From c326a053cdf8a4a9ce0fb02448293b45083d553c Mon Sep 17 00:00:00 2001 From: fulup Date: Sat, 1 Jul 2017 00:22:00 +0200 Subject: Ongoing work --- ALSA-afb/Alsa-RegEvt.c | 309 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 309 insertions(+) create mode 100644 ALSA-afb/Alsa-RegEvt.c (limited to 'ALSA-afb/Alsa-RegEvt.c') diff --git a/ALSA-afb/Alsa-RegEvt.c b/ALSA-afb/Alsa-RegEvt.c new file mode 100644 index 0000000..e06cf87 --- /dev/null +++ b/ALSA-afb/Alsa-RegEvt.c @@ -0,0 +1,309 @@ +/* + * AlsaLibMapping -- provide low level interface with ALSA lib (extracted from alsa-json-gateway code) + * Copyright (C) 2015,2016,2017, Fulup Ar Foll fulup@iot.bzh + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + +*/ + +#define _GNU_SOURCE // needed for vasprintf + +#include "Alsa-ApiHat.h" + +// generic sndctrl event handle hook to event callback when pooling +typedef struct { + struct pollfd pfds; + sd_event_source *src; + snd_ctl_t *ctlDev; + int quiet; + struct afb_event afbevt; +} evtHandleT; + +typedef struct { + int ucount; + int cardId; + evtHandleT *evtHandle; +} sndHandleT; + +typedef struct { + char *apiprefix; + char *shortname; +}cardRegistryT; + +cardRegistryT *cardRegistry[MAX_SND_CARD+1]; + +// This routine is called when ALSA event are fired +STATIC int sndCtlEventCB (sd_event_source* src, int fd, uint32_t revents, void* userData) { + int err; + evtHandleT *evtHandle = (evtHandleT*)userData; + snd_ctl_event_t *eventId; + json_object *ctlEventJ; + unsigned int mask; + int iface; + int device; + int subdev; + const char*devname; + ctlRequestT ctlRequest; + snd_ctl_elem_id_t *elemId; + + if ((revents & EPOLLHUP) != 0) { + AFB_NOTICE( "SndCtl hanghup [car disconnected]"); + goto ExitOnSucess; + } + + if ((revents & EPOLLIN) != 0) { + + // initialise event structure on stack + snd_ctl_event_alloca(&eventId); + snd_ctl_elem_id_alloca(&elemId); + + err = snd_ctl_read(evtHandle->ctlDev, eventId); + if (err < 0) goto OnErrorExit; + + // we only process sndctrl element + if (snd_ctl_event_get_type(eventId) != SND_CTL_EVENT_ELEM) goto ExitOnSucess; + + // we only process value changed events + mask = snd_ctl_event_elem_get_mask(eventId); + if (!(mask & SND_CTL_EVENT_MASK_VALUE)) goto ExitOnSucess; + + snd_ctl_event_elem_get_id (eventId, elemId); + + err = alsaGetSingleCtl (evtHandle->ctlDev, elemId, &ctlRequest, evtHandle->quiet); + if (err) goto OnErrorExit; + + iface = snd_ctl_event_elem_get_interface(eventId); + device = snd_ctl_event_elem_get_device(eventId); + subdev = snd_ctl_event_elem_get_subdevice(eventId); + devname= snd_ctl_event_elem_get_name(eventId); + + // proxy ctlevent as a binder event + ctlEventJ = json_object_new_object(); + json_object_object_add(ctlEventJ, "device" ,json_object_new_int (device)); + json_object_object_add(ctlEventJ, "subdev" ,json_object_new_int (subdev)); + if (evtHandle->quiet < 2) { + json_object_object_add(ctlEventJ, "iface" ,json_object_new_int (iface)); + json_object_object_add(ctlEventJ, "devname",json_object_new_string (devname)); + } + if (ctlRequest.jValues) (json_object_object_add(ctlEventJ, "values" ,ctlRequest.jValues)); + AFB_DEBUG( "sndCtlEventCB=%s", json_object_get_string(ctlEventJ)); + afb_event_push(evtHandle->afbevt, ctlEventJ); + } + + ExitOnSucess: + return 0; + + OnErrorExit: + WARNING ("sndCtlEventCB: ignored unsupported event type"); + return (0); +} + +// Subscribe to every Alsa CtlEvent send by a given board +PUBLIC void alsaEvtSubcribe (afb_req request) { + static sndHandleT sndHandles[MAX_SND_CARD]; + evtHandleT *evtHandle; + snd_ctl_t *ctlDev; + int err, idx, cardId, idxFree=-1; + snd_ctl_card_info_t *cardinfo; + queryValuesT queryValues; + + + err = alsaCheckQuery (request, &queryValues); + if (err) goto OnErrorExit; + + + // open control interface for devid + err = snd_ctl_open(&ctlDev, queryValues.devid, SND_CTL_READONLY); + if (err < 0) { + ctlDev=NULL; + afb_req_fail_f (request, "devid-unknown", "SndCard devid=%s Not Found err=%s", queryValues.devid, snd_strerror(err)); + goto OnErrorExit; + } + + snd_ctl_card_info_alloca(&cardinfo); + if ((err = snd_ctl_card_info(ctlDev, cardinfo)) < 0) { + afb_req_fail_f (request, "devid-invalid", "SndCard devid=%s Not Found err=%s", queryValues.devid, snd_strerror(err)); + goto OnErrorExit; + } + + cardId=snd_ctl_card_info_get_card(cardinfo); + + // search for an existing subscription and mark 1st free slot + for (idx= 0; idx < MAX_SND_CARD; idx ++) { + if (sndHandles[idx].ucount > 0 && cardId == sndHandles[idx].cardId) { + evtHandle= sndHandles[idx].evtHandle; + break; + } else if (idxFree == -1) idxFree= idx; + }; + + // if not subscription exist for the event let's create one + if (idx == MAX_SND_CARD) { + + // reach MAX_SND_CARD event registration + if (idxFree == -1) { + afb_req_fail_f (request, "register-toomany", "Cannot register new event Maxcard==%d", idx); + goto OnErrorExit; + } + + evtHandle = malloc (sizeof(evtHandleT)); + evtHandle->ctlDev = ctlDev; + evtHandle->quiet = queryValues.quiet; + sndHandles[idxFree].ucount = 0; + sndHandles[idxFree].cardId = cardId; + sndHandles[idxFree].evtHandle = evtHandle; + + // subscribe for sndctl events attached to devid + err = snd_ctl_subscribe_events(evtHandle->ctlDev, 1); + if (err < 0) { + afb_req_fail_f (request, "subscribe-fail", "Cannot subscribe events from devid=%s err=%d", queryValues.devid, err); + goto OnErrorExit; + } + + // get pollfd attach to this sound board + snd_ctl_poll_descriptors(evtHandle->ctlDev, &evtHandle->pfds, 1); + + // register sound event to binder main loop + err = sd_event_add_io(afb_daemon_get_event_loop(), &evtHandle->src, evtHandle->pfds.fd, EPOLLIN, sndCtlEventCB, evtHandle); + if (err < 0) { + afb_req_fail_f (request, "register-mainloop", "Cannot hook events to mainloop devid=%s err=%d", queryValues.devid, err); + goto OnErrorExit; + } + + // create binder event attached to devid name + evtHandle->afbevt = afb_daemon_make_event (queryValues.devid); + if (!afb_event_is_valid (evtHandle->afbevt)) { + afb_req_fail_f (request, "register-event", "Cannot register new binder event name=%s", queryValues.devid); + goto OnErrorExit; + } + + // everything looks OK let's move forward + idx=idxFree; + } + + // subscribe to binder event + err = afb_req_subscribe(request, evtHandle->afbevt); + if (err != 0) { + afb_req_fail_f (request, "register-eventname", "Cannot subscribe binder event name=%s [invalid channel]", queryValues.devid); + goto OnErrorExit; + } + + // increase usage count and return success + sndHandles[idx].ucount ++; + afb_req_success(request, NULL, NULL); + return; + + OnErrorExit: + if (ctlDev) snd_ctl_close(ctlDev); + return; +} + +// Subscribe to every Alsa CtlEvent send by a given board +PUBLIC void alsaGetCardId (afb_req request) { + char devid [10]; + const char *devname, *shortname, *longname; + int card, err, index, idx; + json_object *respJson; + snd_ctl_t *ctlDev; + snd_ctl_card_info_t *cardinfo; + + const char *sndname = afb_req_value(request, "sndname"); + if (sndname == NULL) { + afb_req_fail_f (request, "argument-missing", "sndname=SndCardName missing"); + goto OnErrorExit; + } + + // loop on potential card number + snd_ctl_card_info_alloca(&cardinfo); + for (card =0; card < MAX_SND_CARD; card++) { + + // build card devid and probe it + snprintf (devid, sizeof(devid), "hw:%i", card); + + // open control interface for devid + err = snd_ctl_open(&ctlDev, devid, SND_CTL_READONLY); + if (err < 0) continue; + + // extract sound card information + snd_ctl_card_info(ctlDev, cardinfo); + index = snd_ctl_card_info_get_card(cardinfo); + devname = snd_ctl_card_info_get_id(cardinfo); + shortname= snd_ctl_card_info_get_name(cardinfo); + longname = snd_ctl_card_info_get_longname(cardinfo); + + // check if short|long name match + if (!strcmp (sndname, devname)) break; + if (!strcmp (sndname, shortname)) break; + if (!strcmp (sndname, longname)) break; + } + + if (card == MAX_SND_CARD) { + afb_req_fail_f (request, "ctlDev-notfound", "Fail to find card with name=%s", sndname); + goto OnErrorExit; + } + + // proxy ctlevent as a binder event + respJson = json_object_new_object(); + json_object_object_add(respJson, "index" ,json_object_new_int (index)); + json_object_object_add(respJson, "devid" ,json_object_new_string (devid)); + json_object_object_add(respJson, "shortname" ,json_object_new_string (shortname)); + json_object_object_add(respJson, "longname" ,json_object_new_string (longname)); + + // search for a HAL binder card mapping name to api prefix + for (idx=0; idx < MAX_SND_CARD; idx++) { + if (!strcmp (cardRegistry[idx]->shortname, shortname)) break; + } + // if a match if found, then we have an HAL for this board let's return its value + if (idx < MAX_SND_CARD) json_object_object_add(respJson, "halapi",json_object_new_string (cardRegistry[idx]->apiprefix)); + + afb_req_success(request, respJson, NULL); + return; + + OnErrorExit: + return; +} + +// Register loaded HAL with board Name and API prefix +PUBLIC void alsaRegisterHal (afb_req request) { + static int index=0; + const char *shortname, *apiPrefix; + + apiPrefix = afb_req_value(request, "prefix"); + if (apiPrefix == NULL) { + afb_req_fail_f (request, "argument-missing", "prefix=BindingApiPrefix missing"); + goto OnErrorExit; + } + + shortname = afb_req_value(request, "sndname"); + if (shortname == NULL) { + afb_req_fail_f (request, "argument-missing", "sndname=SndCardName missing"); + goto OnErrorExit; + } + + if (index == MAX_SND_CARD) { + afb_req_fail_f (request, "alsahal-toomany", "Fail to register sndname=[%s]", shortname); + goto OnErrorExit; + } + + cardRegistry[index]= malloc (sizeof(cardRegistry)); + cardRegistry[index]->apiprefix=strdup(apiPrefix); + cardRegistry[index]->shortname=strdup(shortname); + index++;cardRegistry[index]=NULL; + + // If OK return sound card Alsa ID+Info + alsaGetCardId(request); + return; + + OnErrorExit: + return; +} + -- cgit 1.2.3-korg