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 > --- > v4 : > updated as per Sascha and Marc's comments > use bus 0 as a default for i2c_read & write > replace malloc with xmalloc > fix simple_strtol configuration for parameters > 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 | 212 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 221 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..1e617f6 > --- /dev/null > +++ b/commands/i2c.c > @@ -0,0 +1,212 @@ > +/* > + * i2c.c - i2c commands > + * > + * Copyright (c) 2010 Eric Bénard , 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 > +#include > +#include > +#include > +#include > +#include > + > +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, 0); > + stopaddr = simple_strtol(argv[3], NULL, 0); > + 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 = 0, opt, i; > + u8 *buf; > + u8 tmp; > + > + while ((opt = getopt(argc, argv, "a:b:r:v")) > 0) { > + switch (opt) { > + case 'a': > + addr = simple_strtol(optarg, NULL, 0); > + break; > + case 'r': > + reg = simple_strtol(optarg, NULL, 0); > + break; > + case 'b': > + adapter = i2c_get_adapter(simple_strtoul(optarg, NULL, 0)); I'd just save the optarg in a variable... > + break; > + case 'v': > + verbose = 1; > + break; > + } > + } > + > + count = argc - optind; > + > + if ((addr < 0) || (reg < 0) || (count == 0) || (addr > 0x7F)) > + return COMMAND_ERROR_USAGE; > + > + if (!adapter) > + adapter = i2c_get_adapter(0); and use it here. Because if you specify an invalid adapter number, adapter 0 will be used silently (if it exists). > + if (!adapter) > + return -ENODEV; > + > + client.adapter = adapter; > + client.addr = addr; > + > + buf = xmalloc(count); > + for (i = 0; i < count; i++) > + *(buf + i) = (char) simple_strtol(argv[optind+i], NULL, 16); > + > + ret = i2c_write_reg(&client, reg, buf, count); > + if (ret != count) > + goto out; better set a return value indicating an error here... > + > + 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)); > + printf("\n"); > + } > + > +out: > + free(buf); > + return 0; ... and return it here. > +} > + > +static const __maybe_unused char cmd_i2c_write_help[] = > +"Usage: i2c_write [OPTION] ... hexdatas\n" > +"write to i2c device.\n" > +" -a 0x i2c device address\n" > +" -b i2c bus number (default = 0)\n" > +" -r 0x 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 = 0, opt; > + > + while ((opt = getopt(argc, argv, "a:b:c:r:v")) > 0) { > + switch (opt) { > + case 'a': > + addr = simple_strtol(optarg, NULL, 0); > + break; > + case 'c': > + count = simple_strtoul(optarg, NULL, 0); > + break; > + case 'b': > + adapter = i2c_get_adapter(simple_strtoul(optarg, NULL, 0)); > + break; > + case 'r': > + reg = simple_strtol(optarg, NULL, 0); > + break; > + case 'v': > + verbose = 1; > + break; > + } > + } > + > + if ((addr < 0) || (reg < 0) || (count == 0) || (addr > 0x7F)) > + return COMMAND_ERROR_USAGE; > + > + if (!adapter) > + adapter = i2c_get_adapter(0); > + if (!adapter) > + return -ENODEV; > + > + client.adapter = adapter; > + client.addr = addr; > + > + buf = xmalloc(count); > + 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"); > + ret = 0; > + } > + > + free(buf); > + return ret; > +} > + > +static const __maybe_unused char cmd_i2c_read_help[] = > +"Usage: i2c_read [OPTION]\n" > +"read i2c device.\n" > +" -a 0x i2c device address\n" > +" -b i2c bus number (default = 0)\n" > +" -r 0x start register\n" > +" -c 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 cheers, Marc -- Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |