Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  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 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 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                         { 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 
149 int 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 }
203 
  This page was automatically generated by the LXR engine.