Version:  2.0.40 2.2.26 2.4.37 2.6.39 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15

Linux/drivers/input/misc/gpio-beeper.c

  1 /*
  2  * Generic GPIO beeper driver
  3  *
  4  * Copyright (C) 2013 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/of_gpio.h>
 15 #include <linux/workqueue.h>
 16 #include <linux/platform_device.h>
 17 
 18 #define BEEPER_MODNAME          "gpio-beeper"
 19 
 20 struct gpio_beeper {
 21         struct work_struct      work;
 22         int                     gpio;
 23         bool                    active_low;
 24         bool                    beeping;
 25 };
 26 
 27 static void gpio_beeper_toggle(struct gpio_beeper *beep, bool on)
 28 {
 29         gpio_set_value_cansleep(beep->gpio, on ^ beep->active_low);
 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         enum of_gpio_flags flags;
 69         struct input_dev *input;
 70         unsigned long gflags;
 71         int err;
 72 
 73         beep = devm_kzalloc(&pdev->dev, sizeof(*beep), GFP_KERNEL);
 74         if (!beep)
 75                 return -ENOMEM;
 76 
 77         beep->gpio = of_get_gpio_flags(pdev->dev.of_node, 0, &flags);
 78         if (!gpio_is_valid(beep->gpio))
 79                 return beep->gpio;
 80 
 81         input = devm_input_allocate_device(&pdev->dev);
 82         if (!input)
 83                 return -ENOMEM;
 84 
 85         INIT_WORK(&beep->work, gpio_beeper_work);
 86 
 87         input->name             = pdev->name;
 88         input->id.bustype       = BUS_HOST;
 89         input->id.vendor        = 0x0001;
 90         input->id.product       = 0x0001;
 91         input->id.version       = 0x0100;
 92         input->close            = gpio_beeper_close;
 93         input->event            = gpio_beeper_event;
 94 
 95         input_set_capability(input, EV_SND, SND_BELL);
 96 
 97         beep->active_low = flags & OF_GPIO_ACTIVE_LOW;
 98         gflags = beep->active_low ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
 99 
100         err = devm_gpio_request_one(&pdev->dev, beep->gpio, gflags, pdev->name);
101         if (err)
102                 return err;
103 
104         input_set_drvdata(input, beep);
105 
106         return input_register_device(input);
107 }
108 
109 static struct of_device_id gpio_beeper_of_match[] = {
110         { .compatible = BEEPER_MODNAME, },
111         { }
112 };
113 MODULE_DEVICE_TABLE(of, gpio_beeper_of_match);
114 
115 static struct platform_driver gpio_beeper_platform_driver = {
116         .driver = {
117                 .name           = BEEPER_MODNAME,
118                 .owner          = THIS_MODULE,
119                 .of_match_table = gpio_beeper_of_match,
120         },
121         .probe  = gpio_beeper_probe,
122 };
123 module_platform_driver(gpio_beeper_platform_driver);
124 
125 MODULE_LICENSE("GPL");
126 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
127 MODULE_DESCRIPTION("Generic GPIO beeper driver");
128 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us