drivers/gpio/tca642x.c - u-boot - Git at Google

 /*
  * 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 <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(CONFIG_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(CONFIG_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;
 }

 #ifdef CONFIG_CMD_TCA642X
 /*
  * 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;
 }

 cmd_tbl_t 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, "", ""),
 };

 int do_tca642x(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	static uchar chip = CONFIG_SYS_I2C_TCA642X_ADDR;
 	int ret = CMD_RET_USAGE, val;
 	uint8_t gpio_bank = 0;
 	uint8_t bank_shift;
 	ulong ul_arg2 = 0;
 	ulong ul_arg3 = 0;
 	cmd_tbl_t *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 = simple_strtoul(argv[2], NULL, 10);

 	/* arg3 used as pin or invert value */
 	if (argc > 3) {
 		ul_arg3 = simple_strtoul(argv[3], NULL, 10) & 0x1;
 		if (ul_arg2 <= 7) {
 			gpio_bank = 0;
 		} else if ((ul_arg2 >= 10) && (ul_arg2 <= 17)) {
 			gpio_bank = 1;
 		} else if ((ul_arg2 >= 20) && (ul_arg2 <= 27)) {
 			gpio_bank = 2;
 		} else {
 			printf("Requested pin is not available\n");
 			ret = CMD_RET_FAILURE;
 			goto error;
 		}
 	}

 	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:
 		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:
 		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:
 		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 */
	/*
	* 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 <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(CONFIG_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(CONFIG_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;
	}

	#ifdef CONFIG_CMD_TCA642X
	/*
	* 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;
	}

	cmd_tbl_t 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, "", ""),
	};

	int do_tca642x(cmd_tbl_t cmdtp, int flag, int argc, char const argv[])
	{
	static uchar chip = CONFIG_SYS_I2C_TCA642X_ADDR;
	int ret = CMD_RET_USAGE, val;
	uint8_t gpio_bank = 0;
	uint8_t bank_shift;
	ulong ul_arg2 = 0;
	ulong ul_arg3 = 0;
	cmd_tbl_t *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 = simple_strtoul(argv[2], NULL, 10);

	/* arg3 used as pin or invert value */
	if (argc > 3) {
	ul_arg3 = simple_strtoul(argv[3], NULL, 10) & 0x1;
	if (ul_arg2 <= 7) {
	gpio_bank = 0;
	} else if ((ul_arg2 >= 10) && (ul_arg2 <= 17)) {
	gpio_bank = 1;
	} else if ((ul_arg2 >= 20) && (ul_arg2 <= 27)) {
	gpio_bank = 2;
	} else {
	printf("Requested pin is not available\n");
	ret = CMD_RET_FAILURE;
	goto error;
	}
	}

	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:
	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:
	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:
	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 */