// 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 <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)
  {
  	perror(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 */

  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,
  };
  
  uint8_t default_rx[ARRAY_SIZE(default_tx)] = {0, };
  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("|
  ");

  			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_QUAD)
  		tr.tx_nbits = 4;
  	else if (mode & SPI_TX_DUAL)
  		tr.tx_nbits = 2;
  	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_QUAD | SPI_TX_DUAL))
  			tr.rx_buf = 0;
  		else if (mode & (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]
  ", prog);

  	puts("  -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
  ");

  	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' },

  			{ "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:lHOLC3NR24p: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 'S':
  			transfer_size = atoi(optarg);
  			break;
  		case 'I':
  			iterations = atoi(optarg);
  			break;

  		default:
  			print_usage(argv[0]);
  			break;
  		}
  	}

  	if (mode & SPI_LOOP) {
  		if (mode & SPI_TX_DUAL)
  			mode |= SPI_RX_DUAL;
  		if (mode & SPI_TX_QUAD)
  			mode |= SPI_RX_QUAD;
  	}

  }

  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
  ", 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 !
  ");
  			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);
  
  	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
  ", mode);

  	printf("bits per word: %d
  ", bits);
  	printf("max speed: %d Hz (%d KHz)
  ", speed, speed/1000);

  	if (input_tx && input_file)
  		pabort("only one of -p and --input may be selected");

  	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
  ",
  		       _write_count/1024.0, _read_count/1024.0);
  	} else

  		transfer(fd, default_tx, default_rx, sizeof(default_tx));

  
  	close(fd);
  
  	return ret;
  }