Commit | Line | Data |
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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> |
de992acb | 21 | #include <linux/gpio/consumer.h> |
be48308a MH |
22 | #include <linux/init.h> |
23 | #include <linux/interrupt.h> | |
62364357 GC |
24 | #include <linux/kernel.h> |
25 | #include <linux/module.h> | |
be48308a MH |
26 | #include <linux/platform_device.h> |
27 | #include <linux/slab.h> | |
be48308a | 28 | #include <linux/workqueue.h> |
be48308a | 29 | |
66afdedf | 30 | /** |
a62300d9 LW |
31 | * struct gpio_extcon_data - A simple GPIO-controlled extcon device state container. |
32 | * @edev: Extcon device. | |
33 | * @irq: Interrupt line for the external connector. | |
34 | * @work: Work fired by the interrupt. | |
35 | * @debounce_jiffies: Number of jiffies to wait for the GPIO to stabilize, from the debounce | |
36 | * value. | |
d368e7de | 37 | * @gpiod: GPIO descriptor for this external connector. |
66afdedf | 38 | * @extcon_id: The unique id of specific external connector. |
66afdedf LW |
39 | * @debounce: Debounce time for GPIO IRQ in ms. |
40 | * @irq_flags: IRQ Flags (e.g., IRQF_TRIGGER_LOW). | |
41 | * @check_on_resume: Boolean describing whether to check the state of gpio | |
42 | * while resuming from sleep. | |
43 | */ | |
be48308a | 44 | struct gpio_extcon_data { |
60cd62d4 | 45 | struct extcon_dev *edev; |
be48308a MH |
46 | int irq; |
47 | struct delayed_work work; | |
48 | unsigned long debounce_jiffies; | |
d368e7de | 49 | struct gpio_desc *gpiod; |
a62300d9 | 50 | unsigned int extcon_id; |
a62300d9 LW |
51 | unsigned long debounce; |
52 | unsigned long irq_flags; | |
53 | bool check_on_resume; | |
be48308a MH |
54 | }; |
55 | ||
56 | static void gpio_extcon_work(struct work_struct *work) | |
57 | { | |
58 | int state; | |
59 | struct gpio_extcon_data *data = | |
60 | container_of(to_delayed_work(work), struct gpio_extcon_data, | |
61 | work); | |
62 | ||
d368e7de | 63 | state = gpiod_get_value_cansleep(data->gpiod); |
a62300d9 | 64 | extcon_set_state_sync(data->edev, data->extcon_id, state); |
be48308a MH |
65 | } |
66 | ||
67 | static irqreturn_t gpio_irq_handler(int irq, void *dev_id) | |
68 | { | |
60f9b9e6 | 69 | struct gpio_extcon_data *data = dev_id; |
be48308a | 70 | |
60f9b9e6 CC |
71 | queue_delayed_work(system_power_efficient_wq, &data->work, |
72 | data->debounce_jiffies); | |
be48308a MH |
73 | return IRQ_HANDLED; |
74 | } | |
75 | ||
44f34fd4 | 76 | static int gpio_extcon_probe(struct platform_device *pdev) |
be48308a | 77 | { |
60f9b9e6 | 78 | struct gpio_extcon_data *data; |
d368e7de | 79 | struct device *dev = &pdev->dev; |
1073514b | 80 | int ret; |
be48308a | 81 | |
d368e7de | 82 | data = devm_kzalloc(dev, sizeof(struct gpio_extcon_data), GFP_KERNEL); |
60f9b9e6 | 83 | if (!data) |
be48308a | 84 | return -ENOMEM; |
a62300d9 LW |
85 | |
86 | /* | |
87 | * FIXME: extcon_id represents the unique identifier of external | |
88 | * connectors such as EXTCON_USB, EXTCON_DISP_HDMI and so on. extcon_id | |
89 | * is necessary to register the extcon device. But, it's not yet | |
90 | * developed to get the extcon id from device-tree or others. | |
91 | * On later, it have to be solved. | |
92 | */ | |
93 | if (!data->irq_flags || data->extcon_id > EXTCON_NONE) | |
94 | return -EINVAL; | |
60cd62d4 | 95 | |
d368e7de LW |
96 | data->gpiod = devm_gpiod_get(dev, "extcon", GPIOD_IN); |
97 | if (IS_ERR(data->gpiod)) | |
98 | return PTR_ERR(data->gpiod); | |
99 | data->irq = gpiod_to_irq(data->gpiod); | |
100 | if (data->irq <= 0) | |
101 | return data->irq; | |
4288d9b8 | 102 | |
de992acb | 103 | /* Allocate the memory of extcon devie and register extcon device */ |
d368e7de | 104 | data->edev = devm_extcon_dev_allocate(dev, &data->extcon_id); |
de992acb | 105 | if (IS_ERR(data->edev)) { |
d368e7de | 106 | dev_err(dev, "failed to allocate extcon device\n"); |
de992acb | 107 | return -ENOMEM; |
338de0ca | 108 | } |
be48308a | 109 | |
d368e7de | 110 | ret = devm_extcon_dev_register(dev, data->edev); |
be48308a | 111 | if (ret < 0) |
01eaf245 | 112 | return ret; |
be48308a | 113 | |
60f9b9e6 | 114 | INIT_DELAYED_WORK(&data->work, gpio_extcon_work); |
be48308a | 115 | |
de992acb | 116 | /* |
b51b3870 | 117 | * Request the interrupt of gpio to detect whether external connector |
de992acb CC |
118 | * is attached or detached. |
119 | */ | |
d368e7de | 120 | ret = devm_request_any_context_irq(dev, data->irq, |
a62300d9 | 121 | gpio_irq_handler, data->irq_flags, |
60f9b9e6 | 122 | pdev->name, data); |
be48308a | 123 | if (ret < 0) |
d92c2f12 | 124 | return ret; |
be48308a | 125 | |
60f9b9e6 | 126 | platform_set_drvdata(pdev, data); |
be48308a | 127 | /* Perform initial detection */ |
60f9b9e6 | 128 | gpio_extcon_work(&data->work.work); |
be48308a MH |
129 | |
130 | return 0; | |
be48308a MH |
131 | } |
132 | ||
93ed0327 | 133 | static int gpio_extcon_remove(struct platform_device *pdev) |
be48308a | 134 | { |
60f9b9e6 | 135 | struct gpio_extcon_data *data = platform_get_drvdata(pdev); |
be48308a | 136 | |
60f9b9e6 | 137 | cancel_delayed_work_sync(&data->work); |
be48308a MH |
138 | |
139 | return 0; | |
140 | } | |
141 | ||
6544dfa5 RY |
142 | #ifdef CONFIG_PM_SLEEP |
143 | static int gpio_extcon_resume(struct device *dev) | |
144 | { | |
60f9b9e6 | 145 | struct gpio_extcon_data *data; |
6544dfa5 | 146 | |
60f9b9e6 | 147 | data = dev_get_drvdata(dev); |
a62300d9 | 148 | if (data->check_on_resume) |
6544dfa5 | 149 | queue_delayed_work(system_power_efficient_wq, |
60f9b9e6 | 150 | &data->work, data->debounce_jiffies); |
6544dfa5 RY |
151 | |
152 | return 0; | |
153 | } | |
154 | #endif | |
155 | ||
3cc731d9 | 156 | static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops, NULL, gpio_extcon_resume); |
6544dfa5 | 157 | |
2878bda8 | 158 | static struct platform_driver gpio_extcon_driver = { |
be48308a | 159 | .probe = gpio_extcon_probe, |
5f7e2228 | 160 | .remove = gpio_extcon_remove, |
be48308a MH |
161 | .driver = { |
162 | .name = "extcon-gpio", | |
6544dfa5 | 163 | .pm = &gpio_extcon_pm_ops, |
be48308a MH |
164 | }, |
165 | }; | |
166 | ||
2878bda8 | 167 | module_platform_driver(gpio_extcon_driver); |
be48308a MH |
168 | |
169 | MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>"); | |
170 | MODULE_DESCRIPTION("GPIO extcon driver"); | |
171 | MODULE_LICENSE("GPL"); |