u-boot/drivers/gpio/tca642x.c

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/*
* Copyright 2013 Texas Instruments, Inc.
* Author: Dan Murphy <dmurphy@ti.com>
*
* Derived work from the pca953x.c driver
*
* 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 <i2c.h>
#include <tca642x.h>
/* tca642x register address definitions */
struct tca642x_bank_info tca642x_regs[] = {
{ .input_reg = 0x00,
.output_reg = 0x04,
.polarity_reg = 0x08,
.configuration_reg = 0x0c },
{ .input_reg = 0x01,
.output_reg = 0x05,
.polarity_reg = 0x09,
.configuration_reg = 0x0d },
{ .input_reg = 0x02,
.output_reg = 0x06,
.polarity_reg = 0x0a,
.configuration_reg = 0x0e },
};
/*
* Modify masked bits in register
*/
static int tca642x_reg_write(uchar chip, uint8_t addr,
uint8_t reg_bit, uint8_t data)
{
uint8_t valw;
int org_bus_num;
int ret;
org_bus_num = i2c_get_bus_num();
i2c_set_bus_num(CFG_SYS_I2C_TCA642X_BUS_NUM);
if (i2c_read(chip, addr, 1, (uint8_t *)&valw, 1)) {
printf("Could not read before writing\n");
ret = -1;
goto error;
}
valw &= ~reg_bit;
valw |= data;
ret = i2c_write(chip, addr, 1, (u8 *)&valw, 1);
error:
i2c_set_bus_num(org_bus_num);
return ret;
}
static int tca642x_reg_read(uchar chip, uint8_t addr, uint8_t *data)
{
uint8_t valw;
int org_bus_num;
int ret = 0;
org_bus_num = i2c_get_bus_num();
i2c_set_bus_num(CFG_SYS_I2C_TCA642X_BUS_NUM);
if (i2c_read(chip, addr, 1, (u8 *)&valw, 1)) {
ret = -1;
goto error;
}
*data = valw;
error:
i2c_set_bus_num(org_bus_num);
return ret;
}
/*
* Set output value of IO pins in 'reg_bit' to corresponding value in 'data'
* 0 = low, 1 = high
*/
int tca642x_set_val(uchar chip, uint8_t gpio_bank,
uint8_t reg_bit, uint8_t data)
{
uint8_t out_reg = tca642x_regs[gpio_bank].output_reg;
return tca642x_reg_write(chip, out_reg, reg_bit, data);
}
/*
* Set read polarity of IO pins in 'reg_bit' to corresponding value in 'data'
* 0 = read pin value, 1 = read inverted pin value
*/
int tca642x_set_pol(uchar chip, uint8_t gpio_bank,
uint8_t reg_bit, uint8_t data)
{
uint8_t pol_reg = tca642x_regs[gpio_bank].polarity_reg;
return tca642x_reg_write(chip, pol_reg, reg_bit, data);
}
/*
* Set direction of IO pins in 'reg_bit' to corresponding value in 'data'
* 0 = output, 1 = input
*/
int tca642x_set_dir(uchar chip, uint8_t gpio_bank,
uint8_t reg_bit, uint8_t data)
{
uint8_t config_reg = tca642x_regs[gpio_bank].configuration_reg;
return tca642x_reg_write(chip, config_reg, reg_bit, data);
}
/*
* Read current logic level of all IO pins
*/
int tca642x_get_val(uchar chip, uint8_t gpio_bank)
{
uint8_t val;
uint8_t in_reg = tca642x_regs[gpio_bank].input_reg;
if (tca642x_reg_read(chip, in_reg, &val) < 0)
return -1;
return (int)val;
}
/*
* Set the inital register states for the tca642x gpio expander
*/
int tca642x_set_inital_state(uchar chip, struct tca642x_bank_info init_data[])
{
int i, ret;
uint8_t config_reg;
uint8_t polarity_reg;
uint8_t output_reg;
for (i = 0; i < 3; i++) {
config_reg = tca642x_regs[i].configuration_reg;
ret = tca642x_reg_write(chip, config_reg, 0xff,
init_data[i].configuration_reg);
polarity_reg = tca642x_regs[i].polarity_reg;
ret = tca642x_reg_write(chip, polarity_reg, 0xff,
init_data[i].polarity_reg);
output_reg = tca642x_regs[i].output_reg;
ret = tca642x_reg_write(chip, output_reg, 0xff,
init_data[i].output_reg);
}
return ret;
}
#if defined(CONFIG_CMD_TCA642X) && !defined(CONFIG_SPL_BUILD)
/*
* Display tca642x information
*/
static int tca642x_info(uchar chip)
{
int i, j;
uint8_t data;
printf("tca642x@ 0x%x (%d pins):\n", chip, 24);
for (i = 0; i < 3; i++) {
printf("Bank %i\n", i);
if (tca642x_reg_read(chip,
tca642x_regs[i].configuration_reg,
&data) < 0)
return -1;
printf("\tConfiguration: ");
for (j = 7; j >= 0; j--)
printf("%c", data & (1 << j) ? 'i' : 'o');
printf("\n");
if (tca642x_reg_read(chip,
tca642x_regs[i].polarity_reg, &data) < 0)
return -1;
printf("\tPolarity: ");
for (j = 7; j >= 0; j--)
printf("%c", data & (1 << j) ? '1' : '0');
printf("\n");
if (tca642x_reg_read(chip,
tca642x_regs[i].input_reg, &data) < 0)
return -1;
printf("\tInput value: ");
for (j = 7; j >= 0; j--)
printf("%c", data & (1 << j) ? '1' : '0');
printf("\n");
if (tca642x_reg_read(chip,
tca642x_regs[i].output_reg, &data) < 0)
return -1;
printf("\tOutput value: ");
for (j = 7; j >= 0; j--)
printf("%c", data & (1 << j) ? '1' : '0');
printf("\n");
}
return 0;
}
static int tca642x_get_bank(int pin)
{
int gpio_bank;
if (pin <= 7) {
gpio_bank = 0;
} else if ((pin >= 10) && (pin <= 17)) {
gpio_bank = 1;
} else if ((pin >= 20) && (pin <= 27)) {
gpio_bank = 2;
} else {
printf("Requested pin is not available\n");
gpio_bank = -1;
}
return gpio_bank;
}
static struct cmd_tbl cmd_tca642x[] = {
U_BOOT_CMD_MKENT(device, 3, 0, (void *)TCA642X_CMD_DEVICE, "", ""),
U_BOOT_CMD_MKENT(output, 4, 0, (void *)TCA642X_CMD_OUTPUT, "", ""),
U_BOOT_CMD_MKENT(input, 3, 0, (void *)TCA642X_CMD_INPUT, "", ""),
U_BOOT_CMD_MKENT(invert, 4, 0, (void *)TCA642X_CMD_INVERT, "", ""),
U_BOOT_CMD_MKENT(info, 2, 0, (void *)TCA642X_CMD_INFO, "", ""),
};
static int do_tca642x(struct cmd_tbl *cmdtp, int flag, int argc,
char *const argv[])
{
static uchar chip = CFG_SYS_I2C_TCA642X_ADDR;
int ret = CMD_RET_USAGE, val;
int gpio_bank = 0;
uint8_t bank_shift;
ulong ul_arg2 = 0;
ulong ul_arg3 = 0;
struct cmd_tbl *c;
c = find_cmd_tbl(argv[1], cmd_tca642x, ARRAY_SIZE(cmd_tca642x));
/* All commands but "device" require 'maxargs' arguments */
if (!c ||
!((argc == (c->maxargs)) ||
(((int)c->cmd == TCA642X_CMD_DEVICE) &&
(argc == (c->maxargs - 1))))) {
return CMD_RET_USAGE;
}
/* arg2 used as chip number or pin number */
if (argc > 2)
ul_arg2 = dectoul(argv[2], NULL);
/* arg3 used as pin or invert value */
if (argc > 3)
ul_arg3 = dectoul(argv[3], NULL) & 0x1;
switch ((int)c->cmd) {
case TCA642X_CMD_INFO:
ret = tca642x_info(chip);
if (ret)
ret = CMD_RET_FAILURE;
break;
case TCA642X_CMD_DEVICE:
if (argc == 3)
chip = (uint8_t)ul_arg2;
printf("Current device address: 0x%x\n", chip);
ret = CMD_RET_SUCCESS;
break;
case TCA642X_CMD_INPUT:
gpio_bank = tca642x_get_bank(ul_arg2);
if (gpio_bank < 0) {
ret = CMD_RET_FAILURE;
goto error;
}
bank_shift = ul_arg2 - (gpio_bank * 10);
ret = tca642x_set_dir(chip, gpio_bank, (1 << bank_shift),
TCA642X_DIR_IN << bank_shift);
val = (tca642x_get_val(chip, gpio_bank) &
(1 << bank_shift)) != 0;
if (ret)
ret = CMD_RET_FAILURE;
else
printf("chip 0x%02x, pin 0x%lx = %d\n", chip,
ul_arg2, val);
break;
case TCA642X_CMD_OUTPUT:
gpio_bank = tca642x_get_bank(ul_arg2);
if (gpio_bank < 0) {
ret = CMD_RET_FAILURE;
goto error;
}
bank_shift = ul_arg2 - (gpio_bank * 10);
ret = tca642x_set_dir(chip, gpio_bank, (1 << bank_shift),
(TCA642X_DIR_OUT << bank_shift));
if (!ret)
ret = tca642x_set_val(chip,
gpio_bank, (1 << bank_shift),
(ul_arg3 << bank_shift));
if (ret)
ret = CMD_RET_FAILURE;
break;
case TCA642X_CMD_INVERT:
gpio_bank = tca642x_get_bank(ul_arg2);
if (gpio_bank < 0) {
ret = CMD_RET_FAILURE;
goto error;
}
bank_shift = ul_arg2 - (gpio_bank * 10);
ret = tca642x_set_pol(chip, gpio_bank, (1 << bank_shift),
(ul_arg3 << bank_shift));
if (ret)
ret = CMD_RET_FAILURE;
break;
}
error:
if (ret == CMD_RET_FAILURE)
eprintf("Error talking to chip at 0x%x\n", chip);
return ret;
}
U_BOOT_CMD(
tca642x, 5, 1, do_tca642x,
"tca642x gpio access",
"device [dev]\n"
" - show or set current device address\n"
"tca642x info\n"
" - display info for current chip\n"
"tca642x output pin 0|1\n"
" - set pin as output and drive low or high\n"
"tca642x invert pin 0|1\n"
" - disable/enable polarity inversion for reads\n"
"tca642x input pin\n"
" - set pin as input and read value"
);
#endif /* CONFIG_CMD_TCA642X */