diff options
Diffstat (limited to 'spa/plugins/alsa/test-timer.c')
| -rw-r--r-- | spa/plugins/alsa/test-timer.c | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/spa/plugins/alsa/test-timer.c b/spa/plugins/alsa/test-timer.c new file mode 100644 index 0000000..cc5e5f1 --- /dev/null +++ b/spa/plugins/alsa/test-timer.c @@ -0,0 +1,310 @@ +/* Spa + * + * Copyright © 2020 Wim Taymans + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + */ + +#include <stdio.h> +#include <stdbool.h> +#include <limits.h> +#include <getopt.h> +#include <math.h> +#include <sys/timerfd.h> + +#include <alsa/asoundlib.h> + +#include <spa/utils/dll.h> +#include <spa/utils/defs.h> + +#define DEFAULT_DEVICE "hw:0" + +#define M_PI_M2 (M_PI + M_PI) + +#define BW_PERIOD (SPA_NSEC_PER_SEC * 3) + +struct state { + const char *device; + unsigned int format; + unsigned int rate; + unsigned int channels; + snd_pcm_uframes_t period; + snd_pcm_uframes_t buffer_frames; + + snd_pcm_t *hndl; + int timerfd; + + double max_error; + float accumulator; + + uint64_t next_time; + uint64_t prev_time; + + struct spa_dll dll; +}; + +static int set_timeout(struct state *state, uint64_t time) +{ + struct itimerspec ts; + ts.it_value.tv_sec = time / SPA_NSEC_PER_SEC; + ts.it_value.tv_nsec = time % SPA_NSEC_PER_SEC; + ts.it_interval.tv_sec = 0; + ts.it_interval.tv_nsec = 0; + return timerfd_settime(state->timerfd, TFD_TIMER_ABSTIME, &ts, NULL); +} + +#define CHECK(s,msg,...) { \ + int __err; \ + if ((__err = (s)) < 0) { \ + fprintf(stderr, msg ": %s\n", ##__VA_ARGS__, snd_strerror(__err)); \ + return __err; \ + } \ +} + +#define LOOP(type,areas,scale) { \ + uint32_t i, j; \ + type *samples, v; \ + samples = (type*)((uint8_t*)areas[0].addr + (areas[0].first + offset*areas[0].step) / 8); \ + for (i = 0; i < frames; i++) { \ + state->accumulator += M_PI_M2 * 440 / state->rate; \ + if (state->accumulator >= M_PI_M2) \ + state->accumulator -= M_PI_M2; \ + v = sin(state->accumulator) * scale; \ + for (j = 0; j < state->channels; j++) \ + *samples++ = v; \ + } \ +} + +static int write_period(struct state *state) +{ + snd_pcm_uframes_t frames = state->period; + snd_pcm_uframes_t offset; + const snd_pcm_channel_area_t* areas; + + snd_pcm_mmap_begin(state->hndl, &areas, &offset, &frames); + + switch (state->format) { + case SND_PCM_FORMAT_S32_LE: + LOOP(int32_t, areas, 0x7fffffff); + break; + case SND_PCM_FORMAT_S16_LE: + LOOP(int16_t, areas, 0x7fff); + break; + default: + break; + } + + snd_pcm_mmap_commit(state->hndl, offset, frames) ; + + return 0; +} + +static int on_timer_wakeup(struct state *state) +{ + snd_pcm_sframes_t delay; + double error, corr; +#if 1 + snd_pcm_sframes_t avail; + CHECK(snd_pcm_avail_delay(state->hndl, &avail, &delay), "delay"); +#else + snd_pcm_uframes_t avail; + snd_htimestamp_t tstamp; + uint64_t then; + + CHECK(snd_pcm_htimestamp(state->hndl, &avail, &tstamp), "htimestamp"); + delay = state->buffer_frames - avail; + + then = SPA_TIMESPEC_TO_NSEC(&tstamp); + if (then != 0) { + if (then < state->next_time) { + delay -= (state->next_time - then) * state->rate / SPA_NSEC_PER_SEC; + } else { + delay += (then - state->next_time) * state->rate / SPA_NSEC_PER_SEC; + } + } +#endif + + /* calculate the error, we want to have exactly 1 period of + * samples remaining in the device when we wakeup. */ + error = (double)delay - (double)state->period; + if (error > state->max_error) + error = state->max_error; + else if (error < -state->max_error) + error = -state->max_error; + + /* update the dll with the error, this gives a rate correction */ + corr = spa_dll_update(&state->dll, error); + + /* set our new adjusted timeout. alternatively, this value can + * instead be used to drive a resampler if this device is + * slaved. */ + state->next_time += state->period / corr * 1e9 / state->rate; + set_timeout(state, state->next_time); + + if (state->next_time - state->prev_time > BW_PERIOD) { + state->prev_time = state->next_time; + fprintf(stdout, "corr:%f error:%f bw:%f\n", + corr, error, state->dll.bw); + } + /* pull in new samples write a new period */ + write_period(state); + + return 0; +} + +static unsigned int format_from_string(const char *str) +{ + if (strcmp(str, "S32_LE") == 0) + return SND_PCM_FORMAT_S32_LE; + else if (strcmp(str, "S32_BE") == 0) + return SND_PCM_FORMAT_S32_BE; + else if (strcmp(str, "S24_LE") == 0) + return SND_PCM_FORMAT_S24_LE; + else if (strcmp(str, "S24_BE") == 0) + return SND_PCM_FORMAT_S24_BE; + else if (strcmp(str, "S24_3LE") == 0) + return SND_PCM_FORMAT_S24_3LE; + else if (strcmp(str, "S24_3_BE") == 0) + return SND_PCM_FORMAT_S24_3BE; + else if (strcmp(str, "S16_LE") == 0) + return SND_PCM_FORMAT_S16_LE; + else if (strcmp(str, "S16_BE") == 0) + return SND_PCM_FORMAT_S16_BE; + return 0; +} + +static void show_help(const char *name, bool error) +{ + fprintf(error ? stderr : stdout, "%s [options]\n" + " -h, --help Show this help\n" + " -D, --device device name (default %s)\n", + name, DEFAULT_DEVICE); +} + +int main(int argc, char *argv[]) +{ + struct state state = { 0, }; + snd_pcm_hw_params_t *hparams; + snd_pcm_sw_params_t *sparams; + struct timespec now; + int c; + static const struct option long_options[] = { + { "help", no_argument, NULL, 'h' }, + { "device", required_argument, NULL, 'D' }, + { "format", required_argument, NULL, 'f' }, + { "rate", required_argument, NULL, 'r' }, + { "channels", required_argument, NULL, 'c' }, + { NULL, 0, NULL, 0} + }; + state.device = DEFAULT_DEVICE; + state.format = SND_PCM_FORMAT_S16_LE; + state.rate = 44100; + state.channels = 2; + state.period = 1024; + + while ((c = getopt_long(argc, argv, "hD:f:r:c:", long_options, NULL)) != -1) { + switch (c) { + case 'h': + show_help(argv[0], false); + return 0; + case 'D': + state.device = optarg; + break; + case 'f': + state.format = format_from_string(optarg); + break; + case 'r': + state.rate = atoi(optarg); + break; + case 'c': + state.channels = atoi(optarg); + break; + default: + show_help(argv[0], true); + return -1; + } + } + + CHECK(snd_pcm_open(&state.hndl, state.device, SND_PCM_STREAM_PLAYBACK, 0), + "open %s failed", state.device); + + /* hw params */ + snd_pcm_hw_params_alloca(&hparams); + snd_pcm_hw_params_any(state.hndl, hparams); + CHECK(snd_pcm_hw_params_set_access(state.hndl, hparams, + SND_PCM_ACCESS_MMAP_INTERLEAVED), "set interleaved"); + CHECK(snd_pcm_hw_params_set_format(state.hndl, hparams, + state.format), "set format"); + CHECK(snd_pcm_hw_params_set_channels_near(state.hndl, hparams, + &state.channels), "set channels"); + CHECK(snd_pcm_hw_params_set_rate_near(state.hndl, hparams, + &state.rate, 0), "set rate"); + CHECK(snd_pcm_hw_params(state.hndl, hparams), "hw_params"); + + CHECK(snd_pcm_hw_params_get_buffer_size(hparams, &state.buffer_frames), "get_buffer_size_max"); + + fprintf(stdout, "opened format:%s rate:%u channels:%u\n", + snd_pcm_format_name(state.format), + state.rate, state.channels); + + snd_pcm_sw_params_alloca(&sparams); +#if 0 + CHECK(snd_pcm_sw_params_current(state.hndl, sparams), "sw_params_current"); + CHECK(snd_pcm_sw_params_set_tstamp_mode(state.hndl, sparams, SND_PCM_TSTAMP_ENABLE), + "sw_params_set_tstamp_type"); + CHECK(snd_pcm_sw_params_set_tstamp_type(state.hndl, sparams, SND_PCM_TSTAMP_TYPE_MONOTONIC), + "sw_params_set_tstamp_type"); + CHECK(snd_pcm_sw_params(state.hndl, sparams), "sw_params"); +#endif + + spa_dll_init(&state.dll); + spa_dll_set_bw(&state.dll, SPA_DLL_BW_MAX, state.period, state.rate); + state.max_error = SPA_MAX(256.0, state.period / 2.0f); + + if ((state.timerfd = timerfd_create(CLOCK_MONOTONIC, 0)) < 0) + perror("timerfd"); + + CHECK(snd_pcm_prepare(state.hndl), "prepare"); + + /* before we start, write one period */ + write_period(&state); + + /* set our first timeout for now */ + clock_gettime(CLOCK_MONOTONIC, &now); + state.prev_time = state.next_time = SPA_TIMESPEC_TO_NSEC(&now); + set_timeout(&state, state.next_time); + + /* and start playback */ + CHECK(snd_pcm_start(state.hndl), "start"); + + /* wait for timer to expire and call the wakeup function, + * this can be done in a poll loop as well */ + while (true) { + uint64_t expirations; + CHECK(read(state.timerfd, &expirations, sizeof(expirations)), "read"); + on_timer_wakeup(&state); + } + + snd_pcm_drain(state.hndl); + snd_pcm_close(state.hndl); + close(state.timerfd); + + return EXIT_SUCCESS; +} |