 			test.transfers[i].tx_buf += tx_off;
878 		if (test.transfers[i].tx_buf)
879 			test.transfers[i].rx_buf += rx_off;
880 	}
881 
882 	/* and execute */
883 	return _spi_test_run_iter(spi, &test, tx, rx);
884 }
885 
886 /**
887  * spi_test_execute_msg - default implementation to run a test
888  *
889  * @spi: @spi_device on which to run the @spi_message
890  * @test: the test to execute, which already contains @msg
891  * @tx:   the tx buffer allocated for the test sequence
892  * @rx:   the rx buffer allocated for the test sequence
893  *
894  * Returns: error code of spi_sync as well as basic error checking
895  */
896 int spi_test_execute_msg(struct spi_device *spi, struct spi_test *test,
897 			 void *tx, void *rx)
898 {
899 	struct spi_message *msg = &test->msg;
900 	int ret = 0;
901 	int i;
902 
903 	/* only if we do not simulate */
904 	if (!simulate_only) {
905 		ktime_t start;
906 
907 		/* dump the complete message before and after the transfer */
908 		if (dump_messages == 3)
909 			spi_test_dump_message(spi, msg, true);
910 
911 		start = ktime_get();
912 		/* run spi message */
913 		ret = spi_sync(spi, msg);
914 		test->elapsed_time = ktime_to_ns(ktime_sub(ktime_get(), start));
915 		if (ret == -ETIMEDOUT) {
916 			dev_info(&spi->dev,
917 				 "spi-message timed out - rerunning...\n");
918 			/* rerun after a few explicit schedules */
919 			for (i = 0; i < 16; i++)
920 				schedule();
921 			ret = spi_sync(spi, msg);
922 		}
923 		if (ret) {
924 			dev_err(&spi->dev,
925 				"Failed to execute spi_message: %i\n",
926 				ret);
927 			goto exit;
928 		}
929 
930 		/* do some extra error checks */
931 		if (msg->frame_length != msg->actual_length) {
932 			dev_err(&spi->dev,
933 				"actual length differs from expected\n");
934 			ret = -EIO;
935 			goto exit;
936 		}
937 
938 		/* run rx-buffer tests */
939 		ret = spi_test_check_loopback_result(spi, msg, tx, rx);
940 		if (ret)
941 			goto exit;
942 
943 		ret = spi_test_check_elapsed_time(spi, test);
944 	}
945 
946 	/* if requested or on error dump message (including data) */
947 exit:
948 	if (dump_messages || ret)
949 		spi_test_dump_message(spi, msg,
950 				      (dump_messages >= 2) || (ret));
951 
952 	return ret;
953 }
954 EXPORT_SYMBOL_GPL(spi_test_execute_msg);
955 
956 /**
957  * spi_test_run_test - run an individual spi_test
958  *                     including all the relevant iterations on:
959  *                     length and buffer alignment
960  *
961  * @spi:  the spi_device to send the messages to
962  * @test: the test which we need to execute
963  * @tx:   the tx buffer allocated for the test sequence
964  * @rx:   the rx buffer allocated for the test sequence
965  *
966  * Returns: status code of spi_sync or other failures
967  */
968 
969 int spi_test_run_test(struct spi_device *spi, const struct spi_test *test,
970 		      void *tx, void *rx)
971 {
972 	int idx_len;
973 	size_t len;
974 	size_t tx_align, rx_align;
975 	int ret;
976 
977 	/* test for transfer limits */
978 	if (test->transfer_count >= SPI_TEST_MAX_TRANSFERS) {
979 		dev_err(&spi->dev,
980 			"%s: Exceeded max number of transfers with %i\n",
981 			test->description, test->transfer_count);
982 		return -E2BIG;
983 	}
984 
985 	/* setting up some values in spi_message
986 	 * based on some settings in spi_master
987 	 * some of this can also get done in the run() method
988 	 */
989 
990 	/* iterate over all the iterable values using macros
991 	 * (to make it a bit more readable...
992 	 */
993 #define FOR_EACH_ALIGNMENT(var)						\
994 	for (var = 0;							\
995 	    var < (test->iterate_##var ?				\
996 			(spi->master->dma_alignment ?			\
997 			 spi->master->dma_alignment :			\
998 			 test->iterate_##var) :				\
999 			1);						\
1000 	    var++)
1001 
1002 	for (idx_len = 0; idx_len < SPI_TEST_MAX_ITERATE &&
1003 	     (len = test->iterate_len[idx_len]) != -1; idx_len++) {
1004 		FOR_EACH_ALIGNMENT(tx_align) {
1005 			FOR_EACH_ALIGNMENT(rx_align) {
1006 				/* and run the iteration */
1007 				ret = spi_test_run_iter(spi, test,
1008 							tx, rx,
1009 							len,
1010 							tx_align,
1011 							rx_align);
1012 				if (ret)
1013 					return ret;
1014 			}
1015 		}
1016 	}
1017 
1018 	return 0;
1019 }
1020 EXPORT_SYMBOL_GPL(spi_test_run_test);
1021 
1022 /**
1023  * spi_test_run_tests - run an array of spi_messages tests
1024  * @spi: the spi device on which to run the tests
1025  * @tests: NULL-terminated array of @spi_test
1026  *
1027  * Returns: status errors as per @spi_test_run_test()
1028  */
1029 
1030 int spi_test_run_tests(struct spi_device *spi,
1031 		       struct spi_test *tests)
1032 {
1033 	char *rx = NULL, *tx = NULL;
1034 	int ret = 0, count = 0;
1035 	struct spi_test *test;
1036 
1037 	/* allocate rx/tx buffers of 128kB size without devm
1038 	 * in the hope that is on a page boundary
1039 	 */
1040 	if (use_vmalloc)
1041 		rx = vmalloc(SPI_TEST_MAX_SIZE_PLUS);
1042 	else
1043 		rx = kzalloc(SPI_TEST_MAX_SIZE_PLUS, GFP_KERNEL);
1044 	if (!rx)
1045 		return -ENOMEM;
1046 
1047 
1048 	if (use_vmalloc)
1049 		tx = vmalloc(SPI_TEST_MAX_SIZE_PLUS);
1050 	else
1051 		tx = kzalloc(SPI_TEST_MAX_SIZE_PLUS, GFP_KERNEL);
1052 	if (!tx) {
1053 		ret = -ENOMEM;
1054 		goto err_tx;
1055 	}
1056 
1057 	/* now run the individual tests in the table */
1058 	for (test = tests, count = 0; test->description[0];
1059 	     test++, count++) {
1060 		/* only run test if requested */
1061 		if ((run_only_test > -1) && (count != run_only_test))
1062 			continue;
1063 		/* run custom implementation */
1064 		if (test->run_test)
1065 			ret = test->run_test(spi, test, tx, rx);
1066 		else
1067 			ret = spi_test_run_test(spi, test, tx, rx);
1068 		if (ret)
1069 			goto out;
1070 		/* add some delays so that we can easily
1071 		 * detect the individual tests when using a logic analyzer
1072 		 * we also add scheduling to avoid potential spi_timeouts...
1073 		 */
1074 		mdelay(100);
1075 		schedule();
1076 	}
1077 
1078 out:
1079 	kvfree(tx);
1080 err_tx:
1081 	kvfree(rx);
1082 	return ret;
1083 }
1084 EXPORT_SYMBOL_GPL(spi_test_run_tests);
1085