/******************************************************************************* * Copyright (C) 2018 Cadence Design Systems, Inc. * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to use this Software with Cadence processor cores only and * not with any other processors and platforms, subject to * the following conditions: * * The above copyright notice and this permission notice 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 #include #include #include #include #include #include #include #include #include #include #include #include #define __force //#define __bitwise #define __user #include #include #define PARAM_MAX SNDRV_PCM_HW_PARAM_LAST_INTERVAL /* Logs information into a string; follows snprintf() in that * offset may be greater than size, and though no characters are copied * into string, characters are still counted into offset. */ #define STRLOG(string, offset, size, ...) \ do { int temp, clipoffset = offset > size ? size : offset; \ temp = snprintf(string + clipoffset, size - clipoffset, __VA_ARGS__); \ if (temp > 0) offset += temp; } while (0) #ifndef ARRAY_SIZE #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0])) #endif /* refer to SNDRV_PCM_ACCESS_##index in sound/asound.h. */ static const char * const access_lookup[] = { "MMAP_INTERLEAVED", "MMAP_NONINTERLEAVED", "MMAP_COMPLEX", "RW_INTERLEAVED", "RW_NONINTERLEAVED", }; /* refer to SNDRV_PCM_FORMAT_##index in sound/asound.h. */ static const char * const format_lookup[] = { /*[0] =*/ "S8", "U8", "S16_LE", "S16_BE", "U16_LE", "U16_BE", "S24_LE", "S24_BE", "U24_LE", "U24_BE", "S32_LE", "S32_BE", "U32_LE", "U32_BE", "FLOAT_LE", "FLOAT_BE", "FLOAT64_LE", "FLOAT64_BE", "IEC958_SUBFRAME_LE", "IEC958_SUBFRAME_BE", "MU_LAW", "A_LAW", "IMA_ADPCM", "MPEG", /*[24] =*/ "GSM", /* gap */ [31] = "SPECIAL", "S24_3LE", "S24_3BE", "U24_3LE", "U24_3BE", "S20_3LE", "S20_3BE", "U20_3LE", "U20_3BE", "S18_3LE", "S18_3BE", "U18_3LE", /*[43] =*/ "U18_3BE", #if 0 /* recent additions, may not be present on local asound.h */ "G723_24", "G723_24_1B", "G723_40", "G723_40_1B", "DSD_U8", "DSD_U16_LE", #endif }; /* refer to SNDRV_PCM_SUBFORMAT_##index in sound/asound.h. */ static const char * const subformat_lookup[] = { "STD", }; static inline int param_is_mask(int p) { return (p >= SNDRV_PCM_HW_PARAM_FIRST_MASK) && (p <= SNDRV_PCM_HW_PARAM_LAST_MASK); } static inline int param_is_interval(int p) { return (p >= SNDRV_PCM_HW_PARAM_FIRST_INTERVAL) && (p <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL); } static inline struct snd_interval *param_to_interval(struct snd_pcm_hw_params *p, int n) { return &(p->intervals[n - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]); } static inline struct snd_mask *param_to_mask(struct snd_pcm_hw_params *p, int n) { return &(p->masks[n - SNDRV_PCM_HW_PARAM_FIRST_MASK]); } static void param_set_mask(struct snd_pcm_hw_params *p, int n, unsigned int bit) { if (bit >= SNDRV_MASK_MAX) return; if (param_is_mask(n)) { struct snd_mask *m = param_to_mask(p, n); m->bits[0] = 0; m->bits[1] = 0; m->bits[bit >> 5] |= (1 << (bit & 31)); } } static void param_set_min(struct snd_pcm_hw_params *p, int n, unsigned int val) { if (param_is_interval(n)) { struct snd_interval *i = param_to_interval(p, n); i->min = val; } } static unsigned int param_get_min(struct snd_pcm_hw_params *p, int n) { if (param_is_interval(n)) { struct snd_interval *i = param_to_interval(p, n); return i->min; } return 0; } static void param_set_max(struct snd_pcm_hw_params *p, int n, unsigned int val) { if (param_is_interval(n)) { struct snd_interval *i = param_to_interval(p, n); i->max = val; } } static unsigned int param_get_max(struct snd_pcm_hw_params *p, int n) { if (param_is_interval(n)) { struct snd_interval *i = param_to_interval(p, n); return i->max; } return 0; } static void param_set_int(struct snd_pcm_hw_params *p, int n, unsigned int val) { if (param_is_interval(n)) { struct snd_interval *i = param_to_interval(p, n); i->min = val; i->max = val; i->integer = 1; } } static unsigned int param_get_int(struct snd_pcm_hw_params *p, int n) { if (param_is_interval(n)) { struct snd_interval *i = param_to_interval(p, n); if (i->integer) return i->max; } return 0; } static void param_init(struct snd_pcm_hw_params *p) { int n; memset(p, 0, sizeof(*p)); for (n = SNDRV_PCM_HW_PARAM_FIRST_MASK; n <= SNDRV_PCM_HW_PARAM_LAST_MASK; n++) { struct snd_mask *m = param_to_mask(p, n); m->bits[0] = ~0; m->bits[1] = ~0; } for (n = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; n <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; n++) { struct snd_interval *i = param_to_interval(p, n); i->min = 0; i->max = ~0; } p->rmask = ~0U; p->cmask = 0; p->info = ~0U; } #define PCM_ERROR_MAX 128 struct pcm { int fd; unsigned int flags; int running:1; int prepared:1; int underruns; unsigned int buffer_size; unsigned int boundary; char error[PCM_ERROR_MAX]; struct pcm_config config; struct snd_pcm_mmap_status *mmap_status; struct snd_pcm_mmap_control *mmap_control; struct snd_pcm_sync_ptr *sync_ptr; void *mmap_buffer; unsigned int noirq_frames_per_msec; int wait_for_avail_min; unsigned int subdevice; }; unsigned int pcm_get_buffer_size(struct pcm *pcm) { return pcm->buffer_size; } const char* pcm_get_error(struct pcm *pcm) { return pcm->error; } unsigned int pcm_get_subdevice(struct pcm *pcm) { return pcm->subdevice; } static int oops(struct pcm *pcm, int e, const char *fmt, ...) { va_list ap; int sz; va_start(ap, fmt); vsnprintf(pcm->error, PCM_ERROR_MAX, fmt, ap); va_end(ap); sz = strlen(pcm->error); if (errno) snprintf(pcm->error + sz, PCM_ERROR_MAX - sz, ": %s", strerror(e)); return -1; } static unsigned int pcm_format_to_alsa(enum pcm_format format) { switch (format) { case PCM_FORMAT_S32_LE: return SNDRV_PCM_FORMAT_S32_LE; case PCM_FORMAT_S8: return SNDRV_PCM_FORMAT_S8; case PCM_FORMAT_S24_3LE: return SNDRV_PCM_FORMAT_S24_3LE; case PCM_FORMAT_S24_LE: return SNDRV_PCM_FORMAT_S24_LE; default: case PCM_FORMAT_S16_LE: return SNDRV_PCM_FORMAT_S16_LE; }; } unsigned int pcm_format_to_bits(enum pcm_format format) { switch (format) { case PCM_FORMAT_S32_LE: case PCM_FORMAT_S24_LE: return 32; case PCM_FORMAT_S24_3LE: return 24; default: case PCM_FORMAT_S16_LE: return 16; }; } unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes) { return bytes / (pcm->config.channels * (pcm_format_to_bits(pcm->config.format) >> 3)); } unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames) { return frames * pcm->config.channels * (pcm_format_to_bits(pcm->config.format) >> 3); } static int pcm_sync_ptr(struct pcm *pcm, int flags) { if (pcm->sync_ptr) { pcm->sync_ptr->flags = flags; if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SYNC_PTR, pcm->sync_ptr) < 0) return -1; } return 0; } static int pcm_hw_mmap_status(struct pcm *pcm) { if (pcm->sync_ptr) return 0; int page_size = sysconf(_SC_PAGE_SIZE); pcm->mmap_status = mmap(NULL, page_size, PROT_READ, MAP_FILE | MAP_SHARED, pcm->fd, SNDRV_PCM_MMAP_OFFSET_STATUS); if (pcm->mmap_status == MAP_FAILED) pcm->mmap_status = NULL; if (!pcm->mmap_status) goto mmap_error; pcm->mmap_control = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, pcm->fd, SNDRV_PCM_MMAP_OFFSET_CONTROL); if (pcm->mmap_control == MAP_FAILED) pcm->mmap_control = NULL; if (!pcm->mmap_control) { munmap(pcm->mmap_status, page_size); pcm->mmap_status = NULL; goto mmap_error; } if (pcm->flags & PCM_MMAP) pcm->mmap_control->avail_min = pcm->config.avail_min; else pcm->mmap_control->avail_min = 1; return 0; mmap_error: pcm->sync_ptr = calloc(1, sizeof(*pcm->sync_ptr)); if (!pcm->sync_ptr) return -ENOMEM; pcm->mmap_status = &pcm->sync_ptr->s.status; pcm->mmap_control = &pcm->sync_ptr->c.control; if (pcm->flags & PCM_MMAP) pcm->mmap_control->avail_min = pcm->config.avail_min; else pcm->mmap_control->avail_min = 1; pcm_sync_ptr(pcm, 0); return 0; } static void pcm_hw_munmap_status(struct pcm *pcm) { if (pcm->sync_ptr) { free(pcm->sync_ptr); pcm->sync_ptr = NULL; } else { int page_size = sysconf(_SC_PAGE_SIZE); if (pcm->mmap_status) munmap(pcm->mmap_status, page_size); if (pcm->mmap_control) munmap(pcm->mmap_control, page_size); } pcm->mmap_status = NULL; pcm->mmap_control = NULL; } static int pcm_areas_copy(struct pcm *pcm, unsigned int pcm_offset, char *buf, unsigned int src_offset, unsigned int frames) { int size_bytes = pcm_frames_to_bytes(pcm, frames); int pcm_offset_bytes = pcm_frames_to_bytes(pcm, pcm_offset); int src_offset_bytes = pcm_frames_to_bytes(pcm, src_offset); /* interleaved only atm */ if (pcm->flags & PCM_IN) memcpy(buf + src_offset_bytes, (char*)pcm->mmap_buffer + pcm_offset_bytes, size_bytes); else memcpy((char*)pcm->mmap_buffer + pcm_offset_bytes, buf + src_offset_bytes, size_bytes); return 0; } static int pcm_mmap_transfer_areas(struct pcm *pcm, char *buf, unsigned int offset, unsigned int size) { void *pcm_areas; int commit; unsigned int pcm_offset, frames, count = 0; while (size > 0) { frames = size; pcm_mmap_begin(pcm, &pcm_areas, &pcm_offset, &frames); pcm_areas_copy(pcm, pcm_offset, buf, offset, frames); commit = pcm_mmap_commit(pcm, pcm_offset, frames); if (commit < 0) { oops(pcm, commit, "failed to commit %d frames\n", frames); return commit; } offset += commit; count += commit; size -= commit; } return count; } int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, struct timespec *tstamp) { int frames; int rc; snd_pcm_uframes_t hw_ptr; if (!pcm_is_ready(pcm)) return -1; rc = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL|SNDRV_PCM_SYNC_PTR_HWSYNC); if (rc < 0) return -1; if ((pcm->mmap_status->state != PCM_STATE_RUNNING) && (pcm->mmap_status->state != PCM_STATE_DRAINING)) return -1; *tstamp = pcm->mmap_status->tstamp; if (tstamp->tv_sec == 0 && tstamp->tv_nsec == 0) return -1; hw_ptr = pcm->mmap_status->hw_ptr; if (pcm->flags & PCM_IN) frames = hw_ptr - pcm->mmap_control->appl_ptr; else frames = hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr; if (frames < 0) frames += pcm->boundary; else if (frames > (int)pcm->boundary) frames -= pcm->boundary; *avail = (unsigned int)frames; return 0; } int pcm_write(struct pcm *pcm, const void *data, unsigned int count) { struct snd_xferi x; if (pcm->flags & PCM_IN) return -EINVAL; x.buf = (void*)data; x.frames = count / (pcm->config.channels * pcm_format_to_bits(pcm->config.format) / 8); for (;;) { if (!pcm->running) { int prepare_error = pcm_prepare(pcm); if (prepare_error) return prepare_error; if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x)) return oops(pcm, errno, "cannot write initial data"); pcm->running = 1; return 0; } if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x)) { pcm->prepared = 0; pcm->running = 0; if (errno == EPIPE) { /* we failed to make our window -- try to restart if we are * allowed to do so. Otherwise, simply allow the EPIPE error to * propagate up to the app level */ pcm->underruns++; if (pcm->flags & PCM_NORESTART) return -EPIPE; continue; } return oops(pcm, errno, "cannot write stream data"); } return 0; } } int pcm_read(struct pcm *pcm, void *data, unsigned int count) { struct snd_xferi x; if (!(pcm->flags & PCM_IN)) return -EINVAL; x.buf = data; x.frames = count / (pcm->config.channels * pcm_format_to_bits(pcm->config.format) / 8); for (;;) { if (!pcm->running) { if (pcm_start(pcm) < 0) { fprintf(stderr, "start error"); return -errno; } } if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_READI_FRAMES, &x)) { pcm->prepared = 0; pcm->running = 0; if (errno == EPIPE) { /* we failed to make our window -- try to restart */ pcm->underruns++; continue; } return oops(pcm, errno, "cannot read stream data"); } return 0; } } static struct pcm bad_pcm = { .fd = -1, }; struct pcm_params *pcm_params_get(unsigned int card, unsigned int device, unsigned int flags) { struct snd_pcm_hw_params *params; char fn[256]; int fd; snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device, flags & PCM_IN ? 'c' : 'p'); fd = open(fn, O_RDWR); if (fd < 0) { fprintf(stderr, "cannot open device '%s'\n", fn); goto err_open; } params = calloc(1, sizeof(struct snd_pcm_hw_params)); if (!params) goto err_calloc; param_init(params); if (ioctl(fd, SNDRV_PCM_IOCTL_HW_REFINE, params)) { fprintf(stderr, "SNDRV_PCM_IOCTL_HW_REFINE error (%d)\n", errno); goto err_hw_refine; } close(fd); return (struct pcm_params *)params; err_hw_refine: free(params); err_calloc: close(fd); err_open: return NULL; } void pcm_params_free(struct pcm_params *pcm_params) { struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; if (params) free(params); } static int pcm_param_to_alsa(enum pcm_param param) { switch (param) { case PCM_PARAM_ACCESS: return SNDRV_PCM_HW_PARAM_ACCESS; case PCM_PARAM_FORMAT: return SNDRV_PCM_HW_PARAM_FORMAT; case PCM_PARAM_SUBFORMAT: return SNDRV_PCM_HW_PARAM_SUBFORMAT; case PCM_PARAM_SAMPLE_BITS: return SNDRV_PCM_HW_PARAM_SAMPLE_BITS; break; case PCM_PARAM_FRAME_BITS: return SNDRV_PCM_HW_PARAM_FRAME_BITS; break; case PCM_PARAM_CHANNELS: return SNDRV_PCM_HW_PARAM_CHANNELS; break; case PCM_PARAM_RATE: return SNDRV_PCM_HW_PARAM_RATE; break; case PCM_PARAM_PERIOD_TIME: return SNDRV_PCM_HW_PARAM_PERIOD_TIME; break; case PCM_PARAM_PERIOD_SIZE: return SNDRV_PCM_HW_PARAM_PERIOD_SIZE; break; case PCM_PARAM_PERIOD_BYTES: return SNDRV_PCM_HW_PARAM_PERIOD_BYTES; break; case PCM_PARAM_PERIODS: return SNDRV_PCM_HW_PARAM_PERIODS; break; case PCM_PARAM_BUFFER_TIME: return SNDRV_PCM_HW_PARAM_BUFFER_TIME; break; case PCM_PARAM_BUFFER_SIZE: return SNDRV_PCM_HW_PARAM_BUFFER_SIZE; break; case PCM_PARAM_BUFFER_BYTES: return SNDRV_PCM_HW_PARAM_BUFFER_BYTES; break; case PCM_PARAM_TICK_TIME: return SNDRV_PCM_HW_PARAM_TICK_TIME; break; default: return -1; } } struct pcm_mask *pcm_params_get_mask(struct pcm_params *pcm_params, enum pcm_param param) { int p; struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; if (params == NULL) { return NULL; } p = pcm_param_to_alsa(param); if (p < 0 || !param_is_mask(p)) { return NULL; } return (struct pcm_mask *)param_to_mask(params, p); } unsigned int pcm_params_get_min(struct pcm_params *pcm_params, enum pcm_param param) { struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; int p; if (!params) return 0; p = pcm_param_to_alsa(param); if (p < 0) return 0; return param_get_min(params, p); } void pcm_params_set_min(struct pcm_params *pcm_params, enum pcm_param param, unsigned int val) { struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; int p; if (!params) return; p = pcm_param_to_alsa(param); if (p < 0) return; param_set_min(params, p, val); } unsigned int pcm_params_get_max(struct pcm_params *pcm_params, enum pcm_param param) { struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; int p; if (!params) return 0; p = pcm_param_to_alsa(param); if (p < 0) return 0; return param_get_max(params, p); } void pcm_params_set_max(struct pcm_params *pcm_params, enum pcm_param param, unsigned int val) { struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; int p; if (!params) return; p = pcm_param_to_alsa(param); if (p < 0) return; param_set_max(params, p, val); } static int pcm_mask_test(struct pcm_mask *m, unsigned int index) { const unsigned int bitshift = 5; /* for 32 bit integer */ const unsigned int bitmask = (1 << bitshift) - 1; unsigned int element; element = index >> bitshift; if (element >= ARRAY_SIZE(m->bits)) return 0; /* for safety, but should never occur */ return (m->bits[element] >> (index & bitmask)) & 1; } static int pcm_mask_to_string(struct pcm_mask *m, char *string, unsigned int size, char *mask_name, const char * const *bit_array_name, size_t bit_array_size) { unsigned int i; unsigned int offset = 0; if (m == NULL) return 0; if (bit_array_size < 32) { STRLOG(string, offset, size, "%12s:\t%#08x\n", mask_name, m->bits[0]); } else { /* spans two or more bitfields, print with an array index */ for (i = 0; i < (bit_array_size + 31) >> 5; ++i) { STRLOG(string, offset, size, "%9s[%d]:\t%#08x\n", mask_name, i, m->bits[i]); } } for (i = 0; i < bit_array_size; ++i) { if (pcm_mask_test(m, i)) { STRLOG(string, offset, size, "%12s \t%s\n", "", bit_array_name[i]); } } return offset; } int pcm_params_to_string(struct pcm_params *params, char *string, unsigned int size) { struct pcm_mask *m; unsigned int min, max; unsigned int clipoffset, offset; m = pcm_params_get_mask(params, PCM_PARAM_ACCESS); offset = pcm_mask_to_string(m, string, size, "Access", access_lookup, ARRAY_SIZE(access_lookup)); m = pcm_params_get_mask(params, PCM_PARAM_FORMAT); clipoffset = offset > size ? size : offset; offset += pcm_mask_to_string(m, string + clipoffset, size - clipoffset, "Format", format_lookup, ARRAY_SIZE(format_lookup)); m = pcm_params_get_mask(params, PCM_PARAM_SUBFORMAT); clipoffset = offset > size ? size : offset; offset += pcm_mask_to_string(m, string + clipoffset, size - clipoffset, "Subformat", subformat_lookup, ARRAY_SIZE(subformat_lookup)); min = pcm_params_get_min(params, PCM_PARAM_RATE); max = pcm_params_get_max(params, PCM_PARAM_RATE); STRLOG(string, offset, size, " Rate:\tmin=%uHz\tmax=%uHz\n", min, max); min = pcm_params_get_min(params, PCM_PARAM_CHANNELS); max = pcm_params_get_max(params, PCM_PARAM_CHANNELS); STRLOG(string, offset, size, " Channels:\tmin=%u\t\tmax=%u\n", min, max); min = pcm_params_get_min(params, PCM_PARAM_SAMPLE_BITS); max = pcm_params_get_max(params, PCM_PARAM_SAMPLE_BITS); STRLOG(string, offset, size, " Sample bits:\tmin=%u\t\tmax=%u\n", min, max); min = pcm_params_get_min(params, PCM_PARAM_PERIOD_SIZE); max = pcm_params_get_max(params, PCM_PARAM_PERIOD_SIZE); STRLOG(string, offset, size, " Period size:\tmin=%u\t\tmax=%u\n", min, max); min = pcm_params_get_min(params, PCM_PARAM_PERIODS); max = pcm_params_get_max(params, PCM_PARAM_PERIODS); STRLOG(string, offset, size, "Period count:\tmin=%u\t\tmax=%u\n", min, max); return offset; } int pcm_params_format_test(struct pcm_params *params, enum pcm_format format) { unsigned int alsa_format = pcm_format_to_alsa(format); if (alsa_format == SNDRV_PCM_FORMAT_S16_LE && format != PCM_FORMAT_S16_LE) return 0; /* caution: format not recognized is equivalent to S16_LE */ return pcm_mask_test(pcm_params_get_mask(params, PCM_PARAM_FORMAT), alsa_format); } int pcm_close(struct pcm *pcm) { if (pcm == &bad_pcm) return 0; pcm_hw_munmap_status(pcm); if (pcm->flags & PCM_MMAP) { pcm_stop(pcm); munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); } if (pcm->fd >= 0) close(pcm->fd); pcm->prepared = 0; pcm->running = 0; pcm->buffer_size = 0; pcm->fd = -1; free(pcm); return 0; } struct pcm *pcm_open(unsigned int card, unsigned int device, unsigned int flags, struct pcm_config *config) { struct pcm *pcm; struct snd_pcm_info info; struct snd_pcm_hw_params params; struct snd_pcm_sw_params sparams; char fn[256]; int rc; pcm = calloc(1, sizeof(struct pcm)); if (!pcm || !config) return &bad_pcm; /* TODO: could support default config here */ pcm->config = *config; snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device, flags & PCM_IN ? 'c' : 'p'); pcm->flags = flags; pcm->fd = open(fn, O_RDWR|O_NONBLOCK); if (pcm->fd < 0) { oops(pcm, errno, "cannot open device '%s'", fn); return pcm; } if (fcntl(pcm->fd, F_SETFL, fcntl(pcm->fd, F_GETFL) & ~O_NONBLOCK) < 0) { oops(pcm, errno, "failed to reset blocking mode '%s'", fn); goto fail_close; } if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_INFO, &info)) { oops(pcm, errno, "cannot get info"); goto fail_close; } pcm->subdevice = info.subdevice; param_init(¶ms); param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_FORMAT, pcm_format_to_alsa(config->format)); param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_SUBFORMAT, SNDRV_PCM_SUBFORMAT_STD); param_set_min(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, config->period_size); param_set_int(¶ms, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, pcm_format_to_bits(config->format)); param_set_int(¶ms, SNDRV_PCM_HW_PARAM_FRAME_BITS, pcm_format_to_bits(config->format) * config->channels); param_set_int(¶ms, SNDRV_PCM_HW_PARAM_CHANNELS, config->channels); param_set_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS, config->period_count); param_set_int(¶ms, SNDRV_PCM_HW_PARAM_RATE, config->rate); if (flags & PCM_NOIRQ) { if (!(flags & PCM_MMAP)) { oops(pcm, -EINVAL, "noirq only currently supported with mmap()."); goto fail_close; } params.flags |= SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP; pcm->noirq_frames_per_msec = config->rate / 1000; } if (flags & PCM_MMAP) param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS, SNDRV_PCM_ACCESS_MMAP_INTERLEAVED); else param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS, SNDRV_PCM_ACCESS_RW_INTERLEAVED); if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_HW_PARAMS, ¶ms)) { oops(pcm, errno, "cannot set hw params"); goto fail_close; } /* get our refined hw_params */ config->period_size = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE); config->period_count = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS); pcm->buffer_size = config->period_count * config->period_size; if (flags & PCM_MMAP) { pcm->mmap_buffer = mmap(NULL, pcm_frames_to_bytes(pcm, pcm->buffer_size), PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, pcm->fd, 0); if (pcm->mmap_buffer == MAP_FAILED) { oops(pcm, -errno, "failed to mmap buffer %d bytes\n", pcm_frames_to_bytes(pcm, pcm->buffer_size)); goto fail_close; } } memset(&sparams, 0, sizeof(sparams)); sparams.tstamp_mode = SNDRV_PCM_TSTAMP_ENABLE; sparams.period_step = 1; if (!config->start_threshold) { if (pcm->flags & PCM_IN) pcm->config.start_threshold = sparams.start_threshold = 1; else pcm->config.start_threshold = sparams.start_threshold = config->period_count * config->period_size / 2; } else sparams.start_threshold = config->start_threshold; /* pick a high stop threshold - todo: does this need further tuning */ if (!config->stop_threshold) { if (pcm->flags & PCM_IN) pcm->config.stop_threshold = sparams.stop_threshold = config->period_count * config->period_size * 10; else pcm->config.stop_threshold = sparams.stop_threshold = config->period_count * config->period_size; } else sparams.stop_threshold = config->stop_threshold; if (!pcm->config.avail_min) { if (pcm->flags & PCM_MMAP) pcm->config.avail_min = sparams.avail_min = pcm->config.period_size; else pcm->config.avail_min = sparams.avail_min = 1; } else sparams.avail_min = config->avail_min; sparams.xfer_align = config->period_size / 2; /* needed for old kernels */ sparams.silence_threshold = config->silence_threshold; sparams.silence_size = config->silence_size; pcm->boundary = sparams.boundary = pcm->buffer_size; while (pcm->boundary * 2 <= INT_MAX - pcm->buffer_size) pcm->boundary *= 2; if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) { oops(pcm, errno, "cannot set sw params"); goto fail; } rc = pcm_hw_mmap_status(pcm); if (rc < 0) { oops(pcm, rc, "mmap status failed"); goto fail; } #ifdef SNDRV_PCM_IOCTL_TTSTAMP if (pcm->flags & PCM_MONOTONIC) { int arg = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC; rc = ioctl(pcm->fd, SNDRV_PCM_IOCTL_TTSTAMP, &arg); if (rc < 0) { oops(pcm, rc, "cannot set timestamp type"); goto fail; } } #endif pcm->underruns = 0; return pcm; fail: if (flags & PCM_MMAP) munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); fail_close: close(pcm->fd); pcm->fd = -1; return pcm; } int pcm_is_ready(struct pcm *pcm) { return pcm->fd >= 0; } int pcm_prepare(struct pcm *pcm) { if (pcm->prepared) return 0; if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_PREPARE) < 0) return oops(pcm, errno, "cannot prepare channel"); pcm->prepared = 1; return 0; } int pcm_start(struct pcm *pcm) { int prepare_error = pcm_prepare(pcm); if (prepare_error) return prepare_error; if (pcm->flags & PCM_MMAP) pcm_sync_ptr(pcm, 0); if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_START) < 0) return oops(pcm, errno, "cannot start channel"); pcm->running = 1; return 0; } int pcm_stop(struct pcm *pcm) { if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DROP) < 0) return oops(pcm, errno, "cannot stop channel"); pcm->prepared = 0; pcm->running = 0; return 0; } static inline int pcm_mmap_playback_avail(struct pcm *pcm) { int avail; avail = pcm->mmap_status->hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr; if (avail < 0) avail += pcm->boundary; else if (avail > (int)pcm->boundary) avail -= pcm->boundary; return avail; } static inline int pcm_mmap_capture_avail(struct pcm *pcm) { int avail = pcm->mmap_status->hw_ptr - pcm->mmap_control->appl_ptr; if (avail < 0) avail += pcm->boundary; return avail; } int pcm_mmap_avail(struct pcm *pcm) { pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC); if (pcm->flags & PCM_IN) return pcm_mmap_capture_avail(pcm); else return pcm_mmap_playback_avail(pcm); } static void pcm_mmap_appl_forward(struct pcm *pcm, int frames) { unsigned int appl_ptr = pcm->mmap_control->appl_ptr; appl_ptr += frames; /* check for boundary wrap */ if (appl_ptr > pcm->boundary) appl_ptr -= pcm->boundary; pcm->mmap_control->appl_ptr = appl_ptr; } int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, unsigned int *frames) { unsigned int continuous, copy_frames, avail; /* return the mmap buffer */ *areas = pcm->mmap_buffer; /* and the application offset in frames */ *offset = pcm->mmap_control->appl_ptr % pcm->buffer_size; avail = pcm_mmap_avail(pcm); if (avail > pcm->buffer_size) avail = pcm->buffer_size; continuous = pcm->buffer_size - *offset; /* we can only copy frames if the are availabale and continuos */ copy_frames = *frames; if (copy_frames > avail) copy_frames = avail; if (copy_frames > continuous) copy_frames = continuous; *frames = copy_frames; return 0; } int pcm_mmap_commit(struct pcm *pcm, unsigned int offset __attribute__((unused)), unsigned int frames) { /* update the application pointer in userspace and kernel */ pcm_mmap_appl_forward(pcm, frames); pcm_sync_ptr(pcm, 0); return frames; } int pcm_avail_update(struct pcm *pcm) { pcm_sync_ptr(pcm, 0); return pcm_mmap_avail(pcm); } int pcm_state(struct pcm *pcm) { int err = pcm_sync_ptr(pcm, 0); if (err < 0) return err; return pcm->mmap_status->state; } int pcm_set_avail_min(struct pcm *pcm, int avail_min) { if ((~pcm->flags) & (PCM_MMAP | PCM_NOIRQ)) return -ENOSYS; pcm->config.avail_min = avail_min; return 0; } int pcm_wait(struct pcm *pcm, int timeout) { struct pollfd pfd; int err; pfd.fd = pcm->fd; pfd.events = POLLOUT | POLLERR | POLLNVAL; do { /* let's wait for avail or timeout */ err = poll(&pfd, 1, timeout); if (err < 0) return -errno; /* timeout ? */ if (err == 0) return 0; /* have we been interrupted ? */ if (errno == -EINTR) continue; /* check for any errors */ if (pfd.revents & (POLLERR | POLLNVAL)) { switch (pcm_state(pcm)) { case PCM_STATE_XRUN: return -EPIPE; case PCM_STATE_SUSPENDED: return -ESTRPIPE; case PCM_STATE_DISCONNECTED: return -ENODEV; default: return -EIO; } } /* poll again if fd not ready for IO */ } while (!(pfd.revents & (POLLIN | POLLOUT))); return 1; } int pcm_get_poll_fd(struct pcm *pcm) { return pcm->fd; } int pcm_mmap_transfer(struct pcm *pcm, const void *buffer, unsigned int bytes) { int err = 0, frames, avail; unsigned int offset = 0, count; if (bytes == 0) return 0; count = pcm_bytes_to_frames(pcm, bytes); while (count > 0) { /* get the available space for writing new frames */ avail = pcm_avail_update(pcm); if (avail < 0) { fprintf(stderr, "cannot determine available mmap frames"); return err; } /* start the audio if we reach the threshold */ if (!pcm->running && (pcm->buffer_size - avail) >= pcm->config.start_threshold) { if (pcm_start(pcm) < 0) { fprintf(stderr, "start error: hw 0x%x app 0x%x avail 0x%x\n", (unsigned int)pcm->mmap_status->hw_ptr, (unsigned int)pcm->mmap_control->appl_ptr, avail); return -errno; } pcm->wait_for_avail_min = 0; } /* sleep until we have space to write new frames */ if (pcm->running) { /* enable waiting for avail_min threshold when less frames than we have to write * are available. */ if (!pcm->wait_for_avail_min && (count > (unsigned int)avail)) pcm->wait_for_avail_min = 1; if (pcm->wait_for_avail_min && (avail < pcm->config.avail_min)) { int time = -1; /* disable waiting for avail_min threshold to allow small amounts of data to be * written without waiting as long as there is enough room in buffer. */ pcm->wait_for_avail_min = 0; if (pcm->flags & PCM_NOIRQ) time = (pcm->config.avail_min - avail) / pcm->noirq_frames_per_msec; err = pcm_wait(pcm, time); if (err < 0) { pcm->prepared = 0; pcm->running = 0; oops(pcm, err, "wait error: hw 0x%x app 0x%x avail 0x%x\n", (unsigned int)pcm->mmap_status->hw_ptr, (unsigned int)pcm->mmap_control->appl_ptr, avail); pcm->mmap_control->appl_ptr = 0; return err; } continue; } } frames = count; if (frames > avail) frames = avail; if (!frames) break; /* copy frames from buffer */ frames = pcm_mmap_transfer_areas(pcm, (void *)buffer, offset, frames); if (frames < 0) { fprintf(stderr, "write error: hw 0x%x app 0x%x avail 0x%x\n", (unsigned int)pcm->mmap_status->hw_ptr, (unsigned int)pcm->mmap_control->appl_ptr, avail); return frames; } offset += frames; count -= frames; } return 0; } int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count) { if ((~pcm->flags) & (PCM_OUT | PCM_MMAP)) return -ENOSYS; return pcm_mmap_transfer(pcm, (void *)data, count); } int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count) { if ((~pcm->flags) & (PCM_IN | PCM_MMAP)) return -ENOSYS; return pcm_mmap_transfer(pcm, data, count); } int pcm_ioctl(struct pcm *pcm, int request, ...) { va_list ap; void * arg; if (!pcm_is_ready(pcm)) return -1; va_start(ap, request); arg = va_arg(ap, void *); va_end(ap); return ioctl(pcm->fd, request, arg); }