drivers/input/misc/e3x0-button.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2014, National Instruments Corp. All rights reserved.
   4  *
   5  * Driver for NI Ettus Research USRP E3x0 Button Driver
   6  */
   7
   8 #include <linux/device.h>
   9 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/input.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/of.h>
  15 #include <linux/slab.h>
  16
  17 static irqreturn_t e3x0_button_release_handler(int irq, void *data)
  18 {
  19         struct input_dev *idev = data;
  20
  21         input_report_key(idev, KEY_POWER, 0);
  22         input_sync(idev);
  23
  24         return IRQ_HANDLED;
  25 }
  26
  27 static irqreturn_t e3x0_button_press_handler(int irq, void *data)
  28 {
  29         struct input_dev *idev = data;
  30
  31         input_report_key(idev, KEY_POWER, 1);
  32         pm_wakeup_event(idev->dev.parent, 0);
  33         input_sync(idev);
  34
  35         return IRQ_HANDLED;
  36 }
  37
  38 static int __maybe_unused e3x0_button_suspend(struct device *dev)
  39 {
  40         struct platform_device *pdev = to_platform_device(dev);
  41
  42         if (device_may_wakeup(dev))
  43                 enable_irq_wake(platform_get_irq_byname(pdev, "press"));
  44
  45         return 0;
  46 }
  47
  48 static int __maybe_unused e3x0_button_resume(struct device *dev)
  49 {
  50         struct platform_device *pdev = to_platform_device(dev);
  51
  52         if (device_may_wakeup(dev))
  53                 disable_irq_wake(platform_get_irq_byname(pdev, "press"));
  54
  55         return 0;
  56 }
  57
  58 static SIMPLE_DEV_PM_OPS(e3x0_button_pm_ops,
  59                          e3x0_button_suspend, e3x0_button_resume);
  60
  61 static int e3x0_button_probe(struct platform_device *pdev)
  62 {
  63         struct input_dev *input;
  64         int irq_press, irq_release;
  65         int error;
  66
  67         irq_press = platform_get_irq_byname(pdev, "press");
  68         if (irq_press < 0)
  69                 return irq_press;
  70
  71         irq_release = platform_get_irq_byname(pdev, "release");
  72         if (irq_release < 0)
  73                 return irq_release;
  74
  75         input = devm_input_allocate_device(&pdev->dev);
  76         if (!input)
  77                 return -ENOMEM;
  78
  79         input->name = "NI Ettus Research USRP E3x0 Button Driver";
  80         input->phys = "e3x0_button/input0";
  81         input->dev.parent = &pdev->dev;
  82
  83         input_set_capability(input, EV_KEY, KEY_POWER);
  84
  85         error = devm_request_irq(&pdev->dev, irq_press,
  86                                  e3x0_button_press_handler, 0,
  87                                  "e3x0-button", input);
  88         if (error) {
  89                 dev_err(&pdev->dev, "Failed to request 'press' IRQ#%d: %d\n",
  90                         irq_press, error);
  91                 return error;
  92         }
  93
  94         error = devm_request_irq(&pdev->dev, irq_release,
  95                                  e3x0_button_release_handler, 0,
  96                                  "e3x0-button", input);
  97         if (error) {
  98                 dev_err(&pdev->dev, "Failed to request 'release' IRQ#%d: %d\n",
  99                         irq_release, error);
 100                 return error;
 101         }
 102
 103         error = input_register_device(input);
 104         if (error) {
 105                 dev_err(&pdev->dev, "Can't register input device: %d\n", error);
 106                 return error;
 107         }
 108
 109         device_init_wakeup(&pdev->dev, 1);
 110         return 0;
 111 }
 112
 113 #ifdef CONFIG_OF
 114 static const struct of_device_id e3x0_button_match[] = {
 115         { .compatible = "ettus,e3x0-button", },
 116         { }
 117 };
 118 MODULE_DEVICE_TABLE(of, e3x0_button_match);
 119 #endif
 120
 121 static struct platform_driver e3x0_button_driver = {
 122         .driver         = {
 123                 .name   = "e3x0-button",
 124                 .of_match_table = of_match_ptr(e3x0_button_match),
 125                 .pm     = &e3x0_button_pm_ops,
 126         },
 127         .probe          = e3x0_button_probe,
 128 };
 129
 130 module_platform_driver(e3x0_button_driver);
 131
 132 MODULE_LICENSE("GPL v2");
 133 MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>");
 134 MODULE_DESCRIPTION("NI Ettus Research USRP E3x0 Button driver");
 135 MODULE_ALIAS("platform:e3x0-button");