linux驱动开发.之spi测试工具spidev_test源码（一）

同i2c-tools工具类似，spidev_test是用来测试SPI BUS的用户态程序，其源码存在kernel目录下的tools下，具体为tools\spi\spidev_test.c。buildroot同样也提供名为spidev_test的package，可以直接进行编译，方便用户调试spi总线。

一、spidev_test
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/plain/tools/spi/

二、spi-tools
https://github.com/cpb-/spi-tools

spidev_test.c开源代码

// SPDX-License-Identifier: GPL-2.0-only
/** SPI testing utility (using spidev driver)** Copyright (c) 2007  MontaVista Software, Inc.* Copyright (c) 2007  Anton Vorontsov <avorontsov@ru.mvista.com>** Cross-compile with cross-gcc -I/path/to/cross-kernel/include*/#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <getopt.h>
#include <fcntl.h>
#include <time.h>
#include <sys/ioctl.h>
#include <linux/ioctl.h>
#include <sys/stat.h>
#include <linux/types.h>
#include <linux/spi/spidev.h>#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))static void pabort(const char *s)
{if (errno != 0)perror(s);elseprintf("%s\n", s);abort();
}static const char *device = "/dev/spidev1.1";
static uint32_t mode;
static uint8_t bits = 8;
static char *input_file;
static char *output_file;
static uint32_t speed = 500000;
static uint16_t delay;
static int verbose;
static int transfer_size;
static int iterations;
static int interval = 5; /* interval in seconds for showing transfer rate */static uint8_t default_tx[] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0x40, 0x00, 0x00, 0x00, 0x00, 0x95,0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,0xF0, 0x0D,
};static uint8_t default_rx[ARRAY_SIZE(default_tx)] = {0, };
static char *input_tx;static void hex_dump(const void *src, size_t length, size_t line_size,char *prefix)
{int i = 0;const unsigned char *address = src;const unsigned char *line = address;unsigned char c;printf("%s | ", prefix);while (length-- > 0) {printf("%02X ", *address++);if (!(++i % line_size) || (length == 0 && i % line_size)) {if (length == 0) {while (i++ % line_size)printf("__ ");}printf(" |");while (line < address) {c = *line++;printf("%c", (c < 32 || c > 126) ? '.' : c);}printf("|\n");if (length > 0)printf("%s | ", prefix);}}
}/**  Unescape - process hexadecimal escape character*      converts shell input "\x23" -> 0x23*/
static int unescape(char *_dst, char *_src, size_t len)
{int ret = 0;int match;char *src = _src;char *dst = _dst;unsigned int ch;while (*src) {if (*src == '\\' && *(src+1) == 'x') {match = sscanf(src + 2, "%2x", &ch);if (!match)pabort("malformed input string");src += 4;*dst++ = (unsigned char)ch;} else {*dst++ = *src++;}ret++;}return ret;
}static void transfer(int fd, uint8_t const *tx, uint8_t const *rx, size_t len)
{int ret;int out_fd;struct spi_ioc_transfer tr = {.tx_buf = (unsigned long)tx,.rx_buf = (unsigned long)rx,.len = len,.delay_usecs = delay,.speed_hz = speed,.bits_per_word = bits,};if (mode & SPI_TX_OCTAL)tr.tx_nbits = 8;else if (mode & SPI_TX_QUAD)tr.tx_nbits = 4;else if (mode & SPI_TX_DUAL)tr.tx_nbits = 2;if (mode & SPI_RX_OCTAL)tr.rx_nbits = 8;else if (mode & SPI_RX_QUAD)tr.rx_nbits = 4;else if (mode & SPI_RX_DUAL)tr.rx_nbits = 2;if (!(mode & SPI_LOOP)) {if (mode & (SPI_TX_OCTAL | SPI_TX_QUAD | SPI_TX_DUAL))tr.rx_buf = 0;else if (mode & (SPI_RX_OCTAL | SPI_RX_QUAD | SPI_RX_DUAL))tr.tx_buf = 0;}ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);if (ret < 1)pabort("can't send spi message");if (verbose)hex_dump(tx, len, 32, "TX");if (output_file) {out_fd = open(output_file, O_WRONLY | O_CREAT | O_TRUNC, 0666);if (out_fd < 0)pabort("could not open output file");ret = write(out_fd, rx, len);if (ret != len)pabort("not all bytes written to output file");close(out_fd);}if (verbose)hex_dump(rx, len, 32, "RX");
}static void print_usage(const char *prog)
{printf("Usage: %s [-DsbdlHOLC3vpNR24SI]\n", prog);puts("  -D --device   device to use (default /dev/spidev1.1)\n""  -s --speed    max speed (Hz)\n""  -d --delay    delay (usec)\n""  -b --bpw      bits per word\n""  -i --input    input data from a file (e.g. \"test.bin\")\n""  -o --output   output data to a file (e.g. \"results.bin\")\n""  -l --loop     loopback\n""  -H --cpha     clock phase\n""  -O --cpol     clock polarity\n""  -L --lsb      least significant bit first\n""  -C --cs-high  chip select active high\n""  -3 --3wire    SI/SO signals shared\n""  -v --verbose  Verbose (show tx buffer)\n""  -p            Send data (e.g. \"1234\\xde\\xad\")\n""  -N --no-cs    no chip select\n""  -R --ready    slave pulls low to pause\n""  -2 --dual     dual transfer\n""  -4 --quad     quad transfer\n""  -8 --octal    octal transfer\n""  -S --size     transfer size\n""  -I --iter     iterations\n");exit(1);
}static void parse_opts(int argc, char *argv[])
{while (1) {static const struct option lopts[] = {{ "device",  1, 0, 'D' },{ "speed",   1, 0, 's' },{ "delay",   1, 0, 'd' },{ "bpw",     1, 0, 'b' },{ "input",   1, 0, 'i' },{ "output",  1, 0, 'o' },{ "loop",    0, 0, 'l' },{ "cpha",    0, 0, 'H' },{ "cpol",    0, 0, 'O' },{ "lsb",     0, 0, 'L' },{ "cs-high", 0, 0, 'C' },{ "3wire",   0, 0, '3' },{ "no-cs",   0, 0, 'N' },{ "ready",   0, 0, 'R' },{ "dual",    0, 0, '2' },{ "verbose", 0, 0, 'v' },{ "quad",    0, 0, '4' },{ "octal",   0, 0, '8' },{ "size",    1, 0, 'S' },{ "iter",    1, 0, 'I' },{ NULL, 0, 0, 0 },};int c;c = getopt_long(argc, argv, "D:s:d:b:i:o:lHOLC3NR248p:vS:I:",lopts, NULL);if (c == -1)break;switch (c) {case 'D':device = optarg;break;case 's':speed = atoi(optarg);break;case 'd':delay = atoi(optarg);break;case 'b':bits = atoi(optarg);break;case 'i':input_file = optarg;break;case 'o':output_file = optarg;break;case 'l':mode |= SPI_LOOP;break;case 'H':mode |= SPI_CPHA;break;case 'O':mode |= SPI_CPOL;break;case 'L':mode |= SPI_LSB_FIRST;break;case 'C':mode |= SPI_CS_HIGH;break;case '3':mode |= SPI_3WIRE;break;case 'N':mode |= SPI_NO_CS;break;case 'v':verbose = 1;break;case 'R':mode |= SPI_READY;break;case 'p':input_tx = optarg;break;case '2':mode |= SPI_TX_DUAL;break;case '4':mode |= SPI_TX_QUAD;break;case '8':mode |= SPI_TX_OCTAL;break;case 'S':transfer_size = atoi(optarg);break;case 'I':iterations = atoi(optarg);break;default:print_usage(argv[0]);}}if (mode & SPI_LOOP) {if (mode & SPI_TX_DUAL)mode |= SPI_RX_DUAL;if (mode & SPI_TX_QUAD)mode |= SPI_RX_QUAD;if (mode & SPI_TX_OCTAL)mode |= SPI_RX_OCTAL;}
}static void transfer_escaped_string(int fd, char *str)
{size_t size = strlen(str);uint8_t *tx;uint8_t *rx;tx = malloc(size);if (!tx)pabort("can't allocate tx buffer");rx = malloc(size);if (!rx)pabort("can't allocate rx buffer");size = unescape((char *)tx, str, size);transfer(fd, tx, rx, size);free(rx);free(tx);
}static void transfer_file(int fd, char *filename)
{ssize_t bytes;struct stat sb;int tx_fd;uint8_t *tx;uint8_t *rx;if (stat(filename, &sb) == -1)pabort("can't stat input file");tx_fd = open(filename, O_RDONLY);if (tx_fd < 0)pabort("can't open input file");tx = malloc(sb.st_size);if (!tx)pabort("can't allocate tx buffer");rx = malloc(sb.st_size);if (!rx)pabort("can't allocate rx buffer");bytes = read(tx_fd, tx, sb.st_size);if (bytes != sb.st_size)pabort("failed to read input file");transfer(fd, tx, rx, sb.st_size);free(rx);free(tx);close(tx_fd);
}static uint64_t _read_count;
static uint64_t _write_count;static void show_transfer_rate(void)
{static uint64_t prev_read_count, prev_write_count;double rx_rate, tx_rate;rx_rate = ((_read_count - prev_read_count) * 8) / (interval*1000.0);tx_rate = ((_write_count - prev_write_count) * 8) / (interval*1000.0);printf("rate: tx %.1fkbps, rx %.1fkbps\n", rx_rate, tx_rate);prev_read_count = _read_count;prev_write_count = _write_count;
}static void transfer_buf(int fd, int len)
{uint8_t *tx;uint8_t *rx;int i;tx = malloc(len);if (!tx)pabort("can't allocate tx buffer");for (i = 0; i < len; i++)tx[i] = random();rx = malloc(len);if (!rx)pabort("can't allocate rx buffer");transfer(fd, tx, rx, len);_write_count += len;_read_count += len;if (mode & SPI_LOOP) {if (memcmp(tx, rx, len)) {fprintf(stderr, "transfer error !\n");hex_dump(tx, len, 32, "TX");hex_dump(rx, len, 32, "RX");exit(1);}}free(rx);free(tx);
}int main(int argc, char *argv[])
{int ret = 0;int fd;parse_opts(argc, argv);if (input_tx && input_file)pabort("only one of -p and --input may be selected");fd = open(device, O_RDWR);if (fd < 0)pabort("can't open device");/** spi mode*/ret = ioctl(fd, SPI_IOC_WR_MODE32, &mode);if (ret == -1)pabort("can't set spi mode");ret = ioctl(fd, SPI_IOC_RD_MODE32, &mode);if (ret == -1)pabort("can't get spi mode");/** bits per word*/ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);if (ret == -1)pabort("can't set bits per word");ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);if (ret == -1)pabort("can't get bits per word");/** max speed hz*/ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);if (ret == -1)pabort("can't set max speed hz");ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);if (ret == -1)pabort("can't get max speed hz");printf("spi mode: 0x%x\n", mode);printf("bits per word: %u\n", bits);printf("max speed: %u Hz (%u kHz)\n", speed, speed/1000);if (input_tx)transfer_escaped_string(fd, input_tx);else if (input_file)transfer_file(fd, input_file);else if (transfer_size) {struct timespec last_stat;clock_gettime(CLOCK_MONOTONIC, &last_stat);while (iterations-- > 0) {struct timespec current;transfer_buf(fd, transfer_size);clock_gettime(CLOCK_MONOTONIC, &current);if (current.tv_sec - last_stat.tv_sec > interval) {show_transfer_rate();last_stat = current;}}printf("total: tx %.1fKB, rx %.1fKB\n",_write_count/1024.0, _read_count/1024.0);} elsetransfer(fd, default_tx, default_rx, sizeof(default_tx));close(fd);return ret;
}

https://blog.csdn.net/qq_41495871/article/details/100584284

https://www.cnblogs.com/sankye/p/3955630.html

https://blog.csdn.net/weixin_40407893/article/details/102461906?spm=1001.2101.3001.6650.2&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-2-102461906-blog-132819200.235%5Ev38%5Epc_relevant_anti_vip&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7ERate-2-102461906-blog-132819200.235%5Ev38%5Epc_relevant_anti_vip&utm_relevant_index=5

spidev_fdx.c

// SPDX-License-Identifier: GPL-2.0
#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 = (unsigned long)buf;xfer[0].len = 1;xfer[1].rx_buf = (unsigned long) 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	lsb, bits;__u32	mode, speed;if (ioctl(fd, SPI_IOC_RD_MODE32, &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 0x%x, %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;
}

2、编译成可执行文件后测试

spidev_test

Usage: spidev_test [-DsbdlHOLC3vpNR24SI]-D --device   device to use (default /dev/spidev1.1)-s --speed    max speed (Hz)-d --delay    delay (usec)-b --bpw      bits per word-i --input    input data from a file (e.g. "test.bin")-o --output   output data to a file (e.g. "results.bin")-l --loop     loopback-H --cpha     clock phase-O --cpol     clock polarity-L --lsb      least significant bit first-C --cs-high  chip select active high-3 --3wire    SI/SO signals shared-v --verbose  Verbose (show tx buffer)-p            Send data (e.g. "1234\xde\xad")-N --no-cs    no chip select-R --ready    slave pulls low to pause-2 --dual     dual transfer-4 --quad     quad transfer-S --size     transfer size-I --iter     iterations

spidev_test -D /dev/spidev1.0 -s 5000 -p "\x48\x00\x00\x00" -vspi mode: 0x0
bits per word: 8
max speed: 5000 Hz (5 KHz)
TX | 48 00 00 00 __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __  | H...
RX | 00 00 00 00 __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __  | ....

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