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Based on kernel version 3.16. Page generated on 2014-08-06 21:41 EST.

1	/*
2	 * SPI testing utility (using spidev driver)
3	 *
4	 * Copyright (c) 2007  MontaVista Software, Inc.
5	 * Copyright (c) 2007  Anton Vorontsov <avorontsov@ru.mvista.com>
6	 *
7	 * This program is free software; you can redistribute it and/or modify
8	 * it under the terms of the GNU General Public License as published by
9	 * the Free Software Foundation; either version 2 of the License.
10	 *
11	 * Cross-compile with cross-gcc -I/path/to/cross-kernel/include
12	 */
13	
14	#include <stdint.h>
15	#include <unistd.h>
16	#include <stdio.h>
17	#include <stdlib.h>
18	#include <getopt.h>
19	#include <fcntl.h>
20	#include <sys/ioctl.h>
21	#include <linux/types.h>
22	#include <linux/spi/spidev.h>
23	
24	#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
25	
26	static void pabort(const char *s)
27	{
28		perror(s);
29		abort();
30	}
31	
32	static const char *device = "/dev/spidev1.1";
33	static uint32_t mode;
34	static uint8_t bits = 8;
35	static uint32_t speed = 500000;
36	static uint16_t delay;
37	
38	static void transfer(int fd)
39	{
40		int ret;
41		uint8_t tx[] = {
42			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
43			0x40, 0x00, 0x00, 0x00, 0x00, 0x95,
44			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
45			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
46			0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
47			0xDE, 0xAD, 0xBE, 0xEF, 0xBA, 0xAD,
48			0xF0, 0x0D,
49		};
50		uint8_t rx[ARRAY_SIZE(tx)] = {0, };
51		struct spi_ioc_transfer tr = {
52			.tx_buf = (unsigned long)tx,
53			.rx_buf = (unsigned long)rx,
54			.len = ARRAY_SIZE(tx),
55			.delay_usecs = delay,
56			.speed_hz = speed,
57			.bits_per_word = bits,
58		};
59	
60		if (mode & SPI_TX_QUAD)
61			tr.tx_nbits = 4;
62		else if (mode & SPI_TX_DUAL)
63			tr.tx_nbits = 2;
64		if (mode & SPI_RX_QUAD)
65			tr.rx_nbits = 4;
66		else if (mode & SPI_RX_DUAL)
67			tr.rx_nbits = 2;
68		if (!(mode & SPI_LOOP)) {
69			if (mode & (SPI_TX_QUAD | SPI_TX_DUAL))
70				tr.rx_buf = 0;
71			else if (mode & (SPI_RX_QUAD | SPI_RX_DUAL))
72				tr.tx_buf = 0;
73		}
74	
75		ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
76		if (ret < 1)
77			pabort("can't send spi message");
78	
79		for (ret = 0; ret < ARRAY_SIZE(tx); ret++) {
80			if (!(ret % 6))
81				puts("");
82			printf("%.2X ", rx[ret]);
83		}
84		puts("");
85	}
86	
87	static void print_usage(const char *prog)
88	{
89		printf("Usage: %s [-DsbdlHOLC3]\n", prog);
90		puts("  -D --device   device to use (default /dev/spidev1.1)\n"
91		     "  -s --speed    max speed (Hz)\n"
92		     "  -d --delay    delay (usec)\n"
93		     "  -b --bpw      bits per word \n"
94		     "  -l --loop     loopback\n"
95		     "  -H --cpha     clock phase\n"
96		     "  -O --cpol     clock polarity\n"
97		     "  -L --lsb      least significant bit first\n"
98		     "  -C --cs-high  chip select active high\n"
99		     "  -3 --3wire    SI/SO signals shared\n"
100		     "  -N --no-cs    no chip select\n"
101		     "  -R --ready    slave pulls low to pause\n"
102		     "  -2 --dual     dual transfer\n"
103		     "  -4 --quad     quad transfer\n");
104		exit(1);
105	}
106	
107	static void parse_opts(int argc, char *argv[])
108	{
109		while (1) {
110			static const struct option lopts[] = {
111				{ "device",  1, 0, 'D' },
112				{ "speed",   1, 0, 's' },
113				{ "delay",   1, 0, 'd' },
114				{ "bpw",     1, 0, 'b' },
115				{ "loop",    0, 0, 'l' },
116				{ "cpha",    0, 0, 'H' },
117				{ "cpol",    0, 0, 'O' },
118				{ "lsb",     0, 0, 'L' },
119				{ "cs-high", 0, 0, 'C' },
120				{ "3wire",   0, 0, '3' },
121				{ "no-cs",   0, 0, 'N' },
122				{ "ready",   0, 0, 'R' },
123				{ "dual",    0, 0, '2' },
124				{ "quad",    0, 0, '4' },
125				{ NULL, 0, 0, 0 },
126			};
127			int c;
128	
129			c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR24", lopts, NULL);
130	
131			if (c == -1)
132				break;
133	
134			switch (c) {
135			case 'D':
136				device = optarg;
137				break;
138			case 's':
139				speed = atoi(optarg);
140				break;
141			case 'd':
142				delay = atoi(optarg);
143				break;
144			case 'b':
145				bits = atoi(optarg);
146				break;
147			case 'l':
148				mode |= SPI_LOOP;
149				break;
150			case 'H':
151				mode |= SPI_CPHA;
152				break;
153			case 'O':
154				mode |= SPI_CPOL;
155				break;
156			case 'L':
157				mode |= SPI_LSB_FIRST;
158				break;
159			case 'C':
160				mode |= SPI_CS_HIGH;
161				break;
162			case '3':
163				mode |= SPI_3WIRE;
164				break;
165			case 'N':
166				mode |= SPI_NO_CS;
167				break;
168			case 'R':
169				mode |= SPI_READY;
170				break;
171			case '2':
172				mode |= SPI_TX_DUAL;
173				break;
174			case '4':
175				mode |= SPI_TX_QUAD;
176				break;
177			default:
178				print_usage(argv[0]);
179				break;
180			}
181		}
182		if (mode & SPI_LOOP) {
183			if (mode & SPI_TX_DUAL)
184				mode |= SPI_RX_DUAL;
185			if (mode & SPI_TX_QUAD)
186				mode |= SPI_RX_QUAD;
187		}
188	}
189	
190	int main(int argc, char *argv[])
191	{
192		int ret = 0;
193		int fd;
194	
195		parse_opts(argc, argv);
196	
197		fd = open(device, O_RDWR);
198		if (fd < 0)
199			pabort("can't open device");
200	
201		/*
202		 * spi mode
203		 */
204		ret = ioctl(fd, SPI_IOC_WR_MODE32, &mode);
205		if (ret == -1)
206			pabort("can't set spi mode");
207	
208		ret = ioctl(fd, SPI_IOC_RD_MODE32, &mode);
209		if (ret == -1)
210			pabort("can't get spi mode");
211	
212		/*
213		 * bits per word
214		 */
215		ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
216		if (ret == -1)
217			pabort("can't set bits per word");
218	
219		ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
220		if (ret == -1)
221			pabort("can't get bits per word");
222	
223		/*
224		 * max speed hz
225		 */
226		ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
227		if (ret == -1)
228			pabort("can't set max speed hz");
229	
230		ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
231		if (ret == -1)
232			pabort("can't get max speed hz");
233	
234		printf("spi mode: 0x%x\n", mode);
235		printf("bits per word: %d\n", bits);
236		printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);
237	
238		transfer(fd);
239	
240		close(fd);
241	
242		return ret;
243	}
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