1 /* 2 * gpiolib support for Wolfson WM835x PMICs 3 * 4 * Copyright 2009 Wolfson Microelectronics PLC. 5 * 6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 * 13 */ 14 15 #include <linux/kernel.h> 16 #include <linux/slab.h> 17 #include <linux/module.h> 18 #include <linux/gpio.h> 19 #include <linux/mfd/core.h> 20 #include <linux/platform_device.h> 21 #include <linux/seq_file.h> 22 23 #include <linux/mfd/wm8350/core.h> 24 #include <linux/mfd/wm8350/gpio.h> 25 26 struct wm8350_gpio_data { 27 struct wm8350 *wm8350; 28 struct gpio_chip gpio_chip; 29 }; 30 31 static inline struct wm8350_gpio_data *to_wm8350_gpio(struct gpio_chip *chip) 32 { 33 return container_of(chip, struct wm8350_gpio_data, gpio_chip); 34 } 35 36 static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset) 37 { 38 struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip); 39 struct wm8350 *wm8350 = wm8350_gpio->wm8350; 40 41 return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O, 42 1 << offset); 43 } 44 45 static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset) 46 { 47 struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip); 48 struct wm8350 *wm8350 = wm8350_gpio->wm8350; 49 int ret; 50 51 ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL); 52 if (ret < 0) 53 return ret; 54 55 if (ret & (1 << offset)) 56 return 1; 57 else 58 return 0; 59 } 60 61 static void wm8350_gpio_set(struct gpio_chip *chip, unsigned offset, int value) 62 { 63 struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip); 64 struct wm8350 *wm8350 = wm8350_gpio->wm8350; 65 66 if (value) 67 wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset); 68 else 69 wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset); 70 } 71 72 static int wm8350_gpio_direction_out(struct gpio_chip *chip, 73 unsigned offset, int value) 74 { 75 struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip); 76 struct wm8350 *wm8350 = wm8350_gpio->wm8350; 77 int ret; 78 79 ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O, 80 1 << offset); 81 if (ret < 0) 82 return ret; 83 84 /* Don't have an atomic direction/value setup */ 85 wm8350_gpio_set(chip, offset, value); 86 87 return 0; 88 } 89 90 static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset) 91 { 92 struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip); 93 struct wm8350 *wm8350 = wm8350_gpio->wm8350; 94 95 if (!wm8350->irq_base) 96 return -EINVAL; 97 98 return wm8350->irq_base + WM8350_IRQ_GPIO(offset); 99 } 100 101 static struct gpio_chip template_chip = { 102 .label = "wm8350", 103 .owner = THIS_MODULE, 104 .direction_input = wm8350_gpio_direction_in, 105 .get = wm8350_gpio_get, 106 .direction_output = wm8350_gpio_direction_out, 107 .set = wm8350_gpio_set, 108 .to_irq = wm8350_gpio_to_irq, 109 .can_sleep = 1, 110 }; 111 112 static int wm8350_gpio_probe(struct platform_device *pdev) 113 { 114 struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent); 115 struct wm8350_platform_data *pdata = wm8350->dev->platform_data; 116 struct wm8350_gpio_data *wm8350_gpio; 117 int ret; 118 119 wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio), 120 GFP_KERNEL); 121 if (wm8350_gpio == NULL) 122 return -ENOMEM; 123 124 wm8350_gpio->wm8350 = wm8350; 125 wm8350_gpio->gpio_chip = template_chip; 126 wm8350_gpio->gpio_chip.ngpio = 13; 127 wm8350_gpio->gpio_chip.dev = &pdev->dev; 128 if (pdata && pdata->gpio_base) 129 wm8350_gpio->gpio_chip.base = pdata->gpio_base; 130 else 131 wm8350_gpio->gpio_chip.base = -1; 132 133 ret = gpiochip_add(&wm8350_gpio->gpio_chip); 134 if (ret < 0) { 135 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret); 136 return ret; 137 } 138 139 platform_set_drvdata(pdev, wm8350_gpio); 140 141 return ret; 142 } 143 144 static int wm8350_gpio_remove(struct platform_device *pdev) 145 { 146 struct wm8350_gpio_data *wm8350_gpio = platform_get_drvdata(pdev); 147 148 return gpiochip_remove(&wm8350_gpio->gpio_chip); 149 } 150 151 static struct platform_driver wm8350_gpio_driver = { 152 .driver.name = "wm8350-gpio", 153 .driver.owner = THIS_MODULE, 154 .probe = wm8350_gpio_probe, 155 .remove = wm8350_gpio_remove, 156 }; 157 158 static int __init wm8350_gpio_init(void) 159 { 160 return platform_driver_register(&wm8350_gpio_driver); 161 } 162 subsys_initcall(wm8350_gpio_init); 163 164 static void __exit wm8350_gpio_exit(void) 165 { 166 platform_driver_unregister(&wm8350_gpio_driver); 167 } 168 module_exit(wm8350_gpio_exit); 169 170 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 171 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs"); 172 MODULE_LICENSE("GPL"); 173 MODULE_ALIAS("platform:wm8350-gpio"); 174