2 * SPI testing utility (using spidev driver)
4 * Copyright (c) 2007 MontaVista Software, Inc.
5 * Copyright (c) 2007 Anton Vorontsov <avorontsov@ru.mvista.com>
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.
11 * Cross-compile with cross-gcc -I/path/to/cross-kernel/include
20 #include <sys/ioctl.h>
21 #include <linux/types.h>
22 #include <linux/spi/spidev.h>
24 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
26 static void pabort(const char *s)
32 static const char *device = "/dev/spidev1.1";
34 static uint8_t bits = 8;
35 static uint32_t speed = 500000;
36 static uint16_t delay;
38 static void transfer(int fd)
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,
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),
57 .bits_per_word = bits,
60 ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
62 pabort("can't send spi message");
64 for (ret = 0; ret < ARRAY_SIZE(tx); ret++) {
67 printf("%.2X ", rx[ret]);
72 static void print_usage(const char *prog)
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");
88 static void parse_opts(int argc, char *argv[])
91 static const struct option lopts[] = {
92 { "device", 1, 0, 'D' },
93 { "speed", 1, 0, 's' },
94 { "delay", 1, 0, 'd' },
96 { "loop", 0, 0, 'l' },
97 { "cpha", 0, 0, 'H' },
98 { "cpol", 0, 0, 'O' },
100 { "cs-high", 0, 0, 'C' },
101 { "3wire", 0, 0, '3' },
102 { "no-cs", 0, 0, 'N' },
103 { "ready", 0, 0, 'R' },
108 c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR", lopts, NULL);
118 speed = atoi(optarg);
121 delay = atoi(optarg);
136 mode |= SPI_LSB_FIRST;
151 print_usage(argv[0]);
157 int main(int argc, char *argv[])
162 parse_opts(argc, argv);
164 fd = open(device, O_RDWR);
166 pabort("can't open device");
171 ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
173 pabort("can't set spi mode");
175 ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
177 pabort("can't get spi mode");
182 ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
184 pabort("can't set bits per word");
186 ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
188 pabort("can't get bits per word");
193 ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
195 pabort("can't set max speed hz");
197 ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
199 pabort("can't get max speed hz");
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);