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 inline struct rc5t583_gpio *to_rc5t583_gpio(struct gpio_chip *chip) 38 { 39 return container_of(chip, struct rc5t583_gpio, gpio_chip); 40 } 41 42 static int rc5t583_gpio_get(struct gpio_chip *gc, unsigned int offset) 43 { 44 struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc); 45 struct device *parent = rc5t583_gpio->rc5t583->dev; 46 uint8_t val = 0; 47 int ret; 48 49 ret = rc5t583_read(parent, RC5T583_GPIO_MON_IOIN, &val); 50 if (ret < 0) 51 return ret; 52 53 return !!(val & BIT(offset)); 54 } 55 56 static void rc5t583_gpio_set(struct gpio_chip *gc, unsigned int offset, int val) 57 { 58 struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc); 59 struct device *parent = rc5t583_gpio->rc5t583->dev; 60 if (val) 61 rc5t583_set_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset)); 62 else 63 rc5t583_clear_bits(parent, RC5T583_GPIO_IOOUT, BIT(offset)); 64 } 65 66 static int rc5t583_gpio_dir_input(struct gpio_chip *gc, unsigned int offset) 67 { 68 struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc); 69 struct device *parent = rc5t583_gpio->rc5t583->dev; 70 int ret; 71 72 ret = rc5t583_clear_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset)); 73 if (ret < 0) 74 return ret; 75 76 /* Set pin to gpio mode */ 77 return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset)); 78 } 79 80 static int rc5t583_gpio_dir_output(struct gpio_chip *gc, unsigned offset, 81 int value) 82 { 83 struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc); 84 struct device *parent = rc5t583_gpio->rc5t583->dev; 85 int ret; 86 87 rc5t583_gpio_set(gc, offset, value); 88 ret = rc5t583_set_bits(parent, RC5T583_GPIO_IOSEL, BIT(offset)); 89 if (ret < 0) 90 return ret; 91 92 /* Set pin to gpio mode */ 93 return rc5t583_clear_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset)); 94 } 95 96 static int rc5t583_gpio_to_irq(struct gpio_chip *gc, unsigned offset) 97 { 98 struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc); 99 100 if ((offset >= 0) && (offset < 8)) 101 return rc5t583_gpio->rc5t583->irq_base + 102 RC5T583_IRQ_GPIO0 + offset; 103 return -EINVAL; 104 } 105 106 static void rc5t583_gpio_free(struct gpio_chip *gc, unsigned offset) 107 { 108 struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc); 109 struct device *parent = rc5t583_gpio->rc5t583->dev; 110 111 rc5t583_set_bits(parent, RC5T583_GPIO_PGSEL, BIT(offset)); 112 } 113 114 static int rc5t583_gpio_probe(struct platform_device *pdev) 115 { 116 struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent); 117 struct rc5t583_platform_data *pdata = dev_get_platdata(rc5t583->dev); 118 struct rc5t583_gpio *rc5t583_gpio; 119 120 rc5t583_gpio = devm_kzalloc(&pdev->dev, sizeof(*rc5t583_gpio), 121 GFP_KERNEL); 122 if (!rc5t583_gpio) { 123 dev_warn(&pdev->dev, "Mem allocation for rc5t583_gpio failed"); 124 return -ENOMEM; 125 } 126 127 rc5t583_gpio->gpio_chip.label = "gpio-rc5t583", 128 rc5t583_gpio->gpio_chip.owner = THIS_MODULE, 129 rc5t583_gpio->gpio_chip.free = rc5t583_gpio_free, 130 rc5t583_gpio->gpio_chip.direction_input = rc5t583_gpio_dir_input, 131 rc5t583_gpio->gpio_chip.direction_output = rc5t583_gpio_dir_output, 132 rc5t583_gpio->gpio_chip.set = rc5t583_gpio_set, 133 rc5t583_gpio->gpio_chip.get = rc5t583_gpio_get, 134 rc5t583_gpio->gpio_chip.to_irq = rc5t583_gpio_to_irq, 135 rc5t583_gpio->gpio_chip.ngpio = RC5T583_MAX_GPIO, 136 rc5t583_gpio->gpio_chip.can_sleep = 1, 137 rc5t583_gpio->gpio_chip.dev = &pdev->dev; 138 rc5t583_gpio->gpio_chip.base = -1; 139 rc5t583_gpio->rc5t583 = rc5t583; 140 141 if (pdata && pdata->gpio_base) 142 rc5t583_gpio->gpio_chip.base = pdata->gpio_base; 143 144 platform_set_drvdata(pdev, rc5t583_gpio); 145 146 return gpiochip_add(&rc5t583_gpio->gpio_chip); 147 } 148 149 static int rc5t583_gpio_remove(struct platform_device *pdev) 150 { 151 struct rc5t583_gpio *rc5t583_gpio = platform_get_drvdata(pdev); 152 153 return gpiochip_remove(&rc5t583_gpio->gpio_chip); 154 } 155 156 static struct platform_driver rc5t583_gpio_driver = { 157 .driver = { 158 .name = "rc5t583-gpio", 159 .owner = THIS_MODULE, 160 }, 161 .probe = rc5t583_gpio_probe, 162 .remove = rc5t583_gpio_remove, 163 }; 164 165 static int __init rc5t583_gpio_init(void) 166 { 167 return platform_driver_register(&rc5t583_gpio_driver); 168 } 169 subsys_initcall(rc5t583_gpio_init); 170 171 static void __exit rc5t583_gpio_exit(void) 172 { 173 platform_driver_unregister(&rc5t583_gpio_driver); 174 } 175 module_exit(rc5t583_gpio_exit); 176 177 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 178 MODULE_DESCRIPTION("GPIO interface for RC5T583"); 179 MODULE_LICENSE("GPL v2"); 180 MODULE_ALIAS("platform:rc5t583-gpio"); 181