sound/drivers/pcsp/pcsp.h

   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 extern void pcsp_sync_stop(struct snd_pcsp *chip);
  81
  82 extern int snd_pcsp_new_pcm(struct snd_pcsp *chip);
  83 extern int snd_pcsp_new_mixer(struct snd_pcsp *chip);
  84
  85 #endif