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
  53 struct 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
  75 extern struct snd_pcsp pcsp_chip;
  76
  77 extern enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle);
  78 extern void pcsp_sync_stop(struct snd_pcsp *chip);
  79
  80 extern int snd_pcsp_new_pcm(struct snd_pcsp *chip);
  81 extern int snd_pcsp_new_mixer(struct snd_pcsp *chip, int nopcm);
  82
  83 #endif