From 5a5bc7607501aab650ddd3c568d92a026297d1d8 Mon Sep 17 00:00:00 2001 From: "Ye.Li" Date: Mon, 13 Jan 2014 16:27:39 +0800 Subject: ENGR00315499-18 driver:MAX7310: Add GPIO expander driver for MAX7310 Implement simple functionalities for MAX7310 GPIO input and output. Because MAX7310 is a off-chip device and need to co-exist with on-chip GPIO, new APIs are added specifically for expander device. CONFIG_MAX7310_IOEXP is used to enable the MAX7310 driver. The I2C related configurations also need to set together. Signed-off-by: Ye.Li Signed-off-by: Nitin Garg (cherry picked from commit e3b699dab2c92268799b56c28c6a8fcda4f6110b) Signed-off-by: Peng Fan Conflicts: drivers/gpio/Makefile --- include/gpio_exp.h | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 include/gpio_exp.h (limited to 'include/gpio_exp.h') diff --git a/include/gpio_exp.h b/include/gpio_exp.h new file mode 100644 index 0000000..6dc5eed --- /dev/null +++ b/include/gpio_exp.h @@ -0,0 +1,73 @@ +/* + * Copyright (C) 2014 Freescale Semiconductor, Inc. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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. + */ + +#ifndef __GPIO_EXP_H +#define __GPIO_EXP_H + +#ifndef CONFIG_IOEXP_DEV_PINS_NUM +#define CONFIG_IOEXP_DEV_PINS_NUM 8 +#endif + +#ifndef CONFIG_IOEXP_DEVICES_NUM +#define CONFIG_IOEXP_DEVICES_NUM 1 +#endif + +/*Define for building ioexp gpio, port starts from 1, index starts from 0*/ +#define IOEXP_GPIO_NR(port, index) \ + ((((port)-1)*CONFIG_IOEXP_DEV_PINS_NUM)+ \ + ((index)&(CONFIG_IOEXP_DEV_PINS_NUM-1))) + +/*Get the device number from a ioexp gpio*/ +#define IOEXP_GPIO_TO_DEVICE(gpio_nr) \ + (gpio_nr / CONFIG_IOEXP_DEV_PINS_NUM) + +/*Get the port number from a ioexp gpio*/ +#define IOEXP_GPIO_TO_PORT(gpio_nr) \ + ((gpio_nr / CONFIG_IOEXP_DEV_PINS_NUM) + 1) + +/*Get the pin number from a ioexp gpio*/ +#define IOEXP_GPIO_TO_PIN(gpio_nr) \ + (gpio_nr % CONFIG_IOEXP_DEV_PINS_NUM) + +/** + * Make a GPIO an input. + * + * @param gpio GPIO number + * @return 0 if ok, -1 on error + */ +int gpio_exp_direction_input(unsigned gpio); + +/** + * Make a GPIO an output, and set its value. + * + * @param gpio GPIO number + * @param value GPIO value (0 for low or 1 for high) + * @return 0 if ok, -1 on error + */ +int gpio_exp_direction_output(unsigned gpio, int value); + +/** + * Setup the io expander's port. + * + * @param port IO expander port , starts from 1 + * @param i2c_bus_id i2c bus index, starts from 0 + * @param i2c_slave_addr i2c address of the io expander port + * @return 0 if ok, -1 on error + */ +int gpio_exp_setup_port(int port, int i2c_bus_id, int i2c_slave_addr); + +#endif /*__GPIO_EXP_H*/ -- cgit v1.1