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 }
211
转自：http://tomoyo.sourceforge.jp/cgi-bin/lxr/source/Documentation/spi/spidev_test.c#L51
