| /* pcm.c |
| ** |
| ** Copyright 2011, The Android Open Source Project |
| ** |
| ** Redistribution and use in source and binary forms, with or without |
| ** modification, are permitted provided that the following conditions are met: |
| ** * Redistributions of source code must retain the above copyright |
| ** notice, this list of conditions and the following disclaimer. |
| ** * Redistributions in binary form must reproduce the above copyright |
| ** notice, this list of conditions and the following disclaimer in the |
| ** documentation and/or other materials provided with the distribution. |
| ** * Neither the name of The Android Open Source Project nor the names of |
| ** its contributors may be used to endorse or promote products derived |
| ** from this software without specific prior written permission. |
| ** |
| ** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND |
| ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| ** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE |
| ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| ** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH |
| ** DAMAGE. |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <fcntl.h> |
| #include <stdarg.h> |
| #include <string.h> |
| #include <errno.h> |
| #include <unistd.h> |
| #include <poll.h> |
| |
| #include <sys/ioctl.h> |
| #include <sys/mman.h> |
| #include <sys/time.h> |
| #include <time.h> |
| #include <limits.h> |
| |
| #include <linux/ioctl.h> |
| |
| #ifndef __force |
| #define __force |
| #endif |
| |
| #ifndef __bitwise |
| #define __bitwise |
| #endif |
| |
| #ifndef __user |
| #define __user |
| #endif |
| |
| #include <sound/asound.h> |
| |
| #include <tinyalsa/pcm.h> |
| #include <tinyalsa/limits.h> |
| #include "pcm_io.h" |
| #include "snd_card_plugin.h" |
| |
| #ifndef PARAM_MAX |
| #define PARAM_MAX SNDRV_PCM_HW_PARAM_LAST_INTERVAL |
| #endif /* PARAM_MAX */ |
| |
| #ifndef SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP |
| #define SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP (1<<2) |
| #endif /* SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP */ |
| |
| /* 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 const struct snd_interval *param_get_interval(const struct snd_pcm_hw_params *p, int n) |
| { |
| return &(p->intervals[n - SNDRV_PCM_HW_PARAM_FIRST_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(const struct snd_pcm_hw_params *p, int n) |
| { |
| if (param_is_interval(n)) { |
| const struct snd_interval *i = param_get_interval(p, n); |
| return i->min; |
| } |
| return 0; |
| } |
| |
| static unsigned int param_get_max(const struct snd_pcm_hw_params *p, int n) |
| { |
| if (param_is_interval(n)) { |
| const struct snd_interval *i = param_get_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; |
| } |
| |
| static unsigned int pcm_format_to_alsa(enum pcm_format format) |
| { |
| switch (format) { |
| |
| case PCM_FORMAT_S8: |
| return SNDRV_PCM_FORMAT_S8; |
| |
| default: |
| case PCM_FORMAT_S16_LE: |
| return SNDRV_PCM_FORMAT_S16_LE; |
| case PCM_FORMAT_S16_BE: |
| return SNDRV_PCM_FORMAT_S16_BE; |
| |
| case PCM_FORMAT_S24_LE: |
| return SNDRV_PCM_FORMAT_S24_LE; |
| case PCM_FORMAT_S24_BE: |
| return SNDRV_PCM_FORMAT_S24_BE; |
| |
| case PCM_FORMAT_S24_3LE: |
| return SNDRV_PCM_FORMAT_S24_3LE; |
| case PCM_FORMAT_S24_3BE: |
| return SNDRV_PCM_FORMAT_S24_3BE; |
| |
| case PCM_FORMAT_S32_LE: |
| return SNDRV_PCM_FORMAT_S32_LE; |
| case PCM_FORMAT_S32_BE: |
| return SNDRV_PCM_FORMAT_S32_BE; |
| |
| case PCM_FORMAT_FLOAT_LE: |
| return SNDRV_PCM_FORMAT_FLOAT_LE; |
| case PCM_FORMAT_FLOAT_BE: |
| return SNDRV_PCM_FORMAT_FLOAT_BE; |
| }; |
| } |
| |
| #define PCM_ERROR_MAX 128 |
| |
| /** A PCM handle. |
| * @ingroup libtinyalsa-pcm |
| */ |
| struct pcm { |
| /** The PCM's file descriptor */ |
| int fd; |
| /** Flags that were passed to @ref pcm_open */ |
| unsigned int flags; |
| /** The number of (under/over)runs that have occured */ |
| int xruns; |
| /** Size of the buffer */ |
| unsigned int buffer_size; |
| /** The boundary for ring buffer pointers */ |
| unsigned long boundary; |
| /** Description of the last error that occured */ |
| char error[PCM_ERROR_MAX]; |
| /** Configuration that was passed to @ref pcm_open */ |
| 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; |
| /** The delay of the PCM, in terms of frames */ |
| long pcm_delay; |
| /** The subdevice corresponding to the PCM */ |
| unsigned int subdevice; |
| /** Pointer to the pcm ops, either hw or plugin */ |
| const struct pcm_ops *ops; |
| /** Private data for pcm_hw or pcm_plugin */ |
| void *data; |
| /** Pointer to the pcm node from snd card definition */ |
| struct snd_node *snd_node; |
| }; |
| |
| 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 (e) |
| snprintf(pcm->error + sz, PCM_ERROR_MAX - sz, |
| ": %s", strerror(e)); |
| return -1; |
| } |
| |
| /** Gets the buffer size of the PCM. |
| * @param pcm A PCM handle. |
| * @return The buffer size of the PCM. |
| * @ingroup libtinyalsa-pcm |
| */ |
| unsigned int pcm_get_buffer_size(const struct pcm *pcm) |
| { |
| return pcm->buffer_size; |
| } |
| |
| /** Gets the channel count of the PCM. |
| * @param pcm A PCM handle. |
| * @return The channel count of the PCM. |
| * @ingroup libtinyalsa-pcm |
| */ |
| unsigned int pcm_get_channels(const struct pcm *pcm) |
| { |
| return pcm->config.channels; |
| } |
| |
| /** Gets the PCM configuration. |
| * @param pcm A PCM handle. |
| * @return The PCM configuration. |
| * This function only returns NULL if |
| * @p pcm is NULL. |
| * @ingroup libtinyalsa-pcm |
| * */ |
| const struct pcm_config * pcm_get_config(const struct pcm *pcm) |
| { |
| if (pcm == NULL) |
| return NULL; |
| return &pcm->config; |
| } |
| |
| /** Gets the rate of the PCM. |
| * The rate is given in frames per second. |
| * @param pcm A PCM handle. |
| * @return The rate of the PCM. |
| * @ingroup libtinyalsa-pcm |
| */ |
| unsigned int pcm_get_rate(const struct pcm *pcm) |
| { |
| return pcm->config.rate; |
| } |
| |
| /** Gets the format of the PCM. |
| * @param pcm A PCM handle. |
| * @return The format of the PCM. |
| * @ingroup libtinyalsa-pcm |
| */ |
| enum pcm_format pcm_get_format(const struct pcm *pcm) |
| { |
| return pcm->config.format; |
| } |
| |
| /** Gets the file descriptor of the PCM. |
| * Useful for extending functionality of the PCM when needed. |
| * @param pcm A PCM handle. |
| * @return The file descriptor of the PCM. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_get_file_descriptor(const struct pcm *pcm) |
| { |
| return pcm->fd; |
| } |
| |
| /** Gets the error message for the last error that occured. |
| * If no error occured and this function is called, the results are undefined. |
| * @param pcm A PCM handle. |
| * @return The error message of the last error that occured. |
| * @ingroup libtinyalsa-pcm |
| */ |
| const char* pcm_get_error(const struct pcm *pcm) |
| { |
| return pcm->error; |
| } |
| |
| /** Sets the PCM configuration. |
| * @param pcm A PCM handle. |
| * @param config The configuration to use for the |
| * PCM. This parameter may be NULL, in which case |
| * the default configuration is used. |
| * @returns Zero on success, a negative errno value |
| * on failure. |
| * @ingroup libtinyalsa-pcm |
| * */ |
| int pcm_set_config(struct pcm *pcm, const struct pcm_config *config) |
| { |
| if (pcm == NULL) |
| return -EFAULT; |
| else if (config == NULL) { |
| config = &pcm->config; |
| pcm->config.channels = 2; |
| pcm->config.rate = 48000; |
| pcm->config.period_size = 1024; |
| pcm->config.period_count = 4; |
| pcm->config.format = PCM_FORMAT_S16_LE; |
| pcm->config.start_threshold = config->period_count * config->period_size; |
| pcm->config.stop_threshold = config->period_count * config->period_size; |
| pcm->config.silence_threshold = 0; |
| pcm->config.silence_size = 0; |
| } else |
| pcm->config = *config; |
| |
| struct snd_pcm_hw_params params; |
| param_init(¶ms); |
| param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_FORMAT, |
| pcm_format_to_alsa(config->format)); |
| param_set_min(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, config->period_size); |
| 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 (pcm->flags & PCM_NOIRQ) { |
| |
| if (!(pcm->flags & PCM_MMAP)) { |
| oops(pcm, EINVAL, "noirq only currently supported with mmap()."); |
| return -EINVAL; |
| } |
| |
| params.flags |= SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP; |
| pcm->noirq_frames_per_msec = config->rate / 1000; |
| } |
| |
| if (pcm->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 (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_HW_PARAMS, ¶ms)) { |
| int errno_copy = errno; |
| oops(pcm, errno, "cannot set hw params"); |
| return -errno_copy; |
| } |
| |
| /* get our refined hw_params */ |
| pcm->config.period_size = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE); |
| pcm->config.period_count = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS); |
| pcm->buffer_size = config->period_count * config->period_size; |
| |
| if (pcm->flags & PCM_MMAP) { |
| pcm->mmap_buffer = pcm->ops->mmap(pcm->data, NULL, pcm_frames_to_bytes(pcm, pcm->buffer_size), |
| PROT_READ | PROT_WRITE, MAP_SHARED, 0); |
| if (pcm->mmap_buffer == MAP_FAILED) { |
| int errno_copy = errno; |
| oops(pcm, errno, "failed to mmap buffer %d bytes\n", |
| pcm_frames_to_bytes(pcm, pcm->buffer_size)); |
| return -errno_copy; |
| } |
| } |
| |
| struct snd_pcm_sw_params sparams; |
| memset(&sparams, 0, sizeof(sparams)); |
| sparams.tstamp_mode = SNDRV_PCM_TSTAMP_ENABLE; |
| sparams.period_step = 1; |
| sparams.avail_min = config->period_size; |
| |
| 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; |
| |
| sparams.xfer_align = config->period_size / 2; /* needed for old kernels */ |
| sparams.silence_size = config->silence_size; |
| sparams.silence_threshold = config->silence_threshold; |
| |
| if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) { |
| int errno_copy = errno; |
| oops(pcm, errno, "cannot set sw params"); |
| return -errno_copy; |
| } |
| |
| pcm->boundary = sparams.boundary; |
| return 0; |
| } |
| |
| /** Gets the subdevice on which the pcm has been opened. |
| * @param pcm A PCM handle. |
| * @return The subdevice on which the pcm has been opened */ |
| unsigned int pcm_get_subdevice(const struct pcm *pcm) |
| { |
| return pcm->subdevice; |
| } |
| |
| /** Determines the number of bits occupied by a @ref pcm_format. |
| * @param format A PCM format. |
| * @return The number of bits associated with @p format |
| * @ingroup libtinyalsa-pcm |
| */ |
| unsigned int pcm_format_to_bits(enum pcm_format format) |
| { |
| switch (format) { |
| case PCM_FORMAT_S32_LE: |
| case PCM_FORMAT_S32_BE: |
| case PCM_FORMAT_S24_LE: |
| case PCM_FORMAT_S24_BE: |
| case PCM_FORMAT_FLOAT_LE: |
| case PCM_FORMAT_FLOAT_BE: |
| return 32; |
| case PCM_FORMAT_S24_3LE: |
| case PCM_FORMAT_S24_3BE: |
| return 24; |
| default: |
| case PCM_FORMAT_S16_LE: |
| case PCM_FORMAT_S16_BE: |
| return 16; |
| case PCM_FORMAT_S8: |
| return 8; |
| }; |
| } |
| |
| /** Determines how many frames of a PCM can fit into a number of bytes. |
| * @param pcm A PCM handle. |
| * @param bytes The number of bytes. |
| * @return The number of frames that may fit into @p bytes |
| * @ingroup libtinyalsa-pcm |
| */ |
| unsigned int pcm_bytes_to_frames(const struct pcm *pcm, unsigned int bytes) |
| { |
| return bytes / (pcm->config.channels * |
| (pcm_format_to_bits(pcm->config.format) >> 3)); |
| } |
| |
| /** Determines how many bytes are occupied by a number of frames of a PCM. |
| * @param pcm A PCM handle. |
| * @param frames The number of frames of a PCM. |
| * @return The bytes occupied by @p frames. |
| * @ingroup libtinyalsa-pcm |
| */ |
| unsigned int pcm_frames_to_bytes(const 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 == NULL) { |
| /* status and control are mmapped */ |
| if (flags & SNDRV_PCM_SYNC_PTR_HWSYNC) { |
| if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_HWSYNC) == -1) { |
| return oops(pcm, errno, "failed to sync hardware pointer"); |
| } |
| } |
| } else { |
| pcm->sync_ptr->flags = flags; |
| if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_SYNC_PTR, |
| pcm->sync_ptr) < 0) { |
| return oops(pcm, errno, "failed to sync mmap ptr"); |
| } |
| } |
| |
| return 0; |
| } |
| |
| int pcm_state(struct pcm *pcm) |
| { |
| // Update the state only. Do not sync HW sync. |
| int err = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL | SNDRV_PCM_SYNC_PTR_AVAIL_MIN); |
| if (err < 0) |
| return err; |
| |
| return pcm->mmap_status->state; |
| } |
| |
| 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 = pcm->ops->mmap(pcm->data, NULL, page_size, PROT_READ, MAP_SHARED, |
| 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 = pcm->ops->mmap(pcm->data, NULL, page_size, PROT_READ | PROT_WRITE, |
| MAP_SHARED, SNDRV_PCM_MMAP_OFFSET_CONTROL); |
| if (pcm->mmap_control == MAP_FAILED) |
| pcm->mmap_control = NULL; |
| if (!pcm->mmap_control) { |
| pcm->ops->munmap(pcm->data, pcm->mmap_status, page_size); |
| pcm->mmap_status = NULL; |
| goto mmap_error; |
| } |
| |
| 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; |
| |
| 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) |
| pcm->ops->munmap(pcm->data, pcm->mmap_status, page_size); |
| if (pcm->mmap_control) |
| pcm->ops->munmap(pcm->data, pcm->mmap_control, page_size); |
| } |
| pcm->mmap_status = NULL; |
| pcm->mmap_control = NULL; |
| } |
| |
| static struct pcm bad_pcm = { |
| .fd = -1, |
| }; |
| |
| /** Gets the hardware parameters of a PCM, without created a PCM handle. |
| * @param card The card of the PCM. |
| * The default card is zero. |
| * @param device The device of the PCM. |
| * The default device is zero. |
| * @param flags Specifies whether the PCM is an input or output. |
| * May be one of the following: |
| * - @ref PCM_IN |
| * - @ref PCM_OUT |
| * @return On success, the hardware parameters of the PCM; on failure, NULL. |
| * @ingroup libtinyalsa-pcm |
| */ |
| struct pcm_params *pcm_params_get(unsigned int card, unsigned int device, |
| unsigned int flags) |
| { |
| struct snd_pcm_hw_params *params; |
| void *snd_node = NULL, *data; |
| const struct pcm_ops *ops; |
| int fd; |
| |
| ops = &hw_ops; |
| fd = ops->open(card, device, flags, &data, snd_node); |
| |
| #ifdef TINYALSA_USES_PLUGINS |
| if (fd < 0) { |
| int pcm_type; |
| snd_node = snd_utils_open_pcm(card, device); |
| pcm_type = snd_utils_get_node_type(snd_node); |
| if (!snd_node || pcm_type != SND_NODE_TYPE_PLUGIN) { |
| fprintf(stderr, "no device (hw/plugin) for card(%u), device(%u)", |
| card, device); |
| goto err_open; |
| } |
| ops = &plug_ops; |
| fd = ops->open(card, device, flags, &data, snd_node); |
| } |
| #endif |
| if (fd < 0) { |
| fprintf(stderr, "cannot open card(%d) device (%d): %s\n", |
| card, device, strerror(errno)); |
| goto err_open; |
| } |
| |
| params = calloc(1, sizeof(struct snd_pcm_hw_params)); |
| if (!params) |
| goto err_calloc; |
| |
| param_init(params); |
| if (ops->ioctl(data, SNDRV_PCM_IOCTL_HW_REFINE, params)) { |
| fprintf(stderr, "SNDRV_PCM_IOCTL_HW_REFINE error (%d)\n", errno); |
| goto err_hw_refine; |
| } |
| |
| #ifdef TINYALSA_USES_PLUGINS |
| if (snd_node) |
| snd_utils_close_dev_node(snd_node); |
| #endif |
| ops->close(data); |
| |
| return (struct pcm_params *)params; |
| |
| err_hw_refine: |
| free(params); |
| err_calloc: |
| #ifdef TINYALSA_USES_PLUGINS |
| if (snd_node) |
| snd_utils_close_dev_node(snd_node); |
| #endif |
| ops->close(data); |
| err_open: |
| return NULL; |
| } |
| |
| /** Frees the hardware parameters returned by @ref pcm_params_get. |
| * @param pcm_params Hardware parameters of a PCM. |
| * May be NULL. |
| * @ingroup libtinyalsa-pcm |
| */ |
| 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; |
| } |
| } |
| |
| /** Gets a mask from a PCM's hardware parameters. |
| * @param pcm_params A PCM's hardware parameters. |
| * @param param The parameter to get. |
| * @return If @p pcm_params is NULL or @p param is not a mask, NULL is returned. |
| * Otherwise, the mask associated with @p param is returned. |
| * @ingroup libtinyalsa-pcm |
| */ |
| const struct pcm_mask *pcm_params_get_mask(const 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 (const struct pcm_mask *)param_to_mask(params, p); |
| } |
| |
| /** Get the minimum of a specified PCM parameter. |
| * @param pcm_params A PCM parameters structure. |
| * @param param The specified parameter to get the minimum of. |
| * @returns On success, the parameter minimum. |
| * On failure, zero. |
| */ |
| unsigned int pcm_params_get_min(const 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); |
| } |
| |
| /** Get the maximum of a specified PCM parameter. |
| * @param pcm_params A PCM parameters structure. |
| * @param param The specified parameter to get the maximum of. |
| * @returns On success, the parameter maximum. |
| * On failure, zero. |
| */ |
| unsigned int pcm_params_get_max(const struct pcm_params *pcm_params, |
| enum pcm_param param) |
| { |
| const struct snd_pcm_hw_params *params = (const 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); |
| } |
| |
| static int pcm_mask_test(const 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(const 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) |
| { |
| const 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); |
| } |
| |
| /** Closes a PCM returned by @ref pcm_open. |
| * @param pcm A PCM returned by @ref pcm_open. |
| * May not be NULL. |
| * @return Always returns zero. |
| * @ingroup libtinyalsa-pcm |
| */ |
| 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); |
| pcm->ops->munmap(pcm->data, pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); |
| } |
| |
| snd_utils_close_dev_node(pcm->snd_node); |
| pcm->ops->close(pcm->data); |
| pcm->buffer_size = 0; |
| pcm->fd = -1; |
| free(pcm); |
| return 0; |
| } |
| |
| /** Opens a PCM by it's name. |
| * @param name The name of the PCM. |
| * The name is given in the format: <i>hw</i>:<b>card</b>,<b>device</b> |
| * @param flags Specify characteristics and functionality about the pcm. |
| * May be a bitwise AND of the following: |
| * - @ref PCM_IN |
| * - @ref PCM_OUT |
| * - @ref PCM_MMAP |
| * - @ref PCM_NOIRQ |
| * - @ref PCM_MONOTONIC |
| * @param config The hardware and software parameters to open the PCM with. |
| * @returns A PCM structure. |
| * If an error occurs, the pointer of bad_pcm is returned. |
| * Otherwise, it returns the pointer of PCM object. |
| * Client code should check that the PCM opened properly by calling @ref pcm_is_ready. |
| * If @ref pcm_is_ready returns false, check @ref pcm_get_error for more information. |
| * @ingroup libtinyalsa-pcm |
| */ |
| struct pcm *pcm_open_by_name(const char *name, |
| unsigned int flags, |
| const struct pcm_config *config) |
| { |
| unsigned int card, device; |
| if (name[0] != 'h' || name[1] != 'w' || name[2] != ':') { |
| oops(&bad_pcm, 0, "name format is not matched"); |
| return &bad_pcm; |
| } else if (sscanf(&name[3], "%u,%u", &card, &device) != 2) { |
| oops(&bad_pcm, 0, "name format is not matched"); |
| return &bad_pcm; |
| } |
| return pcm_open(card, device, flags, config); |
| } |
| |
| /** Opens a PCM. |
| * @param card The card that the pcm belongs to. |
| * The default card is zero. |
| * @param device The device that the pcm belongs to. |
| * The default device is zero. |
| * @param flags Specify characteristics and functionality about the pcm. |
| * May be a bitwise AND of the following: |
| * - @ref PCM_IN |
| * - @ref PCM_OUT |
| * - @ref PCM_MMAP |
| * - @ref PCM_NOIRQ |
| * - @ref PCM_MONOTONIC |
| * @param config The hardware and software parameters to open the PCM with. |
| * @returns A PCM structure. |
| * If an error occurs, the pointer of bad_pcm is returned. |
| * Otherwise, it returns the pointer of PCM object. |
| * Client code should check that the PCM opened properly by calling @ref pcm_is_ready. |
| * If @ref pcm_is_ready returns false, check @ref pcm_get_error for more information. |
| * @ingroup libtinyalsa-pcm |
| */ |
| struct pcm *pcm_open(unsigned int card, unsigned int device, |
| unsigned int flags, const struct pcm_config *config) |
| { |
| struct pcm *pcm; |
| struct snd_pcm_info info; |
| int rc; |
| |
| pcm = calloc(1, sizeof(struct pcm)); |
| if (!pcm) { |
| oops(&bad_pcm, ENOMEM, "can't allocate PCM object"); |
| return &bad_pcm; |
| } |
| |
| /* Default to hw_ops, attemp plugin open only if hw (/dev/snd/pcm*) open fails */ |
| pcm->ops = &hw_ops; |
| pcm->fd = pcm->ops->open(card, device, flags, &pcm->data, NULL); |
| |
| #ifdef TINYALSA_USES_PLUGINS |
| if (pcm->fd < 0) { |
| int pcm_type; |
| pcm->snd_node = snd_utils_open_pcm(card, device); |
| pcm_type = snd_utils_get_node_type(pcm->snd_node); |
| if (!pcm->snd_node || pcm_type != SND_NODE_TYPE_PLUGIN) { |
| oops(&bad_pcm, ENODEV, "no device (hw/plugin) for card(%u), device(%u)", |
| card, device); |
| goto fail_close_dev_node; |
| } |
| pcm->ops = &plug_ops; |
| pcm->fd = pcm->ops->open(card, device, flags, &pcm->data, pcm->snd_node); |
| } |
| #endif |
| if (pcm->fd < 0) { |
| oops(&bad_pcm, errno, "cannot open device (%u) for card (%u)", |
| device, card); |
| goto fail_close_dev_node; |
| } |
| |
| pcm->flags = flags; |
| |
| if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_INFO, &info)) { |
| oops(&bad_pcm, errno, "cannot get info"); |
| goto fail_close; |
| } |
| pcm->subdevice = info.subdevice; |
| |
| if (pcm_set_config(pcm, config) != 0) |
| goto fail_close; |
| |
| rc = pcm_hw_mmap_status(pcm); |
| if (rc < 0) { |
| oops(&bad_pcm, errno, "mmap status failed"); |
| goto fail; |
| } |
| |
| #ifdef SNDRV_PCM_IOCTL_TTSTAMP |
| if (pcm->flags & PCM_MONOTONIC) { |
| int arg = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC; |
| rc = pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_TTSTAMP, &arg); |
| if (rc < 0) { |
| oops(&bad_pcm, errno, "cannot set timestamp type"); |
| goto fail; |
| } |
| } |
| #endif |
| |
| pcm->xruns = 0; |
| return pcm; |
| |
| fail: |
| pcm_hw_munmap_status(pcm); |
| if (flags & PCM_MMAP) |
| pcm->ops->munmap(pcm->data, pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); |
| fail_close: |
| pcm->ops->close(pcm->data); |
| fail_close_dev_node: |
| #ifdef TINYALSA_USES_PLUGINS |
| if (pcm->snd_node) |
| snd_utils_close_dev_node(pcm->snd_node); |
| #endif |
| free(pcm); |
| return &bad_pcm; |
| } |
| |
| /** Checks if a PCM file has been opened without error. |
| * @param pcm A PCM handle. |
| * May be NULL. |
| * @return If a PCM's file descriptor is not valid or the pointer is NULL, it returns zero. |
| * Otherwise, the function returns one. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_is_ready(const struct pcm *pcm) |
| { |
| if (pcm != NULL) { |
| return pcm->fd >= 0; |
| } |
| return 0; |
| } |
| |
| /** Links two PCMs. |
| * After this function is called, the two PCMs will prepare, start and stop in sync (at the same time). |
| * If an error occurs, the error message will be written to @p pcm1. |
| * @param pcm1 A PCM handle. |
| * @param pcm2 Another PCM handle. |
| * @return On success, zero; on failure, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_link(struct pcm *pcm1, struct pcm *pcm2) |
| { |
| int err = ioctl(pcm1->fd, SNDRV_PCM_IOCTL_LINK, pcm2->fd); |
| if (err == -1) { |
| return oops(pcm1, errno, "cannot link PCM"); |
| } |
| return 0; |
| } |
| |
| /** Unlinks a PCM. |
| * @see @ref pcm_link |
| * @param pcm A PCM handle. |
| * @return On success, zero; on failure, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_unlink(struct pcm *pcm) |
| { |
| int err = ioctl(pcm->fd, SNDRV_PCM_IOCTL_UNLINK); |
| if (err == -1) { |
| return oops(pcm, errno, "cannot unlink PCM"); |
| } |
| return 0; |
| } |
| |
| /** Prepares a PCM, if it has not been prepared already. |
| * @param pcm A PCM handle. |
| * @return On success, zero; on failure, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_prepare(struct pcm *pcm) |
| { |
| if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_PREPARE) < 0) |
| return oops(pcm, errno, "cannot prepare channel"); |
| |
| /* get appl_ptr and avail_min from kernel */ |
| pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL|SNDRV_PCM_SYNC_PTR_AVAIL_MIN); |
| |
| return 0; |
| } |
| |
| /** Starts a PCM. |
| * @param pcm A PCM handle. |
| * @return On success, zero; on failure, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_start(struct pcm *pcm) |
| { |
| if (pcm_state(pcm) == PCM_STATE_SETUP && pcm_prepare(pcm) != 0) { |
| return -1; |
| } |
| |
| /* set appl_ptr and avail_min in kernel */ |
| if (pcm_sync_ptr(pcm, 0) < 0) |
| return -1; |
| |
| if (pcm->mmap_status->state != PCM_STATE_RUNNING) { |
| if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_START) < 0) |
| return oops(pcm, errno, "cannot start channel"); |
| } |
| |
| return 0; |
| } |
| |
| /** Stops a PCM. |
| * @param pcm A PCM handle. |
| * @return On success, zero; on failure, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_stop(struct pcm *pcm) |
| { |
| if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_DROP) < 0) |
| return oops(pcm, errno, "cannot stop channel"); |
| |
| return 0; |
| } |
| |
| static inline long pcm_mmap_playback_avail(struct pcm *pcm) |
| { |
| long avail = pcm->mmap_status->hw_ptr + (unsigned long) pcm->buffer_size - |
| pcm->mmap_control->appl_ptr; |
| |
| if (avail < 0) { |
| avail += pcm->boundary; |
| } else if ((unsigned long) avail >= pcm->boundary) { |
| avail -= pcm->boundary; |
| } |
| |
| return avail; |
| } |
| |
| static inline long pcm_mmap_capture_avail(struct pcm *pcm) |
| { |
| long 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 (int) pcm_mmap_capture_avail(pcm); |
| } else { |
| return (int) pcm_mmap_playback_avail(pcm); |
| } |
| } |
| |
| static void pcm_mmap_appl_forward(struct pcm *pcm, int frames) |
| { |
| unsigned long 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 available and continuos */ |
| copy_frames = *frames; |
| if (copy_frames > avail) |
| copy_frames = avail; |
| if (copy_frames > continuous) |
| copy_frames = continuous; |
| *frames = copy_frames; |
| |
| return 0; |
| } |
| |
| 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; |
| } |
| |
| int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames) |
| { |
| int ret; |
| |
| /* not used */ |
| (void) offset; |
| |
| /* update the application pointer in userspace and kernel */ |
| pcm_mmap_appl_forward(pcm, frames); |
| ret = pcm_sync_ptr(pcm, 0); |
| if (ret != 0){ |
| printf("%d\n", ret); |
| return ret; |
| } |
| |
| return frames; |
| } |
| |
| 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 (pcm_mmap_avail(pcm) && size) { |
| 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_poll_fd(struct pcm *pcm) |
| { |
| return pcm->fd; |
| } |
| |
| int pcm_avail_update(struct pcm *pcm) |
| { |
| pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL|SNDRV_PCM_SYNC_PTR_AVAIL_MIN); |
| return pcm_mmap_avail(pcm); |
| } |
| |
| /** Returns available frames in pcm buffer and corresponding time stamp. |
| * The clock is CLOCK_MONOTONIC if flag @ref PCM_MONOTONIC was specified in @ref pcm_open, |
| * otherwise the clock is CLOCK_REALTIME. |
| * For an input stream, frames available are frames ready for the application to read. |
| * For an output stream, frames available are the number of empty frames available for the application to write. |
| * @param pcm A PCM handle. |
| * @param avail The number of available frames |
| * @param tstamp The timestamp |
| * @return On success, zero is returned; on failure, negative one. |
| */ |
| int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, |
| struct timespec *tstamp) |
| { |
| int checking; |
| int tmp; |
| |
| if (!pcm_is_ready(pcm)) |
| return -1; |
| |
| checking = 0; |
| |
| again: |
| |
| tmp = pcm_avail_update(pcm); |
| if (tmp < 0) |
| return tmp; /* error */ |
| |
| if (checking && (unsigned int) tmp == *avail) |
| return 0; |
| |
| *avail = (unsigned int) tmp; |
| *tstamp = pcm->mmap_status->tstamp; |
| |
| /* |
| * When status is mmapped, get avail again to ensure |
| * valid timestamp. |
| */ |
| if (!pcm->sync_ptr) { |
| checking = 1; |
| goto again; |
| } |
| |
| /* SYNC_PTR ioctl was used, no need to check avail */ |
| return 0; |
| } |
| |
| /** Waits for frames to be available for read or write operations. |
| * @param pcm A PCM handle. |
| * @param timeout The maximum amount of time to wait for, in terms of milliseconds. |
| * @returns If frames became available, one is returned. |
| * If a timeout occured, zero is returned. |
| * If an error occured, a negative number is returned. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_wait(struct pcm *pcm, int timeout) |
| { |
| struct pollfd pfd; |
| int err; |
| |
| pfd.fd = pcm->fd; |
| pfd.events = POLLIN | POLLOUT | POLLERR | POLLNVAL; |
| |
| do { |
| /* let's wait for avail or timeout */ |
| err = pcm->ops->poll(pcm->data, &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; |
| } |
| |
| /* |
| * Transfer data to/from mmapped buffer. This imitates the |
| * behavior of read/write system calls. |
| * |
| * However, this doesn't seems to offer any advantage over |
| * the read/write syscalls. Should it be removed? |
| */ |
| static int pcm_mmap_transfer(struct pcm *pcm, void *buffer, unsigned int frames) |
| { |
| int is_playback; |
| |
| int state; |
| unsigned int avail; |
| unsigned int user_offset = 0; |
| |
| int err; |
| int transferred_frames; |
| |
| is_playback = !(pcm->flags & PCM_IN); |
| |
| if (frames == 0) |
| return 0; |
| |
| /* update hardware pointer and get state */ |
| err = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC | |
| SNDRV_PCM_SYNC_PTR_APPL | |
| SNDRV_PCM_SYNC_PTR_AVAIL_MIN); |
| if (err == -1) |
| return -1; |
| state = pcm->mmap_status->state; |
| |
| /* |
| * If frames < start_threshold, wait indefinitely. |
| * Another thread may start capture |
| */ |
| if (!is_playback && state == PCM_STATE_PREPARED && |
| frames >= pcm->config.start_threshold) { |
| if (pcm_start(pcm) < 0) { |
| return -1; |
| } |
| } |
| |
| while (frames) { |
| avail = pcm_mmap_avail(pcm); |
| |
| if (!avail) { |
| if (pcm->flags & PCM_NONBLOCK) { |
| errno = EAGAIN; |
| break; |
| } |
| |
| /* wait for interrupt */ |
| err = pcm_wait(pcm, -1); |
| if (err < 0) { |
| errno = -err; |
| break; |
| } |
| } |
| |
| transferred_frames = pcm_mmap_transfer_areas(pcm, buffer, user_offset, frames); |
| if (transferred_frames < 0) { |
| break; |
| } |
| |
| user_offset += transferred_frames; |
| frames -= transferred_frames; |
| |
| /* start playback if written >= start_threshold */ |
| if (is_playback && state == PCM_STATE_PREPARED && |
| pcm->buffer_size - avail >= pcm->config.start_threshold) { |
| if (pcm_start(pcm) < 0) { |
| break; |
| } |
| } |
| } |
| |
| return user_offset ? (int) user_offset : -1; |
| } |
| |
| int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count) |
| { |
| if ((~pcm->flags) & (PCM_OUT | PCM_MMAP)) |
| return -EINVAL; |
| |
| unsigned int frames = pcm_bytes_to_frames(pcm, count); |
| int res = pcm_writei(pcm, (void *) data, frames); |
| |
| if (res < 0) { |
| return res; |
| } |
| |
| return (unsigned int) res == frames ? 0 : -EIO; |
| } |
| |
| int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count) |
| { |
| if ((~pcm->flags) & (PCM_IN | PCM_MMAP)) |
| return -EINVAL; |
| |
| unsigned int frames = pcm_bytes_to_frames(pcm, count); |
| int res = pcm_readi(pcm, data, frames); |
| |
| if (res < 0) { |
| return res; |
| } |
| |
| return (unsigned int) res == frames ? 0 : -EIO; |
| } |
| |
| /* Returns current read/write position in the mmap buffer with associated time stamp. */ |
| int pcm_mmap_get_hw_ptr(struct pcm* pcm, unsigned int *hw_ptr, struct timespec *tstamp) |
| { |
| int rc; |
| |
| if (pcm == NULL || hw_ptr == NULL || tstamp == NULL) |
| return oops(pcm, EINVAL, "pcm %p, hw_ptr %p, tstamp %p", pcm, hw_ptr, tstamp); |
| |
| if (!pcm_is_ready(pcm)) |
| return oops(pcm, errno, "pcm_is_ready failed"); |
| |
| rc = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC); |
| if (rc < 0) |
| return oops(pcm, errno, "pcm_sync_ptr failed"); |
| |
| if (pcm->mmap_status == NULL) |
| return oops(pcm, EINVAL, "pcm %p, mmap_status is NULL", pcm); |
| |
| if ((pcm->mmap_status->state != PCM_STATE_RUNNING) && |
| (pcm->mmap_status->state != PCM_STATE_DRAINING)) |
| return oops(pcm, ENOSYS, "invalid stream state %d", pcm->mmap_status->state); |
| |
| *tstamp = pcm->mmap_status->tstamp; |
| if (tstamp->tv_sec == 0 && tstamp->tv_nsec == 0) |
| return oops(pcm, errno, "invalid time stamp"); |
| |
| *hw_ptr = pcm->mmap_status->hw_ptr; |
| |
| return 0; |
| } |
| |
| static int pcm_rw_transfer(struct pcm *pcm, void *data, unsigned int frames) |
| { |
| int is_playback; |
| |
| struct snd_xferi transfer; |
| int res; |
| |
| is_playback = !(pcm->flags & PCM_IN); |
| |
| transfer.buf = data; |
| transfer.frames = frames; |
| transfer.result = 0; |
| |
| res = pcm->ops->ioctl(pcm->data, is_playback |
| ? SNDRV_PCM_IOCTL_WRITEI_FRAMES |
| : SNDRV_PCM_IOCTL_READI_FRAMES, &transfer); |
| |
| return res == 0 ? (int) transfer.result : -1; |
| } |
| |
| static int pcm_generic_transfer(struct pcm *pcm, void *data, |
| unsigned int frames) |
| { |
| int res; |
| |
| #if UINT_MAX > TINYALSA_FRAMES_MAX |
| if (frames > TINYALSA_FRAMES_MAX) |
| return -EINVAL; |
| #endif |
| if (frames > INT_MAX) |
| return -EINVAL; |
| |
| if (pcm_state(pcm) == PCM_STATE_SETUP && pcm_prepare(pcm) != 0) { |
| return -1; |
| } |
| |
| again: |
| |
| if (pcm->flags & PCM_MMAP) |
| res = pcm_mmap_transfer(pcm, data, frames); |
| else |
| res = pcm_rw_transfer(pcm, data, frames); |
| |
| if (res < 0) { |
| switch (errno) { |
| case EPIPE: |
| pcm->xruns++; |
| /* fallthrough */ |
| case ESTRPIPE: |
| /* |
| * Try to restart if we are allowed to do so. |
| * Otherwise, return error. |
| */ |
| if (pcm->flags & PCM_NORESTART || pcm_prepare(pcm)) |
| return -1; |
| goto again; |
| case EAGAIN: |
| if (pcm->flags & PCM_NONBLOCK) |
| return -1; |
| /* fallthrough */ |
| default: |
| return oops(pcm, errno, "cannot read/write stream data"); |
| } |
| } |
| |
| return res; |
| } |
| |
| /** Writes audio samples to PCM. |
| * If the PCM has not been started, it is started in this function. |
| * This function is only valid for PCMs opened with the @ref PCM_OUT flag. |
| * @param pcm A PCM handle. |
| * @param data The audio sample array |
| * @param frame_count The number of frames occupied by the sample array. |
| * This value should not be greater than @ref TINYALSA_FRAMES_MAX |
| * or INT_MAX. |
| * @return On success, this function returns the number of frames written; otherwise, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_writei(struct pcm *pcm, const void *data, unsigned int frame_count) |
| { |
| if (pcm->flags & PCM_IN) |
| return -EINVAL; |
| |
| return pcm_generic_transfer(pcm, (void*) data, frame_count); |
| } |
| |
| /** Reads audio samples from PCM. |
| * If the PCM has not been started, it is started in this function. |
| * This function is only valid for PCMs opened with the @ref PCM_IN flag. |
| * @param pcm A PCM handle. |
| * @param data The audio sample array |
| * @param frame_count The number of frames occupied by the sample array. |
| * This value should not be greater than @ref TINYALSA_FRAMES_MAX |
| * or INT_MAX. |
| * @return On success, this function returns the number of frames written; otherwise, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_readi(struct pcm *pcm, void *data, unsigned int frame_count) |
| { |
| if (!(pcm->flags & PCM_IN)) |
| return -EINVAL; |
| |
| return pcm_generic_transfer(pcm, data, frame_count); |
| } |
| |
| /** Writes audio samples to PCM. |
| * If the PCM has not been started, it is started in this function. |
| * This function is only valid for PCMs opened with the @ref PCM_OUT flag. |
| * This function is not valid for PCMs opened with the @ref PCM_MMAP flag. |
| * @param pcm A PCM handle. |
| * @param data The audio sample array |
| * @param count The number of bytes occupied by the sample array. |
| * @return On success, this function returns zero; otherwise, a negative number. |
| * @deprecated |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_write(struct pcm *pcm, const void *data, unsigned int count) |
| { |
| unsigned int requested_frames = pcm_bytes_to_frames(pcm, count); |
| int ret = pcm_writei(pcm, data, requested_frames); |
| |
| if (ret < 0) |
| return ret; |
| |
| return ((unsigned int )ret == requested_frames) ? 0 : -EIO; |
| } |
| |
| /** Reads audio samples from PCM. |
| * If the PCM has not been started, it is started in this function. |
| * This function is only valid for PCMs opened with the @ref PCM_IN flag. |
| * This function is not valid for PCMs opened with the @ref PCM_MMAP flag. |
| * @param pcm A PCM handle. |
| * @param data The audio sample array |
| * @param count The number of bytes occupied by the sample array. |
| * @return On success, this function returns zero; otherwise, a negative number. |
| * @deprecated |
| * @ingroup libtinyalsa-pcm |
| */ |
| int pcm_read(struct pcm *pcm, void *data, unsigned int count) |
| { |
| unsigned int requested_frames = pcm_bytes_to_frames(pcm, count); |
| int ret = pcm_readi(pcm, data, requested_frames); |
| |
| if (ret < 0) |
| return ret; |
| |
| return ((unsigned int )ret == requested_frames) ? 0 : -EIO; |
| } |
| |
| /** Gets the delay of the PCM, in terms of frames. |
| * @param pcm A PCM handle. |
| * @returns On success, the delay of the PCM. |
| * On failure, a negative number. |
| * @ingroup libtinyalsa-pcm |
| */ |
| long pcm_get_delay(struct pcm *pcm) |
| { |
| if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DELAY, &pcm->pcm_delay) < 0) |
| return -1; |
| |
| return pcm->pcm_delay; |
| } |
| |
| // TODO: Currently in Android, there are some libraries using this function to control the driver. |
| // We should remove this function as soon as possible. |
| 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); |
| |
| // FIXME Does not handle plugins |
| return ioctl(pcm->fd, request, arg); |
| } |