aboutsummaryrefslogtreecommitdiffstats
path: root/ni845x_spi.c
blob: 765da8a6ec07d6c6d857e22ffcdd9238f3530fac (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
/*
 * This file is part of the flashrom project.
 *
 * Copyright (C) 2018 Miklós Márton martonmiklosqdev@gmail.com
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <ctype.h>
#include <inttypes.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <ni845x.h>
#include <unistd.h>

#include "flash.h"
#include "programmer.h"
#include "spi.h"

#define NI845x_FIND_DEVICE_NO_DEVICE_FOUND			-301701

enum USB845x_type {
	USB8451 = 0x7166,
	USB8452 = 0x7514,
	Unknown_NI845X_Device
};

enum voltage_coerce_mode {
	USE_LOWER,
	USE_HIGHER
};

static unsigned char CS_number;	// use chip select 0 as default
static enum USB845x_type device_pid = Unknown_NI845X_Device;

static uInt32 device_handle;
static NiHandle configuration_handle;
static uint16_t io_voltage_in_mV;
static bool ignore_io_voltage_limits;

// USB-8452 supported voltages, keep this array in ascending order!
static const uint8_t usb8452_io_voltages_in_100mV[5] = {
	kNi845x12Volts,
	kNi845x15Volts,
	kNi845x18Volts,
	kNi845x25Volts,
	kNi845x33Volts
};

/* Copied from dediprog.c */
/* Might be useful for other USB devices as well. static for now. */
static int parse_voltage(char *voltage)
{
	char *tmp = NULL;
	int i;
	int millivolt = 0, fraction = 0;

	if (!voltage || !strlen(voltage)) {
		msg_perr("Empty voltage= specified.\n");
		return -1;
	}
	millivolt = (int)strtol(voltage, &tmp, 0);
	voltage = tmp;
	/* Handle "," and "." as decimal point. Everything after it is assumed
	 * to be in decimal notation.
	 */
	if ((*voltage == '.') || (*voltage == ',')) {
		voltage++;
		for (i = 0; i < 3; i++) {
			fraction *= 10;
			/* Don't advance if the current character is invalid,
			 * but continue multiplying.
			 */
			if ((*voltage < '0') || (*voltage > '9'))
				continue;
			fraction += *voltage - '0';
			voltage++;
		}
		/* Throw away remaining digits. */
		voltage += strspn(voltage, "0123456789");
	}
	/* The remaining string must be empty or "mV" or "V". */
	tolower_string(voltage);

	/* No unit or "V". */
	if ((*voltage == '\0') || !strncmp(voltage, "v", 1)) {
		millivolt *= 1000;
		millivolt += fraction;
	} else if (!strncmp(voltage, "mv", 2) || !strncmp(voltage, "millivolt", 9)) {
		/* No adjustment. fraction is discarded. */
	} else {
		/* Garbage at the end of the string. */
		msg_perr("Garbage voltage= specified.\n");
		return -1;
	}
	return millivolt;
}

static void ni845x_report_error(const char *const func, const int32 err)
{
	static char buf[1024];

	ni845xStatusToString(err, sizeof(buf), buf);
	msg_perr("%s failed with: %s (%d)\n", func, buf, (int)err);
}

static void ni845x_report_warning(const char *const func, const int32 err)
{
	static char buf[1024];

	ni845xStatusToString(err, sizeof(buf), buf);
	msg_pwarn("%s failed with: %s (%d)\n", func, buf, (int)err);
}

/**
 * @brief ni845x_spi_open_resource
 * @param resource_handle the resource handle returned by the ni845xFindDevice or ni845xFindDeviceNext
 * @param opened_handle the opened handle from the ni845xOpen
 * @return the 0 on successful competition, negative error code on failure positive code on warning
 */
static int32 ni845x_spi_open_resource(char *resource_handle, uInt32 *opened_handle)
{
	// NI-845x driver loads the FPGA bitfile at the first time
	// which can take couple seconds
	if (device_pid == USB8452)
		msg_pwarn("Opening NI-8452, this might take a while for the first time\n");

	int32 tmp = ni845xOpen(resource_handle, opened_handle);

	if (tmp < 0)
		ni845x_report_error("ni845xOpen", tmp);
	else if (tmp > 0)
		ni845x_report_warning("ni845xOpen", tmp);
	return tmp;
}

/**
 * @param serial a null terminated string containing the serial number of the specific device or NULL
 * @return the 0 on successful completition, negative error code on failure
 */
static int ni845x_spi_open(const char *serial, uInt32 *return_handle)
{
	char resource_name[256];
	NiHandle device_find_handle;
	uInt32 found_devices_count = 0;
	int32 tmp = 0;

	unsigned int vid, pid, usb_bus;
	unsigned long int serial_as_number;
	int ret = -1;

	tmp = ni845xFindDevice(resource_name, &device_find_handle, &found_devices_count);
	if (tmp != 0) {
		// supress warning if no device found
		if (tmp != NI845x_FIND_DEVICE_NO_DEVICE_FOUND)
			ni845x_report_error("ni845xFindDevice", tmp);
		return -1;
	}

	for (; found_devices_count; --found_devices_count) {
		// Read the serial number and the PID here
		// VISA resource name format example:
		// USB0::0x3923::0x7514::DEADBEEF::RAW
		// where the 0x7514 is the PID
		// and the DEADBEEF is the serial of the device
		if (sscanf(resource_name,
			   "USB%u::0x%04X::0x%04X::%08lX::RAW",
			   &usb_bus, &vid, &pid, &serial_as_number) != 4) {
			// malformed resource string detected
			msg_pwarn("Warning: Unable to parse the %s NI-845x resource string.\n",
				  resource_name);
			msg_pwarn("Please report a bug at flashrom@flashrom.org\n");
			continue;
		}

		device_pid = pid;

		if (!serial || strtol(serial, NULL, 16) == serial_as_number)
			break;

		if (found_devices_count > 1) {
			tmp = ni845xFindDeviceNext(device_find_handle, resource_name);
			if (tmp) {
				ni845x_report_error("ni845xFindDeviceNext", tmp);
				goto _close_ret;
			}
		}
	}

	if (found_devices_count)
		ret = ni845x_spi_open_resource(resource_name, return_handle);

_close_ret:
	tmp = ni845xCloseFindDeviceHandle(device_find_handle);
	if (tmp) {
		ni845x_report_error("ni845xCloseFindDeviceHandle", tmp);
		return -1;
	}
	return ret;
}

/**
 * @brief usb8452_spi_set_io_voltage sets the IO voltage for the USB-8452 devices
 * @param requested_io_voltage_mV the desired IO voltage in mVolts
 * @param set_io_voltage_mV the IO voltage which was set in mVolts
 * @param coerce_mode if set to USE_LOWER the closest supported IO voltage which is lower or equal to
 * the requested_io_voltage_mV will be selected. Otherwise the next closest supported voltage will be choosen
 * which is higher or equal to the requested_io_voltage_mV.
 * @return 0 on success, negative on error, positive on warning
 */
static int usb8452_spi_set_io_voltage(uint16_t requested_io_voltage_mV,
				      uint16_t *set_io_voltage_mV,
				      enum voltage_coerce_mode coerce_mode)
{
	int i = 0;
	uint8_t selected_voltage_100mV = 0;
	uint8_t requested_io_voltage_100mV = 0;

	if (device_pid == USB8451) {
		io_voltage_in_mV = 3300;
		msg_pwarn("USB-8451 does not support the changing of the SPI IO voltage\n");
		return 0;
	}

	// limit the IO voltage to 3.3V
	if (requested_io_voltage_mV > 3300) {
		msg_pinfo("USB-8452 maximum IO voltage is 3.3V\n");
		return -1;
	}
	requested_io_voltage_100mV = (requested_io_voltage_mV / 100.0f);

	// usb8452_io_voltages_in_100mV contains the supported voltage levels in increasing order
	for (i = (ARRAY_SIZE(usb8452_io_voltages_in_100mV) - 1); i > 0; --i) {
		if (requested_io_voltage_100mV >= usb8452_io_voltages_in_100mV[i])
			break;
	}

	if (coerce_mode == USE_LOWER) {
		if (requested_io_voltage_100mV < usb8452_io_voltages_in_100mV[0]) {
			msg_perr("Unable to set the USB-8452 IO voltage below %.1fV "
				 "(the minimum supported IO voltage is %.1fV)\n",
				 (float)requested_io_voltage_100mV / 10.0f,
				 (float)usb8452_io_voltages_in_100mV[0] / 10.0f);
			return -1;
		}
		selected_voltage_100mV = usb8452_io_voltages_in_100mV[i];
	} else {
		if (i == ARRAY_SIZE(usb8452_io_voltages_in_100mV) - 1)
			selected_voltage_100mV = usb8452_io_voltages_in_100mV[i];
		else
			selected_voltage_100mV = usb8452_io_voltages_in_100mV[i + 1];
	}

	if (requested_io_voltage_100mV < usb8452_io_voltages_in_100mV[0]) {
		/* unsupported / would have to round up */
		msg_pwarn("The USB-8452 does not support the %.1fV IO voltage\n",
			  requested_io_voltage_mV / 1000.0f);
		selected_voltage_100mV = kNi845x12Volts;
		msg_pwarn("The output voltage is set to 1.2V (this is the lowest voltage)\n");
		msg_pwarn("Supported IO voltages:\n");
		for (i = 0; i < ARRAY_SIZE(usb8452_io_voltages_in_100mV); i++) {
			msg_pwarn("%.1fV", (float)usb8452_io_voltages_in_100mV[i] / 10.0f);
			if (i != ARRAY_SIZE(usb8452_io_voltages_in_100mV) - 1)
				msg_pwarn(", ");
		}
		msg_pwarn("\n");
	} else if (selected_voltage_100mV != requested_io_voltage_100mV) {
		/* we rounded down/up */
		msg_pwarn("USB-8452 IO voltage forced to: %.1f V\n",
			  (float)selected_voltage_100mV / 10.0f);
	} else {
		/* exact match */
		msg_pinfo("USB-8452 IO voltage set to: %.1f V\n",
			  (float)selected_voltage_100mV / 10.0f);
	}

	if (set_io_voltage_mV)
		*set_io_voltage_mV = (selected_voltage_100mV * 100);

	i = ni845xSetIoVoltageLevel(device_handle, selected_voltage_100mV);
	if (i != 0) {
		ni845x_report_error("ni845xSetIoVoltageLevel", i);
		return -1;
	}
	return 0;
}

/**
 * @brief ni845x_spi_set_speed sets the SPI SCK speed
 * @param SCK_freq_in_KHz SCK speed in KHz
 * @return
 */
static int ni845x_spi_set_speed(uint16_t SCK_freq_in_KHz)
{
	int32 i = ni845xSpiConfigurationSetClockRate(configuration_handle, SCK_freq_in_KHz);
	uInt16 clock_freq_read_KHz;

	if (i != 0) {
		ni845x_report_error("ni845xSpiConfigurationSetClockRate", i);
		return -1;
	}

	// read back the clock frequency and notify the user if it is not the same as it was requested
	i = ni845xSpiConfigurationGetClockRate(configuration_handle, &clock_freq_read_KHz);
	if (i != 0) {
		ni845x_report_error("ni845xSpiConfigurationGetClockRate", i);
		return -1;
	}

	if (clock_freq_read_KHz != SCK_freq_in_KHz) {
		msg_pinfo("SPI clock frequency forced to: %d KHz (requested: %d KHz)\n",
			  (int)clock_freq_read_KHz, (int)SCK_freq_in_KHz);
	} else {
		msg_pinfo("SPI clock frequency set to: %d KHz\n", (int)SCK_freq_in_KHz);
	}
	return 0;
}

/**
 * @brief ni845x_spi_print_available_devices prints a list of the available devices
 */
static void ni845x_spi_print_available_devices(void)
{
	char resource_handle[256], device_type_string[16];
	NiHandle device_find_handle;
	uInt32 found_devices_count = 0;
	int32 tmp = 0;
	unsigned int pid, vid, usb_bus;
	unsigned long int serial_as_number;

	tmp = ni845xFindDevice(resource_handle, &device_find_handle, &found_devices_count);
	if (tmp != 0) {
		// supress warning if no device found
		if (tmp != NI845x_FIND_DEVICE_NO_DEVICE_FOUND)
			ni845x_report_error("ni845xFindDevice", tmp);
		return;
	}

	if (found_devices_count) {
		msg_pinfo("Available devices:\n");
		do {
			tmp = sscanf(resource_handle, "USB%d::0x%04X::0x%04X::%08lX::RAW",
				     &usb_bus, &vid, &pid, &serial_as_number);
			if (tmp == 4) {
				switch (pid) {
				case USB8451:
					snprintf(device_type_string,
							 ARRAY_SIZE(device_type_string), "USB-8451");
					break;
				case USB8452:
					snprintf(device_type_string,
							 ARRAY_SIZE(device_type_string), "USB-8452");
					break;
				default:
					snprintf(device_type_string,
							 ARRAY_SIZE(device_type_string), "Unknown device");
					break;
				}
				msg_pinfo("- %lX (%s)\n", serial_as_number, device_type_string);

				found_devices_count--;
				if (found_devices_count) {
					tmp = ni845xFindDeviceNext(device_find_handle, resource_handle);
					if (tmp)
						ni845x_report_error("ni845xFindDeviceNext", tmp);
				}
			}
		} while (found_devices_count);
	}

	tmp = ni845xCloseFindDeviceHandle(device_find_handle);
	if (tmp)
		ni845x_report_error("ni845xCloseFindDeviceHandle", tmp);
}

static int ni845x_spi_shutdown(void *data)
{
	int32 ret = 0;

	if (configuration_handle != 0) {
		ret = ni845xSpiConfigurationClose(configuration_handle);
		if (ret)
			ni845x_report_error("ni845xSpiConfigurationClose", ret);
	}

	if (device_handle != 0) {
		ret = ni845xClose(device_handle);
		if (ret)
			ni845x_report_error("ni845xClose", ret);
	}
	return 0;
}

static void ni845x_warn_over_max_voltage(const struct flashctx *flash)
{
	if (device_pid == USB8451) {
		msg_pwarn("The %s chip maximum voltage is %.1fV, while the USB-8451 "
			  "IO voltage levels are 3.3V.\n"
			  "Ignoring this because ignore_io_voltage_limits parameter is set.\n",
			 flash->chip->name,
			 flash->chip->voltage.max / 1000.0f);
	} else if (device_pid == USB8452) {
		msg_pwarn("The %s chip maximum voltage is %.1fV, while the USB-8452 "
			  "IO voltage is set to %.1fV.\n"
			  "Ignoring this because ignore_io_voltage_limits parameter is set.\n",
			  flash->chip->name,
			  flash->chip->voltage.max / 1000.0f,
			  io_voltage_in_mV / 1000.0f);
	}
}

static int ni845x_spi_io_voltage_check(const struct flashctx *flash)
{
	static bool first_transmit = true;

	if (first_transmit && flash->chip) {
		first_transmit = false;
		if (io_voltage_in_mV > flash->chip->voltage.max) {
			if (ignore_io_voltage_limits) {
				ni845x_warn_over_max_voltage(flash);
				return 0;
			}

			if (device_pid == USB8451) {
				msg_perr("The %s chip maximum voltage is %.1fV, while the USB-8451 "
					 "IO voltage levels are 3.3V.\nAborting operations\n",
					 flash->chip->name,
					 flash->chip->voltage.max / 1000.0f);
				return -1;
			} else if (device_pid == USB8452) {
				msg_perr("Lowering IO voltage because the %s chip maximum voltage is %.1fV, "
					 "(%.1fV was set)\n",
					 flash->chip->name,
					 flash->chip->voltage.max / 1000.0f,
					 io_voltage_in_mV / 1000.0f);
				if (usb8452_spi_set_io_voltage(flash->chip->voltage.max,
							       &io_voltage_in_mV,
							       USE_LOWER)) {
					msg_perr("Unable to lower the IO voltage below "
						 "the chip's maximum voltage\n");
					return -1;
				}
			}
		} else if (io_voltage_in_mV < flash->chip->voltage.min) {
			if (device_pid == USB8451) {
				msg_pwarn("Flash operations might be unreliable, because the %s chip's "
					  "minimum voltage is %.1fV, while the USB-8451's "
					  "IO voltage levels are 3.3V.\n",
					  flash->chip->name,
					  flash->chip->voltage.min / 1000.0f);
				return ignore_io_voltage_limits ? 0 : -1;
			} else if (device_pid == USB8452) {
				msg_pwarn("Raising the IO voltage because the %s chip's "
					  "minimum voltage is %.1fV, "
					  "(%.1fV was set)\n",
					  flash->chip->name,
					  flash->chip->voltage.min / 1000.0f,
					  io_voltage_in_mV / 1000.0f);
				if (usb8452_spi_set_io_voltage(flash->chip->voltage.min,
							       &io_voltage_in_mV,
							       USE_HIGHER)) {
					msg_pwarn("Unable to raise the IO voltage above the chip's "
						  "minimum voltage\n"
						  "Flash operations might be unreliable.\n");
					return ignore_io_voltage_limits ? 0 : -1;
				}
			}
		}
	}
	return 0;
}

static int ni845x_spi_transmit(struct flashctx *flash,
			       unsigned int write_cnt,
			       unsigned int read_cnt,
			       const unsigned char *write_arr,
			       unsigned char *read_arr)
{
	uInt32 read_size = 0;
	uInt8 *transfer_buffer = NULL;
	int32 ret = 0;

	if (ni845x_spi_io_voltage_check(flash))
		return -1;

	transfer_buffer = calloc(write_cnt + read_cnt, sizeof(uInt8));
	if (transfer_buffer == NULL) {
		msg_gerr("Memory allocation failed!\n");
		return -1;
	}

	memcpy(transfer_buffer, write_arr, write_cnt);

	ret = ni845xSpiWriteRead(device_handle,
				 configuration_handle,
				 (write_cnt + read_cnt), transfer_buffer, &read_size, transfer_buffer);
	if (ret < 0) {
		// Negative specifies an error, meaning the function did not perform the expected behavior.
		ni845x_report_error("ni845xSpiWriteRead", ret);
		free(transfer_buffer);
		return -1;
	} else if (ret > 0) {
		// Positive specifies a warning, meaning the function performed as expected,
		// but a condition arose that might require attention.
		ni845x_report_warning("ni845xSpiWriteRead", ret);
	}

	if (read_cnt != 0 && read_arr != NULL) {
		if ((read_cnt + write_cnt) != read_size) {
			msg_perr("%s: expected and returned read count mismatch: %u expected, %ld recieved\n",
					 __func__, read_cnt, read_size);
			free(transfer_buffer);
			return -1;
		}
		memcpy(read_arr, &transfer_buffer[write_cnt], read_cnt);
	}
	free(transfer_buffer);
	return 0;
}

static const struct spi_master spi_programmer_ni845x = {
	.max_data_read = MAX_DATA_READ_UNLIMITED,
	.max_data_write = MAX_DATA_WRITE_UNLIMITED,
	.command = ni845x_spi_transmit,
	.multicommand = default_spi_send_multicommand,
	.read = default_spi_read,
	.write_256 = default_spi_write_256,
	.write_aai = default_spi_write_aai,
};

int ni845x_spi_init(void)
{
	char *speed_str = NULL;
	char *CS_str = NULL;
	char *voltage = NULL;
	char *endptr = NULL;
	int requested_io_voltage_mV = 1200;     // default the IO voltage to 1.2V
	int spi_speed_KHz = 1000;		// selecting 1 MHz SCK is a good bet
	char *serial_number = NULL;		// by default open the first connected device
	char *ignore_io_voltage_limits_str = NULL;
	int32 tmp = 0;

	// read the cs parameter (which Chip select should we use)
	CS_str = extract_programmer_param("cs");
	if (CS_str) {
		CS_number = CS_str[0] - '0';
		free(CS_str);
		if (strlen(CS_str) > 1 || CS_number < 0 || 7 < CS_number) {
			msg_perr("Only CS 0-7 supported\n");
			return 1;
		}
	}

	voltage = extract_programmer_param("voltage");
	if (voltage != NULL) {
		requested_io_voltage_mV = parse_voltage(voltage);
		free(voltage);
		if (requested_io_voltage_mV < 0)
			return 1;
	}

	serial_number = extract_programmer_param("serial");

	speed_str = extract_programmer_param("spispeed");
	if (speed_str) {
		spi_speed_KHz = strtoul(speed_str, &endptr, 0);
		if (*endptr) {
			msg_perr("The spispeed parameter passed with invalid format: %s\n",
				 speed_str);
			msg_perr("Please pass the parameter with a simple number in kHz\n");
			return 1;
		}
		free(speed_str);
	}

	ignore_io_voltage_limits = false;
	ignore_io_voltage_limits_str = extract_programmer_param("ignore_io_voltage_limits");
	if (ignore_io_voltage_limits_str
		&& strcmp(ignore_io_voltage_limits_str, "yes") == 0) {
		ignore_io_voltage_limits = true;
	}

	if (ni845x_spi_open(serial_number, &device_handle)) {
		if (serial_number) {
			msg_pinfo("Could not find any connected NI USB-8451/8452 with serialnumber: %s!\n",
				  serial_number);
			ni845x_spi_print_available_devices();
			msg_pinfo("Check the S/N field on the bottom of the device,\n"
				  "or use 'lsusb -v -d 3923:7166 | grep Serial' for USB-8451\n"
				  "or 'lsusb -v -d 3923:7514 | grep Serial' for USB-8452\n");
			free(serial_number);
		} else {
			msg_pinfo("Could not find any connected NI USB-845x device!\n");
		}
		return 1;
	}
	free(serial_number);

	// open the SPI config handle
	tmp = ni845xSpiConfigurationOpen(&configuration_handle);
	if (tmp != 0) {
		ni845x_report_error("ni845xSpiConfigurationOpen", tmp);
		ni845x_spi_shutdown(NULL);
		return 1;
	}

	if (usb8452_spi_set_io_voltage(requested_io_voltage_mV, &io_voltage_in_mV, USE_LOWER) < 0) {
		ni845x_spi_shutdown(NULL);
		return 1;	// no alert here usb8452_spi_set_io_voltage already printed that
	}

	if (ni845x_spi_set_speed(spi_speed_KHz)) {
		msg_perr("Unable to set SPI speed\n");
		ni845x_spi_shutdown(NULL);
		return 1;
	}

	if (register_shutdown(ni845x_spi_shutdown, NULL)) {
		ni845x_spi_shutdown(NULL);
		return 1;
	}

	register_spi_master(&spi_programmer_ni845x);

	return 0;
}