/*
* Copyright (C) 2016 "IoT.bzh"
* Author 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.
*
* Testing:
* 1) Copy generated plugin [libasound_module_pcm_afbhal.so] in alsa-lib/ dir visible from LD_LIBRARY_PATH (eg: /usr/lib64/alsa-lib)
* 2) Create a ~/.asounrc file base on following template
* ctl.agl_hal {
* type afbhal
* devid "hw:4"
* cblib "afbhal_cb_sample.so"
* ctls {
* # ctlLabel {numid integer name "Alsa Ctl Name"}
* MasterSwitch { numid 4 name "My_First_Control" }
* MasterVol { numid 5 name "My_Second_Control" }
* CB_sample { ctlcb @AfbHalSampleCB name "My_Sample_Callback"}
* }
* pcm.agl_hal {
* type copy # Copy PCM
* slave "hw:4" # Slave name
* }
*
* }
* 3) Test with
* - amixer -Dagl_hal controls # should list all your controls
* - amixer -Dagl_hal cget numid=1
* - amixer -Dagl_hal cset numid=1 '10,20'
*/
#include <stdio.h>
#include <sys/ioctl.h>
#include "HalPlug.h"
#include <dlfcn.h>
static snd_ctl_ext_key_t AfbHalElemFind(snd_ctl_ext_t *ext, const snd_ctl_elem_id_t *id) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
snd_ctl_ext_key_t key=NULL;
int numid = snd_ctl_elem_id_get_numid(id);
if (numid > 0) {
if (numid > plughandle->ctlsCount) goto OnErrorExit;
key= (snd_ctl_ext_key_t) numid -1;
goto SucessExit;
}
const char *ctlName= snd_ctl_elem_id_get_name(id);
if (ctlName == NULL) goto OnErrorExit;
for (int idx=0; idx < plughandle->ctlsCount; idx++) {
if (! strcmp(ctlName, plughandle->ctls[idx].ctlName)) {
key = idx;
goto SucessExit;
}
}
SucessExit:
return key;
OnErrorExit:
return -1;
}
static int AfbHalGetAttrib(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, int *type, unsigned int *acc, unsigned int *count) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
snd_ctl_elem_info_t *elemInfo = plughandle->infos[key];
snd_ctl_cb_t callback = plughandle->cbs[key];
// search for equivalent NUMID in effective sound card
if (elemInfo) {
*type = snd_ctl_elem_info_get_type(elemInfo);
*count = snd_ctl_elem_info_get_count(elemInfo);
*acc = SND_CTL_EXT_ACCESS_READWRITE; // Future ToBeDone
return 0;
}
if (callback) {
snd_ctl_get_attrib_t item;
int err = callback(plughandle, CTLCB_GET_ATTRIBUTE, key, &item);
if (!err) {
*type = item.type;
*acc = item.acc;
*count= item.count;
}
return err;
}
return -1;
}
static int AfbHalGetIntInfo(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, long *imin, long *imax, long *istep) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
snd_ctl_elem_info_t *elemInfo = plughandle->infos[key];
snd_ctl_cb_t callback = plughandle->cbs[key];
if (elemInfo) {
// Should be normalised to make everything 0-100%
*imin = (long)snd_ctl_elem_info_get_min(elemInfo);
*imax = (long)snd_ctl_elem_info_get_min(elemInfo);
*istep= (long)snd_ctl_elem_info_get_min(elemInfo);
return 0;
}
if (callback) {
snd_ctl_get_int_info_t item;
int err = callback(plughandle, CTLCB_GET_INTEGER_INFO, key, &item);
if (!err) {
*imin = item.imin;
*imax = item.imax;
*istep= item.istep;
}
return err;
}
return -1;
}
static int AfbHalGetEnumInfo(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int *items) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
snd_ctl_elem_info_t *elemInfo = plughandle->infos[key];
snd_ctl_cb_t callback = plughandle->cbs[key];
if(elemInfo) *items= snd_ctl_elem_info_get_items(elemInfo);
if(callback) callback(plughandle, CTLCB_GET_ENUMERATED_INFO, key, items);
return 0;
}
static int AfbHalGetEnumName(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int item, char *name, size_t name_max_len) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
snd_ctl_elem_info_t *elemInfo = plughandle->infos[key];
//name= snd_ctl_elem_info_get_item_name(elemInfo);
return 0;
}
static int AfbHalReadInt(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, long *value) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
snd_ctl_elem_info_t *elemInfo = plughandle->infos[key];
return 0;
}
static int AfbHalReadEnumerate(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int *items) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
return 0;
}
static int AfbHalWriteInt(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, long *value) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
return 0;
}
static int AfbHalWriteEnum(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int *items) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
return 0;
}
static int AfbHalEventRead(snd_ctl_ext_t *ext, snd_ctl_elem_id_t *id, unsigned int *event_mask) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
return -EAGAIN;
}
static int AfbHalElemList(snd_ctl_ext_t *ext, unsigned int offset, snd_ctl_elem_id_t *id) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_MIXER);
snd_ctl_elem_id_set_name(id, plughandle->ctls[offset].ctlName);
return 0;
}
static int AfbHalElemCount(snd_ctl_ext_t *ext) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
int count = plughandle->ctlsCount;
return count;
}
static void AfbHalClose(snd_ctl_ext_t *ext) {
snd_ctl_hal_t *plughandle = (snd_ctl_hal_t*) ext->private_data;
int err;
for (int idx=0; idx < plughandle->ctlsCount; idx++) {
if (plughandle->ctls[idx].ctlName) free((void*)plughandle->ctls[idx].ctlName);
}
err = snd_ctl_close(plughandle->ctlDev);
if (err) SNDERR("Fail Close sndctl: devid=%s err=%s", plughandle->devid, snd_strerror(err));
if (plughandle->devid) free(plughandle->devid);
free(plughandle);
}
static snd_ctl_ext_callback_t afbHalCBs = {
.close = AfbHalClose,
.elem_count = AfbHalElemCount,
.elem_list = AfbHalElemList,
.find_elem = AfbHalElemFind,
.get_attribute = AfbHalGetAttrib,
.get_integer_info = AfbHalGetIntInfo,
.get_enumerated_info = AfbHalGetEnumInfo,
.get_enumerated_name = AfbHalGetEnumName,
.read_integer = AfbHalReadInt,
.read_enumerated = AfbHalReadEnumerate,
.write_integer = AfbHalWriteInt,
.write_enumerated = AfbHalWriteEnum,
.read_event = AfbHalEventRead,
};
SND_CTL_PLUGIN_DEFINE_FUNC(afbhal) {
snd_config_iterator_t it, next;
snd_ctl_hal_t *plughandle;
int err;
snd_ctl_cb_t AfbHalInitCB;
const char *libname;
plughandle = calloc(1, sizeof(snd_ctl_hal_t));
snd_config_for_each(it, next, conf) {
snd_config_t *node = snd_config_iterator_entry(it);
const char *id;
// ignore comment en empty lines
if (snd_config_get_id(node, &id) < 0) continue;
if (strcmp(id, "comment") == 0 || strcmp(id, "type") == 0 || strcmp(id, "hint") == 0) continue;
// devid should point onto a valid sound card
if (strcmp(id, "devid") == 0) {
const char *devid;
if (snd_config_get_string(node, &devid) < 0) {
SNDERR("Invalid string type for %s", id);
return -EINVAL;
}
plughandle->devid=strdup(devid);
// open control interface for devid
err = snd_ctl_open(&plughandle->ctlDev, plughandle->devid, 0);
if (err < 0) {
SNDERR("Fail to open control device for devid=%s", plughandle->devid);
return -EINVAL;
}
continue;
}
if (strcmp(id, "cblib") == 0) {
if (snd_config_get_string(node, &libname) < 0) {
SNDERR("Invalid libname string for %s", id);
return -EINVAL;
}
plughandle->dlHandle= dlopen(libname, RTLD_NOW);
if (!plughandle->dlHandle) {
SNDERR("Fail to open callback sharelib=%s error=%s", libname, dlerror());
return -EINVAL;
}
AfbHalInitCB = dlsym(plughandle->dlHandle, "AfbHalInitCB");
if (!AfbHalInitCB) {
SNDERR("Fail find 'AfbHalInitCB' symbol into callbacks sharelib=%s", libname);
return -EINVAL;
}
err = (*AfbHalInitCB)(plughandle,CTLCB_INIT, 0,0);
if (err) {
SNDERR("Fail AfbHalInitCB err=%d", err);
return -EINVAL;
}
continue;
}
if (strcmp(id, "ctls") == 0) {
const char *ctlConf;
snd_config_type_t ctype;
snd_config_iterator_t currentCtl, follow;
snd_config_t *itemConf;
ctype = snd_config_get_type (node);
if (ctype != SND_CONFIG_TYPE_COMPOUND) {
snd_config_get_string (node, &ctlConf);
SNDERR("Invalid compound type for %s", node);
return -EINVAL;
}
// loop on each ctl within ctls
snd_config_for_each (currentCtl, follow, node) {
snd_config_t *ctlconfig = snd_config_iterator_entry(currentCtl);
snd_ctl_elem_info_t *elemInfo;
const char *ctlLabel, *ctlName;
// ignore empty line
if (snd_config_get_id(ctlconfig, &ctlLabel) < 0) continue;
// each clt should be a valid config compound
ctype = snd_config_get_type (ctlconfig);
if (ctype != SND_CONFIG_TYPE_COMPOUND) {
snd_config_get_string (node, &ctlConf);
SNDERR("Invalid ctl config for %s", ctlLabel);
return -EINVAL;
}
err=snd_config_search(ctlconfig, "numid", &itemConf);
if (!err) {
if (snd_config_get_integer(itemConf, (long*)&plughandle->ctls[plughandle->ctlsCount].ctlNumid) < 0) {
SNDERR("Not Integer: ctl:%s numid should be a valid integer", ctlLabel);
return -EINVAL;
}
// Make sure than numid is valid on slave snd card
snd_ctl_elem_info_malloc(&elemInfo);
snd_ctl_elem_info_set_numid(elemInfo, (int)plughandle->ctls[plughandle->ctlsCount].ctlNumid);
plughandle->infos[plughandle->ctlsCount]= elemInfo;
err = snd_ctl_elem_info(plughandle->ctlDev, elemInfo);
if (err) {
SNDERR("Not Found: 'numid=%d' for 'devid=%s'", plughandle->ctls[plughandle->ctlsCount].ctlNumid, plughandle->devid);
return -EINVAL;
}
}
err=snd_config_search(ctlconfig, "ctlcb", &itemConf);
if (!err) {
const char *funcname;
void *funcaddr;
if (snd_config_get_string(itemConf, &funcname) < 0) {
SNDERR("Not string: ctl:%s cbname should be a valid string", ctlLabel);
return -EINVAL;
}
if (funcname[0] != '@') {
SNDERR("Not string: ctl:%s cbname=%s should be prefixed with '@' ", ctlLabel, funcname);
return -EINVAL;
}
if (!plughandle->dlHandle) {
SNDERR("No CB: ctl:%s cblib:/my/libcallback missing from asoundrc", ctlLabel);
return -EINVAL;
}
funcaddr = dlsym(plughandle->dlHandle, &funcname[1]);
if (!funcaddr) {
SNDERR("NotFound CB: ctl:%s cbname='%s' no symbol into %s", ctlLabel, &funcname[1], libname);
return -EINVAL;
}
plughandle->cbs[plughandle->ctlsCount]=funcaddr;
}
err=snd_config_search(ctlconfig, "name", &itemConf);
if (err) {
SNDERR("Not Found: 'name' mandatory in ctl config");
return -EINVAL;
}
if (snd_config_get_string(itemConf, &ctlName) < 0) {
SNDERR("Not String: ctl:%s 'name' should be a valie string", ctlLabel);
return -EINVAL;
}
plughandle->ctls[plughandle->ctlsCount].ctlName = strdup(ctlName);
// move to next ctl if any
plughandle->ctlsCount++;
} // end for each ctl
continue;
}
SNDERR("Unknown field %s", id);
return -EINVAL;
}
// Create ALSA control plugin structure
plughandle->ext.version = SND_CTL_EXT_VERSION;
plughandle->ext.card_idx = 0; /* FIXME */
strcpy(plughandle->ext.id , "AFB-HAL-CTL");
strcpy(plughandle->ext.driver , "AFB-HAL");
strcpy(plughandle->ext.name , "AFB-HAL Control Plugin");
strcpy(plughandle->ext.mixername, "AFB-HAL Mixer Plugin");
strcpy(plughandle->ext.longname , "Automotive-Linux Sound Abstraction Control Plugin");
plughandle->ext.poll_fd = -1;
plughandle->ext.callback = &afbHalCBs;
plughandle->ext.private_data = (void*)plughandle;
err = snd_ctl_ext_create(&plughandle->ext, name, mode);
if (err < 0) {
SNDERR("Fail Register sndctl for devid=%s", plughandle->devid);
goto OnErrorExit;
}
// Plugin register controls update handlep before exiting
*handlep = plughandle->ext.handle;
return 0;
OnErrorExit:
free(plughandle);
return -1;
}
SND_CTL_PLUGIN_SYMBOL(afbhal);