1 /* $NetBSD: audiobell.c,v 1.5 2021/07/21 06:35:44 skrll Exp $ */
2
3 /*
4 * Copyright (c) 1999 Richard Earnshaw
5 * Copyright (c) 2004 Ben Harris
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the RiscBSD team.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: audiobell.c,v 1.5 2021/07/21 06:35:44 skrll Exp $");
35
36 #include <sys/param.h>
37 #include <sys/types.h>
38 #include <sys/audioio.h>
39 #include <sys/conf.h>
40 #include <sys/device.h>
41 #include <sys/malloc.h>
42 #include <sys/systm.h>
43 #include <sys/uio.h>
44
45 #include <dev/audio/audio_if.h>
46 #include <dev/audio/audiovar.h>
47 #include <dev/audio/audiodef.h>
48 #include <dev/audio/audiobellvar.h>
49
50 /*
51 * The hexadecagon is sufficiently close to a sine wave.
52 * Audiobell always outputs this 16 points data but changes its playback
53 * frequency. In addition, audio layer does linear interpolation in the
54 * frequency conversion stage, so the waveform becomes smooth.
55 * When the playback frequency rises (or the device frequency is not enough
56 * high) and one wave cannot be expressed with 16 points, the data is thinned
57 * out by power of two, like 8 points -> 4 points (triangular wave)
58 * -> 2 points (rectangular wave).
59 */
60
61 /* Amplitude. Full scale amplitude is too loud. */
62 #define A(x) ((x) * 0.6)
63
64 /* (sin(2*pi * (x/16)) * 32767 / 100) << 16 */
65 static const int32_t sinewave[] = {
66 A( 0),
67 A( 8217813),
68 A( 15184539),
69 A( 19839556),
70 A( 21474181),
71 A( 19839556),
72 A( 15184539),
73 A( 8217813),
74 A( 0),
75 A( -8217814),
76 A(-15184540),
77 A(-19839557),
78 A(-21474182),
79 A(-19839557),
80 A(-15184540),
81 A( -8217814),
82 };
83 #undef A
84
85 /*
86 * The minimum and the maximum buffer sizes must be a multiple of 32
87 * (32 = countof(sinewave) * sizeof(uint16_t)).
88 */
89 #define MINBUFSIZE (1024)
90 #define MAXBUFSIZE (4096)
91
92 /*
93 * dev is a device_t for the audio device to use.
94 * pitch is the pitch of the bell in Hz,
95 * period is the length in ms,
96 * volume is the amplitude in % of max,
97 * poll is no longer used.
98 */
99 void
audiobell(void * dev,u_int pitch,u_int period,u_int volume,int poll)100 audiobell(void *dev, u_int pitch, u_int period, u_int volume, int poll)
101 {
102 dev_t audio;
103 int16_t *buf;
104 audio_file_t *file;
105 audio_track_t *ptrack;
106 struct uio auio;
107 struct iovec aiov;
108 u_int i;
109 u_int j;
110 u_int remaincount;
111 u_int remainbytes;
112 u_int wave1count;
113 u_int wave1bytes;
114 u_int bufbytes;
115 u_int len;
116 u_int step;
117 u_int offset;
118 u_int play_sample_rate;
119 u_int mixer_sample_rate;
120
121 KASSERT(volume <= 100);
122
123 /* Playing for 0msec does nothing. */
124 if (period == 0)
125 return;
126
127 /* The audio system isn't built for polling. */
128 if (poll)
129 return;
130
131 buf = NULL;
132 audio = AUDIO_DEVICE | device_unit((device_t)dev);
133
134 /* If not configured, we can't beep. */
135 if (audiobellopen(audio, &file) != 0)
136 return;
137
138 ptrack = file->ptrack;
139 mixer_sample_rate = ptrack->mixer->track_fmt.sample_rate;
140
141 /* Limit pitch */
142 if (pitch < 20)
143 pitch = 20;
144
145 offset = 0;
146 if (pitch <= mixer_sample_rate / 16) {
147 /* 16-point sine wave */
148 step = 1;
149 } else if (pitch <= mixer_sample_rate / 8) {
150 /* 8-point sine wave */
151 step = 2;
152 } else if (pitch <= mixer_sample_rate / 4) {
153 /* 4-point sine wave, aka, triangular wave */
154 step = 4;
155 } else {
156 /* Rectangular wave */
157 if (pitch > mixer_sample_rate / 2)
158 pitch = mixer_sample_rate / 2;
159 step = 8;
160 offset = 4;
161 }
162
163 wave1count = __arraycount(sinewave) / step;
164 play_sample_rate = pitch * wave1count;
165 audiobellsetrate(file, play_sample_rate);
166
167 /* msec to sample count */
168 remaincount = play_sample_rate * period / 1000;
169 /* Roundup to full wave */
170 remaincount = roundup(remaincount, wave1count);
171 remainbytes = remaincount * sizeof(int16_t);
172 wave1bytes = wave1count * sizeof(int16_t);
173
174 /* Based on 3*usrbuf_blksize, but not too small or too large */
175 bufbytes = ptrack->usrbuf_blksize * NBLKHW;
176 if (bufbytes < MINBUFSIZE)
177 bufbytes = MINBUFSIZE;
178 else if (bufbytes > MAXBUFSIZE)
179 bufbytes = MAXBUFSIZE;
180 else
181 bufbytes = roundup(bufbytes, wave1bytes);
182 bufbytes = uimin(bufbytes, remainbytes);
183 KASSERT(bufbytes != 0);
184 buf = malloc(bufbytes, M_TEMP, M_WAITOK);
185 if (buf == NULL)
186 goto out;
187
188 /* Generate sinewave with specified volume */
189 j = offset;
190 for (i = 0; i < bufbytes / sizeof(int16_t); i++) {
191 /* XXX audio already has track volume feature though #if 0 */
192 buf[i] = AUDIO_SCALEDOWN(sinewave[j] * (int)volume, 16);
193 j += step;
194 j %= __arraycount(sinewave);
195 }
196
197 /* Write while paused to avoid inserting silence. */
198 ptrack->is_pause = true;
199 for (; remainbytes > 0; remainbytes -= len) {
200 len = uimin(remainbytes, bufbytes);
201 aiov.iov_base = (void *)buf;
202 aiov.iov_len = len;
203 auio.uio_iov = &aiov;
204 auio.uio_iovcnt = 1;
205 auio.uio_offset = 0;
206 auio.uio_resid = len;
207 auio.uio_rw = UIO_WRITE;
208 UIO_SETUP_SYSSPACE(&auio);
209 if (audiobellwrite(file, &auio) != 0)
210 goto out;
211
212 if (ptrack->usrbuf.used >= ptrack->usrbuf_blksize * NBLKHW)
213 ptrack->is_pause = false;
214 }
215 /* Here we go! */
216 ptrack->is_pause = false;
217 out:
218 if (buf != NULL)
219 free(buf, M_TEMP);
220 audiobellclose(file);
221 }
222