sound/drivers/pcsp/pcsp_input.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  PC Speaker beeper driver for Linux
   4  *
   5  *  Copyright (c) 2002 Vojtech Pavlik
   6  *  Copyright (c) 1992 Orest Zborowski
   7  */
   8
   9
  10 #include <linux/init.h>
  11 #include <linux/input.h>
  12 #include <linux/io.h>
  13 #include "pcsp.h"
  14 #include "pcsp_input.h"
  15
  16 static void pcspkr_do_sound(unsigned int count)
  17 {
  18         unsigned long flags;
  19
  20         raw_spin_lock_irqsave(&i8253_lock, flags);
  21
  22         if (count) {
  23                 /* set command for counter 2, 2 byte write */
  24                 outb_p(0xB6, 0x43);
  25                 /* select desired HZ */
  26                 outb_p(count & 0xff, 0x42);
  27                 outb((count >> 8) & 0xff, 0x42);
  28                 /* enable counter 2 */
  29                 outb_p(inb_p(0x61) | 3, 0x61);
  30         } else {
  31                 /* disable counter 2 */
  32                 outb(inb_p(0x61) & 0xFC, 0x61);
  33         }
  34
  35         raw_spin_unlock_irqrestore(&i8253_lock, flags);
  36 }
  37
  38 void pcspkr_stop_sound(void)
  39 {
  40         pcspkr_do_sound(0);
  41 }
  42
  43 static int pcspkr_input_event(struct input_dev *dev, unsigned int type,
  44                               unsigned int code, int value)
  45 {
  46         unsigned int count = 0;
  47
  48         if (atomic_read(&pcsp_chip.timer_active) || !pcsp_chip.pcspkr)
  49                 return 0;
  50
  51         switch (type) {
  52         case EV_SND:
  53                 switch (code) {
  54                 case SND_BELL:
  55                         if (value)
  56                                 value = 1000;
  57                         break;
  58                 case SND_TONE:
  59                         break;
  60                 default:
  61                         return -1;
  62                 }
  63                 break;
  64
  65         default:
  66                 return -1;
  67         }
  68
  69         if (value > 20 && value < 32767)
  70                 count = PIT_TICK_RATE / value;
  71
  72         pcspkr_do_sound(count);
  73
  74         return 0;
  75 }
  76
  77 int pcspkr_input_init(struct input_dev **rdev, struct device *dev)
  78 {
  79         int err;
  80
  81         struct input_dev *input_dev = input_allocate_device();
  82         if (!input_dev)
  83                 return -ENOMEM;
  84
  85         input_dev->name = "PC Speaker";
  86         input_dev->phys = "isa0061/input0";
  87         input_dev->id.bustype = BUS_ISA;
  88         input_dev->id.vendor = 0x001f;
  89         input_dev->id.product = 0x0001;
  90         input_dev->id.version = 0x0100;
  91         input_dev->dev.parent = dev;
  92
  93         input_dev->evbit[0] = BIT(EV_SND);
  94         input_dev->sndbit[0] = BIT(SND_BELL) | BIT(SND_TONE);
  95         input_dev->event = pcspkr_input_event;
  96
  97         err = input_register_device(input_dev);
  98         if (err) {
  99                 input_free_device(input_dev);
 100                 return err;
 101         }
 102
 103         *rdev = input_dev;
 104         return 0;
 105 }
 106
 107 int pcspkr_input_remove(struct input_dev *dev)
 108 {
 109         pcspkr_stop_sound();
 110         input_unregister_device(dev);   /* this also does kfree() */
 111
 112         return 0;
 113 }