diff options
Diffstat (limited to 'src/host/layer23/src/mobile/gapk_io.c')
| -rw-r--r-- | src/host/layer23/src/mobile/gapk_io.c | 547 |
1 files changed, 547 insertions, 0 deletions
diff --git a/src/host/layer23/src/mobile/gapk_io.c b/src/host/layer23/src/mobile/gapk_io.c new file mode 100644 index 00000000..cc756b06 --- /dev/null +++ b/src/host/layer23/src/mobile/gapk_io.c @@ -0,0 +1,547 @@ +/* + * GAPK (GSM Audio Pocket Knife) based audio I/O + * + * (C) 2017-2022 by Vadim Yanitskiy <axilirator@gmail.com> + * Contributions by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> + * + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <string.h> +#include <errno.h> + +#include <osmocom/core/msgb.h> +#include <osmocom/core/utils.h> + +#include <osmocom/gsm/protocol/gsm_04_08.h> +#include <osmocom/gsm/protocol/gsm_08_58.h> + +#include <osmocom/gapk/procqueue.h> +#include <osmocom/gapk/formats.h> +#include <osmocom/gapk/codecs.h> +#include <osmocom/gapk/common.h> + +#include <osmocom/bb/common/osmocom_data.h> +#include <osmocom/bb/common/ms.h> +#include <osmocom/bb/common/logging.h> + +#include <osmocom/bb/mobile/tch.h> +#include <osmocom/bb/mobile/gapk_io.h> + +/* The RAW PCM format is common for both audio source and sink */ +static const struct osmo_gapk_format_desc *rawpcm_fmt; + +static int pq_queue_tch_fb_recv(void *_state, uint8_t *out, + const uint8_t *in, unsigned int in_len) +{ + struct gapk_io_state *state = (struct gapk_io_state *)_state; + struct msgb *tch_msg; + size_t frame_len; + + /* Obtain one TCH frame from the DL buffer */ + tch_msg = msgb_dequeue_count(&state->tch_dl_fb, + &state->tch_dl_fb_len); + if (tch_msg == NULL) + return -EIO; + + /* Calculate received frame length */ + frame_len = msgb_l3len(tch_msg); + if (frame_len == 0) { + msgb_free(tch_msg); + return -EIO; + } + + /* Copy the frame bytes from message */ + memcpy(out, tch_msg->l3h, frame_len); + + /* Release memory */ + msgb_free(tch_msg); + + return frame_len; +} + +static int pq_queue_tch_fb_send(void *_state, uint8_t *out, + const uint8_t *in, unsigned int in_len) +{ + struct gapk_io_state *state = (struct gapk_io_state *)_state; + struct msgb *tch_msg; + + if (state->tch_ul_fb_len >= GAPK_ULDL_QUEUE_LIMIT) { + LOGP(DGAPK, LOGL_ERROR, "UL TCH frame buffer overflow, dropping msg\n"); + return -EOVERFLOW; + } + + /* Allocate a new message for the lower layers */ + tch_msg = msgb_alloc_headroom(in_len + 64, 64, "TCH frame"); + if (tch_msg == NULL) + return -ENOMEM; + + /* Copy the frame bytes to a new message */ + tch_msg->l2h = msgb_put(tch_msg, in_len); + memcpy(tch_msg->l2h, in, in_len); + + /* Put encoded TCH frame to the UL buffer */ + msgb_enqueue_count(&state->tch_ul_fb, tch_msg, + &state->tch_ul_fb_len); + + return 0; +} + +/** + * A custom TCH frame buffer block, which actually + * handles incoming frames from DL buffer and puts + * outgoing frames to UL buffer... + */ +static int pq_queue_tch_fb(struct osmo_gapk_pq *pq, + struct gapk_io_state *state, + bool is_src) +{ + struct osmo_gapk_pq_item *item; + unsigned int frame_len; + + LOGP(DGAPK, LOGL_DEBUG, "PQ '%s': Adding TCH frame buffer %s\n", + pq->name, is_src ? "input" : "output"); + + /* Allocate and add a new queue item */ + item = osmo_gapk_pq_add_item(pq); + if (item == NULL) + return -ENOMEM; + + /* General item type and description */ + item->type = is_src ? OSMO_GAPK_ITEM_TYPE_SOURCE : OSMO_GAPK_ITEM_TYPE_SINK; + item->cat_name = is_src ? "source" : "sink"; + item->sub_name = "tch_fb"; + + /* I/O length */ + frame_len = state->phy_fmt_desc->frame_len; + item->len_in = is_src ? 0 : frame_len; + item->len_out = is_src ? frame_len : 0; + + /* Handler and it's state */ + item->proc = is_src ? &pq_queue_tch_fb_recv : &pq_queue_tch_fb_send; + item->state = state; + + return 0; +} + +/** + * Auxiliary wrapper around format conversion block. + * Is used to perform either a conversion from the format, + * produced by encoder, to canonical, or a conversion + * from canonical format to the format expected by decoder. + */ +static int pq_queue_codec_fmt_conv(struct osmo_gapk_pq *pq, + const struct osmo_gapk_codec_desc *codec, + bool is_src) +{ + const struct osmo_gapk_format_desc *codec_fmt_desc; + + /* Get format description */ + codec_fmt_desc = osmo_gapk_fmt_get_from_type(is_src ? + codec->codec_enc_format_type : codec->codec_dec_format_type); + if (codec_fmt_desc == NULL) + return -ENOTSUP; + + /* Put format conversion block */ + return osmo_gapk_pq_queue_fmt_convert(pq, codec_fmt_desc, !is_src); +} + +/** + * Prepares the following queue (source is mic): + * + * source/alsa -> proc/codec -> proc/format -> + * -> proc/format -> sink/tch_fb + * + * The two format conversion blocks are aimed to + * convert an encoder specific format + * to a PHY specific format. + */ +static int prepare_audio_source(struct gapk_io_state *state, + const char *alsa_input_dev) +{ + struct osmo_gapk_pq *pq; + char *pq_desc; + int rc; + + LOGP(DGAPK, LOGL_DEBUG, "Prepare audio input (capture) chain\n"); + + /* Allocate a processing queue */ + pq = osmo_gapk_pq_create("pq_audio_source"); + if (pq == NULL) + return -ENOMEM; + + /* ALSA audio source */ + rc = osmo_gapk_pq_queue_alsa_input(pq, alsa_input_dev, rawpcm_fmt->frame_len); + if (rc) + goto error; + + /* Frame encoder */ + rc = osmo_gapk_pq_queue_codec(pq, state->codec_desc, 1); + if (rc) + goto error; + + /* Encoder specific format -> canonical */ + rc = pq_queue_codec_fmt_conv(pq, state->codec_desc, true); + if (rc) + goto error; + + /* Canonical -> PHY specific format */ + rc = osmo_gapk_pq_queue_fmt_convert(pq, state->phy_fmt_desc, 1); + if (rc) + goto error; + + /* TCH frame buffer sink */ + rc = pq_queue_tch_fb(pq, state, false); + if (rc) + goto error; + + /* Check composed queue in strict mode */ + rc = osmo_gapk_pq_check(pq, 1); + if (rc) + goto error; + + /* Prepare queue (allocate buffers, etc.) */ + rc = osmo_gapk_pq_prepare(pq); + if (rc) + goto error; + + /* Save pointer within MS GAPK state */ + state->pq_source = pq; + + /* Describe prepared chain */ + pq_desc = osmo_gapk_pq_describe(pq); + LOGP(DGAPK, LOGL_DEBUG, "PQ '%s': chain '%s' prepared\n", pq->name, pq_desc); + talloc_free(pq_desc); + + return 0; + +error: + talloc_free(pq); + return rc; +} + +/** + * Prepares the following queue (sink is speaker): + * + * src/tch_fb -> proc/format -> [proc/ecu] -> + * proc/format -> proc/codec -> sink/alsa + * + * The two format conversion blocks (proc/format) + * are aimed to convert a PHY specific format + * to an encoder specific format. + * + * A ECU (Error Concealment Unit) block is optionally + * added if implemented for a given codec. + */ +static int prepare_audio_sink(struct gapk_io_state *state, + const char *alsa_output_dev) +{ + struct osmo_gapk_pq *pq; + char *pq_desc; + int rc; + + LOGP(DGAPK, LOGL_DEBUG, "Prepare audio output (playback) chain\n"); + + /* Allocate a processing queue */ + pq = osmo_gapk_pq_create("pq_audio_sink"); + if (pq == NULL) + return -ENOMEM; + + /* TCH frame buffer source */ + rc = pq_queue_tch_fb(pq, state, true); + if (rc) + goto error; + + /* PHY specific format -> canonical */ + rc = osmo_gapk_pq_queue_fmt_convert(pq, state->phy_fmt_desc, 0); + if (rc) + goto error; + + /* Optional ECU (Error Concealment Unit) */ + osmo_gapk_pq_queue_ecu(pq, state->codec_desc); + + /* Canonical -> decoder specific format */ + rc = pq_queue_codec_fmt_conv(pq, state->codec_desc, false); + if (rc) + goto error; + + /* Frame decoder */ + rc = osmo_gapk_pq_queue_codec(pq, state->codec_desc, 0); + if (rc) + goto error; + + /* ALSA audio sink */ + rc = osmo_gapk_pq_queue_alsa_output(pq, alsa_output_dev, rawpcm_fmt->frame_len); + if (rc) + goto error; + + /* Check composed queue in strict mode */ + rc = osmo_gapk_pq_check(pq, 1); + if (rc) + goto error; + + /* Prepare queue (allocate buffers, etc.) */ + rc = osmo_gapk_pq_prepare(pq); + if (rc) + goto error; + + /* Save pointer within MS GAPK state */ + state->pq_sink = pq; + + /* Describe prepared chain */ + pq_desc = osmo_gapk_pq_describe(pq); + LOGP(DGAPK, LOGL_DEBUG, "PQ '%s': chain '%s' prepared\n", pq->name, pq_desc); + talloc_free(pq_desc); + + return 0; + +error: + talloc_free(pq); + return rc; +} + +/** + * Cleans up both TCH frame I/O buffers, destroys both + * processing queues (chains), and deallocates the memory. + * Should be called when a voice call is finished... + */ +void gapk_io_state_free(struct gapk_io_state *state) +{ + struct msgb *msg; + + if (state == NULL) + return; + + /* Flush TCH frame I/O buffers */ + while ((msg = msgb_dequeue(&state->tch_dl_fb))) + msgb_free(msg); + while ((msg = msgb_dequeue(&state->tch_ul_fb))) + msgb_free(msg); + + /* Destroy both audio I/O chains */ + if (state->pq_source != NULL) + osmo_gapk_pq_destroy(state->pq_source); + if (state->pq_sink != NULL) + osmo_gapk_pq_destroy(state->pq_sink); + + talloc_free(state); +} + +/** + * Picks the corresponding PHY's frame format for a given codec. + * To be used with PHYs that produce audio frames in RTP format, + * such as trxcon (GSM 05.03 libosmocoding API). + */ +static enum osmo_gapk_format_type phy_fmt_pick_rtp(enum osmo_gapk_codec_type codec) +{ + switch (codec) { + case CODEC_HR: + return FMT_RTP_HR_IETF; + case CODEC_FR: + return FMT_GSM; + case CODEC_EFR: + return FMT_RTP_EFR; + case CODEC_AMR: + return FMT_RTP_AMR; + default: + return FMT_INVALID; + } +} + +/** + * Picks the corresponding PHY's frame format for a given codec. + * To be used with PHYs that produce audio in TI Calypso format. + */ +static enum osmo_gapk_format_type phy_fmt_pick_ti(enum osmo_gapk_codec_type codec) +{ + switch (codec) { + case CODEC_HR: + return FMT_TI_HR; + case CODEC_FR: + return FMT_TI_FR; + case CODEC_EFR: + return FMT_TI_EFR; + case CODEC_AMR: /* not supported */ + default: + return FMT_INVALID; + } +} + +/** + * Allocates both TCH frame I/O buffers + * and prepares both processing queues (chains). + * Should be called when a voice call is initiated... + */ +struct gapk_io_state * +gapk_io_state_alloc(struct osmocom_ms *ms, + enum osmo_gapk_codec_type codec) +{ + const struct osmo_gapk_format_desc *phy_fmt_desc; + const struct osmo_gapk_codec_desc *codec_desc; + const struct gsm_settings *set = &ms->settings; + enum osmo_gapk_format_type phy_fmt; + struct gapk_io_state *state; + int rc = 0; + + LOGP(DGAPK, LOGL_NOTICE, "Initialize GAPK I/O\n"); + + /* Make sure that the chosen codec has description */ + codec_desc = osmo_gapk_codec_get_from_type(codec); + if (codec_desc == NULL) { + LOGP(DGAPK, LOGL_ERROR, "Invalid codec type 0x%02x\n", codec); + return NULL; + } + + /* Make sure that the chosen codec is supported */ + if (codec_desc->codec_encode == NULL || codec_desc->codec_decode == NULL) { + LOGP(DGAPK, LOGL_ERROR, + "Codec '%s' is not supported by GAPK\n", codec_desc->name); + return NULL; + } + + switch (set->tch_voice.io_format) { + case TCH_VOICE_IOF_RTP: + phy_fmt = phy_fmt_pick_rtp(codec); + break; + case TCH_VOICE_IOF_TI: + phy_fmt = phy_fmt_pick_ti(codec); + break; + default: + LOGP(DGAPK, LOGL_ERROR, "Unhandled I/O format %s\n", + tch_voice_io_format_name(set->tch_voice.io_format)); + return NULL; + } + + phy_fmt_desc = osmo_gapk_fmt_get_from_type(phy_fmt); + if (phy_fmt_desc == NULL) { + LOGP(DGAPK, LOGL_ERROR, "Failed to pick the PHY specific " + "frame format for codec '%s'\n", codec_desc->name); + return NULL; + } + + state = talloc_zero(ms, struct gapk_io_state); + if (state == NULL) { + LOGP(DGAPK, LOGL_ERROR, "Failed to allocate memory\n"); + return NULL; + } + + /* Init TCH frame I/O buffers */ + INIT_LLIST_HEAD(&state->tch_dl_fb); + INIT_LLIST_HEAD(&state->tch_ul_fb); + + /* Store the codec / format description */ + state->codec_desc = codec_desc; + state->phy_fmt_desc = phy_fmt_desc; + + /* Use gapk_io_state as talloc context for both chains */ + osmo_gapk_set_talloc_ctx(state); + + /* Prepare both source and sink chains */ + rc |= prepare_audio_source(state, set->tch_voice.alsa_input_dev); + rc |= prepare_audio_sink(state, set->tch_voice.alsa_output_dev); + + /* Fall back to ms instance */ + osmo_gapk_set_talloc_ctx(ms); + + /* If at lease one chain constructor failed */ + if (rc) { + /* Destroy both audio I/O chains */ + if (state->pq_source) + osmo_gapk_pq_destroy(state->pq_source); + if (state->pq_sink) + osmo_gapk_pq_destroy(state->pq_sink); + + /* Release the memory and return */ + talloc_free(state); + + LOGP(DGAPK, LOGL_ERROR, "Failed to initialize GAPK I/O\n"); + return NULL; + } + + LOGP(DGAPK, LOGL_NOTICE, + "GAPK I/O initialized for MS '%s', codec '%s'\n", + ms->name, codec_desc->name); + + return state; +} + +/* gapk_io_init_ms() wrapper, selecting a codec based on channel mode and rate */ +struct gapk_io_state * +gapk_io_state_alloc_mode_rate(struct osmocom_ms *ms, + enum gsm48_chan_mode ch_mode, + bool full_rate) +{ + enum osmo_gapk_codec_type codec; + + switch (ch_mode) { + case GSM48_CMODE_SPEECH_V1: /* FR or HR */ + codec = full_rate ? CODEC_FR : CODEC_HR; + break; + case GSM48_CMODE_SPEECH_EFR: + codec = CODEC_EFR; + break; + case GSM48_CMODE_SPEECH_AMR: + codec = CODEC_AMR; + break; + default: + LOGP(DGAPK, LOGL_ERROR, "Unhandled channel mode 0x%02x (%s)\n", + ch_mode, get_value_string(gsm48_chan_mode_names, ch_mode)); + return NULL; + } + + return gapk_io_state_alloc(ms, codec); +} + +/* Enqueue a Downlink TCH frame */ +void gapk_io_enqueue_dl(struct gapk_io_state *state, struct msgb *msg) +{ + if (state->tch_dl_fb_len >= GAPK_ULDL_QUEUE_LIMIT) { + LOGP(DGAPK, LOGL_ERROR, "DL TCH frame buffer overflow, dropping msg\n"); + msgb_free(msg); + return; + } + + msgb_enqueue_count(&state->tch_dl_fb, msg, + &state->tch_dl_fb_len); + + /* Decode and play a received DL TCH frame */ + osmo_gapk_pq_execute(state->pq_sink); +} + +/* Dequeue an Uplink TCH frame */ +void gapk_io_dequeue_ul(struct osmocom_ms *ms, struct gapk_io_state *state) +{ + struct msgb *msg; + + /* Record and encode an UL TCH frame */ + osmo_gapk_pq_execute(state->pq_source); + + /* Obtain one TCH frame from the UL buffer */ + msg = msgb_dequeue_count(&state->tch_ul_fb, &state->tch_ul_fb_len); + if (msg != NULL) + tch_send_msg(ms, msg); +} + +/** + * Performs basic initialization of GAPK library, + * setting the talloc root context and a logging category. + */ +static __attribute__((constructor)) void gapk_io_init(void) +{ + /* Init logging subsystem */ + osmo_gapk_log_init(DGAPK); + + /* Make RAWPCM format info easy to access */ + rawpcm_fmt = osmo_gapk_fmt_get_from_type(FMT_RAWPCM_S16LE); +} |