LXR linux/drivers/input/misc/da9052

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * ON pin driver for Dialog DA9052 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#include <linux/workqueue.h>
  14
  15#include <linux/mfd/da9052/da9052.h>
  16#include <linux/mfd/da9052/reg.h>
  17
  18struct da9052_onkey {
  19        struct da9052 *da9052;
  20        struct input_dev *input;
  21        struct delayed_work work;
  22};
  23
  24static void da9052_onkey_query(struct da9052_onkey *onkey)
  25{
  26        int ret;
  27
  28        ret = da9052_reg_read(onkey->da9052, DA9052_STATUS_A_REG);
  29        if (ret < 0) {
  30                dev_err(onkey->da9052->dev,
  31                        "Failed to read onkey event err=%d\n", ret);
  32        } else {
  33                /*
  34                 * Since interrupt for deassertion of ONKEY pin is not
  35                 * generated, onkey event state determines the onkey
  36                 * button state.
  37                 */
  38                bool pressed = !(ret & DA9052_STATUSA_NONKEY);
  39
  40                input_report_key(onkey->input, KEY_POWER, pressed);
  41                input_sync(onkey->input);
  42
  43                /*
  44                 * Interrupt is generated only when the ONKEY pin
  45                 * is asserted.  Hence the deassertion of the pin
  46                 * is simulated through work queue.
  47                 */
  48                if (pressed)
  49                        schedule_delayed_work(&onkey->work,
  50                                                msecs_to_jiffies(50));
  51        }
  52}
  53
  54static void da9052_onkey_work(struct work_struct *work)
  55{
  56        struct da9052_onkey *onkey = container_of(work, struct da9052_onkey,
  57                                                  work.work);
  58
  59        da9052_onkey_query(onkey);
  60}
  61
  62static irqreturn_t da9052_onkey_irq(int irq, void *data)
  63{
  64        struct da9052_onkey *onkey = data;
  65
  66        da9052_onkey_query(onkey);
  67
  68        return IRQ_HANDLED;
  69}
  70
  71static int da9052_onkey_probe(struct platform_device *pdev)
  72{
  73        struct da9052 *da9052 = dev_get_drvdata(pdev->dev.parent);
  74        struct da9052_onkey *onkey;
  75        struct input_dev *input_dev;
  76        int error;
  77
  78        if (!da9052) {
  79                dev_err(&pdev->dev, "Failed to get the driver's data\n");
  80                return -EINVAL;
  81        }
  82
  83        onkey = kzalloc(sizeof(*onkey), GFP_KERNEL);
  84        input_dev = input_allocate_device();
  85        if (!onkey || !input_dev) {
  86                dev_err(&pdev->dev, "Failed to allocate memory\n");
  87                error = -ENOMEM;
  88                goto err_free_mem;
  89        }
  90
  91        onkey->input = input_dev;
  92        onkey->da9052 = da9052;
  93        INIT_DELAYED_WORK(&onkey->work, da9052_onkey_work);
  94
  95        input_dev->name = "da9052-onkey";
  96        input_dev->phys = "da9052-onkey/input0";
  97        input_dev->dev.parent = &pdev->dev;
  98
  99        input_dev->evbit[0] = BIT_MASK(EV_KEY);
 100        __set_bit(KEY_POWER, input_dev->keybit);
 101
 102        error = da9052_request_irq(onkey->da9052, DA9052_IRQ_NONKEY, "ONKEY",
 103                            da9052_onkey_irq, onkey);
 104        if (error < 0) {
 105                dev_err(onkey->da9052->dev,
 106                        "Failed to register ONKEY IRQ: %d\n", error);
 107                goto err_free_mem;
 108        }
 109
 110        error = input_register_device(onkey->input);
 111        if (error) {
 112                dev_err(&pdev->dev, "Unable to register input device, %d\n",
 113                        error);
 114                goto err_free_irq;
 115        }
 116
 117        platform_set_drvdata(pdev, onkey);
 118        return 0;
 119
 120err_free_irq:
 121        da9052_free_irq(onkey->da9052, DA9052_IRQ_NONKEY, onkey);
 122        cancel_delayed_work_sync(&onkey->work);
 123err_free_mem:
 124        input_free_device(input_dev);
 125        kfree(onkey);
 126
 127        return error;
 128}
 129
 130static int da9052_onkey_remove(struct platform_device *pdev)
 131{
 132        struct da9052_onkey *onkey = platform_get_drvdata(pdev);
 133
 134        da9052_free_irq(onkey->da9052, DA9052_IRQ_NONKEY, onkey);
 135        cancel_delayed_work_sync(&onkey->work);
 136
 137        input_unregister_device(onkey->input);
 138        kfree(onkey);
 139
 140        return 0;
 141}
 142
 143static struct platform_driver da9052_onkey_driver = {
 144        .probe  = da9052_onkey_probe,
 145        .remove = da9052_onkey_remove,
 146        .driver = {
 147                .name   = "da9052-onkey",
 148        },
 149};
 150module_platform_driver(da9052_onkey_driver);
 151
 152MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 153MODULE_DESCRIPTION("Onkey driver for DA9052");
 154MODULE_LICENSE("GPL");
 155MODULE_ALIAS("platform:da9052-onkey");
 156