1 #ifndef __SOUND_TIMER_H
2 #define __SOUND_TIMER_H
3 
4 /*
5  *  Timer abstract layer
6  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
7  *		     Abramo Bagnara <abramo@alsa-project.org>
8  *
9  *
10  *   This program is free software; you can redistribute it and/or modify
11  *   it under the terms of the GNU General Public License as published by
12  *   the Free Software Foundation; either version 2 of the License, or
13  *   (at your option) any later version.
14  *
15  *   This program is distributed in the hope that it will be useful,
16  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *   GNU General Public License for more details.
19  *
20  *   You should have received a copy of the GNU General Public License
21  *   along with this program; if not, write to the Free Software
22  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
23  *
24  */
25 
26 #include <sound/asound.h>
27 #include <linux/interrupt.h>
28 
29 #define snd_timer_chip(timer) ((timer)->private_data)
30 
31 #define SNDRV_TIMER_DEVICES	16
32 
33 #define SNDRV_TIMER_DEV_FLG_PCM	0x10000000
34 
35 #define SNDRV_TIMER_HW_AUTO	0x00000001	/* auto trigger is supported */
36 #define SNDRV_TIMER_HW_STOP	0x00000002	/* call stop before start */
37 #define SNDRV_TIMER_HW_SLAVE	0x00000004	/* only slave timer (variable resolution) */
38 #define SNDRV_TIMER_HW_FIRST	0x00000008	/* first tick can be incomplete */
39 #define SNDRV_TIMER_HW_TASKLET	0x00000010	/* timer is called from tasklet */
40 
41 #define SNDRV_TIMER_IFLG_SLAVE	  0x00000001
42 #define SNDRV_TIMER_IFLG_RUNNING  0x00000002
43 #define SNDRV_TIMER_IFLG_START	  0x00000004
44 #define SNDRV_TIMER_IFLG_AUTO	  0x00000008	/* auto restart */
45 #define SNDRV_TIMER_IFLG_FAST	  0x00000010	/* fast callback (do not use tasklet) */
46 #define SNDRV_TIMER_IFLG_CALLBACK 0x00000020	/* timer callback is active */
47 #define SNDRV_TIMER_IFLG_EXCLUSIVE 0x00000040	/* exclusive owner - no more instances */
48 #define SNDRV_TIMER_IFLG_EARLY_EVENT 0x00000080	/* write early event to the poll queue */
49 
50 #define SNDRV_TIMER_FLG_CHANGE	0x00000001
51 #define SNDRV_TIMER_FLG_RESCHED	0x00000002	/* need reschedule */
52 
53 struct snd_timer;
54 
55 struct snd_timer_hardware {
56 	/* -- must be filled with low-level driver */
57 	unsigned int flags;		/* various flags */
58 	unsigned long resolution;	/* average timer resolution for one tick in nsec */
59 	unsigned long resolution_min;	/* minimal resolution */
60 	unsigned long resolution_max;	/* maximal resolution */
61 	unsigned long ticks;		/* max timer ticks per interrupt */
62 	/* -- low-level functions -- */
63 	int (*open) (struct snd_timer * timer);
64 	int (*close) (struct snd_timer * timer);
65 	unsigned long (*c_resolution) (struct snd_timer * timer);
66 	int (*start) (struct snd_timer * timer);
67 	int (*stop) (struct snd_timer * timer);
68 	int (*set_period) (struct snd_timer * timer, unsigned long period_num, unsigned long period_den);
69 	int (*precise_resolution) (struct snd_timer * timer, unsigned long *num, unsigned long *den);
70 };
71 
72 struct snd_timer {
73 	int tmr_class;
74 	struct snd_card *card;
75 	struct module *module;
76 	int tmr_device;
77 	int tmr_subdevice;
78 	char id[64];
79 	char name[80];
80 	unsigned int flags;
81 	int running;			/* running instances */
82 	unsigned long sticks;		/* schedule ticks */
83 	void *private_data;
84 	void (*private_free) (struct snd_timer *timer);
85 	struct snd_timer_hardware hw;
86 	spinlock_t lock;
87 	struct list_head device_list;
88 	struct list_head open_list_head;
89 	struct list_head active_list_head;
90 	struct list_head ack_list_head;
91 	struct list_head sack_list_head; /* slow ack list head */
92 	struct tasklet_struct task_queue;
93 };
94 
95 struct snd_timer_instance {
96 	struct snd_timer *timer;
97 	char *owner;
98 	unsigned int flags;
99 	void *private_data;
100 	void (*private_free) (struct snd_timer_instance *ti);
101 	void (*callback) (struct snd_timer_instance *timeri,
102 			  unsigned long ticks, unsigned long resolution);
103 	void (*ccallback) (struct snd_timer_instance * timeri,
104 			   int event,
105 			   struct timespec * tstamp,
106 			   unsigned long resolution);
107 	void *callback_data;
108 	unsigned long ticks;		/* auto-load ticks when expired */
109 	unsigned long cticks;		/* current ticks */
110 	unsigned long pticks;		/* accumulated ticks for callback */
111 	unsigned long resolution;	/* current resolution for tasklet */
112 	unsigned long lost;		/* lost ticks */
113 	int slave_class;
114 	unsigned int slave_id;
115 	struct list_head open_list;
116 	struct list_head active_list;
117 	struct list_head ack_list;
118 	struct list_head slave_list_head;
119 	struct list_head slave_active_head;
120 	struct snd_timer_instance *master;
121 };
122 
123 /*
124  *  Registering
125  */
126 
127 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid, struct snd_timer **rtimer);
128 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp);
129 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer);
130 int snd_timer_global_free(struct snd_timer *timer);
131 int snd_timer_global_register(struct snd_timer *timer);
132 
133 int snd_timer_open(struct snd_timer_instance **ti, char *owner, struct snd_timer_id *tid, unsigned int slave_id);
134 int snd_timer_close(struct snd_timer_instance *timeri);
135 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri);
136 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks);
137 int snd_timer_stop(struct snd_timer_instance *timeri);
138 int snd_timer_continue(struct snd_timer_instance *timeri);
139 int snd_timer_pause(struct snd_timer_instance *timeri);
140 
141 void snd_timer_interrupt(struct snd_timer *timer, unsigned long ticks_left);
142 
143 #endif /* __SOUND_TIMER_H */
144