xref: /openbmc/linux/sound/drivers/pcsp/pcsp.h (revision 732a675a)
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 #if defined(CONFIG_MIPS) || defined(CONFIG_X86)
14 /* Use the global PIT lock ! */
15 #include <asm/i8253.h>
16 #else
17 #include <asm/8253pit.h>
18 static DEFINE_SPINLOCK(i8253_lock);
19 #endif
20 
21 #define PCSP_SOUND_VERSION 0x400	/* read 4.00 */
22 #define PCSP_DEBUG 0
23 
24 /* default timer freq for PC-Speaker: 18643 Hz */
25 #define DIV_18KHZ 64
26 #define MAX_DIV DIV_18KHZ
27 #define CALC_DIV(d) (MAX_DIV >> (d))
28 #define CUR_DIV() CALC_DIV(chip->treble)
29 #define PCSP_MAX_TREBLE 1
30 
31 /* unfortunately, with hrtimers 37KHz does not work very well :( */
32 #define PCSP_DEFAULT_TREBLE 0
33 #define MIN_DIV (MAX_DIV >> PCSP_MAX_TREBLE)
34 
35 /* wild guess */
36 #define PCSP_MIN_LPJ 1000000
37 #define PCSP_DEFAULT_SDIV (DIV_18KHZ >> 1)
38 #define PCSP_DEFAULT_SRATE (PIT_TICK_RATE / PCSP_DEFAULT_SDIV)
39 #define PCSP_INDEX_INC() (1 << (PCSP_MAX_TREBLE - chip->treble))
40 #define PCSP_CALC_RATE(i) (PIT_TICK_RATE / CALC_DIV(i))
41 #define PCSP_RATE() PCSP_CALC_RATE(chip->treble)
42 #define PCSP_MIN_RATE__1 MAX_DIV/PIT_TICK_RATE
43 #define PCSP_MAX_RATE__1 MIN_DIV/PIT_TICK_RATE
44 #define PCSP_MAX_PERIOD_NS (1000000000ULL * PCSP_MIN_RATE__1)
45 #define PCSP_MIN_PERIOD_NS (1000000000ULL * PCSP_MAX_RATE__1)
46 #define PCSP_CALC_NS(div) ({ \
47 	u64 __val = 1000000000ULL * (div); \
48 	do_div(__val, PIT_TICK_RATE); \
49 	__val; \
50 })
51 #define PCSP_PERIOD_NS() PCSP_CALC_NS(CUR_DIV())
52 
53 #define PCSP_MAX_PERIOD_SIZE	(64*1024)
54 #define PCSP_MAX_PERIODS	512
55 #define PCSP_BUFFER_SIZE	(128*1024)
56 
57 struct snd_pcsp {
58 	struct snd_card *card;
59 	struct snd_pcm *pcm;
60 	struct input_dev *input_dev;
61 	struct hrtimer timer;
62 	unsigned short port, irq, dma;
63 	spinlock_t substream_lock;
64 	struct snd_pcm_substream *playback_substream;
65 	size_t playback_ptr;
66 	size_t period_ptr;
67 	atomic_t timer_active;
68 	int thalf;
69 	u64 ns_rem;
70 	unsigned char val61;
71 	int enable;
72 	int max_treble;
73 	int treble;
74 	int pcspkr;
75 };
76 
77 extern struct snd_pcsp pcsp_chip;
78 
79 extern enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle);
80 
81 extern int snd_pcsp_new_pcm(struct snd_pcsp *chip);
82 extern int snd_pcsp_new_mixer(struct snd_pcsp *chip);
83 
84 #endif
85