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/interrupt.h>
  16#include <linux/platform_device.h>
  17#include <linux/input.h>
  18#include <linux/mfd/ezx-pcap.h>
  19#include <linux/slab.h>
  20
  21struct pcap_keys {
  22        struct pcap_chip *pcap;
  23        struct input_dev *input;
  24};
  25
  26/* PCAP2 interrupts us on keypress */
  27static irqreturn_t pcap_keys_handler(int irq, void *_pcap_keys)
  28{
  29        struct pcap_keys *pcap_keys = _pcap_keys;
  30        int pirq = irq_to_pcap(pcap_keys->pcap, irq);
  31        u32 pstat;
  32
  33        ezx_pcap_read(pcap_keys->pcap, PCAP_REG_PSTAT, &pstat);
  34        pstat &= 1 << pirq;
  35
  36        switch (pirq) {
  37        case PCAP_IRQ_ONOFF:
  38                input_report_key(pcap_keys->input, KEY_POWER, !pstat);
  39                break;
  40        case PCAP_IRQ_MIC:
  41                input_report_key(pcap_keys->input, KEY_HP, !pstat);
  42                break;
  43        }
  44
  45        input_sync(pcap_keys->input);
  46
  47        return IRQ_HANDLED;
  48}
  49
  50static int pcap_keys_probe(struct platform_device *pdev)
  51{
  52        int err = -ENOMEM;
  53        struct pcap_keys *pcap_keys;
  54        struct input_dev *input_dev;
  55
  56        pcap_keys = kmalloc(sizeof(struct pcap_keys), GFP_KERNEL);
  57        if (!pcap_keys)
  58                return err;
  59
  60        pcap_keys->pcap = dev_get_drvdata(pdev->dev.parent);
  61
  62        input_dev = input_allocate_device();
  63        if (!input_dev)
  64                goto fail;
  65
  66        pcap_keys->input = input_dev;
  67
  68        platform_set_drvdata(pdev, pcap_keys);
  69        input_dev->name = pdev->name;
  70        input_dev->phys = "pcap-keys/input0";
  71        input_dev->id.bustype = BUS_HOST;
  72        input_dev->dev.parent = &pdev->dev;
  73
  74        __set_bit(EV_KEY, input_dev->evbit);
  75        __set_bit(KEY_POWER, input_dev->keybit);
  76        __set_bit(KEY_HP, input_dev->keybit);
  77
  78        err = input_register_device(input_dev);
  79        if (err)
  80                goto fail_allocate;
  81
  82        err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
  83                        pcap_keys_handler, 0, "Power key", pcap_keys);
  84        if (err)
  85                goto fail_register;
  86
  87        err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
  88                        pcap_keys_handler, 0, "Headphone button", pcap_keys);
  89        if (err)
  90                goto fail_pwrkey;
  91
  92        return 0;
  93
  94fail_pwrkey:
  95        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
  96fail_register:
  97        input_unregister_device(input_dev);
  98        goto fail;
  99fail_allocate:
 100        input_free_device(input_dev);
 101fail:
 102        kfree(pcap_keys);
 103        return err;
 104}
 105
 106static int pcap_keys_remove(struct platform_device *pdev)
 107{
 108        struct pcap_keys *pcap_keys = platform_get_drvdata(pdev);
 109
 110        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
 111        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC), pcap_keys);
 112
 113        input_unregister_device(pcap_keys->input);
 114        kfree(pcap_keys);
 115
 116        return 0;
 117}
 118
 119static struct platform_driver pcap_keys_device_driver = {
 120        .probe          = pcap_keys_probe,
 121        .remove         = pcap_keys_remove,
 122        .driver         = {
 123                .name   = "pcap-keys",
 124        }
 125};
 126module_platform_driver(pcap_keys_device_driver);
 127
 128MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
 129MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
 130MODULE_LICENSE("GPL");
 131MODULE_ALIAS("platform:pcap_keys");
 132