1 | /* |
2 | * Generic GPIO beeper driver |
3 | * |
4 | * Copyright (C) 2013-2014 Alexander Shiyan <shc_work@mail.ru> |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify |
7 | * it under the terms of the GNU General Public License as published by |
8 | * the Free Software Foundation; either version 2 of the License, or |
9 | * (at your option) any later version. |
10 | */ |
11 | |
12 | #include <linux/input.h> |
13 | #include <linux/module.h> |
14 | #include <linux/gpio/consumer.h> |
15 | #include <linux/of.h> |
16 | #include <linux/workqueue.h> |
17 | #include <linux/platform_device.h> |
18 | |
19 | #define BEEPER_MODNAME "gpio-beeper" |
20 | |
21 | struct gpio_beeper { |
22 | struct work_struct work; |
23 | struct gpio_desc *desc; |
24 | bool beeping; |
25 | }; |
26 | |
27 | static void gpio_beeper_toggle(struct gpio_beeper *beep, bool on) |
28 | { |
29 | gpiod_set_value_cansleep(beep->desc, on); |
30 | } |
31 | |
32 | static void gpio_beeper_work(struct work_struct *work) |
33 | { |
34 | struct gpio_beeper *beep = container_of(work, struct gpio_beeper, work); |
35 | |
36 | gpio_beeper_toggle(beep, beep->beeping); |
37 | } |
38 | |
39 | static int gpio_beeper_event(struct input_dev *dev, unsigned int type, |
40 | unsigned int code, int value) |
41 | { |
42 | struct gpio_beeper *beep = input_get_drvdata(dev); |
43 | |
44 | if (type != EV_SND || code != SND_BELL) |
45 | return -ENOTSUPP; |
46 | |
47 | if (value < 0) |
48 | return -EINVAL; |
49 | |
50 | beep->beeping = value; |
51 | /* Schedule work to actually turn the beeper on or off */ |
52 | schedule_work(&beep->work); |
53 | |
54 | return 0; |
55 | } |
56 | |
57 | static void gpio_beeper_close(struct input_dev *input) |
58 | { |
59 | struct gpio_beeper *beep = input_get_drvdata(input); |
60 | |
61 | cancel_work_sync(&beep->work); |
62 | gpio_beeper_toggle(beep, false); |
63 | } |
64 | |
65 | static int gpio_beeper_probe(struct platform_device *pdev) |
66 | { |
67 | struct gpio_beeper *beep; |
68 | struct input_dev *input; |
69 | |
70 | beep = devm_kzalloc(&pdev->dev, sizeof(*beep), GFP_KERNEL); |
71 | if (!beep) |
72 | return -ENOMEM; |
73 | |
74 | beep->desc = devm_gpiod_get(&pdev->dev, NULL, GPIOD_OUT_LOW); |
75 | if (IS_ERR(beep->desc)) |
76 | return PTR_ERR(beep->desc); |
77 | |
78 | input = devm_input_allocate_device(&pdev->dev); |
79 | if (!input) |
80 | return -ENOMEM; |
81 | |
82 | INIT_WORK(&beep->work, gpio_beeper_work); |
83 | |
84 | input->name = pdev->name; |
85 | input->id.bustype = BUS_HOST; |
86 | input->id.vendor = 0x0001; |
87 | input->id.product = 0x0001; |
88 | input->id.version = 0x0100; |
89 | input->close = gpio_beeper_close; |
90 | input->event = gpio_beeper_event; |
91 | |
92 | input_set_capability(input, EV_SND, SND_BELL); |
93 | |
94 | input_set_drvdata(input, beep); |
95 | |
96 | return input_register_device(input); |
97 | } |
98 | |
99 | #ifdef CONFIG_OF |
100 | static const struct of_device_id gpio_beeper_of_match[] = { |
101 | { .compatible = BEEPER_MODNAME, }, |
102 | { } |
103 | }; |
104 | MODULE_DEVICE_TABLE(of, gpio_beeper_of_match); |
105 | #endif |
106 | |
107 | static struct platform_driver gpio_beeper_platform_driver = { |
108 | .driver = { |
109 | .name = BEEPER_MODNAME, |
110 | .of_match_table = of_match_ptr(gpio_beeper_of_match), |
111 | }, |
112 | .probe = gpio_beeper_probe, |
113 | }; |
114 | module_platform_driver(gpio_beeper_platform_driver); |
115 | |
116 | MODULE_LICENSE("GPL" ); |
117 | MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>" ); |
118 | MODULE_DESCRIPTION("Generic GPIO beeper driver" ); |
119 | |