LXR linux/sound/drivers/pcsp/pcsp.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * PC-Speaker driver for Linux
   4 *
   5 * Copyright (C) 1993-1997  Michael Beck
   6 * Copyright (C) 1997-2001  David Woodhouse
   7 * Copyright (C) 2001-2008  Stas Sergeev
   8 */
   9
  10#ifndef __PCSP_H__
  11#define __PCSP_H__
  12
  13#include <linux/hrtimer.h>
  14#include <linux/i8253.h>
  15#include <linux/timex.h>
  16
  17#define PCSP_SOUND_VERSION 0x400        /* read 4.00 */
  18#define PCSP_DEBUG 0
  19
  20/* default timer freq for PC-Speaker: 18643 Hz */
  21#define DIV_18KHZ 64
  22#define MAX_DIV DIV_18KHZ
  23#define CALC_DIV(d) (MAX_DIV >> (d))
  24#define CUR_DIV() CALC_DIV(chip->treble)
  25#define PCSP_MAX_TREBLE 1
  26
  27/* unfortunately, with hrtimers 37KHz does not work very well :( */
  28#define PCSP_DEFAULT_TREBLE 0
  29#define MIN_DIV (MAX_DIV >> PCSP_MAX_TREBLE)
  30
  31/* wild guess */
  32#define PCSP_MIN_LPJ 1000000
  33#define PCSP_DEFAULT_SDIV (DIV_18KHZ >> 1)
  34#define PCSP_DEFAULT_SRATE (PIT_TICK_RATE / PCSP_DEFAULT_SDIV)
  35#define PCSP_INDEX_INC() (1 << (PCSP_MAX_TREBLE - chip->treble))
  36#define PCSP_CALC_RATE(i) (PIT_TICK_RATE / CALC_DIV(i))
  37#define PCSP_RATE() PCSP_CALC_RATE(chip->treble)
  38#define PCSP_MIN_RATE__1 MAX_DIV/PIT_TICK_RATE
  39#define PCSP_MAX_RATE__1 MIN_DIV/PIT_TICK_RATE
  40#define PCSP_MAX_PERIOD_NS (1000000000ULL * PCSP_MIN_RATE__1)
  41#define PCSP_MIN_PERIOD_NS (1000000000ULL * PCSP_MAX_RATE__1)
  42#define PCSP_CALC_NS(div) ({ \
  43        u64 __val = 1000000000ULL * (div); \
  44        do_div(__val, PIT_TICK_RATE); \
  45        __val; \
  46})
  47#define PCSP_PERIOD_NS() PCSP_CALC_NS(CUR_DIV())
  48
  49#define PCSP_MAX_PERIOD_SIZE    (64*1024)
  50#define PCSP_MAX_PERIODS        512
  51#define PCSP_BUFFER_SIZE        (128*1024)
  52
  53struct snd_pcsp {
  54        struct snd_card *card;
  55        struct snd_pcm *pcm;
  56        struct input_dev *input_dev;
  57        struct hrtimer timer;
  58        unsigned short port, irq, dma;
  59        spinlock_t substream_lock;
  60        struct snd_pcm_substream *playback_substream;
  61        unsigned int fmt_size;
  62        unsigned int is_signed;
  63        size_t playback_ptr;
  64        size_t period_ptr;
  65        atomic_t timer_active;
  66        int thalf;
  67        u64 ns_rem;
  68        unsigned char val61;
  69        int enable;
  70        int max_treble;
  71        int treble;
  72        int pcspkr;
  73};
  74
  75extern struct snd_pcsp pcsp_chip;
  76
  77extern enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle);
  78extern void pcsp_sync_stop(struct snd_pcsp *chip);
  79
  80extern int snd_pcsp_new_pcm(struct snd_pcsp *chip);
  81extern int snd_pcsp_new_mixer(struct snd_pcsp *chip, int nopcm);
  82
  83#endif
  84