drivers/input/misc/rave-sp-pwrbutton.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Power Button driver for RAVE SP
   4 //
   5 // Copyright (C) 2017 Zodiac Inflight Innovations
   6 //
   7 //
   8
   9 #include <linux/input.h>
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/mfd/rave-sp.h>
  13 #include <linux/platform_device.h>
  14
  15 #define RAVE_SP_EVNT_BUTTON_PRESS       (RAVE_SP_EVNT_BASE + 0x00)
  16
  17 struct rave_sp_power_button {
  18         struct input_dev *idev;
  19         struct notifier_block nb;
  20 };
  21
  22 static int rave_sp_power_button_event(struct notifier_block *nb,
  23                                       unsigned long action, void *data)
  24 {
  25         struct rave_sp_power_button *pb =
  26                 container_of(nb, struct rave_sp_power_button, nb);
  27         const u8 event = rave_sp_action_unpack_event(action);
  28         const u8 value = rave_sp_action_unpack_value(action);
  29         struct input_dev *idev = pb->idev;
  30
  31         if (event == RAVE_SP_EVNT_BUTTON_PRESS) {
  32                 input_report_key(idev, KEY_POWER, value);
  33                 input_sync(idev);
  34
  35                 return NOTIFY_STOP;
  36         }
  37
  38         return NOTIFY_DONE;
  39 }
  40
  41 static int rave_sp_pwrbutton_probe(struct platform_device *pdev)
  42 {
  43         struct device *dev = &pdev->dev;
  44         struct rave_sp_power_button *pb;
  45         struct input_dev *idev;
  46         int error;
  47
  48         pb = devm_kzalloc(dev, sizeof(*pb), GFP_KERNEL);
  49         if (!pb)
  50                 return -ENOMEM;
  51
  52         idev = devm_input_allocate_device(dev);
  53         if (!idev)
  54                 return -ENOMEM;
  55
  56         idev->name = pdev->name;
  57
  58         input_set_capability(idev, EV_KEY, KEY_POWER);
  59
  60         error = input_register_device(idev);
  61         if (error)
  62                 return error;
  63
  64         pb->idev = idev;
  65         pb->nb.notifier_call = rave_sp_power_button_event;
  66         pb->nb.priority = 128;
  67
  68         error = devm_rave_sp_register_event_notifier(dev, &pb->nb);
  69         if (error)
  70                 return error;
  71
  72         return 0;
  73 }
  74
  75 static const struct of_device_id rave_sp_pwrbutton_of_match[] = {
  76         { .compatible = "zii,rave-sp-pwrbutton" },
  77         {}
  78 };
  79
  80 static struct platform_driver rave_sp_pwrbutton_driver = {
  81         .probe = rave_sp_pwrbutton_probe,
  82         .driver = {
  83                 .name = KBUILD_MODNAME,
  84                 .of_match_table = rave_sp_pwrbutton_of_match,
  85         },
  86 };
  87 module_platform_driver(rave_sp_pwrbutton_driver);
  88
  89 MODULE_DEVICE_TABLE(of, rave_sp_pwrbutton_of_match);
  90 MODULE_LICENSE("GPL");
  91 MODULE_AUTHOR("Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>");
  92 MODULE_AUTHOR("Nikita Yushchenko <nikita.yoush@cogentembedded.com>");
  93 MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
  94 MODULE_DESCRIPTION("RAVE SP Power Button driver");