tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
26static void pabort(const char *s)
27{
28 perror(s);
29 abort();
30}
31
32static const char *device = "/dev/spidev1.1";
33static uint8_t mode;
34static uint8_t bits = 8;
35static uint32_t speed = 500000;
36static uint16_t delay;
37
38static 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
72void 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
88void 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 { NULL, 0, 0, 0 },
103 };
104 int c;
105
106 c = getopt_long(argc, argv, "D:s:d:b:lHOLC3", lopts, NULL);
107
108 if (c == -1)
109 break;
110
111 switch (c) {
112 case 'D':
113 device = optarg;
114 break;
115 case 's':
116 speed = atoi(optarg);
117 break;
118 case 'd':
119 delay = atoi(optarg);
120 break;
121 case 'b':
122 bits = atoi(optarg);
123 break;
124 case 'l':
125 mode |= SPI_LOOP;
126 break;
127 case 'H':
128 mode |= SPI_CPHA;
129 break;
130 case 'O':
131 mode |= SPI_CPOL;
132 break;
133 case 'L':
134 mode |= SPI_LSB_FIRST;
135 break;
136 case 'C':
137 mode |= SPI_CS_HIGH;
138 break;
139 case '3':
140 mode |= SPI_3WIRE;
141 break;
142 default:
143 print_usage(argv[0]);
144 break;
145 }
146 }
147}
148
149int main(int argc, char *argv[])
150{
151 int ret = 0;
152 int fd;
153
154 parse_opts(argc, argv);
155
156 fd = open(device, O_RDWR);
157 if (fd < 0)
158 pabort("can't open device");
159
160 /*
161 * spi mode
162 */
163 ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
164 if (ret == -1)
165 pabort("can't set spi mode");
166
167 ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
168 if (ret == -1)
169 pabort("can't get spi mode");
170
171 /*
172 * bits per word
173 */
174 ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
175 if (ret == -1)
176 pabort("can't set bits per word");
177
178 ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
179 if (ret == -1)
180 pabort("can't get bits per word");
181
182 /*
183 * max speed hz
184 */
185 ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
186 if (ret == -1)
187 pabort("can't set max speed hz");
188
189 ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
190 if (ret == -1)
191 pabort("can't get max speed hz");
192
193 printf("spi mode: %d\n", mode);
194 printf("bits per word: %d\n", bits);
195 printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);
196
197 transfer(fd);
198
199 close(fd);
200
201 return ret;
202}