/* * Loongson-2F/3A/3B GPIO Support * * Copyright (c) 2008 Richard Liu, STMicroelectronics <richard.liu@st.com> * Copyright (c) 2008-2010 Arnaud Patard <apatard@mandriva.com> * Copyright (c) 2013 Hongbing Hu <huhb@lemote.com> * Copyright (c) 2014 Huacai Chen <chenhc@lemote.com> * * 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. */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/module.h> #include <linux/spinlock.h> #include <linux/err.h> #include <asm/types.h> #include <loongson.h> #include <linux/gpio.h> #define STLS2F_N_GPIO 4 #define STLS3A_N_GPIO 16 #ifdef CONFIG_CPU_LOONGSON3 #define LOONGSON_N_GPIO STLS3A_N_GPIO #else #define LOONGSON_N_GPIO STLS2F_N_GPIO #endif #define LOONGSON_GPIO_IN_OFFSET 16 static DEFINE_SPINLOCK(gpio_lock); static int loongson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) { u32 temp; u32 mask; spin_lock(&gpio_lock); mask = 1 << gpio; temp = LOONGSON_GPIOIE; temp |= mask; LOONGSON_GPIOIE = temp; spin_unlock(&gpio_lock); return 0; } static int loongson_gpio_direction_output(struct gpio_chip *chip, unsigned gpio, int level) { u32 temp; u32 mask; gpio_set_value(gpio, level); spin_lock(&gpio_lock); mask = 1 << gpio; temp = LOONGSON_GPIOIE; temp &= (~mask); LOONGSON_GPIOIE = temp; spin_unlock(&gpio_lock); return 0; } static int loongson_gpio_get_value(struct gpio_chip *chip, unsigned gpio) { u32 val; u32 mask; mask = 1 << (gpio + LOONGSON_GPIO_IN_OFFSET); spin_lock(&gpio_lock); val = LOONGSON_GPIODATA; spin_unlock(&gpio_lock); return (val & mask) != 0; } static void loongson_gpio_set_value(struct gpio_chip *chip, unsigned gpio, int value) { u32 val; u32 mask; mask = 1 << gpio; spin_lock(&gpio_lock); val = LOONGSON_GPIODATA; if (value) val |= mask; else val &= (~mask); LOONGSON_GPIODATA = val; spin_unlock(&gpio_lock); } static struct gpio_chip loongson_chip = { .label = "Loongson-gpio-chip", .direction_input = loongson_gpio_direction_input, .get = loongson_gpio_get_value, .direction_output = loongson_gpio_direction_output, .set = loongson_gpio_set_value, .base = 0, .ngpio = LOONGSON_N_GPIO, .can_sleep = false, }; static int __init loongson_gpio_setup(void) { return gpiochip_add(&loongson_chip); } postcore_initcall(loongson_gpio_setup);