MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 1 | /* |
| 2 | * drivers/extcon/extcon_gpio.c |
| 3 | * |
| 4 | * Single-state GPIO extcon driver based on extcon class |
| 5 | * |
| 6 | * Copyright (C) 2008 Google, Inc. |
| 7 | * Author: Mike Lockwood <lockwood@android.com> |
| 8 | * |
| 9 | * Modified by MyungJoo Ham <myungjoo.ham@samsung.com> to support extcon |
| 10 | * (originally switch class is supported) |
| 11 | * |
| 12 | * This software is licensed under the terms of the GNU General Public |
| 13 | * License version 2, as published by the Free Software Foundation, and |
| 14 | * may be copied, distributed, and modified under those terms. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | */ |
| 22 | |
| 23 | #include <linux/module.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/init.h> |
| 26 | #include <linux/interrupt.h> |
| 27 | #include <linux/platform_device.h> |
| 28 | #include <linux/slab.h> |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 29 | #include <linux/workqueue.h> |
| 30 | #include <linux/gpio.h> |
| 31 | #include <linux/extcon.h> |
Chanwoo Choi | fd11606 | 2013-02-13 18:35:00 +0900 | [diff] [blame] | 32 | #include <linux/extcon/extcon-gpio.h> |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 33 | |
| 34 | struct gpio_extcon_data { |
| 35 | struct extcon_dev edev; |
| 36 | unsigned gpio; |
| 37 | const char *state_on; |
| 38 | const char *state_off; |
| 39 | int irq; |
| 40 | struct delayed_work work; |
| 41 | unsigned long debounce_jiffies; |
| 42 | }; |
| 43 | |
| 44 | static void gpio_extcon_work(struct work_struct *work) |
| 45 | { |
| 46 | int state; |
| 47 | struct gpio_extcon_data *data = |
| 48 | container_of(to_delayed_work(work), struct gpio_extcon_data, |
| 49 | work); |
| 50 | |
| 51 | state = gpio_get_value(data->gpio); |
| 52 | extcon_set_state(&data->edev, state); |
| 53 | } |
| 54 | |
| 55 | static irqreturn_t gpio_irq_handler(int irq, void *dev_id) |
| 56 | { |
| 57 | struct gpio_extcon_data *extcon_data = dev_id; |
| 58 | |
Mark Brown | d0db2e7 | 2013-07-19 18:47:34 +0100 | [diff] [blame] | 59 | queue_delayed_work(system_power_efficient_wq, &extcon_data->work, |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 60 | extcon_data->debounce_jiffies); |
| 61 | return IRQ_HANDLED; |
| 62 | } |
| 63 | |
| 64 | static ssize_t extcon_gpio_print_state(struct extcon_dev *edev, char *buf) |
| 65 | { |
| 66 | struct gpio_extcon_data *extcon_data = |
| 67 | container_of(edev, struct gpio_extcon_data, edev); |
| 68 | const char *state; |
| 69 | if (extcon_get_state(edev)) |
| 70 | state = extcon_data->state_on; |
| 71 | else |
| 72 | state = extcon_data->state_off; |
| 73 | |
| 74 | if (state) |
| 75 | return sprintf(buf, "%s\n", state); |
| 76 | return -EINVAL; |
| 77 | } |
| 78 | |
Bill Pemberton | 44f34fd | 2012-11-19 13:23:21 -0500 | [diff] [blame] | 79 | static int gpio_extcon_probe(struct platform_device *pdev) |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 80 | { |
| 81 | struct gpio_extcon_platform_data *pdata = pdev->dev.platform_data; |
| 82 | struct gpio_extcon_data *extcon_data; |
Guenter Roeck | 1073514 | 2013-08-29 21:29:33 -0700 | [diff] [blame^] | 83 | int ret; |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 84 | |
| 85 | if (!pdata) |
| 86 | return -EBUSY; |
| 87 | if (!pdata->irq_flags) { |
| 88 | dev_err(&pdev->dev, "IRQ flag is not specified.\n"); |
| 89 | return -EINVAL; |
| 90 | } |
| 91 | |
| 92 | extcon_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data), |
| 93 | GFP_KERNEL); |
| 94 | if (!extcon_data) |
| 95 | return -ENOMEM; |
| 96 | |
| 97 | extcon_data->edev.name = pdata->name; |
| 98 | extcon_data->gpio = pdata->gpio; |
| 99 | extcon_data->state_on = pdata->state_on; |
| 100 | extcon_data->state_off = pdata->state_off; |
| 101 | if (pdata->state_on && pdata->state_off) |
| 102 | extcon_data->edev.print_state = extcon_gpio_print_state; |
| 103 | extcon_data->debounce_jiffies = msecs_to_jiffies(pdata->debounce); |
| 104 | |
| 105 | ret = extcon_dev_register(&extcon_data->edev, &pdev->dev); |
| 106 | if (ret < 0) |
Axel Lin | 01eaf24 | 2012-06-16 11:56:24 +0800 | [diff] [blame] | 107 | return ret; |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 108 | |
Axel Lin | 7b7e995 | 2012-07-24 09:26:57 +0800 | [diff] [blame] | 109 | ret = devm_gpio_request_one(&pdev->dev, extcon_data->gpio, GPIOF_DIR_IN, |
| 110 | pdev->name); |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 111 | if (ret < 0) |
Axel Lin | 01eaf24 | 2012-06-16 11:56:24 +0800 | [diff] [blame] | 112 | goto err; |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 113 | |
| 114 | INIT_DELAYED_WORK(&extcon_data->work, gpio_extcon_work); |
| 115 | |
| 116 | extcon_data->irq = gpio_to_irq(extcon_data->gpio); |
| 117 | if (extcon_data->irq < 0) { |
| 118 | ret = extcon_data->irq; |
Axel Lin | 01eaf24 | 2012-06-16 11:56:24 +0800 | [diff] [blame] | 119 | goto err; |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 120 | } |
| 121 | |
| 122 | ret = request_any_context_irq(extcon_data->irq, gpio_irq_handler, |
| 123 | pdata->irq_flags, pdev->name, |
| 124 | extcon_data); |
| 125 | if (ret < 0) |
Axel Lin | 01eaf24 | 2012-06-16 11:56:24 +0800 | [diff] [blame] | 126 | goto err; |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 127 | |
Axel Lin | b945f3f | 2012-06-16 11:55:18 +0800 | [diff] [blame] | 128 | platform_set_drvdata(pdev, extcon_data); |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 129 | /* Perform initial detection */ |
| 130 | gpio_extcon_work(&extcon_data->work.work); |
| 131 | |
| 132 | return 0; |
| 133 | |
Axel Lin | 01eaf24 | 2012-06-16 11:56:24 +0800 | [diff] [blame] | 134 | err: |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 135 | extcon_dev_unregister(&extcon_data->edev); |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 136 | |
| 137 | return ret; |
| 138 | } |
| 139 | |
Bill Pemberton | 93ed032 | 2012-11-19 13:25:49 -0500 | [diff] [blame] | 140 | static int gpio_extcon_remove(struct platform_device *pdev) |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 141 | { |
| 142 | struct gpio_extcon_data *extcon_data = platform_get_drvdata(pdev); |
| 143 | |
| 144 | cancel_delayed_work_sync(&extcon_data->work); |
Axel Lin | b945f3f | 2012-06-16 11:55:18 +0800 | [diff] [blame] | 145 | free_irq(extcon_data->irq, extcon_data); |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 146 | extcon_dev_unregister(&extcon_data->edev); |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 147 | |
| 148 | return 0; |
| 149 | } |
| 150 | |
H Hartley Sweeten | 2878bda | 2012-05-02 15:38:44 -0700 | [diff] [blame] | 151 | static struct platform_driver gpio_extcon_driver = { |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 152 | .probe = gpio_extcon_probe, |
Bill Pemberton | 5f7e222 | 2012-11-19 13:20:06 -0500 | [diff] [blame] | 153 | .remove = gpio_extcon_remove, |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 154 | .driver = { |
| 155 | .name = "extcon-gpio", |
| 156 | .owner = THIS_MODULE, |
| 157 | }, |
| 158 | }; |
| 159 | |
H Hartley Sweeten | 2878bda | 2012-05-02 15:38:44 -0700 | [diff] [blame] | 160 | module_platform_driver(gpio_extcon_driver); |
MyungJoo Ham | be48308 | 2012-04-20 14:16:23 +0900 | [diff] [blame] | 161 | |
| 162 | MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>"); |
| 163 | MODULE_DESCRIPTION("GPIO extcon driver"); |
| 164 | MODULE_LICENSE("GPL"); |