[PATCH 3/4] commands: add i2c commands
Sascha Hauer
s.hauer at pengutronix.de
Tue May 25 03:03:41 EDT 2010
On Mon, May 24, 2010 at 03:46:07PM +0200, Eric Bénard wrote:
> 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>
> ---
> v3 :
> enable brain and fix v2
> tested on iMX27
> v2 :
> updated as per Sascha's comments
>
> commands/Kconfig | 8 ++
> commands/Makefile | 1 +
> commands/i2c.c | 218 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 227 insertions(+), 0 deletions(-)
> create mode 100644 commands/i2c.c
>
> diff --git a/commands/Kconfig b/commands/Kconfig
> index 0c09f91..0ea32d9 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 I2C
> + 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..4bd7d85
> --- /dev/null
> +++ b/commands/i2c.c
> @@ -0,0 +1,218 @@
> +/*
> + * i2c.c - i2c commands
> + *
> + * Copyright (c) 2010 Eric Bénard <eric at eukrea.Com>, Eukréa Electromatique
> + *
> + * 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;
> +
> +static int do_i2c_probe(struct command *cmdtp, int argc, char *argv[])
> +{
> + struct i2c_adapter *adapter;
> + struct i2c_client client;
> + int startaddr = -1, stopaddr = -1, addr, ret;
> + u8 reg;
> +
> + if (argc < 4)
> + return COMMAND_ERROR_USAGE;
> +
> + adapter = i2c_get_adapter(simple_strtoul(argv[1], NULL, 0));
> + if (!adapter)
> + return -ENODEV;
> + client.adapter = adapter;
> +
> + startaddr = simple_strtol(argv[2], NULL, 16);
> + stopaddr = simple_strtol(argv[3], NULL, 16);
> + if ((startaddr == -1) || (stopaddr == -1) || (startaddr > stopaddr))
> + return COMMAND_ERROR_USAGE;
> +
> + if (stopaddr > 0x7F)
> + stopaddr = 0x7F;
> +
> + 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, ®, 0);
> + if (ret == 0)
> + printf("0x%02x ", addr);
> + }
> + printf("\n");
> + return 0;
> +}
> +
> +static const __maybe_unused char cmd_i2c_probe_help[] =
> +"Usage: i2c_probe bus 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_adapter *adapter = NULL;
> + struct i2c_client client;
> + int addr = -1, reg = -1, count = -1, verbose = 0, ret, opt;
> + u8 *buf;
> +
> + while ((opt = getopt(argc, argv, "a:b:r:v")) > 0) {
> + switch (opt) {
> + case 'a':
> + addr = simple_strtol(optarg, NULL, 16);
> + break;
> + case 'r':
> + reg = simple_strtol(optarg, NULL, 16);
Normally barebox interpretes all numbers as decimal unless prefixed with
0x. You should keep this except for the hexdata below.
> + break;
> + case 'b':
> + adapter = i2c_get_adapter(simple_strtoul(optarg, NULL, 0));
> + if (!adapter)
> + return -ENODEV;
> + client.adapter = adapter;
> + break;
> + case 'v':
> + verbose = 1;
> + break;
> + }
> + }
> +
> + count = argc - optind;
> +
> + if ((addr < 0) || (reg < 0) || (count == 0) || (addr > 0x7F))
> + return COMMAND_ERROR_USAGE;
> +
> + client.addr = addr;
> +
> + buf = malloc(count);
> + if (buf) {
> + int i;
> + u8 tmp;
> + for (i = 0; i < count; i++) {
> + tmp = (char) simple_strtol(argv[optind+i], NULL, 16);
> + if (tmp < 0) {
simple_strtol does not return an error and an u8 is never < 0 anyway.
You can remove this check.
> + free(buf);
> + return COMMAND_ERROR_USAGE;
> + }
> + *(buf + i) = tmp;
> + }
> + ret = i2c_write_reg(&client, reg, buf, count);
> + if (ret != count) {
> + free(buf);
> + return ret;
> + }
> + if (verbose) {
> + printf("wrote %i bytes starting at reg 0x%02x to i2cdev 0x%02x on bus %i\n",
> + count, reg, addr, adapter->nr);
> + for (i = 0; i < count; i++)
> + printf("0x%02x ", *(buf + i));
the memory_display display function seems useful here. I should add a
prototype for it.
> + printf("\n");
> + }
> + free(buf);
> + 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"
> +" -b <bus_num> i2c bus number\n"
> +" -r 0x<reg> start register\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_adapter *adapter = NULL;
> + struct i2c_client client;
> + u8 *buf;
> + int count = -1, addr = -1, reg = -1, verbose = 0, ret, opt;
> +
> + while ((opt = getopt(argc, argv, "a:b:c:r:v")) > 0) {
> + switch (opt) {
> + case 'a':
> + addr = simple_strtol(optarg, NULL, 16);
> + break;
> + case 'c':
> + count = simple_strtoul(optarg, NULL, 0);
> + break;
> + case 'b':
> + adapter = i2c_get_adapter(simple_strtoul(optarg, NULL, 0));
> + if (!adapter)
> + return -ENODEV;
> + client.adapter = adapter;
> + break;
> + case 'r':
> + reg = simple_strtol(optarg, NULL, 16);
> + break;
> + case 'v':
> + verbose = 1;
> + break;
> + }
> + }
> +
> + if ((addr < 0) || (reg < 0) || (count == 0) || (addr > 0x7F))
> + return COMMAND_ERROR_USAGE;
> +
> + client.addr = addr;
> +
> + buf = malloc(count);
> + if (buf) {
> + ret = i2c_read_reg(&client, reg, buf, count);
> + if (ret == count) {
> + int i;
> + if (verbose)
> + printf("read %i bytes starting at reg 0x%02x from i2cdev 0x%02x on bus %i\n",
> + count, reg, addr, adapter->nr);
> + for (i = 0; i < count; i++)
> + printf("0x%02x ", *(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"
> +" -b <bus_num> i2c bus number\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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