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       1                 :            : /* SPDX-License-Identifier: GPL-2.0-or-later */
       2                 :            : /*
       3                 :            :  *  ALSA sequencer Timer
       4                 :            :  *  Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
       5                 :            :  */
       6                 :            : #ifndef __SND_SEQ_TIMER_H
       7                 :            : #define __SND_SEQ_TIMER_H
       8                 :            : 
       9                 :            : #include <sound/timer.h>
      10                 :            : #include <sound/seq_kernel.h>
      11                 :            : 
      12                 :            : struct snd_seq_timer_tick {
      13                 :            :         snd_seq_tick_time_t     cur_tick;       /* current tick */
      14                 :            :         unsigned long           resolution;     /* time per tick in nsec */
      15                 :            :         unsigned long           fraction;       /* current time per tick in nsec */
      16                 :            : };
      17                 :            : 
      18                 :            : struct snd_seq_timer {
      19                 :            :         /* ... tempo / offset / running state */
      20                 :            : 
      21                 :            :         unsigned int            running:1,      /* running state of queue */    
      22                 :            :                                 initialized:1;  /* timer is initialized */
      23                 :            : 
      24                 :            :         unsigned int            tempo;          /* current tempo, us/tick */
      25                 :            :         int                     ppq;            /* time resolution, ticks/quarter */
      26                 :            : 
      27                 :            :         snd_seq_real_time_t     cur_time;       /* current time */
      28                 :            :         struct snd_seq_timer_tick       tick;   /* current tick */
      29                 :            :         int tick_updated;
      30                 :            :         
      31                 :            :         int                     type;           /* timer type */
      32                 :            :         struct snd_timer_id     alsa_id;        /* ALSA's timer ID */
      33                 :            :         struct snd_timer_instance       *timeri;        /* timer instance */
      34                 :            :         unsigned int            ticks;
      35                 :            :         unsigned long           preferred_resolution; /* timer resolution, ticks/sec */
      36                 :            : 
      37                 :            :         unsigned int skew;
      38                 :            :         unsigned int skew_base;
      39                 :            : 
      40                 :            :         struct timespec64       last_update;     /* time of last clock update, used for interpolation */
      41                 :            : 
      42                 :            :         spinlock_t lock;
      43                 :            : };
      44                 :            : 
      45                 :            : 
      46                 :            : /* create new timer (constructor) */
      47                 :            : struct snd_seq_timer *snd_seq_timer_new(void);
      48                 :            : 
      49                 :            : /* delete timer (destructor) */
      50                 :            : void snd_seq_timer_delete(struct snd_seq_timer **tmr);
      51                 :            : 
      52                 :            : /* */
      53                 :          0 : static inline void snd_seq_timer_update_tick(struct snd_seq_timer_tick *tick,
      54                 :            :                                              unsigned long resolution)
      55                 :            : {
      56   [ #  #  #  # ]:          0 :         if (tick->resolution > 0) {
      57                 :          0 :                 tick->fraction += resolution;
      58                 :          0 :                 tick->cur_tick += (unsigned int)(tick->fraction / tick->resolution);
      59                 :          0 :                 tick->fraction %= tick->resolution;
      60                 :            :         }
      61                 :            : }
      62                 :            : 
      63                 :            : 
      64                 :            : /* compare timestamp between events */
      65                 :            : /* return 1 if a >= b; otherwise return 0 */
      66                 :          0 : static inline int snd_seq_compare_tick_time(snd_seq_tick_time_t *a, snd_seq_tick_time_t *b)
      67                 :            : {
      68                 :            :         /* compare ticks */
      69   [ #  #  #  #  :          0 :         return (*a >= *b);
             #  #  #  # ]
      70                 :            : }
      71                 :            : 
      72                 :          0 : static inline int snd_seq_compare_real_time(snd_seq_real_time_t *a, snd_seq_real_time_t *b)
      73                 :            : {
      74                 :            :         /* compare real time */
      75   [ #  #  #  #  :          0 :         if (a->tv_sec > b->tv_sec)
             #  #  #  # ]
      76                 :            :                 return 1;
      77   [ #  #  #  #  :          0 :         if ((a->tv_sec == b->tv_sec) && (a->tv_nsec >= b->tv_nsec))
          #  #  #  #  #  
          #  #  #  #  #  
                   #  # ]
      78                 :            :                 return 1;
      79                 :            :         return 0;
      80                 :            : }
      81                 :            : 
      82                 :            : 
      83                 :          0 : static inline void snd_seq_sanity_real_time(snd_seq_real_time_t *tm)
      84                 :            : {
      85   [ #  #  #  #  :          0 :         while (tm->tv_nsec >= 1000000000) {
                   #  # ]
      86                 :            :                 /* roll-over */
      87                 :          0 :                 tm->tv_nsec -= 1000000000;
      88                 :          0 :                 tm->tv_sec++;
      89                 :            :         }
      90                 :            : }
      91                 :            : 
      92                 :            : 
      93                 :            : /* increment timestamp */
      94                 :          0 : static inline void snd_seq_inc_real_time(snd_seq_real_time_t *tm, snd_seq_real_time_t *inc)
      95                 :            : {
      96                 :          0 :         tm->tv_sec  += inc->tv_sec;
      97                 :          0 :         tm->tv_nsec += inc->tv_nsec;
      98                 :          0 :         snd_seq_sanity_real_time(tm);
      99                 :            : }
     100                 :            : 
     101                 :          0 : static inline void snd_seq_inc_time_nsec(snd_seq_real_time_t *tm, unsigned long nsec)
     102                 :            : {
     103                 :          0 :         tm->tv_nsec  += nsec;
     104                 :          0 :         snd_seq_sanity_real_time(tm);
     105                 :            : }
     106                 :            : 
     107                 :            : /* called by timer isr */
     108                 :            : struct snd_seq_queue;
     109                 :            : int snd_seq_timer_open(struct snd_seq_queue *q);
     110                 :            : int snd_seq_timer_close(struct snd_seq_queue *q);
     111                 :            : int snd_seq_timer_midi_open(struct snd_seq_queue *q);
     112                 :            : int snd_seq_timer_midi_close(struct snd_seq_queue *q);
     113                 :            : void snd_seq_timer_defaults(struct snd_seq_timer *tmr);
     114                 :            : void snd_seq_timer_reset(struct snd_seq_timer *tmr);
     115                 :            : int snd_seq_timer_stop(struct snd_seq_timer *tmr);
     116                 :            : int snd_seq_timer_start(struct snd_seq_timer *tmr);
     117                 :            : int snd_seq_timer_continue(struct snd_seq_timer *tmr);
     118                 :            : int snd_seq_timer_set_tempo(struct snd_seq_timer *tmr, int tempo);
     119                 :            : int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq);
     120                 :            : int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, snd_seq_tick_time_t position);
     121                 :            : int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, snd_seq_real_time_t position);
     122                 :            : int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, unsigned int base);
     123                 :            : snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr,
     124                 :            :                                                bool adjust_ktime);
     125                 :            : snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr);
     126                 :            : 
     127                 :            : extern int seq_default_timer_class;
     128                 :            : extern int seq_default_timer_sclass;
     129                 :            : extern int seq_default_timer_card;
     130                 :            : extern int seq_default_timer_device;
     131                 :            : extern int seq_default_timer_subdevice;
     132                 :            : extern int seq_default_timer_resolution;
     133                 :            : 
     134                 :            : #endif