[PATCH 3/3] commands: add i2c commands

Eric Bénard eric at eukrea.com
Tue May 18 05:26:48 EDT 2010


theses commands allow low level access to i2c bus and can be useful
to setup an i2c device without having to add code, compile and flash
barebox.

Signed-off-by: Eric Bénard <eric at eukrea.com>
---
 commands/Kconfig  |    8 ++
 commands/Makefile |    1 +
 commands/i2c.c    |  233 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 242 insertions(+), 0 deletions(-)
 create mode 100644 commands/i2c.c

diff --git a/commands/Kconfig b/commands/Kconfig
index 0c09f91..7115b18 100644
--- a/commands/Kconfig
+++ b/commands/Kconfig
@@ -314,4 +314,12 @@ config CMD_UNLZO
 	  Say yes here to get the unlzo command. lzo is a fast compression
 	  algorithm by Markus Franz Xaver Johannes Oberhumer.
 
+config CMD_I2C
+	bool
+	depends on DRIVER_I2C_I2CDEV
+	prompt "i2c commands"
+	help
+	  include i2c_probe, i2c_read and i2c_write commands to communicate
+	  on i2c bus.
+
 endmenu
diff --git a/commands/Makefile b/commands/Makefile
index 74b0994..3eef5de 100644
--- a/commands/Makefile
+++ b/commands/Makefile
@@ -48,3 +48,4 @@ obj-$(CONFIG_CMD_BMP)		+= bmp.o
 obj-$(CONFIG_USB_GADGET_DFU)	+= dfu.o
 obj-$(CONFIG_CMD_GPIO)		+= gpio.o
 obj-$(CONFIG_CMD_UNLZO)		+= unlzo.o
+obj-$(CONFIG_CMD_I2C)		+= i2c.o
diff --git a/commands/i2c.c b/commands/i2c.c
new file mode 100644
index 0000000..b4152eb
--- /dev/null
+++ b/commands/i2c.c
@@ -0,0 +1,233 @@
+/*
+ * i2c.c - i2c commands
+ *
+ * Copyright (c) 2010 Eric Bénard <eric at eukrea.Com>, Eukréa Electromatique
+ *
+ * originals hex1_bin and hex2_bin are
+ * (C) Copyright 2000 Wolfgang Denk, DENX Software Engineering, wd at denx.de.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <command.h>
+#include <errno.h>
+#include <malloc.h>
+#include <getopt.h>
+#include <i2c/i2c.h>
+
+struct i2c_client	*client;
+extern struct i2c_client *i2cdev_get_client(void);
+
+static int hex1_bin(char c)
+{
+	if (c >= '0' && c <= '9')
+		return c - '0';
+	if (c >= 'a' && c <= 'f')
+		return c + 10 - 'a';
+	if (c >= 'A' && c <= 'F')
+		return c + 10 - 'A';
+	return -1;
+}
+
+static int hex2_bin(char *s)
+{
+	int i, j;
+
+	if (*s == '0' && (*(s+1) == 'x'))
+		s += 2;
+	i = hex1_bin(*s++);
+	if (i < 0)
+		return -1;
+	j = hex1_bin(*s);
+	if (j < 0)
+		return -1;
+	return (i<<4) + j;
+}
+
+static int do_i2c_probe(struct command *cmdtp, int argc, char *argv[])
+{
+	struct i2c_client *client;
+	int startaddr = -1, stopaddr = -1, addr, ret;
+	u8 reg;
+
+	if (argc < 3)
+		return COMMAND_ERROR_USAGE;
+
+	startaddr = hex2_bin(argv[1]);
+	stopaddr = hex2_bin(argv[2]);
+	if ((startaddr == -1) || (stopaddr == -1))
+		return COMMAND_ERROR_USAGE;
+
+	client = i2cdev_get_client();
+	if (!client)
+		return -ENODEV;
+
+	printf("probing i2c range 0X%02x - 0x%02x :\n", startaddr, stopaddr);
+	for (addr = startaddr; addr != stopaddr; addr++) {
+		client->addr = addr;
+		ret = i2c_write_reg(client, 0x00, &reg, 0);
+		if (ret == 0)
+			printf("0x%02x ", addr);
+	}
+	printf("\n");
+	return 0;
+}
+
+static const __maybe_unused char cmd_i2c_probe_help[] =
+"Usage: i2c_probe 0xstartaddr 0xstopaddr\n"
+"probe a range of i2c addresses.\n";
+
+BAREBOX_CMD_START(i2c_probe)
+	.cmd		= do_i2c_probe,
+	.usage		= "probe for an i2c device",
+	BAREBOX_CMD_HELP(cmd_i2c_probe_help)
+BAREBOX_CMD_END
+
+static int do_i2c_write(struct command *cmdtp, int argc, char *argv[])
+{
+	struct i2c_client *client;
+	int addr = -1, reg = -1, count = -1, ret, opt;
+	void *buf = NULL;
+
+	if (argc < 5)
+		return COMMAND_ERROR_USAGE;
+
+	while ((opt = getopt(argc, argv, "a:c:r:")) > 0) {
+		switch (opt) {
+		case 'a':
+			addr = hex2_bin(optarg);
+			if (addr < 0)
+				return COMMAND_ERROR_USAGE;
+			break;
+		case 'c':
+			count = simple_strtoul(optarg, NULL, 0);
+			break;
+		case 'r':
+			reg = hex2_bin(optarg);
+			if (reg < 0)
+				return COMMAND_ERROR_USAGE;
+			break;
+		}
+	}
+	if ((argc - optind) != count)
+		return COMMAND_ERROR_USAGE;
+
+	client = i2cdev_get_client();
+	if (!client)
+		return -ENODEV;
+	client->addr = addr;
+
+	buf = malloc(count);
+	if (buf) {
+		int i;
+		u8 tmp;
+		for (i = 0; i < count; i++) {
+			tmp = hex2_bin(argv[optind+i]);
+			if (tmp < 1) {
+				free(buf);
+				return COMMAND_ERROR_USAGE;
+			}
+			*(u8 *) (buf + i) = tmp;
+		}
+		ret = i2c_write_reg(client, reg, buf, count);
+		if (ret != count) {
+			free(buf);
+			return ret;
+		}
+		free(buf);
+		printf("wrote %i bytes starting at reg 0x%02x to i2cdev \
+			0x%02x\n", count, reg, addr);
+		return 0;
+	}
+	return 1;
+}
+
+static const __maybe_unused char cmd_i2c_write_help[] =
+"Usage: i2c_write [OPTION] ... hexdatas\n"
+"write to i2c device.\n"
+"  -a 0x<addr>   i2c device address\n"
+"  -r 0x<reg>    start register\n"
+"  -c <count>  byte number to write\n";
+
+BAREBOX_CMD_START(i2c_write)
+	.cmd		= do_i2c_write,
+	.usage		= "write to an i2c device",
+	BAREBOX_CMD_HELP(cmd_i2c_write_help)
+BAREBOX_CMD_END
+
+static int do_i2c_read(struct command *cmdtp, int argc, char *argv[])
+{
+	struct i2c_client *client;
+	void *buf = NULL;
+	int count = -1, addr = -1, reg = -1, ret, opt;
+
+	if (argc < 4)
+		return COMMAND_ERROR_USAGE;
+
+	while ((opt = getopt(argc, argv, "a:c:r:")) > 0) {
+		switch (opt) {
+		case 'a':
+			addr = hex2_bin(optarg);
+			if (addr < 0)
+				return COMMAND_ERROR_USAGE;
+			break;
+		case 'c':
+			count = simple_strtoul(optarg, NULL, 0);
+			break;
+		case 'r':
+			reg = hex2_bin(optarg);
+			if (reg < 0)
+				return COMMAND_ERROR_USAGE;
+			break;
+		}
+	}
+
+	client = i2cdev_get_client();
+	if (!client)
+		return -ENODEV;
+	client->addr = addr;
+
+	buf = malloc(count);
+	if (buf) {
+		ret = i2c_read_reg(client, reg, buf, count);
+		if (ret == count) {
+			int i;
+			printf("read %i bytes starting at reg 0x%02x from \
+				i2cdev 0x%02x\n", count, reg, addr);
+			for (i = 0; i < count; i++)
+				printf("0x%02x ", *(u8 *) (buf + i));
+			printf("\n");
+			free(buf);
+			return 0;
+		}
+		free(buf);
+	}
+	return 1;
+}
+
+static const __maybe_unused char cmd_i2c_read_help[] =
+"Usage: i2c_read [OPTION]\n"
+"read i2c device.\n"
+"  -a 0x<addr>   i2c device address\n"
+"  -r 0x<reg>    start register\n"
+"  -c <count>  byte count\n";
+
+BAREBOX_CMD_START(i2c_read)
+	.cmd		= do_i2c_read,
+	.usage		= "read from an i2c device",
+	BAREBOX_CMD_HELP(cmd_i2c_read_help)
+BAREBOX_CMD_END
-- 
1.6.3.3




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