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Based on kernel version 3.13. Page generated on 2014-01-20 22:04 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 uint8_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		ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
61		if (ret < 1)
62			pabort("can't send spi message");
63	
64		for (ret = 0; ret < ARRAY_SIZE(tx); ret++) {
65			if (!(ret % 6))
66				puts("");
67			printf("%.2X ", rx[ret]);
68		}
69		puts("");
70	}
71	
72	static void print_usage(const char *prog)
73	{
74		printf("Usage: %s [-DsbdlHOLC3]\n", prog);
75		puts("  -D --device   device to use (default /dev/spidev1.1)\n"
76		     "  -s --speed    max speed (Hz)\n"
77		     "  -d --delay    delay (usec)\n"
78		     "  -b --bpw      bits per word \n"
79		     "  -l --loop     loopback\n"
80		     "  -H --cpha     clock phase\n"
81		     "  -O --cpol     clock polarity\n"
82		     "  -L --lsb      least significant bit first\n"
83		     "  -C --cs-high  chip select active high\n"
84		     "  -3 --3wire    SI/SO signals shared\n");
85		exit(1);
86	}
87	
88	static void parse_opts(int argc, char *argv[])
89	{
90		while (1) {
91			static const struct option lopts[] = {
92				{ "device",  1, 0, 'D' },
93				{ "speed",   1, 0, 's' },
94				{ "delay",   1, 0, 'd' },
95				{ "bpw",     1, 0, 'b' },
96				{ "loop",    0, 0, 'l' },
97				{ "cpha",    0, 0, 'H' },
98				{ "cpol",    0, 0, 'O' },
99				{ "lsb",     0, 0, 'L' },
100				{ "cs-high", 0, 0, 'C' },
101				{ "3wire",   0, 0, '3' },
102				{ "no-cs",   0, 0, 'N' },
103				{ "ready",   0, 0, 'R' },
104				{ NULL, 0, 0, 0 },
105			};
106			int c;
107	
108			c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR", lopts, NULL);
109	
110			if (c == -1)
111				break;
112	
113			switch (c) {
114			case 'D':
115				device = optarg;
116				break;
117			case 's':
118				speed = atoi(optarg);
119				break;
120			case 'd':
121				delay = atoi(optarg);
122				break;
123			case 'b':
124				bits = atoi(optarg);
125				break;
126			case 'l':
127				mode |= SPI_LOOP;
128				break;
129			case 'H':
130				mode |= SPI_CPHA;
131				break;
132			case 'O':
133				mode |= SPI_CPOL;
134				break;
135			case 'L':
136				mode |= SPI_LSB_FIRST;
137				break;
138			case 'C':
139				mode |= SPI_CS_HIGH;
140				break;
141			case '3':
142				mode |= SPI_3WIRE;
143				break;
144			case 'N':
145				mode |= SPI_NO_CS;
146				break;
147			case 'R':
148				mode |= SPI_READY;
149				break;
150			default:
151				print_usage(argv[0]);
152				break;
153			}
154		}
155	}
156	
157	int main(int argc, char *argv[])
158	{
159		int ret = 0;
160		int fd;
161	
162		parse_opts(argc, argv);
163	
164		fd = open(device, O_RDWR);
165		if (fd < 0)
166			pabort("can't open device");
167	
168		/*
169		 * spi mode
170		 */
171		ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
172		if (ret == -1)
173			pabort("can't set spi mode");
174	
175		ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
176		if (ret == -1)
177			pabort("can't get spi mode");
178	
179		/*
180		 * bits per word
181		 */
182		ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
183		if (ret == -1)
184			pabort("can't set bits per word");
185	
186		ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
187		if (ret == -1)
188			pabort("can't get bits per word");
189	
190		/*
191		 * max speed hz
192		 */
193		ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
194		if (ret == -1)
195			pabort("can't set max speed hz");
196	
197		ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
198		if (ret == -1)
199			pabort("can't get max speed hz");
200	
201		printf("spi mode: %d\n", mode);
202		printf("bits per word: %d\n", bits);
203		printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);
204	
205		transfer(fd);
206	
207		close(fd);
208	
209		return ret;
210	}
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