drivers/input/misc/cpcap-pwrbutton.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * CPCAP Power Button Input Driver
   4  *
   5  * Copyright (C) 2017 Sebastian Reichel <sre@kernel.org>
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/kernel.h>
  11 #include <linux/errno.h>
  12 #include <linux/input.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/regmap.h>
  15 #include <linux/of.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/mfd/motorola-cpcap.h>
  18
  19 #define CPCAP_IRQ_ON 23
  20 #define CPCAP_IRQ_ON_BITMASK (1 << (CPCAP_IRQ_ON % 16))
  21
  22 struct cpcap_power_button {
  23         struct regmap *regmap;
  24         struct input_dev *idev;
  25         struct device *dev;
  26 };
  27
  28 static irqreturn_t powerbutton_irq(int irq, void *_button)
  29 {
  30         struct cpcap_power_button *button = _button;
  31         int val;
  32
  33         val = cpcap_sense_virq(button->regmap, irq);
  34         if (val < 0) {
  35                 dev_err(button->dev, "irq read failed: %d", val);
  36                 return IRQ_HANDLED;
  37         }
  38
  39         pm_wakeup_event(button->dev, 0);
  40         input_report_key(button->idev, KEY_POWER, val);
  41         input_sync(button->idev);
  42
  43         return IRQ_HANDLED;
  44 }
  45
  46 static int cpcap_power_button_probe(struct platform_device *pdev)
  47 {
  48         struct cpcap_power_button *button;
  49         int irq;
  50         int err;
  51
  52         irq = platform_get_irq(pdev, 0);
  53         if (irq < 0)
  54                 return irq;
  55
  56         button = devm_kmalloc(&pdev->dev, sizeof(*button), GFP_KERNEL);
  57         if (!button)
  58                 return -ENOMEM;
  59
  60         button->idev = devm_input_allocate_device(&pdev->dev);
  61         if (!button->idev)
  62                 return -ENOMEM;
  63
  64         button->regmap = dev_get_regmap(pdev->dev.parent, NULL);
  65         if (!button->regmap)
  66                 return -ENODEV;
  67
  68         button->dev = &pdev->dev;
  69
  70         button->idev->name = "cpcap-pwrbutton";
  71         button->idev->phys = "cpcap-pwrbutton/input0";
  72         input_set_capability(button->idev, EV_KEY, KEY_POWER);
  73
  74         err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
  75                 powerbutton_irq, IRQF_ONESHOT, "cpcap_pwrbutton", button);
  76         if (err < 0) {
  77                 dev_err(&pdev->dev, "IRQ request failed: %d\n", err);
  78                 return err;
  79         }
  80
  81         err = input_register_device(button->idev);
  82         if (err) {
  83                 dev_err(&pdev->dev, "Input register failed: %d\n", err);
  84                 return err;
  85         }
  86
  87         device_init_wakeup(&pdev->dev, true);
  88
  89         return 0;
  90 }
  91
  92 #ifdef CONFIG_OF
  93 static const struct of_device_id cpcap_pwrbutton_dt_match_table[] = {
  94         { .compatible = "motorola,cpcap-pwrbutton" },
  95         {},
  96 };
  97 MODULE_DEVICE_TABLE(of, cpcap_pwrbutton_dt_match_table);
  98 #endif
  99
 100 static struct platform_driver cpcap_power_button_driver = {
 101         .probe          = cpcap_power_button_probe,
 102         .driver         = {
 103                 .name   = "cpcap-pwrbutton",
 104                 .of_match_table = of_match_ptr(cpcap_pwrbutton_dt_match_table),
 105         },
 106 };
 107 module_platform_driver(cpcap_power_button_driver);
 108
 109 MODULE_ALIAS("platform:cpcap-pwrbutton");
 110 MODULE_DESCRIPTION("CPCAP Power Button");
 111 MODULE_LICENSE("GPL");
 112 MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");