nuttx-apps/system/i2c/i2c_dev.c
David Alessio 839efa6669 Merged in david_alessio/apps/bugfix/i2ctool-dev-clobbers-slave-config (pull request #198)
Bugfix/i2ctool dev clobbers slave config

* friendlier I2C "knock-knock" uses only read request

    While many I2C slave devices have multiple indexed registers, some have
    only one register and it's not indexed.  For example, the I2C bus switch
    TCA9548A has only a Control Register, attempting to index to "Reg[0]"
    alters its contents to 0x00 disabling all subordinate buses.  This patch
    fixes that problem by simply trying to read something/anything from the
    slave.  This also helps coax out slaves with register files that start
    from a higher index, i.e. the AT24CS0x, FLASH chips with a UUID that
    appears as a 2nd I2C slave at (address+8), report their serial number at
    Reg[80]-Reg[8F] and will NAK a read of Reg[0].

* modify get/set to prevent write of reg index if not specifed

Approved-by: Gregory Nutt <gnutt@nuttx.org>
2019-08-20 20:29:21 +00:00

201 lines
5.6 KiB
C

/****************************************************************************
* apps/system/i2c/i2c_dev.c
*
* Copyright (C) 2011, 2016, 2018 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdlib.h>
#include <nuttx/i2c/i2c_master.h>
#include "i2ctool.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: i2ccmd_dev
****************************************************************************/
int i2ccmd_dev(FAR struct i2ctool_s *i2ctool, int argc, char **argv)
{
struct i2c_msg_s msg;
FAR char *ptr;
uint8_t regaddr;
uint8_t saveaddr;
long first;
long last;
int addr;
int nargs;
int argndx;
int ret;
int fd;
int i;
int j;
/* A register address other than zero may be provided on the command line.
* However, for backward compatibility, the address zero will be used
* unless the address is specifically included on the command line for
* this command.
*/
saveaddr = i2ctool->regaddr;
i2ctool->regaddr = 0;
/* Parse any command line arguments */
for (argndx = 1; argndx < argc; )
{
/* Break out of the loop when the last option has been parsed */
ptr = argv[argndx];
if (*ptr != '-')
{
break;
}
/* Otherwise, check for common options */
nargs = i2ctool_common_args(i2ctool, &argv[argndx]);
if (nargs < 0)
{
goto errout;
}
argndx += nargs;
}
/* There should be exactly two more things on the command line: The first and
* last addresses to be probed.
*/
if (argndx + 1 < argc)
{
first = strtol(argv[argndx], NULL, 16);
last = strtol(argv[argndx + 1], NULL, 16);
if (first < 0 || first > 0x7f || last < 0 || last > 0x7f || first > last)
{
i2ctool_printf(i2ctool, g_i2cargrange, argv[0]);
goto errout;
}
argndx += 2;
}
else
{
i2ctool_printf(i2ctool, g_i2cargrequired, argv[0]);
goto errout;
}
if (argndx != argc)
{
i2ctool_printf(i2ctool, g_i2ctoomanyargs, argv[0]);
goto errout;
}
/* Get a handle to the I2C bus */
fd = i2cdev_open(i2ctool->bus);
if (fd < 0)
{
i2ctool_printf(i2ctool, "Failed to get bus %d\n", i2ctool->bus);
goto errout;
}
/* Probe each address */
i2ctool_printf(i2ctool, " 0 1 2 3 4 5 6 7 8 9 a b c d e f\n");
for (i = 0; i < 128; i += 16)
{
i2ctool_printf(i2ctool, "%02x: ", i);
for (j = 0; j < 16; j++)
{
/* Skip addresses that are out of the selected range */
addr = i + j;
if (addr < first || addr > last)
{
i2ctool_printf(i2ctool, " ");
continue;
}
/* Set up data structures */
regaddr = i2ctool->regaddr;
msg.frequency = i2ctool->freq;
msg.addr = addr;
msg.flags = I2C_M_READ;
msg.buffer = &regaddr;
msg.length = 1;
ret = i2cdev_transfer(fd, &msg, 1);
if (ret == OK)
{
i2ctool_printf(i2ctool, "%02x ", addr);
}
else
{
i2ctool_printf(i2ctool, "-- ");
}
i2ctool_flush(i2ctool);
}
i2ctool_printf(i2ctool, "\n");
i2ctool_flush(i2ctool);
}
(void)close(fd);
errout:
/* Restore the previous "sticky" register address unless a new register
* address was provided on the command line. In that case the new
* register address is retained.
*/
if (i2ctool->regaddr == 0)
{
i2ctool->regaddr = saveaddr;
}
return OK;
}