1 /* 2 * GPIO driver for RICOH583 power management chip. 3 * 4 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. 5 * Author: Laxman dewangan <ldewangan@nvidia.com> 6 * 7 * Based on code 8 * Copyright (C) 2011 RICOH COMPANY,LTD 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms and conditions of the GNU General Public License, 12 * version 2, as published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope it will be useful, but WITHOUT 15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 17 * more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program. If not, see <http://www.gnu.org/licenses/>. 21 * 22 */ 23 #include <linux/init.h> 24 #include <linux/kernel.h> 25 #include <linux/slab.h> 26 #include <linux/module.h> 27 #include <linux/platform_device.h> 28 #include <linux/device.h> 29 #include <linux/gpio.h> 30 #include <linux/mfd/rc5t583.h> 31 32 struct rc5t583_gpio { 33 struct gpio_chip gpio_chip; 34 struct rc5t583 *rc5t583; 35 }; 36 37 static int rc5t583_gpio_get(struct gpio_chip *gc, unsigned int offset) 38 { 39 struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc); 40 struct device *parent = rc5t583_gpio->rc5t583->dev; 41 uint8_t val = 0; 42 int ret; 43 44 ret = rc5t583_read(parent, RC5T583_GPIO_MON_IOIN, &val); 45 if (ret < 0) 46 return ret; 47 48 return !!(val & BIT(offset)); 49 } 50 51 static void rc5t583_gpio_set(struct gpio_chip *gc, unsigned int offset, int val) 52 { 53 struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc); 54 struct device *parent = rc5t583_gpio->rc5t583->dev; 55 if (val) 56 rc5t583_set_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset)); 57 else 58 rc5t583_clear_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset)); 59 } 60 61 static int rc5t583_gpio_dir_input(struct gpio_chip *gc, unsigned int offset) 62 { 63 struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc); 64 struct device *parent = rc5t583_gpio->rc5t583->dev; 65 int ret; 66 67 ret = rc5t583_clear_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset)); 68 if (ret < 0) 69 return ret; 70 71 /* Set pin to gpio mode */ 72 return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset)); 73 } 74 75 static int rc5t583_gpio_dir_output(struct gpio_chip *gc, unsigned offset, 76 int value) 77 { 78 struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc); 79 struct device *parent = rc5t583_gpio->rc5t583->dev; 80 int ret; 81 82 rc5t583_gpio_set(gc, offset, value); 83 ret = rc5t583_set_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset)); 84 if (ret < 0) 85 return ret; 86 87 /* Set pin to gpio mode */ 88 return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset)); 89 } 90 91 static int rc5t583_gpio_to_irq(struct gpio_chip *gc, unsigned offset) 92 { 93 struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc); 94 95 if (offset < RC5T583_MAX_GPIO) 96 return rc5t583_gpio->rc5t583->irq_base + 97 RC5T583_IRQ_GPIO0 + offset; 98 return -EINVAL; 99 } 100 101 static void rc5t583_gpio_free(struct gpio_chip *gc, unsigned offset) 102 { 103 struct rc5t583_gpio *rc5t583_gpio = gpiochip_get_data(gc); 104 struct device *parent = rc5t583_gpio->rc5t583->dev; 105 106 rc5t583_set_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset)); 107 } 108 109 static int rc5t583_gpio_probe(struct platform_device *pdev) 110 { 111 struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent); 112 struct rc5t583_platform_data *pdata = dev_get_platdata(rc5t583->dev); 113 struct rc5t583_gpio *rc5t583_gpio; 114 115 rc5t583_gpio = devm_kzalloc(&pdev->dev, sizeof(*rc5t583_gpio), 116 GFP_KERNEL); 117 if (!rc5t583_gpio) 118 return -ENOMEM; 119 120 rc5t583_gpio->gpio_chip.label = "gpio-rc5t583", 121 rc5t583_gpio->gpio_chip.owner = THIS_MODULE, 122 rc5t583_gpio->gpio_chip.free = rc5t583_gpio_free, 123 rc5t583_gpio->gpio_chip.direction_input = rc5t583_gpio_dir_input, 124 rc5t583_gpio->gpio_chip.direction_output = rc5t583_gpio_dir_output, 125 rc5t583_gpio->gpio_chip.set = rc5t583_gpio_set, 126 rc5t583_gpio->gpio_chip.get = rc5t583_gpio_get, 127 rc5t583_gpio->gpio_chip.to_irq = rc5t583_gpio_to_irq, 128 rc5t583_gpio->gpio_chip.ngpio = RC5T583_MAX_GPIO, 129 rc5t583_gpio->gpio_chip.can_sleep = true, 130 rc5t583_gpio->gpio_chip.parent = &pdev->dev; 131 rc5t583_gpio->gpio_chip.base = -1; 132 rc5t583_gpio->rc5t583 = rc5t583; 133 134 if (pdata && pdata->gpio_base) 135 rc5t583_gpio->gpio_chip.base = pdata->gpio_base; 136 137 platform_set_drvdata(pdev, rc5t583_gpio); 138 139 return devm_gpiochip_add_data(&pdev->dev, &rc5t583_gpio->gpio_chip, 140 rc5t583_gpio); 141 } 142 143 static struct platform_driver rc5t583_gpio_driver = { 144 .driver = { 145 .name = "rc5t583-gpio", 146 }, 147 .probe = rc5t583_gpio_probe, 148 }; 149 150 static int __init rc5t583_gpio_init(void) 151 { 152 return platform_driver_register(&rc5t583_gpio_driver); 153 } 154 subsys_initcall(rc5t583_gpio_init); 155 156 static void __exit rc5t583_gpio_exit(void) 157 { 158 platform_driver_unregister(&rc5t583_gpio_driver); 159 } 160 module_exit(rc5t583_gpio_exit); 161 162 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 163 MODULE_DESCRIPTION("GPIO interface for RC5T583"); 164 MODULE_LICENSE("GPL v2"); 165 MODULE_ALIAS("platform:rc5t583-gpio"); 166