1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
|
/*++
Copyright (c) 1991-1993 Microsoft Corporation
Module Name:
pxbeep.c
Abstract:
This module implements the HAL speaker "beep" routines for a Power PC
system.
Author:
Environment:
Kernel mode
Revision History:
--*/
/*
* Copyright (c) 1995 FirePower Systems, Inc.
* DO NOT DISTRIBUTE without permission
*
* $RCSfile: pxbeep.c $
* $Revision: 1.5 $
* $Date: 1996/01/11 07:08:52 $
* $Locker: $
*/
#include "halp.h"
#include "eisa.h"
BOOLEAN
HalMakeBeep(
IN ULONG Frequency
)
/*++
Routine Description:
This function sets the frequency of the speaker, causing it to sound a
tone. The tone will sound until the speaker is explicitly turned off,
so the driver is responsible for controlling the duration of the tone.
Arguments:
Frequency - Supplies the frequency of the desired tone. A frequency of
0 means the speaker should be shut off.
Return Value:
TRUE - Operation was successful (frequency within range or zero).
FALSE - Operation was unsuccessful (frequency was out of range).
Current tone (if any) is unchanged.
--*/
{
KIRQL OldIrql;
NMI_STATUS NmiStatus;
PEISA_CONTROL controlBase = HalpIoControlBase;
TIMER_CONTROL timerControl;
ULONG newCount;
BOOLEAN Result;
//
// Raise IRQL to dispatch level and acquire the beep spin lock.
//
KeAcquireSpinLock(&HalpBeepLock, &OldIrql);
//
// Stop the speaker.
//
*((PUCHAR)&NmiStatus) = READ_REGISTER_UCHAR(&controlBase->NmiStatus);
NmiStatus.SpeakerGate = 0;
NmiStatus.SpeakerData = 0;
WRITE_REGISTER_UCHAR(&controlBase->NmiStatus, *((PUCHAR)&NmiStatus));
//
// If the specified frequency is zero, then the speaker is to be stopped.
//
if (Frequency == 0) {
Result = TRUE;
} else {
//
// If the new count has a magnitude less than 65,536 (0x10000), then
// set the speaker time to the correct mode. Otherwise, return a value
// of FALSE sinc ethe frequency is out of range.
//
newCount = TIMER_CLOCK_IN / Frequency;
if (newCount >= 0x10000) {
Result = FALSE;
} else {
//
// Set the speaker timer to the correct mode.
//
timerControl.BcdMode = 0;
timerControl.Mode = TM_SQUARE_WAVE;
timerControl.SelectByte = SB_LSB_THEN_MSB;
timerControl.SelectCounter = SELECT_COUNTER_2;
WRITE_REGISTER_UCHAR(&controlBase->CommandMode1, *((PUCHAR) &timerControl));
//
// Set the speaker timer to the correct mode.
//
WRITE_REGISTER_UCHAR(&controlBase->SpeakerTone, (UCHAR)(newCount & 0xff));
WRITE_REGISTER_UCHAR(&controlBase->SpeakerTone, (UCHAR)(newCount >> 8));
//
// Start the speaker.
//
NmiStatus.SpeakerGate = 1;
NmiStatus.SpeakerData = 1;
WRITE_REGISTER_UCHAR(&controlBase->NmiStatus, *((PUCHAR) &NmiStatus));
Result = TRUE;
}
}
//
// Release the beep spin lock and lower IRQL to its previous value.
//
KeReleaseSpinLock(&HalpBeepLock, OldIrql);
return Result;
}
|
