Mark Brown | 2955c30 | 2010-01-29 18:20:30 +0000 | [diff] [blame] | 1 | /* |
| 2 | * wm8994-gpio.c -- gpiolib support for Wolfson WM8994 |
| 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> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 16 | #include <linux/slab.h> |
Mark Brown | 2955c30 | 2010-01-29 18:20:30 +0000 | [diff] [blame] | 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/wm8994/core.h> |
| 24 | #include <linux/mfd/wm8994/pdata.h> |
| 25 | #include <linux/mfd/wm8994/gpio.h> |
| 26 | #include <linux/mfd/wm8994/registers.h> |
| 27 | |
| 28 | struct wm8994_gpio { |
| 29 | struct wm8994 *wm8994; |
| 30 | struct gpio_chip gpio_chip; |
| 31 | }; |
| 32 | |
| 33 | static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip) |
| 34 | { |
| 35 | return container_of(chip, struct wm8994_gpio, gpio_chip); |
| 36 | } |
| 37 | |
| 38 | static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset) |
| 39 | { |
| 40 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); |
| 41 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; |
| 42 | |
| 43 | return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, |
| 44 | WM8994_GPN_DIR, WM8994_GPN_DIR); |
| 45 | } |
| 46 | |
| 47 | static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset) |
| 48 | { |
| 49 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); |
| 50 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; |
| 51 | int ret; |
| 52 | |
| 53 | ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset); |
| 54 | if (ret < 0) |
| 55 | return ret; |
| 56 | |
| 57 | if (ret & WM8994_GPN_LVL) |
| 58 | return 1; |
| 59 | else |
| 60 | return 0; |
| 61 | } |
| 62 | |
| 63 | static int wm8994_gpio_direction_out(struct gpio_chip *chip, |
| 64 | unsigned offset, int value) |
| 65 | { |
| 66 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); |
| 67 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; |
| 68 | |
| 69 | return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, |
| 70 | WM8994_GPN_DIR, 0); |
| 71 | } |
| 72 | |
| 73 | static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value) |
| 74 | { |
| 75 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); |
| 76 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; |
| 77 | |
| 78 | if (value) |
| 79 | value = WM8994_GPN_LVL; |
| 80 | |
| 81 | wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value); |
| 82 | } |
| 83 | |
Mark Brown | ddf438c | 2010-04-02 14:51:59 +0100 | [diff] [blame] | 84 | static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset) |
| 85 | { |
| 86 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); |
| 87 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; |
| 88 | |
| 89 | if (!wm8994->irq_base) |
| 90 | return -EINVAL; |
| 91 | |
| 92 | return wm8994->irq_base + offset; |
| 93 | } |
| 94 | |
| 95 | |
Mark Brown | 2955c30 | 2010-01-29 18:20:30 +0000 | [diff] [blame] | 96 | #ifdef CONFIG_DEBUG_FS |
| 97 | static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
| 98 | { |
| 99 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); |
| 100 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; |
| 101 | int i; |
| 102 | |
| 103 | for (i = 0; i < chip->ngpio; i++) { |
| 104 | int gpio = i + chip->base; |
| 105 | int reg; |
| 106 | const char *label; |
| 107 | |
| 108 | /* We report the GPIO even if it's not requested since |
| 109 | * we're also reporting things like alternate |
| 110 | * functions which apply even when the GPIO is not in |
| 111 | * use as a GPIO. |
| 112 | */ |
| 113 | label = gpiochip_is_requested(chip, i); |
| 114 | if (!label) |
| 115 | label = "Unrequested"; |
| 116 | |
| 117 | seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label); |
| 118 | |
| 119 | reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i); |
| 120 | if (reg < 0) { |
| 121 | dev_err(wm8994->dev, |
| 122 | "GPIO control %d read failed: %d\n", |
| 123 | gpio, reg); |
| 124 | seq_printf(s, "\n"); |
| 125 | continue; |
| 126 | } |
| 127 | |
| 128 | /* No decode yet; note that GPIO2 is special */ |
| 129 | seq_printf(s, "(%x)\n", reg); |
| 130 | } |
| 131 | } |
| 132 | #else |
| 133 | #define wm8994_gpio_dbg_show NULL |
| 134 | #endif |
| 135 | |
| 136 | static struct gpio_chip template_chip = { |
| 137 | .label = "wm8994", |
| 138 | .owner = THIS_MODULE, |
| 139 | .direction_input = wm8994_gpio_direction_in, |
| 140 | .get = wm8994_gpio_get, |
| 141 | .direction_output = wm8994_gpio_direction_out, |
| 142 | .set = wm8994_gpio_set, |
Mark Brown | deb26e9 | 2010-08-17 13:13:37 +0100 | [diff] [blame^] | 143 | .to_irq = wm8994_gpio_to_irq, |
Mark Brown | 2955c30 | 2010-01-29 18:20:30 +0000 | [diff] [blame] | 144 | .dbg_show = wm8994_gpio_dbg_show, |
| 145 | .can_sleep = 1, |
| 146 | }; |
| 147 | |
| 148 | static int __devinit wm8994_gpio_probe(struct platform_device *pdev) |
| 149 | { |
| 150 | struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent); |
| 151 | struct wm8994_pdata *pdata = wm8994->dev->platform_data; |
| 152 | struct wm8994_gpio *wm8994_gpio; |
| 153 | int ret; |
| 154 | |
| 155 | wm8994_gpio = kzalloc(sizeof(*wm8994_gpio), GFP_KERNEL); |
| 156 | if (wm8994_gpio == NULL) |
| 157 | return -ENOMEM; |
| 158 | |
| 159 | wm8994_gpio->wm8994 = wm8994; |
| 160 | wm8994_gpio->gpio_chip = template_chip; |
| 161 | wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX; |
| 162 | wm8994_gpio->gpio_chip.dev = &pdev->dev; |
| 163 | if (pdata && pdata->gpio_base) |
| 164 | wm8994_gpio->gpio_chip.base = pdata->gpio_base; |
| 165 | else |
| 166 | wm8994_gpio->gpio_chip.base = -1; |
| 167 | |
| 168 | ret = gpiochip_add(&wm8994_gpio->gpio_chip); |
| 169 | if (ret < 0) { |
| 170 | dev_err(&pdev->dev, "Could not register gpiochip, %d\n", |
| 171 | ret); |
| 172 | goto err; |
| 173 | } |
| 174 | |
| 175 | platform_set_drvdata(pdev, wm8994_gpio); |
| 176 | |
| 177 | return ret; |
| 178 | |
| 179 | err: |
| 180 | kfree(wm8994_gpio); |
| 181 | return ret; |
| 182 | } |
| 183 | |
| 184 | static int __devexit wm8994_gpio_remove(struct platform_device *pdev) |
| 185 | { |
| 186 | struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev); |
| 187 | int ret; |
| 188 | |
| 189 | ret = gpiochip_remove(&wm8994_gpio->gpio_chip); |
| 190 | if (ret == 0) |
| 191 | kfree(wm8994_gpio); |
| 192 | |
| 193 | return ret; |
| 194 | } |
| 195 | |
| 196 | static struct platform_driver wm8994_gpio_driver = { |
| 197 | .driver.name = "wm8994-gpio", |
| 198 | .driver.owner = THIS_MODULE, |
| 199 | .probe = wm8994_gpio_probe, |
| 200 | .remove = __devexit_p(wm8994_gpio_remove), |
| 201 | }; |
| 202 | |
| 203 | static int __init wm8994_gpio_init(void) |
| 204 | { |
| 205 | return platform_driver_register(&wm8994_gpio_driver); |
| 206 | } |
| 207 | subsys_initcall(wm8994_gpio_init); |
| 208 | |
| 209 | static void __exit wm8994_gpio_exit(void) |
| 210 | { |
| 211 | platform_driver_unregister(&wm8994_gpio_driver); |
| 212 | } |
| 213 | module_exit(wm8994_gpio_exit); |
| 214 | |
| 215 | MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); |
| 216 | MODULE_DESCRIPTION("GPIO interface for WM8994"); |
| 217 | MODULE_LICENSE("GPL"); |
| 218 | MODULE_ALIAS("platform:wm8994-gpio"); |