[BlueZ,v1,1/3] shared/micp: Add initial code for handling micp and mics

- This commit is for implementations of MICS and MICP
- Specifications referred for implementation:
MICS - MICS_v1.0.pdf
MICP - MICP_v1.0.pdf
---
 Makefile.am           |   1 +
 Makefile.plugins      |   5 +
 configure.ac          |   4 +
 lib/uuid.h            |   4 +
 profiles/audio/micp.c | 340 ++++++++++++++++
 src/shared/micp.c     | 922 ++++++++++++++++++++++++++++++++++++++++++
 src/shared/micp.h     |  46 +++
 7 files changed, 1322 insertions(+)
 create mode 100644 profiles/audio/micp.c
 create mode 100644 src/shared/micp.c
 create mode 100644 src/shared/micp.h

Hi Mahesh,

On Thu, Aug 3, 2023 at 12:20 AM Mahesh Talewad <mahesh.talewad@nxp.com> wrote:
>
> - This commit is for implementations of MICS and MICP
> - Specifications referred for implementation:
> MICS - MICS_v1.0.pdf
> MICP - MICP_v1.0.pdf
> ---
>  Makefile.am           |   1 +
>  Makefile.plugins      |   5 +
>  configure.ac          |   4 +
>  lib/uuid.h            |   4 +
>  profiles/audio/micp.c | 340 ++++++++++++++++
>  src/shared/micp.c     | 922 ++++++++++++++++++++++++++++++++++++++++++
>  src/shared/micp.h     |  46 +++
>  7 files changed, 1322 insertions(+)
>  create mode 100644 profiles/audio/micp.c
>  create mode 100644 src/shared/micp.c
>  create mode 100644 src/shared/micp.h
>
> diff --git a/Makefile.am b/Makefile.am
> index 4b9b7e5cd..6f40f2a74 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -233,6 +233,7 @@ shared_sources = src/shared/io.h src/shared/timeout.h \
>                         src/shared/bap.h src/shared/bap.c src/shared/ascs.h \
>                         src/shared/mcs.h src/shared/mcp.h src/shared/mcp.c \
>                         src/shared/vcp.c src/shared/vcp.h \
> +                       src/shared/micp.c src/shared/micp.h \

Please split the changes adding micp.c and micp.h to shared to the
micp plugin, they are 2 very distinct instances so there is no reason
to keep them together.

>                         src/shared/csip.c src/shared/csip.h \
>                         src/shared/bass.h src/shared/bass.c \
>                         src/shared/lc3.h src/shared/tty.h
> diff --git a/Makefile.plugins b/Makefile.plugins
> index fc19522e4..5880ed0df 100644
> --- a/Makefile.plugins
> +++ b/Makefile.plugins
> @@ -137,6 +137,11 @@ builtin_modules += vcp
>  builtin_sources += profiles/audio/vcp.c
>  endif
>
> +if MICP
> +builtin_modules += micp
> +builtin_sources += profiles/audio/micp.c
> +endif
> +
>  if CSIP
>  builtin_modules += csip
>  builtin_sources += profiles/audio/csip.c
> diff --git a/configure.ac b/configure.ac
> index bc7edfcd3..9a8856380 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -211,6 +211,10 @@ AC_ARG_ENABLE(vcp, AS_HELP_STRING([--disable-vcp],
>                 [disable VCP profile]), [enable_vcp=${enableval}])
>  AM_CONDITIONAL(VCP, test "${enable_vcp}" != "no")
>
> +AC_ARG_ENABLE(micp, AS_HELP_STRING([--disable-micp],
> +               [disable MICP profile]), [enable_micp=${enableval}])
> +AM_CONDITIONAL(MICP, test "${enable_micp}" != "no")
> +
>  AC_ARG_ENABLE(csip, AS_HELP_STRING([--disable-csip],
>                 [disable CSIP profile]), [enable_csip=${enableval}])
>  AM_CONDITIONAL(CSIP, test "${enable_csip}" != "no")
> diff --git a/lib/uuid.h b/lib/uuid.h
> index cd3b3655f..6661a537f 100644
> --- a/lib/uuid.h
> +++ b/lib/uuid.h
> @@ -206,6 +206,10 @@ extern "C" {
>  #define CS_LOCK                                                0x2B86
>  #define CS_RANK                                                0x2B87
>
> +/* Microphone Control Service(MICS) */
> +#define MICS_UUID                      0x184D
> +#define MUTE_CHRC_UUID         0x2BC3
> +
>  typedef struct {
>         enum {
>                 BT_UUID_UNSPEC = 0,
> diff --git a/profiles/audio/micp.c b/profiles/audio/micp.c
> new file mode 100644
> index 000000000..452027c75
> --- /dev/null
> +++ b/profiles/audio/micp.c
> @@ -0,0 +1,340 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + *
> + *
> + *  BlueZ - Bluetooth protocol stack for Linux
> + *
> + *  Copyright (C) 2023  NXP Semiconductors. All rights reserved.
> + *
> + *
> + */
> +#ifdef HAVE_CONFIG_H
> +#include <config.h>
> +#endif
> +
> +#define        _GNU_SOURCE
> +
> +#include <ctype.h>
> +#include <stdbool.h>
> +#include <stdlib.h>
> +#include <stdio.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +#include <errno.h>
> +
> +#include <glib.h>
> +
> +#include "gdbus/gdbus.h"
> +
> +#include "lib/bluetooth.h"
> +#include "lib/hci.h"
> +#include "lib/sdp.h"
> +#include "lib/uuid.h"
> +
> +#include "src/dbus-common.h"
> +#include "src/shared/util.h"
> +#include "src/shared/att.h"
> +#include "src/shared/queue.h"
> +#include "src/shared/gatt-db.h"
> +#include "src/shared/gatt-server.h"
> +#include "src/shared/micp.h"
> +
> +#include "btio/btio.h"
> +#include "src/plugin.h"
> +#include "src/adapter.h"
> +#include "src/gatt-database.h"
> +#include "src/device.h"
> +#include "src/profile.h"
> +#include "src/service.h"
> +#include "src/log.h"
> +#include "src/error.h"
> +
> +#define MICS_UUID_STR  "0000184D-0000-1000-8000-00805f9b34fb"
> +
> +struct micp_data {
> +       struct btd_device *device;
> +       struct btd_service *service;
> +       struct bt_micp *micp;
> +       unsigned int ready_id;
> +};
> +
> +static struct queue *sessions;
> +
> +static void micp_debug(const char *str, void *user_data)
> +{
> +       DBG_IDX(0xffff, "%s", str);
> +}
> +
> +static int micp_disconnect(struct btd_service *service)
> +{
> +       return 0;
> +}
> +
> +static struct micp_data *micp_data_new(struct btd_device *device)
> +{
> +       struct micp_data *data;
> +
> +       data = new0(struct micp_data, 1);
> +       g_assert(data);
> +       data->device = device;
> +
> +       return data;
> +}
> +
> +static void micp_data_add(struct micp_data *data)
> +{
> +       DBG("data %p", data);
> +
> +       if (queue_find(sessions, NULL, data)) {
> +               error("data %p allready added", data);
> +               return;
> +       }
> +
> +       bt_micp_set_debug(data->micp, micp_debug, NULL, NULL);
> +
> +       if (!sessions)
> +               sessions = queue_new();
> +
> +       queue_push_tail(sessions, data);
> +
> +       if (data->service)
> +               btd_service_set_user_data(data->service, data);
> +}
> +
> +static bool match_data(const void *data, const void *match_data)
> +{
> +       const struct micp_data *mdata = data;
> +       const struct bt_micp *micp = match_data;
> +
> +       return mdata->micp == micp;
> +}
> +
> +static void micp_data_free(struct micp_data *data)
> +{
> +       if (data->service) {
> +               btd_service_set_user_data(data->service, NULL);
> +               bt_micp_set_user_data(data->micp, NULL);
> +       }
> +
> +       bt_micp_ready_unregister(data->micp, data->ready_id);
> +       bt_micp_unref(data->micp);
> +       free(data);
> +}
> +
> +static void micp_data_remove(struct micp_data *data)
> +{
> +       DBG("data %p", data);
> +
> +       if (!queue_remove(sessions, data))
> +               return;
> +
> +       micp_data_free(data);
> +
> +       if (queue_isempty(sessions)) {
> +               queue_destroy(sessions, NULL);
> +               sessions = NULL;
> +       }
> +}
> +
> +static void micp_detached(struct bt_micp *micp, void *user_data)
> +{
> +       struct micp_data *data;
> +
> +       DBG("%p", micp);
> +
> +       data = queue_find(sessions, match_data, micp);
> +       if (!data) {
> +               error("unable to find sessio");
> +               return;
> +       }
> +
> +       micp_data_remove(data);
> +}
> +
> +static void micp_ready(struct bt_micp *micp, void *user_data)
> +{
> +       DBG("micp %p\n", micp);
> +}
> +
> +static void micp_attached(struct bt_micp *micp, void *user_data)
> +{
> +       struct micp_data *data;
> +       struct bt_att *att;
> +       struct btd_device *device;
> +
> +       DBG("%p", micp);
> +
> +       data = queue_find(sessions, match_data, micp);
> +       if (data)
> +               return;
> +
> +       att = bt_micp_get_att(micp);
> +       if (!att)
> +               return;
> +
> +       device = btd_adapter_find_device_by_fd(bt_att_get_fd(att));
> +       if (!device) {
> +               error("unable to find device");
> +               return;
> +       }
> +
> +       data = micp_data_new(device);
> +       g_assert(data);
> +       data->micp = micp;
> +
> +       micp_data_add(data);
> +}
> +
> +static int micp_probe(struct btd_service *service)
> +{
> +       struct btd_device *device = btd_service_get_device(service);
> +       struct btd_adapter *adapter = device_get_adapter(device);
> +       struct btd_gatt_database *database = btd_adapter_get_database(adapter);
> +       struct micp_data *data = btd_service_get_user_data(service);
> +       char addr[18];
> +
> +       ba2str(device_get_address(device), addr);
> +       DBG("%s", addr);
> +
> +       /*Ignore, if we probed for this device allready */
> +       if (data) {
> +               error("Profile probed twice for this device");
> +               return -EINVAL;
> +       }
> +
> +       data = micp_data_new(device);
> +       data->service = service;
> +
> +       data->micp = bt_micp_new(btd_gatt_database_get_db(database),
> +                                       btd_device_get_gatt_db(device));
> +
> +       if (!data->micp) {
> +               error("unable to create MICP instance");
> +               free(data);
> +               return -EINVAL;
> +       }
> +
> +       micp_data_add(data);
> +
> +       data->ready_id = bt_micp_ready_register(data->micp, micp_ready, service,
> +                                                               NULL);
> +
> +       bt_micp_set_user_data(data->micp, service);
> +
> +       return 0;
> +}
> +
> +static void micp_remove(struct btd_service *service)
> +{
> +       struct btd_device *device = btd_service_get_device(service);
> +       struct micp_data *data;
> +       char addr[18];
> +
> +       ba2str(device_get_address(device), addr);
> +       DBG("%s", addr);
> +
> +       data = btd_service_get_user_data(service);
> +       if (!data) {
> +               error("MICP Service not handled by profile");
> +               return;
> +       }
> +
> +       micp_data_remove(data);
> +}
> +
> +static int micp_accept(struct btd_service *service)
> +{
> +       struct btd_device *device = btd_service_get_device(service);
> +       struct bt_gatt_client *client = btd_device_get_gatt_client(device);
> +       struct micp_data *data = btd_service_get_user_data(service);
> +       char addr[18];
> +
> +       ba2str(device_get_address(device), addr);
> +       DBG("%s", addr);
> +
> +       if (!data) {
> +               error("MICP Service not handled by profile");
> +               return -EINVAL;
> +       }
> +
> +       if (!bt_micp_attach(data->micp, client)) {
> +               error("MICP unable to attach");
> +               return -EINVAL;
> +       }
> +
> +       btd_service_connecting_complete(service, 0);
> +
> +       return 0;
> +}
> +
> +static int micp_connect(struct btd_service *service)
> +{
> +       struct btd_device *device = btd_service_get_device(service);
> +       char addr[18];
> +
> +       ba2str(device_get_address(device), addr);
> +       DBG("%s", addr);
> +
> +       return 0;
> +}
> +
> +static int micp_server_probe(struct btd_profile *p,
> +                               struct btd_adapter *adapter)
> +{
> +       struct btd_gatt_database *database = btd_adapter_get_database(adapter);
> +
> +       DBG("MICP path %s", adapter_get_path(adapter));
> +
> +       bt_micp_add_db(btd_gatt_database_get_db(database));
> +
> +       return 0;
> +}
> +
> +static void micp_server_remove(struct btd_profile *p,
> +                                       struct btd_adapter *adapter)
> +{
> +       DBG("MICP remove adapter");
> +}
> +
> +static struct btd_profile micp_profile = {
> +       .name           = "micp",
> +       .priority       = BTD_PROFILE_PRIORITY_MEDIUM,
> +       .remote_uuid    = MICS_UUID_STR,
> +
> +       .device_probe   = micp_probe,
> +       .device_remove  = micp_remove,
> +
> +       .accept = micp_accept,
> +       .connect        = micp_connect,
> +       .disconnect     = micp_disconnect,
> +
> +       .adapter_probe  = micp_server_probe,
> +       .adapter_remove = micp_server_remove,
> +};
> +
> +static unsigned int micp_id;
> +
> +static int micp_init(void)
> +{
> +       if (!(g_dbus_get_flags() & G_DBUS_FLAG_ENABLE_EXPERIMENTAL)) {
> +               warn("D-Bus experimental not enabled");
> +               return -ENOTSUP;
> +       }
> +
> +       btd_profile_register(&micp_profile);
> +       micp_id = bt_micp_register(micp_attached, micp_detached, NULL);
> +
> +       return 0;
> +}
> +
> +static void micp_exit(void)
> +{
> +       if (g_dbus_get_flags() & G_DBUS_FLAG_ENABLE_EXPERIMENTAL) {
> +               btd_profile_unregister(&micp_profile);
> +               bt_micp_unregister(micp_id);
> +       }
> +}
> +
> +BLUETOOTH_PLUGIN_DEFINE(micp, VERSION, BLUETOOTH_PLUGIN_PRIORITY_DEFAULT,
> +                                                       micp_init, micp_exit)
> diff --git a/src/shared/micp.c b/src/shared/micp.c
> new file mode 100644
> index 000000000..25ffa6940
> --- /dev/null
> +++ b/src/shared/micp.c
> @@ -0,0 +1,922 @@
> +// SPDX-License-Identifier: LGPL-2.1-or-later
> +/*
> + *
> + *  BlueZ - Bluetooth protocol stack for Linux
> + *
> + *  Copyright (C) 2023  NXP Semiconductors. All rights reserved.
> + *
> + */
> +#define _GNU_SOURCE
> +#include <inttypes.h>
> +#include <string.h>
> +#include <stdlib.h>
> +#include <stdbool.h>
> +#include <unistd.h>
> +#include <errno.h>
> +
> +#include "lib/bluetooth.h"
> +#include "lib/uuid.h"
> +
> +#include "src/shared/queue.h"
> +#include "src/shared/util.h"
> +#include "src/shared/timeout.h"
> +#include "src/shared/att.h"
> +#include "src/shared/gatt-db.h"
> +#include "src/shared/gatt-server.h"
> +#include "src/shared/gatt-helpers.h"
> +#include "src/shared/micp.h"
> +
> +#define DBG(_micp, fmt, arg...) \
> +       micp_debug(_micp, "%s:%s() " fmt, __FILE__, __func__, ##arg)
> +
> +/* Application error codes */
> +#define MICP_ERROR_MUTE_DISABLED            0x80
> +#define MICP_ERROR_VALUE_NOT_ALLOWED        0x13
> +#define BT_ATT_ERROR_OPCODE_NOT_SUPPORTED   0x81
> +
> +/* Mute char values */
> +#define MICS_NOT_MUTED  0x00
> +#define MICS_MUTED      0x01
> +#define MICS_DISABLED   0x02
> +
> +struct bt_micp_db {
> +       struct gatt_db *db;
> +       struct bt_mics *mics;
> +};
> +
> +struct bt_mics {
> +       struct bt_micp_db *mdb;
> +       uint8_t mute_stat;
> +       struct gatt_db_attribute *service;
> +       struct gatt_db_attribute *ms;
> +       struct gatt_db_attribute *ms_ccc;
> +};
> +
> +struct bt_micp {
> +       int ref_count;
> +       struct bt_micp_db *ldb;
> +       struct bt_micp_db *rdb;
> +       struct bt_gatt_client *client;
> +       struct bt_att *att;
> +       unsigned int mute_id;
> +
> +       unsigned int idle_id;
> +       uint8_t mute;
> +
> +       struct queue *notify;
> +       struct queue *pending;
> +       struct queue *ready_cbs;
> +
> +       bt_micp_debug_func_t debug_func;
> +       bt_micp_destroy_func_t debug_destroy;
> +
> +       void *debug_data;
> +       void *user_data;
> +};
> +
> +static struct queue *micp_db;
> +static struct queue *micp_cbs;
> +static struct queue *sessions;
> +
> +struct bt_micp_cb {
> +       unsigned int id;
> +       bt_micp_func_t attached;
> +       bt_micp_func_t detached;
> +       void *user_data;
> +};
> +
> +typedef void (*micp_func_t)(struct bt_micp *micp, bool success,
> +                               uint8_t att_ecode, const uint8_t *value,
> +                               uint16_t length, void *user_data);
> +
> +struct bt_micp_pending {
> +       unsigned int id;
> +       struct bt_micp *micp;
> +       micp_func_t func;
> +       void *userdata;
> +};
> +
> +struct bt_micp_ready {
> +       unsigned int id;
> +       bt_micp_ready_func_t func;
> +       bt_micp_destroy_func_t destroy;
> +       void *data;
> +};
> +
> +typedef void (*micp_notify_t)(struct bt_micp *micp, uint16_t value_handle,
> +                               const uint8_t *value, uint16_t length,
> +                               void *user_data);
> +
> +struct bt_micp_notify {
> +       unsigned int id;
> +       struct bt_micp *micp;
> +       micp_notify_t func;
> +       void *user_data;
> +};
> +
> +static void *iov_pull_mem(struct iovec *iov, size_t len)
> +{
> +       void *data = iov->iov_base;
> +
> +       if (iov->iov_len < len)
> +               return NULL;
> +
> +       iov->iov_base += len;
> +       iov->iov_len -= len;
> +
> +       return data;
> +}
> +
> +static struct bt_micp_db *micp_get_mdb(struct bt_micp *micp)
> +{
> +       if (!micp)
> +               return NULL;
> +
> +       if (micp->ldb)
> +               return micp->ldb;
> +
> +       return NULL;
> +}
> +
> +static uint8_t *mdb_get_mute_state(struct bt_micp_db *vdb)
> +{
> +       if (!vdb->mics)
> +               return NULL;
> +
> +       return &(vdb->mics->mute_stat);
> +}
> +
> +static struct bt_mics *micp_get_mics(struct bt_micp *micp)
> +{
> +       if (!micp)
> +               return NULL;
> +
> +       if (micp->rdb->mics)
> +               return micp->rdb->mics;
> +
> +       micp->rdb->mics = new0(struct bt_mics, 1);
> +       micp->rdb->mics->mdb = micp->rdb;
> +
> +       return micp->rdb->mics;
> +}
> +
> +static void micp_detached(void *data, void *user_data)
> +{
> +       struct bt_micp_cb *cb = data;
> +       struct bt_micp *micp = user_data;
> +
> +       cb->detached(micp, cb->user_data);
> +}
> +
> +void bt_micp_detach(struct bt_micp *micp)
> +{
> +       if (!queue_remove(sessions, micp))
> +               return;
> +
> +       bt_gatt_client_unref(micp->client);
> +       micp->client = NULL;
> +
> +       queue_foreach(micp_cbs, micp_detached, micp);
> +}
> +
> +static void micp_db_free(void *data)
> +{
> +       struct bt_micp_db *mdb = data;
> +
> +       if (!mdb)
> +               return;
> +
> +       gatt_db_unref(mdb->db);
> +
> +       free(mdb->mics);
> +       free(mdb);
> +}
> +
> +static void micp_ready_free(void *data)
> +{
> +       struct bt_micp_ready *ready = data;
> +
> +       if (ready->destroy)
> +               ready->destroy(ready->data);
> +
> +       free(ready);
> +}
> +
> +static void micp_free(void *data)
> +{
> +       struct bt_micp *micp = data;
> +
> +       bt_micp_detach(micp);
> +
> +       micp_db_free(micp->rdb);
> +
> +       queue_destroy(micp->pending, NULL);
> +       queue_destroy(micp->ready_cbs, micp_ready_free);
> +
> +       free(micp);
> +}
> +
> +bool bt_micp_set_user_data(struct bt_micp *micp, void *user_data)
> +{
> +
> +       if (!micp)
> +               return false;
> +
> +       micp->user_data = user_data;
> +
> +       return true;
> +}
> +
> +static bool micp_db_match(const void *data, const void *match_data)
> +{
> +       const struct bt_micp_db *mdb = data;
> +       const struct gatt_db *db = match_data;
> +
> +       return (mdb->db == db);
> +}
> +
> +struct bt_att *bt_micp_get_att(struct bt_micp *micp)
> +{
> +       if (!micp)
> +               return NULL;
> +
> +       if (micp->att)
> +               return micp->att;
> +
> +       return bt_gatt_client_get_att(micp->client);
> +}
> +
> +struct bt_micp *bt_micp_ref(struct bt_micp *micp)
> +{
> +       if (!micp)
> +               return NULL;
> +
> +       __sync_fetch_and_add(&micp->ref_count, 1);
> +
> +       return micp;
> +}
> +
> +void bt_micp_unref(struct bt_micp *micp)
> +{
> +       if (!micp)
> +               return;
> +
> +       if (__sync_sub_and_fetch(&micp->ref_count, 1))
> +               return;
> +
> +       micp_free(micp);
> +}
> +
> +static void micp_debug(struct bt_micp *micp, const char *format, ...)
> +{
> +       va_list ap;
> +
> +       if (!micp || !format || !micp->debug_func)
> +               return;
> +
> +       va_start(ap, format);
> +       util_debug_va(micp->debug_func, micp->debug_data, format, ap);
> +       va_end(ap);
> +}
> +
> +static void micp_disconnected(int err, void *user_data)
> +{
> +       struct bt_micp *micp = user_data;
> +
> +       DBG(micp, "micp %p disconnected err %d", micp, err);
> +
> +       bt_micp_detach(micp);
> +}
> +
> +static struct bt_micp *micp_get_session(struct bt_att *att, struct gatt_db *db)
> +{
> +       const struct queue_entry *entry;
> +       struct bt_micp *micp;
> +
> +       for (entry = queue_get_entries(sessions); entry; entry = entry->next) {
> +               struct bt_micp *micp = entry->data;
> +
> +               if (att == bt_micp_get_att(micp))
> +                       return micp;
> +       }
> +
> +       micp = bt_micp_new(db, NULL);
> +       micp->att = att;
> +
> +       bt_att_register_disconnect(att, micp_disconnected, micp, NULL);
> +
> +       bt_micp_attach(micp, NULL);
> +
> +       return micp;
> +}
> +
> +static void mics_mute_read(struct gatt_db_attribute *attrib,
> +                       unsigned int id, uint16_t offset,
> +                       uint8_t opcode, struct bt_att *att,
> +                       void *user_data)
> +{
> +       struct bt_mics *mics = user_data;
> +       struct iovec iov;
> +
> +       iov.iov_base = &mics->mute_stat;
> +       iov.iov_len = sizeof(mics->mute_stat);
> +
> +       gatt_db_attribute_read_result(attrib, id, 0, iov.iov_base,
> +                                                                 iov.iov_len);
> +}
> +
> +static uint8_t mics_not_muted(struct bt_mics *mics, struct bt_micp *micp,
> +                                                         struct iovec *iov)
> +{
> +       struct bt_micp_db *mdb;
> +       uint8_t *mute_state;
> +
> +       DBG(micp, "Mute state OP: Not Muted");
> +
> +       mdb = micp_get_mdb(micp);
> +       if (!mdb) {
> +               DBG(micp, "error: MDB not available");
> +               return 0;
> +       }
> +
> +       mute_state = mdb_get_mute_state(mdb);
> +       if (!mute_state) {
> +               DBG(micp, "Error : Mute State not available");
> +               return 0;
> +       }
> +
> +       *mute_state = MICS_NOT_MUTED;
> +
> +       gatt_db_attribute_notify(mdb->mics->ms, (void *)mute_state,
> +                               sizeof(uint8_t), bt_micp_get_att(micp));
> +
> +       return 0;
> +}
> +
> +static uint8_t mics_muted(struct bt_mics *mics, struct bt_micp *micp,
> +                                                 struct iovec *iov)
> +{
> +       struct bt_micp_db *mdb;
> +       uint8_t *mute_state;
> +
> +       DBG(micp, "Mute state OP: Muted");
> +
> +       mdb = micp_get_mdb(micp);
> +       if (!mdb) {
> +               DBG(micp, "error: MDB not available");
> +               return 0;
> +       }
> +
> +       mute_state = mdb_get_mute_state(mdb);
> +
> +       *mute_state = MICS_MUTED;
> +
> +       gatt_db_attribute_notify(mdb->mics->ms, (void *)mute_state,
> +                               sizeof(uint8_t), bt_micp_get_att(micp));
> +
> +       return 0;
> +}
> +
> +#define MICS_OP(_str, _op, _size, _func) \
> +       {                                    \
> +               .str = _str,                     \
> +               .op = _op,                       \
> +               .size = _size,                   \
> +               .func = _func,                   \
> +       }
> +
> +struct mics_op_handler {
> +       const char *str;
> +       uint8_t op;
> +       size_t size;
> +       uint8_t (*func)(struct bt_mics *mics, struct bt_micp *micp,
> +                                       struct iovec *iov);
> +} micp_handlers[] = {
> +       MICS_OP("Not Muted", MICS_NOT_MUTED,
> +                       sizeof(uint8_t), mics_not_muted),
> +       MICS_OP("Muted", MICS_MUTED,
> +                       sizeof(uint8_t), mics_muted),
> +       {}};
> +
> +static void mics_mute_write(struct gatt_db_attribute *attrib,
> +                                       unsigned int id, uint16_t offset,
> +                                       const uint8_t *value, size_t len,
> +                                       uint8_t opcode, struct bt_att *att,
> +                                       void *user_data)
> +{
> +       struct bt_mics *mics = user_data;
> +       struct bt_micp *micp = micp_get_session(att, mics->mdb->db);
> +       struct iovec iov = {
> +               .iov_base = (void *)value,
> +               .iov_len = len,
> +       };
> +       uint8_t *micp_op, *mute_state;
> +       struct mics_op_handler *handler;
> +       uint8_t ret = BT_ATT_ERROR_REQUEST_NOT_SUPPORTED;
> +       struct bt_micp_db *mdb;
> +
> +       DBG(micp, "MICS Mute Char write: len: %ld: %ld", len, iov.iov_len);
> +
> +       if (offset) {
> +               DBG(micp, "invalid offset: %d", offset);
> +               ret = BT_ATT_ERROR_INVALID_OFFSET;
> +               goto respond;
> +       }
> +
> +       if (len < sizeof(*micp_op)) {
> +               DBG(micp, "invalid length: %ld < %ld sizeof(param)", len,
> +                       sizeof(*micp_op));
> +               ret = BT_ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LEN;
> +               goto respond;
> +       }
> +
> +       micp_op = iov_pull_mem(&iov, sizeof(*micp_op));
> +
> +       if ((*micp_op == MICS_DISABLED) || (*micp_op != MICS_NOT_MUTED
> +               && *micp_op != MICS_MUTED)) {
> +               DBG(micp, "Invalid operation - MICS DISABLED/RFU mics op:%d",
> +                                       micp_op);
> +               ret = MICP_ERROR_VALUE_NOT_ALLOWED;
> +               goto respond;
> +       }
> +
> +       mdb = micp_get_mdb(micp);
> +       if (!mdb) {
> +               DBG(micp, "error: MDB not available");
> +               goto respond;
> +       }
> +
> +       mute_state = mdb_get_mute_state(mdb);
> +       if (*mute_state == MICS_DISABLED) {
> +               DBG(micp, "state: MICS DISABLED , can not write value: %d",
> +                               *micp_op);
> +               ret = MICP_ERROR_MUTE_DISABLED;
> +               goto respond;
> +       }
> +
> +       for (handler = micp_handlers; handler && handler->str; handler++) {
> +               DBG(micp, "handler->op: %d micp_op: %d iov.iov_len: %ld",
> +                                       handler->op, *micp_op, iov.iov_len);
> +               if (handler->op != *micp_op)
> +                       continue;
> +
> +               if (len < handler->size) {
> +                       DBG(micp, "invalid len %ld : %ld < %ld handler->size",
> +                       len, iov.iov_len, handler->size);
> +                       ret = BT_ATT_ERROR_OPCODE_NOT_SUPPORTED;
> +                       goto respond;
> +               }
> +
> +               break;
> +       }
> +
> +       if (handler && handler->str) {
> +               DBG(micp, "%s", handler->str);
> +
> +               ret = handler->func(mics, micp, &iov);
> +       } else {
> +               DBG(micp, "unknown opcode 0x%02x", *micp_op);
> +               ret = BT_ATT_ERROR_OPCODE_NOT_SUPPORTED;
> +       }
> +
> +respond:
> +       gatt_db_attribute_write_result(attrib, id, ret);
> +}
> +
> +static struct bt_mics *mics_new(struct gatt_db *db)
> +{
> +       struct bt_mics *mics;
> +       bt_uuid_t uuid;
> +
> +       if (!db)
> +               return NULL;
> +
> +       mics = new0(struct bt_mics, 1);
> +
> +       mics->mute_stat = MICS_MUTED;
> +
> +       /* Populate DB with MICS attributes */
> +       bt_uuid16_create(&uuid, MICS_UUID);
> +       mics->service = gatt_db_add_service(db, &uuid, true, 4);
> +
> +       bt_uuid16_create(&uuid, MUTE_CHRC_UUID);
> +       mics->ms = gatt_db_service_add_characteristic(mics->service,
> +                               &uuid,
> +                               BT_ATT_PERM_READ | BT_ATT_PERM_WRITE,
> +                               BT_GATT_CHRC_PROP_READ | BT_GATT_CHRC_PROP_WRITE
> +                               | BT_GATT_CHRC_PROP_NOTIFY,
> +                               mics_mute_read, mics_mute_write,
> +                               mics);
> +
> +       mics->ms_ccc = gatt_db_service_add_ccc(mics->service,
> +                               BT_ATT_PERM_READ | BT_ATT_PERM_WRITE);
> +
> +       gatt_db_service_set_active(mics->service, true);
> +
> +       return mics;
> +}
> +
> +static struct bt_micp_db *micp_db_new(struct gatt_db *db)
> +{
> +       struct bt_micp_db *mdb;
> +
> +       if (!db)
> +               return NULL;
> +
> +       mdb = new0(struct bt_micp_db, 1);
> +       mdb->db = gatt_db_ref(db);
> +
> +       if (!micp_db)
> +               micp_db = queue_new();
> +
> +       mdb->mics = mics_new(db);
> +       mdb->mics->mdb = mdb;
> +
> +       queue_push_tail(micp_db, mdb);
> +
> +       return mdb;
> +}
> +
> +static struct bt_micp_db *micp_get_db(struct gatt_db *db)
> +{
> +       struct bt_micp_db *mdb;
> +
> +       mdb = queue_find(micp_db, micp_db_match, db);
> +       if (mdb)
> +               return mdb;
> +
> +       return micp_db_new(db);
> +}
> +
> +void bt_micp_add_db(struct gatt_db *db)
> +{
> +       micp_db_new(db);
> +}
> +
> +bool bt_micp_set_debug(struct bt_micp *micp, bt_micp_debug_func_t func,
> +                       void *user_data, bt_micp_destroy_func_t destroy)
> +{
> +       if (!micp)
> +               return false;
> +
> +       if (micp->debug_destroy)
> +               micp->debug_destroy(micp->debug_data);
> +
> +       micp->debug_func = func;
> +       micp->debug_destroy = destroy;
> +       micp->debug_data = user_data;
> +
> +       return true;
> +}
> +
> +unsigned int bt_micp_register(bt_micp_func_t attached, bt_micp_func_t detached,
> +                                                         void *user_data)
> +{
> +       struct bt_micp_cb *cb;
> +       static unsigned int id;
> +
> +       if (!attached && !detached)
> +               return 0;
> +
> +       if (!micp_cbs)
> +               micp_cbs = queue_new();
> +
> +       cb = new0(struct bt_micp_cb, 1);
> +       cb->id = ++id ? id : ++id;
> +       cb->attached = attached;
> +       cb->detached = detached;
> +       cb->user_data = user_data;
> +
> +       queue_push_tail(micp_cbs, cb);
> +
> +       return cb->id;
> +}
> +
> +static bool match_id(const void *data, const void *match_data)
> +{
> +       const struct bt_micp_cb *cb = data;
> +       unsigned int id = PTR_TO_UINT(match_data);
> +
> +       return (cb->id == id);
> +}
> +
> +bool bt_micp_unregister(unsigned int id)
> +{
> +       struct bt_micp_cb *cb;
> +
> +       cb = queue_remove_if(micp_cbs, match_id, UINT_TO_PTR(id));
> +       if (!cb)
> +               return false;
> +
> +       free(cb);
> +
> +       return true;
> +}
> +
> +struct bt_micp *bt_micp_new(struct gatt_db *ldb, struct gatt_db *rdb)
> +{
> +       struct bt_micp *micp;
> +       struct bt_micp_db *mdb;
> +
> +       if (!ldb)
> +               return NULL;
> +
> +       mdb = micp_get_db(ldb);
> +       if (!mdb)
> +               return NULL;
> +
> +       micp = new0(struct bt_micp, 1);
> +       micp->ldb = mdb;
> +       micp->pending = queue_new();
> +       micp->ready_cbs = queue_new();
> +
> +       if (!rdb)
> +               goto done;
> +
> +       mdb = new0(struct bt_micp_db, 1);
> +       mdb->db = gatt_db_ref(rdb);
> +
> +       micp->rdb = mdb;
> +
> +done:
> +       bt_micp_ref(micp);
> +
> +       return micp;
> +}
> +
> +static void micp_pending_destroy(void *data)
> +{
> +       struct bt_micp_pending *pending = data;
> +       struct bt_micp *micp = pending->micp;
> +
> +       if (queue_remove_if(micp->pending, NULL, pending))
> +               free(pending);
> +}
> +
> +static void micp_pending_complete(bool success, uint8_t att_ecode,
> +                               const uint8_t *value, uint16_t length,
> +                               void *user_data)
> +{
> +       struct bt_micp_pending *pending = user_data;
> +
> +       if (pending->func)
> +               pending->func(pending->micp, success, att_ecode, value, length,
> +                                         pending->userdata);
> +}
> +
> +static void micp_read_value(struct bt_micp *micp, uint16_t value_handle,
> +                               micp_func_t func, void *user_data)
> +{
> +       struct bt_micp_pending *pending;
> +
> +       pending = new0(struct bt_micp_pending, 1);
> +       pending->micp = micp;
> +       pending->func = func;
> +       pending->userdata = user_data;
> +
> +       pending->id = bt_gatt_client_read_value(micp->client, value_handle,
> +                                       micp_pending_complete, pending,
> +                                       micp_pending_destroy);
> +
> +       if (!pending->id) {
> +               DBG(micp, "unable to send read request");
> +               free(pending);
> +               return;
> +       }
> +
> +       queue_push_tail(micp->pending, pending);
> +}
> +
> +static void micp_register(uint16_t att_ecode, void *user_data)
> +{
> +       struct bt_micp_notify *notify = user_data;
> +
> +       if (att_ecode)
> +               DBG(notify->micp, "MICP register failed 0x%04x", att_ecode);
> +}
> +
> +static void micp_notify(uint16_t value_handle, const uint8_t *value,
> +                               uint16_t length, void *user_data)
> +{
> +       struct bt_micp_notify *notify = user_data;
> +
> +       if (notify->func)
> +               notify->func(notify->micp, value_handle, value, length,
> +                                        notify->user_data);
> +}
> +
> +static void micp_notify_destroy(void *data)
> +{
> +       struct bt_micp_notify *notify = data;
> +       struct bt_micp *micp = notify->micp;
> +
> +       if (queue_remove_if(micp->notify, NULL, notify))
> +               free(notify);
> +}
> +
> +static unsigned int micp_register_notify(struct bt_micp *micp,
> +                                       uint16_t value_handle,
> +                                       micp_notify_t func,
> +                                       void *user_data)
> +{
> +       struct bt_micp_notify *notify;
> +
> +       notify = new0(struct bt_micp_notify, 1);
> +       notify->micp = micp;
> +       notify->func = func;
> +       notify->user_data = user_data;
> +
> +       notify->id = bt_gatt_client_register_notify(micp->client,
> +                                       value_handle, micp_register,
> +                                       micp_notify, notify,
> +                                       micp_notify_destroy);
> +       if (!notify->id) {
> +               DBG(micp, "Unable to register for notifications");
> +               free(notify);
> +               return 0;
> +       }
> +
> +       queue_push_tail(micp->notify, notify);
> +
> +       return notify->id;
> +}
> +
> +static void micp_mute_state_notify(struct bt_micp *micp, uint16_t value_handle,
> +                                       const uint8_t *value, uint16_t length,
> +                                       void *user_data)
> +{
> +       uint8_t mute_state;
> +
> +       memcpy(&mute_state, value, sizeof(mute_state));
> +
> +       DBG(micp, "Mute state: 0x%x", mute_state);
> +}
> +
> +static void read_mute_state(struct bt_micp *micp, bool success,
> +                                       uint8_t att_ecode, const uint8_t *value,
> +                                       uint16_t length, void *user_data)
> +{
> +       uint8_t *mute_state;
> +       struct iovec iov = {
> +               .iov_base = (void *)value,
> +               .iov_len = length,
> +       };
> +
> +       if (!success) {
> +               DBG(micp, "Unable to read Mute state: error 0x%02x", att_ecode);
> +               return;
> +       }
> +
> +       mute_state = iov_pull_mem(&iov, sizeof(uint8_t));
> +       if (mute_state == NULL) {
> +               DBG(micp, "Unable to get Mute state");
> +               return;
> +       }
> +
> +       DBG(micp, "Mute state: %x", *mute_state);
> +}
> +
> +static void foreach_mics_char(struct gatt_db_attribute *attr, void *user_data)
> +{
> +       struct bt_micp *micp = user_data;
> +       uint16_t value_handle;
> +       bt_uuid_t uuid, uuid_mute;
> +       struct bt_mics *mics;
> +
> +       if (!gatt_db_attribute_get_char_data(attr, NULL, &value_handle,
> +                       NULL, NULL, &uuid))
> +               return;
> +
> +       bt_uuid16_create(&uuid_mute, MUTE_CHRC_UUID);
> +       if (!bt_uuid_cmp(&uuid, &uuid_mute)) {
> +               DBG(micp, "MICS Mute characteristic found: handle 0x%04x",
> +                               value_handle);
> +
> +               mics = micp_get_mics(micp);
> +               if (!mics || mics->ms)
> +                       return;
> +
> +               mics->ms = attr;
> +
> +               micp_read_value(micp, value_handle, read_mute_state, micp);
> +
> +               micp->mute_id = micp_register_notify(micp, value_handle,
> +                                               micp_mute_state_notify, NULL);
> +       }
> +}
> +
> +static void foreach_mics_service(struct gatt_db_attribute *attr,
> +                                       void *user_data)
> +{
> +       struct bt_micp *micp = user_data;
> +       struct bt_mics *mics = micp_get_mics(micp);
> +
> +       mics->service = attr;
> +
> +       gatt_db_service_set_claimed(attr, true);
> +       gatt_db_service_foreach_char(attr, foreach_mics_char, micp);
> +}
> +
> +unsigned int bt_micp_ready_register(struct bt_micp *micp,
> +                               bt_micp_ready_func_t func, void *user_data,
> +                               bt_micp_destroy_func_t destroy)
> +{
> +       struct bt_micp_ready *ready;
> +       static unsigned int id;
> +
> +       DBG(micp, "bt_micp_ready_register_Entry\n");
> +       if (!micp)
> +               return 0;
> +
> +       ready = new0(struct bt_micp_ready, 1);
> +       ready->id = ++id ? id : ++id;
> +       ready->func = func;
> +       ready->destroy = destroy;
> +       ready->data = user_data;
> +
> +       queue_push_tail(micp->ready_cbs, ready);
> +
> +       return ready->id;
> +}
> +
> +static bool match_ready_id(const void *data, const void *match_data)
> +{
> +       const struct bt_micp_ready *ready = data;
> +       unsigned int id = PTR_TO_UINT(match_data);
> +
> +       return (ready->id == id);
> +}
> +
> +bool bt_micp_ready_unregister(struct bt_micp *micp, unsigned int id)
> +{
> +       struct bt_micp_ready *ready;
> +
> +       ready = queue_remove_if(micp->ready_cbs, match_ready_id,
> +                                               UINT_TO_PTR(id));
> +       if (!ready)
> +               return false;
> +
> +       micp_ready_free(ready);
> +
> +       return true;
> +}
> +
> +static struct bt_micp *bt_micp_ref_safe(struct bt_micp *micp)
> +{
> +       if (!micp || !micp->ref_count)
> +               return NULL;
> +
> +       return bt_micp_ref(micp);
> +}
> +
> +static void micp_notify_ready(struct bt_micp *micp)
> +{
> +       const struct queue_entry *entry;
> +
> +       if (!bt_micp_ref_safe(micp))
> +               return;
> +
> +       for (entry = queue_get_entries(micp->ready_cbs); entry;
> +                                                       entry = entry->next) {
> +               struct bt_micp_ready *ready = entry->data;
> +
> +               ready->func(micp, ready->data);
> +       }
> +
> +       bt_micp_unref(micp);
> +}
> +
> +static void micp_idle(void *data)
> +{
> +       struct bt_micp *micp = data;
> +
> +       micp->idle_id = 0;
> +       micp_notify_ready(micp);
> +}
> +
> +bool bt_micp_attach(struct bt_micp *micp, struct bt_gatt_client *client)
> +{
> +       bt_uuid_t uuid;
> +
> +       if (!sessions)
> +               sessions = queue_new();
> +
> +       queue_push_tail(sessions, micp);
> +
> +       if (!client)
> +               return true;
> +
> +       if (micp->client)
> +               return false;
> +
> +       micp->client = bt_gatt_client_clone(client);
> +       if (!micp->client)
> +               return false;
> +
> +       bt_gatt_client_idle_register(micp->client, micp_idle, micp, NULL);
> +
> +       bt_uuid16_create(&uuid, MICS_UUID);
> +       gatt_db_foreach_service(micp->ldb->db, &uuid, foreach_mics_service,
> +                                               micp);
> +       return true;
> +}
> diff --git a/src/shared/micp.h b/src/shared/micp.h
> new file mode 100644
> index 000000000..b307ac9f4
> --- /dev/null
> +++ b/src/shared/micp.h
> @@ -0,0 +1,46 @@
> +/* SPDX-License-Identifier: LGPL-2.1-or-later */
> +/*
> + *
> + *  BlueZ - Bluetooth protocol stack for Linux
> + *
> + *  Copyright (C) 2023  NXP Semiconductors. All rights reserved.
> + *
> + */
> +#include <stdbool.h>
> +#include <inttypes.h>
> +
> +#include "src/shared/io.h"
> +#include "src/shared/gatt-client.h"
> +
> +struct bt_micp;
> +
> +typedef void (*bt_micp_ready_func_t)(struct bt_micp *micp, void *user_data);
> +typedef void (*bt_micp_destroy_func_t)(void *user_data);
> +typedef void (*bt_micp_debug_func_t)(const char *str, void *user_data);
> +typedef void (*bt_micp_func_t)(struct bt_micp *micp, void *user_data);
> +
> +struct bt_micp *bt_micp_ref(struct bt_micp *micp);
> +void bt_micp_unref(struct bt_micp *micp);
> +
> +void bt_micp_add_db(struct gatt_db *db);
> +
> +bool bt_micp_attach(struct bt_micp *micp, struct bt_gatt_client *client);
> +void bt_micp_detach(struct bt_micp *micp);
> +
> +bool bt_micp_set_debug(struct bt_micp *micp, bt_micp_debug_func_t func,
> +               void *user_data, bt_micp_destroy_func_t destroy);
> +
> +struct bt_att *bt_micp_get_att(struct bt_micp *micp);
> +
> +bool bt_micp_set_user_data(struct bt_micp *micp, void *user_data);
> +
> +/* session related functions */
> +unsigned int bt_micp_register(bt_micp_func_t attached, bt_micp_func_t detached,
> +                                       void *user_data);
> +unsigned int bt_micp_ready_register(struct bt_micp *micp,
> +                               bt_micp_ready_func_t func, void *user_data,
> +                               bt_micp_destroy_func_t destroy);
> +bool bt_micp_ready_unregister(struct bt_micp *micp, unsigned int id);
> +
> +bool bt_micp_unregister(unsigned int id);
> +struct bt_micp *bt_micp_new(struct gatt_db *ldb, struct gatt_db *rdb);
> --
> 2.34.1
>