summaryrefslogtreecommitdiffstats
path: root/kernel/Documentation/spi/spidev_test.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/Documentation/spi/spidev_test.c')
-rw-r--r--kernel/Documentation/spi/spidev_test.c318
1 files changed, 318 insertions, 0 deletions
diff --git a/kernel/Documentation/spi/spidev_test.c b/kernel/Documentation/spi/spidev_test.c
new file mode 100644
index 000000000..135b3f592
--- /dev/null
+++ b/kernel/Documentation/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;
+}