spi: Move spi code from Documentation to tools

Jon Corbet requested this code moved with the last changeset,
https://lkml.org/lkml/2015/3/1/144,
but the patch was not applied because it missed the Makefile.
Moved spidev_test, spidev_fdx and their Makefile infrastructure.

Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 318 insertions, 0 deletions

diff --git a/tools/spi/spidev_test.c b/tools/spi/spidev_test.c
new file mode 100644
index 0000000..135b3f5
--- /dev/null
+++ b/tools/spi/spidev_test.c
@@ -0,0 +1,318 @@
+/*
+ * SPI testing utility (using spidev driver)
+ *
+ * Copyright (c) 2007  MontaVista Software, Inc.
+ * Copyright (c) 2007  Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License.
+ *
+ * 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 <sys/ioctl.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 uint32_t speed = 500000;
+static uint16_t delay;
+static int verbose;
+
+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(" | ");  /* right close */
+			while (line < address) {
+				c = *line++;
+				printf("%c", (c < 33 || c == 255) ? 0x2E : 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;
+	char *src = _src;
+	char *dst = _dst;
+	unsigned int ch;
+
+	while (*src) {
+		if (*src == '\\' && *(src+1) == 'x') {
+			sscanf(src + 2, "%2x", &ch);
+			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;
+
+	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");
+	hex_dump(rx, len, 32, "RX");
+}
+
+static void print_usage(const char *prog)
+{
+	printf("Usage: %s [-DsbdlHOLC3]\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"
+	     "  -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");
+	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' },
+			{ "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' },
+			{ NULL, 0, 0, 0 },
+		};
+		int c;
+
+		c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR24p:v", 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 '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;
+		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;
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	int ret = 0;
+	int fd;
+	uint8_t *tx;
+	uint8_t *rx;
+	int size;
+
+	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\n", mode);
+	printf("bits per word: %d\n", bits);
+	printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);
+
+	if (input_tx) {
+		size = strlen(input_tx+1);
+		tx = malloc(size);
+		rx = malloc(size);
+		size = unescape((char *)tx, input_tx, size);
+		transfer(fd, tx, rx, size);
+		free(rx);
+		free(tx);
+	} else {
+		transfer(fd, default_tx, default_rx, sizeof(default_tx));
+	}
+
+	close(fd);
+
+	return ret;
+}