LXR linux/drivers/input/misc/pcap

   1/*
   2 *  Input driver for PCAP events:
   3 *   * Power key
   4 *   * Headphone button
   5 *
   6 *  Copyright (c) 2008,2009 Ilya Petrov <ilya.muromec@gmail.com>
   7 *
   8 *  This program is free software; you can redistribute it and/or modify
   9 *  it under the terms of the GNU General Public License version 2 as
  10 *  published by the Free Software Foundation.
  11 *
  12 */
  13
  14#include <linux/module.h>
  15#include <linux/init.h>
  16#include <linux/interrupt.h>
  17#include <linux/platform_device.h>
  18#include <linux/input.h>
  19#include <linux/mfd/ezx-pcap.h>
  20#include <linux/slab.h>
  21
  22struct pcap_keys {
  23        struct pcap_chip *pcap;
  24        struct input_dev *input;
  25};
  26
  27/* PCAP2 interrupts us on keypress */
  28static irqreturn_t pcap_keys_handler(int irq, void *_pcap_keys)
  29{
  30        struct pcap_keys *pcap_keys = _pcap_keys;
  31        int pirq = irq_to_pcap(pcap_keys->pcap, irq);
  32        u32 pstat;
  33
  34        ezx_pcap_read(pcap_keys->pcap, PCAP_REG_PSTAT, &pstat);
  35        pstat &= 1 << pirq;
  36
  37        switch (pirq) {
  38        case PCAP_IRQ_ONOFF:
  39                input_report_key(pcap_keys->input, KEY_POWER, !pstat);
  40                break;
  41        case PCAP_IRQ_MIC:
  42                input_report_key(pcap_keys->input, KEY_HP, !pstat);
  43                break;
  44        }
  45
  46        input_sync(pcap_keys->input);
  47
  48        return IRQ_HANDLED;
  49}
  50
  51static int __devinit pcap_keys_probe(struct platform_device *pdev)
  52{
  53        int err = -ENOMEM;
  54        struct pcap_keys *pcap_keys;
  55        struct input_dev *input_dev;
  56
  57        pcap_keys = kmalloc(sizeof(struct pcap_keys), GFP_KERNEL);
  58        if (!pcap_keys)
  59                return err;
  60
  61        pcap_keys->pcap = dev_get_drvdata(pdev->dev.parent);
  62
  63        input_dev = input_allocate_device();
  64        if (!input_dev)
  65                goto fail;
  66
  67        pcap_keys->input = input_dev;
  68
  69        platform_set_drvdata(pdev, pcap_keys);
  70        input_dev->name = pdev->name;
  71        input_dev->phys = "pcap-keys/input0";
  72        input_dev->id.bustype = BUS_HOST;
  73        input_dev->dev.parent = &pdev->dev;
  74
  75        __set_bit(EV_KEY, input_dev->evbit);
  76        __set_bit(KEY_POWER, input_dev->keybit);
  77        __set_bit(KEY_HP, input_dev->keybit);
  78
  79        err = input_register_device(input_dev);
  80        if (err)
  81                goto fail_allocate;
  82
  83        err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
  84                        pcap_keys_handler, 0, "Power key", pcap_keys);
  85        if (err)
  86                goto fail_register;
  87
  88        err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
  89                        pcap_keys_handler, 0, "Headphone button", pcap_keys);
  90        if (err)
  91                goto fail_pwrkey;
  92
  93        return 0;
  94
  95fail_pwrkey:
  96        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
  97fail_register:
  98        input_unregister_device(input_dev);
  99        goto fail;
 100fail_allocate:
 101        input_free_device(input_dev);
 102fail:
 103        kfree(pcap_keys);
 104        return err;
 105}
 106
 107static int __devexit pcap_keys_remove(struct platform_device *pdev)
 108{
 109        struct pcap_keys *pcap_keys = platform_get_drvdata(pdev);
 110
 111        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
 112        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC), pcap_keys);
 113
 114        input_unregister_device(pcap_keys->input);
 115        kfree(pcap_keys);
 116
 117        return 0;
 118}
 119
 120static struct platform_driver pcap_keys_device_driver = {
 121        .probe          = pcap_keys_probe,
 122        .remove         = __devexit_p(pcap_keys_remove),
 123        .driver         = {
 124                .name   = "pcap-keys",
 125                .owner  = THIS_MODULE,
 126        }
 127};
 128
 129static int __init pcap_keys_init(void)
 130{
 131        return platform_driver_register(&pcap_keys_device_driver);
 132};
 133
 134static void __exit pcap_keys_exit(void)
 135{
 136        platform_driver_unregister(&pcap_keys_device_driver);
 137};
 138
 139module_init(pcap_keys_init);
 140module_exit(pcap_keys_exit);
 141
 142MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
 143MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
 144MODULE_LICENSE("GPL");
 145MODULE_ALIAS("platform:pcap_keys");
 146