2 * drivers/extcon/extcon_gpio.c
4 * Single-state GPIO extcon driver based on extcon class
6 * Copyright (C) 2008 Google, Inc.
7 * Author: Mike Lockwood <lockwood@android.com>
9 * Modified by MyungJoo Ham <myungjoo.ham@samsung.com> to support extcon
10 * (originally switch class is supported)
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.
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.
23 #include <linux/extcon.h>
24 #include <linux/extcon/extcon-gpio.h>
25 #include <linux/gpio.h>
26 #include <linux/init.h>
27 #include <linux/interrupt.h>
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/platform_device.h>
31 #include <linux/slab.h>
32 #include <linux/workqueue.h>
34 struct gpio_extcon_data
{
35 struct extcon_dev
*edev
;
39 const char *state_off
;
41 struct delayed_work work
;
42 unsigned long debounce_jiffies
;
46 static void gpio_extcon_work(struct work_struct
*work
)
49 struct gpio_extcon_data
*data
=
50 container_of(to_delayed_work(work
), struct gpio_extcon_data
,
53 state
= gpio_get_value(data
->gpio
);
54 if (data
->gpio_active_low
)
56 extcon_set_state(data
->edev
, state
);
59 static irqreturn_t
gpio_irq_handler(int irq
, void *dev_id
)
61 struct gpio_extcon_data
*extcon_data
= dev_id
;
63 queue_delayed_work(system_power_efficient_wq
, &extcon_data
->work
,
64 extcon_data
->debounce_jiffies
);
68 static int gpio_extcon_probe(struct platform_device
*pdev
)
70 struct gpio_extcon_platform_data
*pdata
= dev_get_platdata(&pdev
->dev
);
71 struct gpio_extcon_data
*extcon_data
;
76 if (!pdata
->irq_flags
) {
77 dev_err(&pdev
->dev
, "IRQ flag is not specified.\n");
81 extcon_data
= devm_kzalloc(&pdev
->dev
, sizeof(struct gpio_extcon_data
),
86 extcon_data
->edev
= devm_extcon_dev_allocate(&pdev
->dev
, NULL
);
87 if (IS_ERR(extcon_data
->edev
)) {
88 dev_err(&pdev
->dev
, "failed to allocate extcon device\n");
92 extcon_data
->gpio
= pdata
->gpio
;
93 extcon_data
->gpio_active_low
= pdata
->gpio_active_low
;
94 extcon_data
->state_on
= pdata
->state_on
;
95 extcon_data
->state_off
= pdata
->state_off
;
96 extcon_data
->check_on_resume
= pdata
->check_on_resume
;
98 ret
= devm_gpio_request_one(&pdev
->dev
, extcon_data
->gpio
, GPIOF_DIR_IN
,
103 if (pdata
->debounce
) {
104 ret
= gpio_set_debounce(extcon_data
->gpio
,
105 pdata
->debounce
* 1000);
107 extcon_data
->debounce_jiffies
=
108 msecs_to_jiffies(pdata
->debounce
);
111 ret
= devm_extcon_dev_register(&pdev
->dev
, extcon_data
->edev
);
115 INIT_DELAYED_WORK(&extcon_data
->work
, gpio_extcon_work
);
117 extcon_data
->irq
= gpio_to_irq(extcon_data
->gpio
);
118 if (extcon_data
->irq
< 0)
119 return extcon_data
->irq
;
121 ret
= request_any_context_irq(extcon_data
->irq
, gpio_irq_handler
,
122 pdata
->irq_flags
, pdev
->name
,
127 platform_set_drvdata(pdev
, extcon_data
);
128 /* Perform initial detection */
129 gpio_extcon_work(&extcon_data
->work
.work
);
134 static int gpio_extcon_remove(struct platform_device
*pdev
)
136 struct gpio_extcon_data
*extcon_data
= platform_get_drvdata(pdev
);
138 cancel_delayed_work_sync(&extcon_data
->work
);
139 free_irq(extcon_data
->irq
, extcon_data
);
144 #ifdef CONFIG_PM_SLEEP
145 static int gpio_extcon_resume(struct device
*dev
)
147 struct gpio_extcon_data
*extcon_data
;
149 extcon_data
= dev_get_drvdata(dev
);
150 if (extcon_data
->check_on_resume
)
151 queue_delayed_work(system_power_efficient_wq
,
152 &extcon_data
->work
, extcon_data
->debounce_jiffies
);
158 static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops
, NULL
, gpio_extcon_resume
);
160 static struct platform_driver gpio_extcon_driver
= {
161 .probe
= gpio_extcon_probe
,
162 .remove
= gpio_extcon_remove
,
164 .name
= "extcon-gpio",
165 .pm
= &gpio_extcon_pm_ops
,
169 module_platform_driver(gpio_extcon_driver
);
171 MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
172 MODULE_DESCRIPTION("GPIO extcon driver");
173 MODULE_LICENSE("GPL");