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
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
/*-
* Copyright (c) 2007 Ariff Abdullah <ariff@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/systm.h>
#ifdef HAVE_KERNEL_OPTION_HEADERS
#include "opt_snd.h"
#endif
#include <dev/sound/unit.h>
/*
* Unit magic allocator for sound driver.
*
* 'u' = Unit of attached soundcards
* 'd' = Device type
* 'c' = Channel number
*
* eg: dsp0.p1 - u=0, d=p, c=1
* dsp1.vp0 - u=1, d=vp, c=0
* dsp0.10 - u=0, d=clone, c=allocated clone (see further explanation)
*
* Maximum unit of soundcards can be tuned through "hw.snd.maxunit", which
* is between SND_UNIT_UMIN (16) and SND_UNIT_UMAX (2048). By design,
* maximum allowable allocated channel is 256, with exception for clone
* devices which doesn't have any notion of channel numbering. The use of
* channel numbering in a clone device is simply to provide uniqueness among
* allocated clones. This also means that the maximum allowable clonable
* device is largely dependant and dynamically tuned depending on
* hw.snd.maxunit.
*/
/* Default width */
static int snd_u_shift = 9; /* 0 - 0x1ff : 512 distinct soundcards */
static int snd_d_shift = 5; /* 0 - 0x1f : 32 distinct device types */
static int snd_c_shift = 10; /* 0 - 0x3ff : 1024 distinct channels
(256 limit "by design",
except for clone devices) */
static int snd_unit_initialized = 0;
#ifdef SND_DIAGNOSTIC
#define SND_UNIT_ASSERT() do { \
if (snd_unit_initialized == 0) \
panic("%s(): Uninitialized sound unit!", __func__); \
} while (0)
#else
#define SND_UNIT_ASSERT() KASSERT(snd_unit_initialized != 0, \
("%s(): Uninitialized sound unit!", \
__func__))
#endif
#define MKMASK(x) ((1 << snd_##x##_shift) - 1)
int
snd_max_u(void)
{
SND_UNIT_ASSERT();
return (MKMASK(u));
}
int
snd_max_d(void)
{
SND_UNIT_ASSERT();
return (MKMASK(d));
}
int
snd_max_c(void)
{
SND_UNIT_ASSERT();
return (MKMASK(c));
}
int
snd_unit2u(int unit)
{
SND_UNIT_ASSERT();
return ((unit >> (snd_c_shift + snd_d_shift)) & MKMASK(u));
}
int
snd_unit2d(int unit)
{
SND_UNIT_ASSERT();
return ((unit >> snd_c_shift) & MKMASK(d));
}
int
snd_unit2c(int unit)
{
SND_UNIT_ASSERT();
return (unit & MKMASK(c));
}
int
snd_u2unit(int u)
{
SND_UNIT_ASSERT();
return ((u & MKMASK(u)) << (snd_c_shift + snd_d_shift));
}
int
snd_d2unit(int d)
{
SND_UNIT_ASSERT();
return ((d & MKMASK(d)) << snd_c_shift);
}
int
snd_c2unit(int c)
{
SND_UNIT_ASSERT();
return (c & MKMASK(c));
}
int
snd_mkunit(int u, int d, int c)
{
SND_UNIT_ASSERT();
return ((c & MKMASK(c)) | ((d & MKMASK(d)) << snd_c_shift) |
((u & MKMASK(u)) << (snd_c_shift + snd_d_shift)));
}
/*
* This *must* be called first before any of the functions above!!!
*/
void
snd_unit_init(void)
{
int i;
if (snd_unit_initialized != 0)
return;
snd_unit_initialized = 1;
if (getenv_int("hw.snd.maxunit", &i) != 0) {
if (i < SND_UNIT_UMIN)
i = SND_UNIT_UMIN;
else if (i > SND_UNIT_UMAX)
i = SND_UNIT_UMAX;
else
i = roundup2(i, 2);
for (snd_u_shift = 0; (i >> (snd_u_shift + 1)) != 0;
snd_u_shift++)
;
/*
* Make room for channels/clones allocation unit
* to fit within 24bit MAXMINOR limit.
*/
snd_c_shift = 24 - snd_u_shift - snd_d_shift;
}
if (bootverbose != 0)
printf("%s() u=0x%08x [%d] d=0x%08x [%d] c=0x%08x [%d]\n",
__func__, SND_U_MASK, snd_max_u() + 1,
SND_D_MASK, snd_max_d() + 1, SND_C_MASK, snd_max_c() + 1);
}
|
