]>
Commit | Line | Data |
---|---|---|
be48308a | 1 | /* |
6ba12997 | 2 | * extcon_gpio.c - Single-state GPIO extcon driver based on extcon class |
be48308a MH |
3 | * |
4 | * Copyright (C) 2008 Google, Inc. | |
5 | * Author: Mike Lockwood <lockwood@android.com> | |
6 | * | |
7 | * Modified by MyungJoo Ham <myungjoo.ham@samsung.com> to support extcon | |
8 | * (originally switch class is supported) | |
9 | * | |
10 | * This software is licensed under the terms of the GNU General Public | |
11 | * License version 2, as published by the Free Software Foundation, and | |
12 | * may be copied, distributed, and modified under those terms. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
6ba12997 | 18 | */ |
be48308a | 19 | |
176aa360 | 20 | #include <linux/extcon-provider.h> |
62364357 | 21 | #include <linux/gpio.h> |
de992acb | 22 | #include <linux/gpio/consumer.h> |
be48308a MH |
23 | #include <linux/init.h> |
24 | #include <linux/interrupt.h> | |
62364357 GC |
25 | #include <linux/kernel.h> |
26 | #include <linux/module.h> | |
be48308a MH |
27 | #include <linux/platform_device.h> |
28 | #include <linux/slab.h> | |
be48308a | 29 | #include <linux/workqueue.h> |
be48308a | 30 | |
66afdedf | 31 | /** |
a62300d9 LW |
32 | * struct gpio_extcon_data - A simple GPIO-controlled extcon device state container. |
33 | * @edev: Extcon device. | |
34 | * @irq: Interrupt line for the external connector. | |
35 | * @work: Work fired by the interrupt. | |
36 | * @debounce_jiffies: Number of jiffies to wait for the GPIO to stabilize, from the debounce | |
37 | * value. | |
38 | * @id_gpiod: GPIO descriptor for this external connector. | |
66afdedf LW |
39 | * @extcon_id: The unique id of specific external connector. |
40 | * @gpio: Corresponding GPIO. | |
41 | * @gpio_active_low: Boolean describing whether gpio active state is 1 or 0 | |
42 | * If true, low state of gpio means active. | |
43 | * If false, high state of gpio means active. | |
44 | * @debounce: Debounce time for GPIO IRQ in ms. | |
45 | * @irq_flags: IRQ Flags (e.g., IRQF_TRIGGER_LOW). | |
46 | * @check_on_resume: Boolean describing whether to check the state of gpio | |
47 | * while resuming from sleep. | |
48 | */ | |
be48308a | 49 | struct gpio_extcon_data { |
60cd62d4 | 50 | struct extcon_dev *edev; |
be48308a MH |
51 | int irq; |
52 | struct delayed_work work; | |
53 | unsigned long debounce_jiffies; | |
de992acb | 54 | struct gpio_desc *id_gpiod; |
a62300d9 LW |
55 | unsigned int extcon_id; |
56 | unsigned gpio; | |
57 | bool gpio_active_low; | |
58 | unsigned long debounce; | |
59 | unsigned long irq_flags; | |
60 | bool check_on_resume; | |
be48308a MH |
61 | }; |
62 | ||
63 | static void gpio_extcon_work(struct work_struct *work) | |
64 | { | |
65 | int state; | |
66 | struct gpio_extcon_data *data = | |
67 | container_of(to_delayed_work(work), struct gpio_extcon_data, | |
68 | work); | |
69 | ||
de992acb | 70 | state = gpiod_get_value_cansleep(data->id_gpiod); |
a62300d9 | 71 | if (data->gpio_active_low) |
5bfbdc9c | 72 | state = !state; |
cb9850d0 | 73 | |
a62300d9 | 74 | extcon_set_state_sync(data->edev, data->extcon_id, state); |
be48308a MH |
75 | } |
76 | ||
77 | static irqreturn_t gpio_irq_handler(int irq, void *dev_id) | |
78 | { | |
60f9b9e6 | 79 | struct gpio_extcon_data *data = dev_id; |
be48308a | 80 | |
60f9b9e6 CC |
81 | queue_delayed_work(system_power_efficient_wq, &data->work, |
82 | data->debounce_jiffies); | |
be48308a MH |
83 | return IRQ_HANDLED; |
84 | } | |
85 | ||
de992acb CC |
86 | static int gpio_extcon_init(struct device *dev, struct gpio_extcon_data *data) |
87 | { | |
de992acb CC |
88 | int ret; |
89 | ||
a62300d9 | 90 | ret = devm_gpio_request_one(dev, data->gpio, GPIOF_DIR_IN, |
de992acb CC |
91 | dev_name(dev)); |
92 | if (ret < 0) | |
93 | return ret; | |
94 | ||
a62300d9 | 95 | data->id_gpiod = gpio_to_desc(data->gpio); |
de992acb CC |
96 | if (!data->id_gpiod) |
97 | return -EINVAL; | |
98 | ||
a62300d9 | 99 | if (data->debounce) { |
de992acb | 100 | ret = gpiod_set_debounce(data->id_gpiod, |
a62300d9 | 101 | data->debounce * 1000); |
de992acb CC |
102 | if (ret < 0) |
103 | data->debounce_jiffies = | |
a62300d9 | 104 | msecs_to_jiffies(data->debounce); |
de992acb CC |
105 | } |
106 | ||
107 | data->irq = gpiod_to_irq(data->id_gpiod); | |
108 | if (data->irq < 0) | |
109 | return data->irq; | |
110 | ||
111 | return 0; | |
112 | } | |
113 | ||
44f34fd4 | 114 | static int gpio_extcon_probe(struct platform_device *pdev) |
be48308a | 115 | { |
60f9b9e6 | 116 | struct gpio_extcon_data *data; |
1073514b | 117 | int ret; |
be48308a | 118 | |
60f9b9e6 | 119 | data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data), |
be48308a | 120 | GFP_KERNEL); |
60f9b9e6 | 121 | if (!data) |
be48308a | 122 | return -ENOMEM; |
a62300d9 LW |
123 | |
124 | /* | |
125 | * FIXME: extcon_id represents the unique identifier of external | |
126 | * connectors such as EXTCON_USB, EXTCON_DISP_HDMI and so on. extcon_id | |
127 | * is necessary to register the extcon device. But, it's not yet | |
128 | * developed to get the extcon id from device-tree or others. | |
129 | * On later, it have to be solved. | |
130 | */ | |
131 | if (!data->irq_flags || data->extcon_id > EXTCON_NONE) | |
132 | return -EINVAL; | |
60cd62d4 | 133 | |
de992acb CC |
134 | /* Initialize the gpio */ |
135 | ret = gpio_extcon_init(&pdev->dev, data); | |
4288d9b8 GR |
136 | if (ret < 0) |
137 | return ret; | |
138 | ||
de992acb | 139 | /* Allocate the memory of extcon devie and register extcon device */ |
a62300d9 | 140 | data->edev = devm_extcon_dev_allocate(&pdev->dev, &data->extcon_id); |
de992acb CC |
141 | if (IS_ERR(data->edev)) { |
142 | dev_err(&pdev->dev, "failed to allocate extcon device\n"); | |
143 | return -ENOMEM; | |
338de0ca | 144 | } |
be48308a | 145 | |
60f9b9e6 | 146 | ret = devm_extcon_dev_register(&pdev->dev, data->edev); |
be48308a | 147 | if (ret < 0) |
01eaf245 | 148 | return ret; |
be48308a | 149 | |
60f9b9e6 | 150 | INIT_DELAYED_WORK(&data->work, gpio_extcon_work); |
be48308a | 151 | |
de992acb | 152 | /* |
b51b3870 | 153 | * Request the interrupt of gpio to detect whether external connector |
de992acb CC |
154 | * is attached or detached. |
155 | */ | |
60f9b9e6 | 156 | ret = devm_request_any_context_irq(&pdev->dev, data->irq, |
a62300d9 | 157 | gpio_irq_handler, data->irq_flags, |
60f9b9e6 | 158 | pdev->name, data); |
be48308a | 159 | if (ret < 0) |
d92c2f12 | 160 | return ret; |
be48308a | 161 | |
60f9b9e6 | 162 | platform_set_drvdata(pdev, data); |
be48308a | 163 | /* Perform initial detection */ |
60f9b9e6 | 164 | gpio_extcon_work(&data->work.work); |
be48308a MH |
165 | |
166 | return 0; | |
be48308a MH |
167 | } |
168 | ||
93ed0327 | 169 | static int gpio_extcon_remove(struct platform_device *pdev) |
be48308a | 170 | { |
60f9b9e6 | 171 | struct gpio_extcon_data *data = platform_get_drvdata(pdev); |
be48308a | 172 | |
60f9b9e6 | 173 | cancel_delayed_work_sync(&data->work); |
be48308a MH |
174 | |
175 | return 0; | |
176 | } | |
177 | ||
6544dfa5 RY |
178 | #ifdef CONFIG_PM_SLEEP |
179 | static int gpio_extcon_resume(struct device *dev) | |
180 | { | |
60f9b9e6 | 181 | struct gpio_extcon_data *data; |
6544dfa5 | 182 | |
60f9b9e6 | 183 | data = dev_get_drvdata(dev); |
a62300d9 | 184 | if (data->check_on_resume) |
6544dfa5 | 185 | queue_delayed_work(system_power_efficient_wq, |
60f9b9e6 | 186 | &data->work, data->debounce_jiffies); |
6544dfa5 RY |
187 | |
188 | return 0; | |
189 | } | |
190 | #endif | |
191 | ||
3cc731d9 | 192 | static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops, NULL, gpio_extcon_resume); |
6544dfa5 | 193 | |
2878bda8 | 194 | static struct platform_driver gpio_extcon_driver = { |
be48308a | 195 | .probe = gpio_extcon_probe, |
5f7e2228 | 196 | .remove = gpio_extcon_remove, |
be48308a MH |
197 | .driver = { |
198 | .name = "extcon-gpio", | |
6544dfa5 | 199 | .pm = &gpio_extcon_pm_ops, |
be48308a MH |
200 | }, |
201 | }; | |
202 | ||
2878bda8 | 203 | module_platform_driver(gpio_extcon_driver); |
be48308a MH |
204 | |
205 | MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>"); | |
206 | MODULE_DESCRIPTION("GPIO extcon driver"); | |
207 | MODULE_LICENSE("GPL"); |