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