xref: /linux/sound/drivers/pcsp/pcsp.h (revision 6ee738610f41b59733f63718f0bdbcba7d3a3f12)
1 /*
2  * PC-Speaker driver for Linux
3  *
4  * Copyright (C) 1993-1997  Michael Beck
5  * Copyright (C) 1997-2001  David Woodhouse
6  * Copyright (C) 2001-2008  Stas Sergeev
7  */
8 
9 #ifndef __PCSP_H__
10 #define __PCSP_H__
11 
12 #include <linux/hrtimer.h>
13 #include <linux/timex.h>
14 #if defined(CONFIG_MIPS) || defined(CONFIG_X86)
15 /* Use the global PIT lock ! */
16 #include <asm/i8253.h>
17 #else
18 #include <asm/8253pit.h>
19 static DEFINE_SPINLOCK(i8253_lock);
20 #endif
21 
22 #define PCSP_SOUND_VERSION 0x400	/* read 4.00 */
23 #define PCSP_DEBUG 0
24 
25 /* default timer freq for PC-Speaker: 18643 Hz */
26 #define DIV_18KHZ 64
27 #define MAX_DIV DIV_18KHZ
28 #define CALC_DIV(d) (MAX_DIV >> (d))
29 #define CUR_DIV() CALC_DIV(chip->treble)
30 #define PCSP_MAX_TREBLE 1
31 
32 /* unfortunately, with hrtimers 37KHz does not work very well :( */
33 #define PCSP_DEFAULT_TREBLE 0
34 #define MIN_DIV (MAX_DIV >> PCSP_MAX_TREBLE)
35 
36 /* wild guess */
37 #define PCSP_MIN_LPJ 1000000
38 #define PCSP_DEFAULT_SDIV (DIV_18KHZ >> 1)
39 #define PCSP_DEFAULT_SRATE (PIT_TICK_RATE / PCSP_DEFAULT_SDIV)
40 #define PCSP_INDEX_INC() (1 << (PCSP_MAX_TREBLE - chip->treble))
41 #define PCSP_CALC_RATE(i) (PIT_TICK_RATE / CALC_DIV(i))
42 #define PCSP_RATE() PCSP_CALC_RATE(chip->treble)
43 #define PCSP_MIN_RATE__1 MAX_DIV/PIT_TICK_RATE
44 #define PCSP_MAX_RATE__1 MIN_DIV/PIT_TICK_RATE
45 #define PCSP_MAX_PERIOD_NS (1000000000ULL * PCSP_MIN_RATE__1)
46 #define PCSP_MIN_PERIOD_NS (1000000000ULL * PCSP_MAX_RATE__1)
47 #define PCSP_CALC_NS(div) ({ \
48 	u64 __val = 1000000000ULL * (div); \
49 	do_div(__val, PIT_TICK_RATE); \
50 	__val; \
51 })
52 #define PCSP_PERIOD_NS() PCSP_CALC_NS(CUR_DIV())
53 
54 #define PCSP_MAX_PERIOD_SIZE	(64*1024)
55 #define PCSP_MAX_PERIODS	512
56 #define PCSP_BUFFER_SIZE	(128*1024)
57 
58 struct snd_pcsp {
59 	struct snd_card *card;
60 	struct snd_pcm *pcm;
61 	struct input_dev *input_dev;
62 	struct hrtimer timer;
63 	unsigned short port, irq, dma;
64 	spinlock_t substream_lock;
65 	struct snd_pcm_substream *playback_substream;
66 	unsigned int fmt_size;
67 	unsigned int is_signed;
68 	size_t playback_ptr;
69 	size_t period_ptr;
70 	atomic_t timer_active;
71 	int thalf;
72 	u64 ns_rem;
73 	unsigned char val61;
74 	int enable;
75 	int max_treble;
76 	int treble;
77 	int pcspkr;
78 };
79 
80 extern struct snd_pcsp pcsp_chip;
81 
82 extern enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle);
83 extern void pcsp_sync_stop(struct snd_pcsp *chip);
84 
85 extern int snd_pcsp_new_pcm(struct snd_pcsp *chip);
86 extern int snd_pcsp_new_mixer(struct snd_pcsp *chip);
87 
88 #endif
89