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 uint32_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 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
87static 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
107static 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
190int 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}