1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * OSS compatible sequencer driver
4 *
5 * Timer control routines
6 *
7 * Copyright (C) 1998,99 Takashi Iwai <tiwai@suse.de>
8 */
9
10 #include "seq_oss_timer.h"
11 #include "seq_oss_event.h"
12 #include <sound/seq_oss_legacy.h>
13 #include <linux/slab.h>
14
15 /*
16 */
17 #define MIN_OSS_TEMPO 8
18 #define MAX_OSS_TEMPO 360
19 #define MIN_OSS_TIMEBASE 1
20 #define MAX_OSS_TIMEBASE 1000
21
22 /*
23 */
24 static void calc_alsa_tempo(struct seq_oss_timer *timer);
25 static int send_timer_event(struct seq_oss_devinfo *dp, int type, int value);
26
27
28 /*
29 * create and register a new timer.
30 * if queue is not started yet, start it.
31 */
32 struct seq_oss_timer *
snd_seq_oss_timer_new(struct seq_oss_devinfo * dp)33 snd_seq_oss_timer_new(struct seq_oss_devinfo *dp)
34 {
35 struct seq_oss_timer *rec;
36
37 rec = kzalloc(sizeof(*rec), GFP_KERNEL);
38 if (rec == NULL)
39 return NULL;
40
41 rec->dp = dp;
42 rec->cur_tick = 0;
43 rec->realtime = 0;
44 rec->running = 0;
45 rec->oss_tempo = 60;
46 rec->oss_timebase = 100;
47 calc_alsa_tempo(rec);
48
49 return rec;
50 }
51
52
53 /*
54 * delete timer.
55 * if no more timer exists, stop the queue.
56 */
57 void
snd_seq_oss_timer_delete(struct seq_oss_timer * rec)58 snd_seq_oss_timer_delete(struct seq_oss_timer *rec)
59 {
60 if (rec) {
61 snd_seq_oss_timer_stop(rec);
62 kfree(rec);
63 }
64 }
65
66
67 /*
68 * process one timing event
69 * return 1 : event proceseed -- skip this event
70 * 0 : not a timer event -- enqueue this event
71 */
72 int
snd_seq_oss_process_timer_event(struct seq_oss_timer * rec,union evrec * ev)73 snd_seq_oss_process_timer_event(struct seq_oss_timer *rec, union evrec *ev)
74 {
75 abstime_t parm = ev->t.time;
76
77 if (ev->t.code == EV_TIMING) {
78 switch (ev->t.cmd) {
79 case TMR_WAIT_REL:
80 parm += rec->cur_tick;
81 rec->realtime = 0;
82 fallthrough;
83 case TMR_WAIT_ABS:
84 if (parm == 0) {
85 rec->realtime = 1;
86 } else if (parm >= rec->cur_tick) {
87 rec->realtime = 0;
88 rec->cur_tick = parm;
89 }
90 return 1; /* skip this event */
91
92 case TMR_START:
93 snd_seq_oss_timer_start(rec);
94 return 1;
95
96 }
97 } else if (ev->s.code == SEQ_WAIT) {
98 /* time = from 1 to 3 bytes */
99 parm = (ev->echo >> 8) & 0xffffff;
100 if (parm > rec->cur_tick) {
101 /* set next event time */
102 rec->cur_tick = parm;
103 rec->realtime = 0;
104 }
105 return 1;
106 }
107
108 return 0;
109 }
110
111
112 /*
113 * convert tempo units
114 */
115 static void
calc_alsa_tempo(struct seq_oss_timer * timer)116 calc_alsa_tempo(struct seq_oss_timer *timer)
117 {
118 timer->tempo = (60 * 1000000) / timer->oss_tempo;
119 timer->ppq = timer->oss_timebase;
120 }
121
122
123 /*
124 * dispatch a timer event
125 */
126 static int
send_timer_event(struct seq_oss_devinfo * dp,int type,int value)127 send_timer_event(struct seq_oss_devinfo *dp, int type, int value)
128 {
129 struct snd_seq_event ev;
130
131 memset(&ev, 0, sizeof(ev));
132 ev.type = type;
133 ev.source.client = dp->cseq;
134 ev.source.port = 0;
135 ev.dest.client = SNDRV_SEQ_CLIENT_SYSTEM;
136 ev.dest.port = SNDRV_SEQ_PORT_SYSTEM_TIMER;
137 ev.queue = dp->queue;
138 ev.data.queue.queue = dp->queue;
139 ev.data.queue.param.value = value;
140 return snd_seq_kernel_client_dispatch(dp->cseq, &ev, 1, 0);
141 }
142
143 /*
144 * set queue tempo and start queue
145 */
146 int
snd_seq_oss_timer_start(struct seq_oss_timer * timer)147 snd_seq_oss_timer_start(struct seq_oss_timer *timer)
148 {
149 struct seq_oss_devinfo *dp = timer->dp;
150 struct snd_seq_queue_tempo tmprec;
151
152 if (timer->running)
153 snd_seq_oss_timer_stop(timer);
154
155 memset(&tmprec, 0, sizeof(tmprec));
156 tmprec.queue = dp->queue;
157 tmprec.ppq = timer->ppq;
158 tmprec.tempo = timer->tempo;
159 snd_seq_set_queue_tempo(dp->cseq, &tmprec);
160
161 send_timer_event(dp, SNDRV_SEQ_EVENT_START, 0);
162 timer->running = 1;
163 timer->cur_tick = 0;
164 return 0;
165 }
166
167
168 /*
169 * stop queue
170 */
171 int
snd_seq_oss_timer_stop(struct seq_oss_timer * timer)172 snd_seq_oss_timer_stop(struct seq_oss_timer *timer)
173 {
174 if (! timer->running)
175 return 0;
176 send_timer_event(timer->dp, SNDRV_SEQ_EVENT_STOP, 0);
177 timer->running = 0;
178 return 0;
179 }
180
181
182 /*
183 * continue queue
184 */
185 int
snd_seq_oss_timer_continue(struct seq_oss_timer * timer)186 snd_seq_oss_timer_continue(struct seq_oss_timer *timer)
187 {
188 if (timer->running)
189 return 0;
190 send_timer_event(timer->dp, SNDRV_SEQ_EVENT_CONTINUE, 0);
191 timer->running = 1;
192 return 0;
193 }
194
195
196 /*
197 * change queue tempo
198 */
199 int
snd_seq_oss_timer_tempo(struct seq_oss_timer * timer,int value)200 snd_seq_oss_timer_tempo(struct seq_oss_timer *timer, int value)
201 {
202 if (value < MIN_OSS_TEMPO)
203 value = MIN_OSS_TEMPO;
204 else if (value > MAX_OSS_TEMPO)
205 value = MAX_OSS_TEMPO;
206 timer->oss_tempo = value;
207 calc_alsa_tempo(timer);
208 if (timer->running)
209 send_timer_event(timer->dp, SNDRV_SEQ_EVENT_TEMPO, timer->tempo);
210 return 0;
211 }
212
213
214 /*
215 * ioctls
216 */
217 int
snd_seq_oss_timer_ioctl(struct seq_oss_timer * timer,unsigned int cmd,int __user * arg)218 snd_seq_oss_timer_ioctl(struct seq_oss_timer *timer, unsigned int cmd, int __user *arg)
219 {
220 int value;
221
222 if (cmd == SNDCTL_SEQ_CTRLRATE) {
223 /* if *arg == 0, just return the current rate */
224 if (get_user(value, arg))
225 return -EFAULT;
226 if (value)
227 return -EINVAL;
228 value = ((timer->oss_tempo * timer->oss_timebase) + 30) / 60;
229 return put_user(value, arg) ? -EFAULT : 0;
230 }
231
232 if (timer->dp->seq_mode == SNDRV_SEQ_OSS_MODE_SYNTH)
233 return 0;
234
235 switch (cmd) {
236 case SNDCTL_TMR_START:
237 return snd_seq_oss_timer_start(timer);
238 case SNDCTL_TMR_STOP:
239 return snd_seq_oss_timer_stop(timer);
240 case SNDCTL_TMR_CONTINUE:
241 return snd_seq_oss_timer_continue(timer);
242 case SNDCTL_TMR_TEMPO:
243 if (get_user(value, arg))
244 return -EFAULT;
245 return snd_seq_oss_timer_tempo(timer, value);
246 case SNDCTL_TMR_TIMEBASE:
247 if (get_user(value, arg))
248 return -EFAULT;
249 if (value < MIN_OSS_TIMEBASE)
250 value = MIN_OSS_TIMEBASE;
251 else if (value > MAX_OSS_TIMEBASE)
252 value = MAX_OSS_TIMEBASE;
253 timer->oss_timebase = value;
254 calc_alsa_tempo(timer);
255 return 0;
256
257 case SNDCTL_TMR_METRONOME:
258 case SNDCTL_TMR_SELECT:
259 case SNDCTL_TMR_SOURCE:
260 /* not supported */
261 return 0;
262 }
263 return 0;
264 }
265