LXR linux/drivers/input/misc/pcap

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  Input driver for PCAP events:
   4 *   * Power key
   5 *   * Headphone button
   6 *
   7 *  Copyright (c) 2008,2009 Ilya Petrov <ilya.muromec@gmail.com>
   8 */
   9
  10#include <linux/module.h>
  11#include <linux/interrupt.h>
  12#include <linux/platform_device.h>
  13#include <linux/input.h>
  14#include <linux/mfd/ezx-pcap.h>
  15#include <linux/slab.h>
  16
  17struct pcap_keys {
  18        struct pcap_chip *pcap;
  19        struct input_dev *input;
  20};
  21
  22/* PCAP2 interrupts us on keypress */
  23static irqreturn_t pcap_keys_handler(int irq, void *_pcap_keys)
  24{
  25        struct pcap_keys *pcap_keys = _pcap_keys;
  26        int pirq = irq_to_pcap(pcap_keys->pcap, irq);
  27        u32 pstat;
  28
  29        ezx_pcap_read(pcap_keys->pcap, PCAP_REG_PSTAT, &pstat);
  30        pstat &= 1 << pirq;
  31
  32        switch (pirq) {
  33        case PCAP_IRQ_ONOFF:
  34                input_report_key(pcap_keys->input, KEY_POWER, !pstat);
  35                break;
  36        case PCAP_IRQ_MIC:
  37                input_report_key(pcap_keys->input, KEY_HP, !pstat);
  38                break;
  39        }
  40
  41        input_sync(pcap_keys->input);
  42
  43        return IRQ_HANDLED;
  44}
  45
  46static int pcap_keys_probe(struct platform_device *pdev)
  47{
  48        int err = -ENOMEM;
  49        struct pcap_keys *pcap_keys;
  50        struct input_dev *input_dev;
  51
  52        pcap_keys = kmalloc(sizeof(struct pcap_keys), GFP_KERNEL);
  53        if (!pcap_keys)
  54                return err;
  55
  56        pcap_keys->pcap = dev_get_drvdata(pdev->dev.parent);
  57
  58        input_dev = input_allocate_device();
  59        if (!input_dev)
  60                goto fail;
  61
  62        pcap_keys->input = input_dev;
  63
  64        platform_set_drvdata(pdev, pcap_keys);
  65        input_dev->name = pdev->name;
  66        input_dev->phys = "pcap-keys/input0";
  67        input_dev->id.bustype = BUS_HOST;
  68        input_dev->dev.parent = &pdev->dev;
  69
  70        __set_bit(EV_KEY, input_dev->evbit);
  71        __set_bit(KEY_POWER, input_dev->keybit);
  72        __set_bit(KEY_HP, input_dev->keybit);
  73
  74        err = input_register_device(input_dev);
  75        if (err)
  76                goto fail_allocate;
  77
  78        err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF),
  79                        pcap_keys_handler, 0, "Power key", pcap_keys);
  80        if (err)
  81                goto fail_register;
  82
  83        err = request_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC),
  84                        pcap_keys_handler, 0, "Headphone button", pcap_keys);
  85        if (err)
  86                goto fail_pwrkey;
  87
  88        return 0;
  89
  90fail_pwrkey:
  91        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
  92fail_register:
  93        input_unregister_device(input_dev);
  94        goto fail;
  95fail_allocate:
  96        input_free_device(input_dev);
  97fail:
  98        kfree(pcap_keys);
  99        return err;
 100}
 101
 102static int pcap_keys_remove(struct platform_device *pdev)
 103{
 104        struct pcap_keys *pcap_keys = platform_get_drvdata(pdev);
 105
 106        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_ONOFF), pcap_keys);
 107        free_irq(pcap_to_irq(pcap_keys->pcap, PCAP_IRQ_MIC), pcap_keys);
 108
 109        input_unregister_device(pcap_keys->input);
 110        kfree(pcap_keys);
 111
 112        return 0;
 113}
 114
 115static struct platform_driver pcap_keys_device_driver = {
 116        .probe          = pcap_keys_probe,
 117        .remove         = pcap_keys_remove,
 118        .driver         = {
 119                .name   = "pcap-keys",
 120        }
 121};
 122module_platform_driver(pcap_keys_device_driver);
 123
 124MODULE_DESCRIPTION("Motorola PCAP2 input events driver");
 125MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>");
 126MODULE_LICENSE("GPL");
 127MODULE_ALIAS("platform:pcap_keys");
 128