From 04c79cbd5f8f773aa7823feec6e77862e7e6426f Mon Sep 17 00:00:00 2001 From: Dirk Behme Date: Mon, 15 Jul 2013 15:58:27 +0200 Subject: mxc_gpio: Correct the GPIO handling in gpio_direction_output() Setting the direction and an output value should be done by First, set the desired output value. Then, switch to output. If this is done in the inverse order, like at the moment, there can be a glitch on the GPIO line while switching first the old output value and aftwards the new one. Fix this by inverting the order of the direction/set_value calls. Signed-off-by: Dirk Behme Acked-by: Stefano Babic --- drivers/gpio/mxc_gpio.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/gpio') diff --git a/drivers/gpio/mxc_gpio.c b/drivers/gpio/mxc_gpio.c index a388064..1d820d4 100644 --- a/drivers/gpio/mxc_gpio.c +++ b/drivers/gpio/mxc_gpio.c @@ -143,10 +143,10 @@ int gpio_direction_input(unsigned gpio) int gpio_direction_output(unsigned gpio, int value) { - int ret = mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_OUT); + int ret = gpio_set_value(gpio, value); if (ret < 0) return ret; - return gpio_set_value(gpio, value); + return mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_OUT); } -- cgit v1.1 From 61c1775f16ed122a07168545afbc1a04ece2bc22 Mon Sep 17 00:00:00 2001 From: Dan Murphy Date: Thu, 11 Jul 2013 13:10:27 -0500 Subject: gpio: tca642x: Add the tca642x gpio expander driver Add the tca642x gpio expander driver Datasheet: http://www.ti.com/product/tca6424a Signed-off-by: Dan Murphy --- drivers/gpio/Makefile | 1 + drivers/gpio/tca642x.c | 333 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 334 insertions(+) create mode 100644 drivers/gpio/tca642x.c (limited to 'drivers/gpio') 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 + * + * 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 +#include +#include + +/* 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 */ -- cgit v1.1