xref: /linux/sound/drivers/pcsp/pcsp_input.c (revision b8d312aa075f33282565467662c4628dae0a2aff)
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 		case SND_TONE:
58 			break;
59 		default:
60 			return -1;
61 		}
62 		break;
63 
64 	default:
65 		return -1;
66 	}
67 
68 	if (value > 20 && value < 32767)
69 		count = PIT_TICK_RATE / value;
70 
71 	pcspkr_do_sound(count);
72 
73 	return 0;
74 }
75 
76 int pcspkr_input_init(struct input_dev **rdev, struct device *dev)
77 {
78 	int err;
79 
80 	struct input_dev *input_dev = input_allocate_device();
81 	if (!input_dev)
82 		return -ENOMEM;
83 
84 	input_dev->name = "PC Speaker";
85 	input_dev->phys = "isa0061/input0";
86 	input_dev->id.bustype = BUS_ISA;
87 	input_dev->id.vendor = 0x001f;
88 	input_dev->id.product = 0x0001;
89 	input_dev->id.version = 0x0100;
90 	input_dev->dev.parent = dev;
91 
92 	input_dev->evbit[0] = BIT(EV_SND);
93 	input_dev->sndbit[0] = BIT(SND_BELL) | BIT(SND_TONE);
94 	input_dev->event = pcspkr_input_event;
95 
96 	err = input_register_device(input_dev);
97 	if (err) {
98 		input_free_device(input_dev);
99 		return err;
100 	}
101 
102 	*rdev = input_dev;
103 	return 0;
104 }
105 
106 int pcspkr_input_remove(struct input_dev *dev)
107 {
108 	pcspkr_stop_sound();
109 	input_unregister_device(dev);	/* this also does kfree() */
110 
111 	return 0;
112 }
113