LXR linux/drivers/input/misc/da9055

   1/*
   2 * ON pin driver for Dialog DA9055 PMICs
   3 *
   4 * Copyright(c) 2012 Dialog Semiconductor Ltd.
   5 *
   6 * Author: David Dajun Chen <dchen@diasemi.com>
   7 *
   8 * This program is free software; you can redistribute  it and/or modify it
   9 * under  the terms of  the GNU General  Public License as published by the
  10 * Free Software Foundation;  either version 2 of the  License, or (at your
  11 * option) any later version.
  12 */
  13
  14#include <linux/init.h>
  15#include <linux/input.h>
  16#include <linux/module.h>
  17#include <linux/platform_device.h>
  18
  19#include <linux/mfd/da9055/core.h>
  20#include <linux/mfd/da9055/reg.h>
  21
  22struct da9055_onkey {
  23        struct da9055 *da9055;
  24        struct input_dev *input;
  25        struct delayed_work work;
  26};
  27
  28static void da9055_onkey_query(struct da9055_onkey *onkey)
  29{
  30        int key_stat;
  31
  32        key_stat = da9055_reg_read(onkey->da9055, DA9055_REG_STATUS_A);
  33        if (key_stat < 0) {
  34                dev_err(onkey->da9055->dev,
  35                        "Failed to read onkey event %d\n", key_stat);
  36        } else {
  37                key_stat &= DA9055_NOKEY_STS;
  38                /*
  39                 * Onkey status bit is cleared when onkey button is relased.
  40                 */
  41                if (!key_stat) {
  42                        input_report_key(onkey->input, KEY_POWER, 0);
  43                        input_sync(onkey->input);
  44                }
  45        }
  46
  47        /*
  48         * Interrupt is generated only when the ONKEY pin is asserted.
  49         * Hence the deassertion of the pin is simulated through work queue.
  50         */
  51        if (key_stat)
  52                schedule_delayed_work(&onkey->work, msecs_to_jiffies(10));
  53
  54}
  55
  56static void da9055_onkey_work(struct work_struct *work)
  57{
  58        struct da9055_onkey *onkey = container_of(work, struct da9055_onkey,
  59                                                  work.work);
  60
  61        da9055_onkey_query(onkey);
  62}
  63
  64static irqreturn_t da9055_onkey_irq(int irq, void *data)
  65{
  66        struct da9055_onkey *onkey = data;
  67
  68        input_report_key(onkey->input, KEY_POWER, 1);
  69        input_sync(onkey->input);
  70
  71        da9055_onkey_query(onkey);
  72
  73        return IRQ_HANDLED;
  74}
  75
  76static int da9055_onkey_probe(struct platform_device *pdev)
  77{
  78        struct da9055 *da9055 = dev_get_drvdata(pdev->dev.parent);
  79        struct da9055_onkey *onkey;
  80        struct input_dev *input_dev;
  81        int irq, err;
  82
  83        irq = platform_get_irq_byname(pdev, "ONKEY");
  84        if (irq < 0) {
  85                dev_err(&pdev->dev,
  86                        "Failed to get an IRQ for input device, %d\n", irq);
  87                return -EINVAL;
  88        }
  89
  90        onkey = devm_kzalloc(&pdev->dev, sizeof(*onkey), GFP_KERNEL);
  91        if (!onkey) {
  92                dev_err(&pdev->dev, "Failed to allocate memory\n");
  93                return -ENOMEM;
  94        }
  95
  96        input_dev = input_allocate_device();
  97        if (!input_dev) {
  98                dev_err(&pdev->dev, "Failed to allocate memory\n");
  99                return -ENOMEM;
 100        }
 101
 102        onkey->input = input_dev;
 103        onkey->da9055 = da9055;
 104        input_dev->name = "da9055-onkey";
 105        input_dev->phys = "da9055-onkey/input0";
 106        input_dev->dev.parent = &pdev->dev;
 107
 108        input_dev->evbit[0] = BIT_MASK(EV_KEY);
 109        __set_bit(KEY_POWER, input_dev->keybit);
 110
 111        INIT_DELAYED_WORK(&onkey->work, da9055_onkey_work);
 112
 113        irq = regmap_irq_get_virq(da9055->irq_data, irq);
 114        err = request_threaded_irq(irq, NULL, da9055_onkey_irq,
 115                                   IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 116                                   "ONKEY", onkey);
 117        if (err < 0) {
 118                dev_err(&pdev->dev,
 119                        "Failed to register ONKEY IRQ %d, error = %d\n",
 120                        irq, err);
 121                goto err_free_input;
 122        }
 123
 124        err = input_register_device(input_dev);
 125        if (err) {
 126                dev_err(&pdev->dev, "Unable to register input device, %d\n",
 127                        err);
 128                goto err_free_irq;
 129        }
 130
 131        platform_set_drvdata(pdev, onkey);
 132
 133        return 0;
 134
 135err_free_irq:
 136        free_irq(irq, onkey);
 137        cancel_delayed_work_sync(&onkey->work);
 138err_free_input:
 139        input_free_device(input_dev);
 140
 141        return err;
 142}
 143
 144static int da9055_onkey_remove(struct platform_device *pdev)
 145{
 146        struct da9055_onkey *onkey = platform_get_drvdata(pdev);
 147        int irq = platform_get_irq_byname(pdev, "ONKEY");
 148
 149        irq = regmap_irq_get_virq(onkey->da9055->irq_data, irq);
 150        free_irq(irq, onkey);
 151        cancel_delayed_work_sync(&onkey->work);
 152        input_unregister_device(onkey->input);
 153
 154        return 0;
 155}
 156
 157static struct platform_driver da9055_onkey_driver = {
 158        .probe  = da9055_onkey_probe,
 159        .remove = da9055_onkey_remove,
 160        .driver = {
 161                .name   = "da9055-onkey",
 162                .owner  = THIS_MODULE,
 163        },
 164};
 165
 166module_platform_driver(da9055_onkey_driver);
 167
 168MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 169MODULE_DESCRIPTION("Onkey driver for DA9055");
 170MODULE_LICENSE("GPL");
 171MODULE_ALIAS("platform:da9055-onkey");
 172