drivers/input/misc/da9055_onkey.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * ON pin driver for Dialog DA9055 PMICs
   4  *
   5  * Copyright(c) 2012 Dialog Semiconductor Ltd.
   6  *
   7  * Author: David Dajun Chen <dchen@diasemi.com>
   8  */
   9
  10 #include <linux/input.h>
  11 #include <linux/module.h>
  12 #include <linux/platform_device.h>
  13
  14 #include <linux/mfd/da9055/core.h>
  15 #include <linux/mfd/da9055/reg.h>
  16
  17 struct da9055_onkey {
  18         struct da9055 *da9055;
  19         struct input_dev *input;
  20         struct delayed_work work;
  21 };
  22
  23 static void da9055_onkey_query(struct da9055_onkey *onkey)
  24 {
  25         int key_stat;
  26
  27         key_stat = da9055_reg_read(onkey->da9055, DA9055_REG_STATUS_A);
  28         if (key_stat < 0) {
  29                 dev_err(onkey->da9055->dev,
  30                         "Failed to read onkey event %d\n", key_stat);
  31         } else {
  32                 key_stat &= DA9055_NOKEY_STS;
  33                 /*
  34                  * Onkey status bit is cleared when onkey button is released.
  35                  */
  36                 if (!key_stat) {
  37                         input_report_key(onkey->input, KEY_POWER, 0);
  38                         input_sync(onkey->input);
  39                 }
  40         }
  41
  42         /*
  43          * Interrupt is generated only when the ONKEY pin is asserted.
  44          * Hence the deassertion of the pin is simulated through work queue.
  45          */
  46         if (key_stat)
  47                 schedule_delayed_work(&onkey->work, msecs_to_jiffies(10));
  48
  49 }
  50
  51 static void da9055_onkey_work(struct work_struct *work)
  52 {
  53         struct da9055_onkey *onkey = container_of(work, struct da9055_onkey,
  54                                                   work.work);
  55
  56         da9055_onkey_query(onkey);
  57 }
  58
  59 static irqreturn_t da9055_onkey_irq(int irq, void *data)
  60 {
  61         struct da9055_onkey *onkey = data;
  62
  63         input_report_key(onkey->input, KEY_POWER, 1);
  64         input_sync(onkey->input);
  65
  66         da9055_onkey_query(onkey);
  67
  68         return IRQ_HANDLED;
  69 }
  70
  71 static int da9055_onkey_probe(struct platform_device *pdev)
  72 {
  73         struct da9055 *da9055 = dev_get_drvdata(pdev->dev.parent);
  74         struct da9055_onkey *onkey;
  75         struct input_dev *input_dev;
  76         int irq, err;
  77
  78         irq = platform_get_irq_byname(pdev, "ONKEY");
  79         if (irq < 0) {
  80                 dev_err(&pdev->dev,
  81                         "Failed to get an IRQ for input device, %d\n", irq);
  82                 return -EINVAL;
  83         }
  84
  85         onkey = devm_kzalloc(&pdev->dev, sizeof(*onkey), GFP_KERNEL);
  86         if (!onkey) {
  87                 dev_err(&pdev->dev, "Failed to allocate memory\n");
  88                 return -ENOMEM;
  89         }
  90
  91         input_dev = input_allocate_device();
  92         if (!input_dev) {
  93                 dev_err(&pdev->dev, "Failed to allocate memory\n");
  94                 return -ENOMEM;
  95         }
  96
  97         onkey->input = input_dev;
  98         onkey->da9055 = da9055;
  99         input_dev->name = "da9055-onkey";
 100         input_dev->phys = "da9055-onkey/input0";
 101         input_dev->dev.parent = &pdev->dev;
 102
 103         input_dev->evbit[0] = BIT_MASK(EV_KEY);
 104         __set_bit(KEY_POWER, input_dev->keybit);
 105
 106         INIT_DELAYED_WORK(&onkey->work, da9055_onkey_work);
 107
 108         err = request_threaded_irq(irq, NULL, da9055_onkey_irq,
 109                                    IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 110                                    "ONKEY", onkey);
 111         if (err < 0) {
 112                 dev_err(&pdev->dev,
 113                         "Failed to register ONKEY IRQ %d, error = %d\n",
 114                         irq, err);
 115                 goto err_free_input;
 116         }
 117
 118         err = input_register_device(input_dev);
 119         if (err) {
 120                 dev_err(&pdev->dev, "Unable to register input device, %d\n",
 121                         err);
 122                 goto err_free_irq;
 123         }
 124
 125         platform_set_drvdata(pdev, onkey);
 126
 127         return 0;
 128
 129 err_free_irq:
 130         free_irq(irq, onkey);
 131         cancel_delayed_work_sync(&onkey->work);
 132 err_free_input:
 133         input_free_device(input_dev);
 134
 135         return err;
 136 }
 137
 138 static int da9055_onkey_remove(struct platform_device *pdev)
 139 {
 140         struct da9055_onkey *onkey = platform_get_drvdata(pdev);
 141         int irq = platform_get_irq_byname(pdev, "ONKEY");
 142
 143         irq = regmap_irq_get_virq(onkey->da9055->irq_data, irq);
 144         free_irq(irq, onkey);
 145         cancel_delayed_work_sync(&onkey->work);
 146         input_unregister_device(onkey->input);
 147
 148         return 0;
 149 }
 150
 151 static struct platform_driver da9055_onkey_driver = {
 152         .probe  = da9055_onkey_probe,
 153         .remove = da9055_onkey_remove,
 154         .driver = {
 155                 .name   = "da9055-onkey",
 156         },
 157 };
 158
 159 module_platform_driver(da9055_onkey_driver);
 160
 161 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 162 MODULE_DESCRIPTION("Onkey driver for DA9055");
 163 MODULE_LICENSE("GPL");
 164 MODULE_ALIAS("platform:da9055-onkey");