1/* 2 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org> 3 * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org> 4 * Copyright (C) 2009 Florian Fainelli <florian@openwrt.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21#include <linux/module.h> 22#include <linux/gpio.h> 23 24#include <asm/mach-ar7/gpio.h> 25 26struct ar7_gpio_chip { 27 void __iomem *regs; 28 struct gpio_chip chip; 29}; 30 31static int ar7_gpio_get_value(struct gpio_chip *chip, unsigned gpio) 32{ 33 struct ar7_gpio_chip *gpch = 34 container_of(chip, struct ar7_gpio_chip, chip); 35 void __iomem *gpio_in = gpch->regs + AR7_GPIO_INPUT; 36 37 return readl(gpio_in) & (1 << gpio); 38} 39 40static void ar7_gpio_set_value(struct gpio_chip *chip, 41 unsigned gpio, int value) 42{ 43 struct ar7_gpio_chip *gpch = 44 container_of(chip, struct ar7_gpio_chip, chip); 45 void __iomem *gpio_out = gpch->regs + AR7_GPIO_OUTPUT; 46 unsigned tmp; 47 48 tmp = readl(gpio_out) & ~(1 << gpio); 49 if (value) 50 tmp |= 1 << gpio; 51 writel(tmp, gpio_out); 52} 53 54static int ar7_gpio_direction_input(struct gpio_chip *chip, unsigned gpio) 55{ 56 struct ar7_gpio_chip *gpch = 57 container_of(chip, struct ar7_gpio_chip, chip); 58 void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR; 59 60 writel(readl(gpio_dir) | (1 << gpio), gpio_dir); 61 62 return 0; 63} 64 65static int ar7_gpio_direction_output(struct gpio_chip *chip, 66 unsigned gpio, int value) 67{ 68 struct ar7_gpio_chip *gpch = 69 container_of(chip, struct ar7_gpio_chip, chip); 70 void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR; 71 72 ar7_gpio_set_value(chip, gpio, value); 73 writel(readl(gpio_dir) & ~(1 << gpio), gpio_dir); 74 75 return 0; 76} 77 78static struct ar7_gpio_chip ar7_gpio_chip = { 79 .chip = { 80 .label = "ar7-gpio", 81 .direction_input = ar7_gpio_direction_input, 82 .direction_output = ar7_gpio_direction_output, 83 .set = ar7_gpio_set_value, 84 .get = ar7_gpio_get_value, 85 .base = 0, 86 .ngpio = AR7_GPIO_MAX, 87 } 88}; 89 90int ar7_gpio_enable(unsigned gpio) 91{ 92 void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE; 93 94 writel(readl(gpio_en) | (1 << gpio), gpio_en); 95 96 return 0; 97} 98EXPORT_SYMBOL(ar7_gpio_enable); 99 100int ar7_gpio_disable(unsigned gpio) 101{ 102 void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE; 103 104 writel(readl(gpio_en) & ~(1 << gpio), gpio_en); 105 106 return 0; 107} 108EXPORT_SYMBOL(ar7_gpio_disable); 109 110static int __init ar7_gpio_init(void) 111{ 112 int ret; 113 114 ar7_gpio_chip.regs = ioremap_nocache(AR7_REGS_GPIO, 0x10); 115 116 if (!ar7_gpio_chip.regs) { 117 printk(KERN_ERR "ar7-gpio: failed to ioremap regs\n"); 118 } 119 120 ret = gpiochip_add(&ar7_gpio_chip.chip); 121 if (ret) { 122 printk(KERN_ERR "ar7-gpio: failed to add gpiochip\n"); 123 return ret; 124 } 125 printk(KERN_INFO "ar7-gpio: registered %d GPIOs\n", 126 ar7_gpio_chip.chip.ngpio); 127 return ret; 128} 129arch_initcall(ar7_gpio_init); 130