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 <w...@the-dreams.de>
---

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 <w...@sang-engineering.com>
+    Copyright (C) 2015 Renesas Electronics Corporation
+
+    Based on i2cget.c:
+    Copyright (C) 2005-2012  Jean Delvare <jdelv...@suse.de>
+
+    which is based on i2cset.c:
+    Copyright (C) 2001-2003  Frodo Looijaard <fro...@dds.nl>, and
+                             Mark D. Studebaker <mdsxyz...@yahoo.com>
+    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-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to