1 // SPDX-License-Identifier: GPL-2.0 2 #include <stdio.h> 3 #include <unistd.h> 4 #include <stdlib.h> 5 #include <fcntl.h> 6 #include <string.h> 7 8 #include <sys/ioctl.h> 9 #include <sys/types.h> 10 #include <sys/stat.h> 11 12 #include <linux/types.h> 13 #include <linux/spi/spidev.h> 14 15 16 static int verbose; 17 18 static void do_read(int fd, int len) 19 { 20 unsigned char buf[32], *bp; 21 int status; 22 23 /* read at least 2 bytes, no more than 32 */ 24 if (len < 2) 25 len = 2; 26 else if (len > sizeof(buf)) 27 len = sizeof(buf); 28 memset(buf, 0, sizeof buf); 29 30 status = read(fd, buf, len); 31 if (status < 0) { 32 perror("read"); 33 return; 34 } 35 if (status != len) { 36 fprintf(stderr, "short read\n"); 37 return; 38 } 39 40 printf("read(%2d, %2d): %02x %02x,", len, status, 41 buf[0], buf[1]); 42 status -= 2; 43 bp = buf + 2; 44 while (status-- > 0) 45 printf(" %02x", *bp++); 46 printf("\n"); 47 } 48 49 static void do_msg(int fd, int len) 50 { 51 struct spi_ioc_transfer xfer[2]; 52 unsigned char buf[32], *bp; 53 int status; 54 55 memset(xfer, 0, sizeof xfer); 56 memset(buf, 0, sizeof buf); 57 58 if (len > sizeof buf) 59 len = sizeof buf; 60 61 buf[0] = 0xaa; 62 xfer[0].tx_buf = (unsigned long)buf; 63 xfer[0].len = 1; 64 65 xfer[1].rx_buf = (unsigned long) buf; 66 xfer[1].len = len; 67 68 status = ioctl(fd, SPI_IOC_MESSAGE(2), xfer); 69 if (status < 0) { 70 perror("SPI_IOC_MESSAGE"); 71 return; 72 } 73 74 printf("response(%2d, %2d): ", len, status); 75 for (bp = buf; len; len--) 76 printf(" %02x", *bp++); 77 printf("\n"); 78 } 79 80 static void dumpstat(const char *name, int fd) 81 { 82 __u8 lsb, bits; 83 __u32 mode, speed; 84 85 if (ioctl(fd, SPI_IOC_RD_MODE32, &mode) < 0) { 86 perror("SPI rd_mode"); 87 return; 88 } 89 if (ioctl(fd, SPI_IOC_RD_LSB_FIRST, &lsb) < 0) { 90 perror("SPI rd_lsb_fist"); 91 return; 92 } 93 if (ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits) < 0) { 94 perror("SPI bits_per_word"); 95 return; 96 } 97 if (ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed) < 0) { 98 perror("SPI max_speed_hz"); 99 return; 100 } 101 102 printf("%s: spi mode 0x%x, %d bits %sper word, %d Hz max\n", 103 name, mode, bits, lsb ? "(lsb first) " : "", speed); 104 } 105 106 int main(int argc, char **argv) 107 { 108 int c; 109 int readcount = 0; 110 int msglen = 0; 111 int fd; 112 const char *name; 113 114 while ((c = getopt(argc, argv, "hm:r:v")) != EOF) { 115 switch (c) { 116 case 'm': 117 msglen = atoi(optarg); 118 if (msglen < 0) 119 goto usage; 120 continue; 121 case 'r': 122 readcount = atoi(optarg); 123 if (readcount < 0) 124 goto usage; 125 continue; 126 case 'v': 127 verbose++; 128 continue; 129 case 'h': 130 case '?': 131 usage: 132 fprintf(stderr, 133 "usage: %s [-h] [-m N] [-r N] /dev/spidevB.D\n", 134 argv[0]); 135 return 1; 136 } 137 } 138 139 if ((optind + 1) != argc) 140 goto usage; 141 name = argv[optind]; 142 143 fd = open(name, O_RDWR); 144 if (fd < 0) { 145 perror("open"); 146 return 1; 147 } 148 149 dumpstat(name, fd); 150 151 if (msglen) 152 do_msg(fd, msglen); 153 154 if (readcount) 155 do_read(fd, readcount); 156 157 close(fd); 158 return 0; 159 } 160