#include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <fcntl.h> #include <string.h> #include <sys/ioctl.h> #include <sys/types.h> #include <sys/stat.h> #include <linux/types.h> #include <linux/spi/spidev.h> static int verbose; static void do_read(int fd, int len) { unsigned char buf[32], *bp; int status; /* read at least 2 bytes, no more than 32 */ if (len < 2) len = 2; else if (len > sizeof(buf)) len = sizeof(buf); memset(buf, 0, sizeof buf); status = read(fd, buf, len); if (status < 0) { perror("read"); return; } if (status != len) { fprintf(stderr, "short read\n"); return; } printf("read(%2d, %2d): %02x %02x,", len, status, buf[0], buf[1]); status -= 2; bp = buf + 2; while (status-- > 0) printf(" %02x", *bp++); printf("\n"); } static void do_msg(int fd, int len) { struct spi_ioc_transfer xfer[2]; unsigned char buf[32], *bp; int status; memset(xfer, 0, sizeof xfer); memset(buf, 0, sizeof buf); if (len > sizeof buf) len = sizeof buf; buf[0] = 0xaa; xfer[0].tx_buf = (__u64) buf; xfer[0].len = 1; xfer[1].rx_buf = (__u64) buf; xfer[1].len = len; status = ioctl(fd, SPI_IOC_MESSAGE(2), xfer); if (status < 0) { perror("SPI_IOC_MESSAGE"); return; } printf("response(%2d, %2d): ", len, status); for (bp = buf; len; len--) printf(" %02x", *bp++); printf("\n"); } static void dumpstat(const char *name, int fd) { __u8 mode, lsb, bits; __u32 speed; if (ioctl(fd, SPI_IOC_RD_MODE, &mode) < 0) { perror("SPI rd_mode"); return; } if (ioctl(fd, SPI_IOC_RD_LSB_FIRST, &lsb) < 0) { perror("SPI rd_lsb_fist"); return; } if (ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits) < 0) { perror("SPI bits_per_word"); return; } if (ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed) < 0) { perror("SPI max_speed_hz"); return; } printf("%s: spi mode %d, %d bits %sper word, %d Hz max\n", name, mode, bits, lsb ? "(lsb first) " : "", speed); } int main(int argc, char **argv) { int c; int readcount = 0; int msglen = 0; int fd; const char *name; while ((c = getopt(argc, argv, "hm:r:v")) != EOF) { switch (c) { case 'm': msglen = atoi(optarg); if (msglen < 0) goto usage; continue; case 'r': readcount = atoi(optarg); if (readcount < 0) goto usage; continue; case 'v': verbose++; continue; case 'h': case '?': usage: fprintf(stderr, "usage: %s [-h] [-m N] [-r N] /dev/spidevB.D\n", argv[0]); return 1; } } if ((optind + 1) != argc) goto usage; name = argv[optind]; fd = open(name, O_RDWR); if (fd < 0) { perror("open"); return 1; } dumpstat(name, fd); if (msglen) do_msg(fd, msglen); if (readcount) do_read(fd, readcount); close(fd); return 0; }