diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/Makefile | 1 | ||||
| -rw-r--r-- | drivers/gpio/tca642x.c | 333 |
2 files changed, 334 insertions, 0 deletions
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index af94bf5..71ddb00 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -33,6 +33,7 @@ COBJS-$(CONFIG_BCM2835_GPIO) += bcm2835_gpio.o COBJS-$(CONFIG_S3C2440_GPIO) += s3c2440_gpio.o COBJS-$(CONFIG_XILINX_GPIO) += xilinx_gpio.o COBJS-$(CONFIG_ADI_GPIO2) += adi_gpio2.o +COBJS-$(CONFIG_TCA642X) += tca642x.o COBJS := $(COBJS-y) SRCS := $(COBJS:.o=.c) diff --git a/drivers/gpio/tca642x.c b/drivers/gpio/tca642x.c new file mode 100644 index 0000000..6386835 --- /dev/null +++ b/drivers/gpio/tca642x.c @@ -0,0 +1,333 @@ +/* + * 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 */ |