This tool allows to construct and concat multiple I2C messages into one
single transfer. Its aim is to test I2C master controllers, and so there
is no SMBus fallback.
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxxxxx>
---
I've been missing such a tool a number of times now, so I finally got around to
writing it myself. As with all I2C tools, it can be dangerous, but it can also
be very useful when developing. I am not sure if distros should supply it, I'll
leave that to Jean's experience. For embedded build systems, I think this
should be selectable. It is RFC for now because it needs broader testing and some
more beautification. However, I've been using it already to test the i2c_quirk
infrastructure and Renesas I2C controllers.
tools/Module.mk | 8 +-
tools/i2ctransfer.c | 296 ++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 303 insertions(+), 1 deletion(-)
create mode 100644 tools/i2ctransfer.c
diff --git a/tools/Module.mk b/tools/Module.mk
index d14bb0c..62f1238 100644
--- a/tools/Module.mk
+++ b/tools/Module.mk
@@ -14,7 +14,7 @@ TOOLS_CFLAGS := -Wstrict-prototypes -Wshadow -Wpointer-arith -Wcast-qual \
-W -Wundef -Wmissing-prototypes -Iinclude
TOOLS_LDFLAGS := -Llib -li2c
-TOOLS_TARGETS := i2cdetect i2cdump i2cset i2cget
+TOOLS_TARGETS := i2cdetect i2cdump i2cset i2cget i2ctransfer
#
# Programs
@@ -32,6 +32,9 @@ $(TOOLS_DIR)/i2cset: $(TOOLS_DIR)/i2cset.o $(TOOLS_DIR)/i2cbusses.o $(TOOLS_DIR)
$(TOOLS_DIR)/i2cget: $(TOOLS_DIR)/i2cget.o $(TOOLS_DIR)/i2cbusses.o $(TOOLS_DIR)/util.o
$(CC) $(LDFLAGS) -o $@ $^ $(TOOLS_LDFLAGS)
+$(TOOLS_DIR)/i2ctransfer: $(TOOLS_DIR)/i2ctransfer.o $(TOOLS_DIR)/i2cbusses.o $(TOOLS_DIR)/util.o
+ $(CC) $(LDFLAGS) -o $@ $^ $(TOOLS_LDFLAGS)
+
#
# Objects
#
@@ -48,6 +51,9 @@ $(TOOLS_DIR)/i2cset.o: $(TOOLS_DIR)/i2cset.c $(TOOLS_DIR)/i2cbusses.h $(TOOLS_DI
$(TOOLS_DIR)/i2cget.o: $(TOOLS_DIR)/i2cget.c $(TOOLS_DIR)/i2cbusses.h $(TOOLS_DIR)/util.h version.h $(INCLUDE_DIR)/i2c/smbus.h
$(CC) $(CFLAGS) $(TOOLS_CFLAGS) -c $< -o $@
+$(TOOLS_DIR)/i2ctransfer.o: $(TOOLS_DIR)/i2ctransfer.c $(TOOLS_DIR)/i2cbusses.h $(TOOLS_DIR)/util.h version.h
+ $(CC) $(CFLAGS) -Wno-maybe-uninitialized $(TOOLS_CFLAGS) -c $< -o $@
+
$(TOOLS_DIR)/i2cbusses.o: $(TOOLS_DIR)/i2cbusses.c $(TOOLS_DIR)/i2cbusses.h
$(CC) $(CFLAGS) $(TOOLS_CFLAGS) -c $< -o $@
diff --git a/tools/i2ctransfer.c b/tools/i2ctransfer.c
new file mode 100644
index 0000000..30923f5
--- /dev/null
+++ b/tools/i2ctransfer.c
@@ -0,0 +1,296 @@
+/*
+ i2ctransfer.c - A user-space program to send concatenated i2c messages
+ Copyright (C) 2015 Wolfram Sang <wsa@xxxxxxxxxxxxxxxxxxxx>
+ Copyright (C) 2015 Renesas Electronics Corporation
+
+ Based on i2cget.c:
+ Copyright (C) 2005-2012 Jean Delvare <jdelvare@xxxxxxx>
+
+ which is based on i2cset.c:
+ Copyright (C) 2001-2003 Frodo Looijaard <frodol@xxxxxx>, and
+ Mark D. Studebaker <mdsxyz123@xxxxxxxxx>
+ Copyright (C) 2004-2005 Jean Delvare
+
+ 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, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+*/
+
+#include <sys/ioctl.h>
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <linux/i2c.h>
+#include <linux/i2c-dev.h>
+#include "i2cbusses.h"
+#include "util.h"
+#include "../version.h"
+
+enum parse_state {
+ PARSE_GET_ADDR,
+ PARSE_GET_FLAGS,
+ PARSE_GET_LENGTH,
+ PARSE_GET_DATA
+};
+
+#define PRINT_STDERR (1 << 0)
+#define PRINT_READ_BUF (1 << 1)
+#define PRINT_WRITE_BUF (1 << 2)
+#define PRINT_HEADER (1 << 3)
+
+static void help(void)
+{
+ fprintf(stderr,
+ "Usage: i2ctransfer [-f] [-y] [-v] [-V] I2CBUS ADDRESS FLAGS LENGTH [DATA]...\n"
+ " I2CBUS is an integer or an I2C bus name\n"
+ " ADDRESS is an integer (0x03 - 0x77)\n"
+ " FLAGS is one of:\n"
+ " r (read)\n"
+ " w (write)\n"
+ " LENGTH is an integer (0 - 65535)\n"
+ " DATA are LENGTH bytes, for a write message. They can be shortened by a suffix:\n"
+ " = (keep value constant until LENGTH)\n"
+ " + (increase value by 1 until LENGTH)\n"
+ " - (decrease value by 1 until LENGTH)\n"
+ "\nExample (on bus 0, write 0xbd to 0xc0-0xcf of device 0x50, read a byte from device 0x51):\n"
+ " # i2ctransfer 0 0x50 w 0x11 0xc0 0xbd= 0x51 r 1\n"
+ );
+}
+
+static int check_funcs(int file)
+{
+ unsigned long funcs;
+
+ /* check adapter functionality */
+ if (ioctl(file, I2C_FUNCS, &funcs) < 0) {
+ fprintf(stderr, "Error: Could not get the adapter "
+ "functionality matrix: %s\n", strerror(errno));
+ return -1;
+ }
+
+ if (!(funcs & I2C_FUNC_I2C)) {
+ fprintf(stderr, MISSING_FUNC_FMT, "I2C transfers");
+ return -1;
+ }
+
+ return 0;
+}
+
+static void print_msgs(struct i2c_msg *msgs, __u32 nmsgs, unsigned flags)
+{
+ __u32 i, j;
+ FILE *output = flags & PRINT_STDERR ? stderr : stdout;
+
+ for (i = 0; i < nmsgs; i++) {
+ int read = !!(msgs[i].flags & I2C_M_RD);
+ int newline = !!(flags & PRINT_HEADER);
+
+ if (flags & PRINT_HEADER)
+ fprintf(output, "Msg %u: addr 0x%04x, %s, len %u",
+ i, msgs[i].addr, read ? "read" : "write", msgs[i].len);
+ if (read == !!(flags & PRINT_READ_BUF) ||
+ !read == !!(flags & PRINT_WRITE_BUF)) {
+ if (flags & PRINT_HEADER)
+ fprintf(output, ", buf ");
+ for (j = 0; j < msgs[i].len; j++)
+ fprintf(output, "0x%02x ", msgs[i].buf[j]);
+ newline = 1;
+ }
+ if (newline)
+ fprintf(output, "\n");
+ }
+}
+
+static int confirm(const char *filename, struct i2c_msg *msgs, __u32 nmsgs)
+{
+ fprintf(stderr, "WARNING! This program can confuse your I2C bus, cause data loss and worse!\n");
+ fprintf(stderr, "I will send the following messages to device file %s:\n", filename);
+ print_msgs(msgs, nmsgs, PRINT_STDERR | PRINT_HEADER | PRINT_WRITE_BUF);
+
+ fprintf(stderr, "Continue? [y/N] ");
+ fflush(stderr);
+ if (!user_ack(0)) {
+ fprintf(stderr, "Aborting on user request.\n");
+ return 0;
+ }
+
+ return 1;
+}
+
+int main(int argc, char *argv[])
+{
+ char c, filename[20];
+ char *end;
+ int i2cbus, address, file, arg_idx = 1;
+ int force = 0, yes = 0, version = 0, verbose = 0;
+ unsigned flag_idx = 0, buf_idx = 0, nmsgs = 0;
+ unsigned long len, raw_data;
+ __u8 data;
+ __u8 *buf;
+ __u16 flags;
+ struct i2c_msg msgs[I2C_RDRW_IOCTL_MAX_MSGS];
+ struct i2c_rdwr_ioctl_data rdwr;
+ enum parse_state state = PARSE_GET_ADDR;
+
+ /* handle (optional) arg_idx first */
+ while (arg_idx < argc && argv[arg_idx][0] == '-') {
+ switch (argv[arg_idx][1]) {
+ case 'V': version = 1; break;
+ case 'v': verbose = 1; break;
+ case 'f': force = 1; break;
+ case 'y': yes = 1; break;
+ default:
+ fprintf(stderr, "Error: Unsupported option "
+ "\"%s\"!\n", argv[arg_idx]);
+ help();
+ exit(1);
+ }
+ arg_idx++;
+ }
+
+ if (version) {
+ fprintf(stderr, "i2ctransfer version %s\n", VERSION);
+ exit(0);
+ }
+
+ if (arg_idx == argc) {
+ help();
+ exit(0);
+ }
+
+ i2cbus = lookup_i2c_bus(argv[arg_idx++]);
+ if (i2cbus < 0)
+ exit(1);
+
+ file = open_i2c_dev(i2cbus, filename, sizeof(filename), 0);
+ if (file < 0 || check_funcs(file))
+ exit(1);
+
+ while (arg_idx < argc) {
+ switch (state) {
+ case PARSE_GET_ADDR:
+ address = parse_i2c_address(argv[arg_idx++]);
+ if (address < 0)
+ exit(1);
+
+ if (!force && set_slave_addr(file, address, 0))
+ exit(1);
+
+ msgs[nmsgs].addr = address;
+ state = PARSE_GET_FLAGS;
+ break;
+
+ case PARSE_GET_FLAGS:
+ flag_idx = 0;
+ flags = 0;
+ while ((c = argv[arg_idx][flag_idx])) {
+ switch (c) {
+ case 'r': flags |= I2C_M_RD; break;
+ case 'w': flags &= ~I2C_M_RD; break;
+ default:
+ fprintf(stderr, "Error: Invalid flag '%c'!\n", c);
+ exit(1);
+ }
+ flag_idx++;
+ }
+ msgs[nmsgs].flags = flags;
+ arg_idx++;
+ state = PARSE_GET_LENGTH;
+ break;
+
+ case PARSE_GET_LENGTH:
+ len = strtoul(argv[arg_idx++], &end, 0);
+ if (*end || len > 65535) {
+ fprintf(stderr, "Error: Length invalid!\n");
+ exit(1);
+ }
+
+ msgs[nmsgs].len = len;
+
+ buf = malloc(len);
+ if (!buf) {
+ fprintf(stderr, "Error: No memory for buffer!\n");
+ exit(ENOMEM);
+ }
+ memset(buf, 0, len);
+ msgs[nmsgs].buf = buf;
+
+ if (flags & I2C_M_RD) {
+ nmsgs++;
+ state = PARSE_GET_ADDR;
+ } else {
+ buf_idx = 0;
+ state = PARSE_GET_DATA;
+ }
+
+ break;
+
+ case PARSE_GET_DATA:
+ raw_data = strtoul(argv[arg_idx++], &end, 0);
+ if (raw_data > 255) {
+ fprintf(stderr, "Error: Data byte '%lu' invalid!\n", raw_data);
+ exit(1);
+ }
+ data = raw_data;
+ buf[buf_idx++] = data;
+
+ c = *end;
+ if (c) {
+ for (; buf_idx < len; buf_idx++) {
+ switch (c) {
+ case '+': data++; break;
+ case '-': data--; break;
+ case '=': break;
+ default:
+ fprintf(stderr, "Error: Invalid data byte suffix '%c'!\n", c);
+ exit(1);
+ }
+
+ buf[buf_idx] = data;
+ }
+ }
+
+ if (buf_idx == len) {
+ nmsgs++;
+ state = PARSE_GET_ADDR;
+ }
+
+ break;
+ }
+ }
+
+ if (state != PARSE_GET_ADDR) {
+ fprintf(stderr, "Error: Incomplete message\n");
+ exit(1);
+ }
+
+ if (nmsgs == 0) {
+ help();
+ exit(0);
+ }
+
+ if (!yes && !confirm(filename, msgs, nmsgs))
+ exit(0);
+
+ rdwr.msgs = msgs;
+ rdwr.nmsgs = nmsgs;
+ if (ioctl(file, I2C_RDWR, &rdwr) < 0) {
+ fprintf(stderr, "Error: Sending messages failed: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ close(file);
+
+ print_msgs(msgs, nmsgs, PRINT_READ_BUF | (verbose ? PRINT_HEADER | PRINT_WRITE_BUF : 0));
+
+ /* let Linux free malloced memory on termination */
+ exit(0);
+}
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
