[PATCH BlueZ v2 3/5] audio/hfp-hf: Add skeleton for HFP profile

["Frédéric Danis" <frederic.danis@collabora.com>]

This starts the Telephony interface for HFP HF, allowing to connect to
the remote HFP AG device.
---
v1->v2:
- Fix 'make distcheck' by adding missing profiles/audio/telephony.h to
  builtin_sources
- Improve commit message

 Makefile.plugins        |   5 +
 configure.ac            |   7 ++
 profiles/audio/hfp-hf.c | 220 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 232 insertions(+)
 create mode 100644 profiles/audio/hfp-hf.c

diff --git a/Makefile.plugins b/Makefile.plugins
index 3572ee845..3a95b5fb5 100644
--- a/Makefile.plugins
+++ b/Makefile.plugins
@@ -160,3 +160,8 @@ if ASHA
 builtin_modules += asha
 builtin_sources += profiles/audio/asha.h profiles/audio/asha.c
 endif
+
+if HFP
+builtin_modules += hfp
+builtin_sources += profiles/audio/telephony.h profiles/audio/telephony.c profiles/audio/hfp-hf.c
+endif
diff --git a/configure.ac b/configure.ac
index 16b81aca3..b6f6789be 100644
--- a/configure.ac
+++ b/configure.ac
@@ -248,6 +248,13 @@ if test "${enable_asha}" != "no"; then
 	AC_DEFINE(HAVE_ASHA, 1, [Define to 1 if you have ASHA support.])
 fi
 
+AC_ARG_ENABLE(hfp, AS_HELP_STRING([--disable-hfp],
+		[disable HFP support]), [enable_hfp=${enableval}])
+AM_CONDITIONAL(HFP, test "${enable_hfp}" != "no")
+if test "${enable_hfp}" != "no"; then
+	AC_DEFINE(HAVE_HFP, 1, [Define to 1 if you have HFP support.])
+fi
+
 AC_ARG_ENABLE(tools, AS_HELP_STRING([--disable-tools],
 		[disable Bluetooth tools]), [enable_tools=${enableval}])
 AM_CONDITIONAL(TOOLS, test "${enable_tools}" != "no")
diff --git a/profiles/audio/hfp-hf.c b/profiles/audio/hfp-hf.c
new file mode 100644
index 000000000..5375168cf
--- /dev/null
+++ b/profiles/audio/hfp-hf.c
@@ -0,0 +1,220 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *
+ *  BlueZ - Bluetooth protocol stack for Linux
+ *
+ *  Copyright (C) 2014  Intel Corporation. All rights reserved.
+ *  Copyright © 2025 Collabora Ltd.
+ *
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <limits.h>
+
+#include <stdint.h>
+
+#include <glib.h>
+
+#include "bluetooth/bluetooth.h"
+#include "bluetooth/sdp.h"
+#include "bluetooth/sdp_lib.h"
+#include "bluetooth/uuid.h"
+
+#include "gdbus/gdbus.h"
+
+#include "btio/btio.h"
+#include "src/adapter.h"
+#include "src/btd.h"
+#include "src/dbus-common.h"
+#include "src/device.h"
+#include "src/log.h"
+#include "src/plugin.h"
+#include "src/profile.h"
+#include "src/service.h"
+
+#include "telephony.h"
+
+#define URI	"tel"
+#define URI_PREFIX	URI ":"
+
+struct hfp_device {
+	struct telephony	*telephony;
+	uint16_t		version;
+	GIOChannel		*io;
+};
+
+static void device_destroy(struct hfp_device *dev)
+{
+	DBG("%s", telephony_get_path(dev->telephony));
+
+	if (dev->io) {
+		g_io_channel_unref(dev->io);
+		dev->io = NULL;
+	}
+
+	telephony_unregister_interface(dev->telephony);
+}
+
+static void connect_cb(GIOChannel *chan, GError *err, gpointer user_data)
+{
+	struct hfp_device *dev = user_data;
+	struct btd_service *service = telephony_get_service(dev->telephony);
+
+	DBG("");
+
+	if (err) {
+		error("%s", err->message);
+		goto failed;
+	}
+
+	g_io_channel_set_close_on_unref(chan, FALSE);
+
+	btd_service_connecting_complete(service, 0);
+
+	return;
+
+failed:
+	g_io_channel_shutdown(chan, TRUE, NULL);
+	device_destroy(dev);
+}
+
+struct telephony_callbacks hfp_callbacks = {
+};
+
+static int hfp_connect(struct btd_service *service)
+{
+	struct hfp_device *dev;
+	struct btd_profile *p;
+	const sdp_record_t *rec;
+	sdp_list_t *list, *protos;
+	sdp_profile_desc_t *desc;
+	int channel;
+	bdaddr_t src, dst;
+	GError *err = NULL;
+
+	DBG("");
+
+	dev = btd_service_get_user_data(service);
+
+	p = btd_service_get_profile(service);
+	rec = btd_device_get_record(telephony_get_device(dev->telephony),
+					p->remote_uuid);
+	if (!rec)
+		return -EIO;
+
+	if (sdp_get_profile_descs(rec, &list) == 0) {
+		desc = list->data;
+		dev->version = desc->version;
+	}
+	sdp_list_free(list, free);
+
+	if (sdp_get_access_protos(rec, &protos) < 0) {
+		error("unable to get access protocols from record");
+		return -EIO;
+	}
+
+	channel = sdp_get_proto_port(protos, RFCOMM_UUID);
+	sdp_list_foreach(protos, (sdp_list_func_t) sdp_list_free, NULL);
+	sdp_list_free(protos, NULL);
+	if (channel <= 0) {
+		error("unable to get RFCOMM channel from record");
+		return -EIO;
+	}
+
+	src = telephony_get_src(dev->telephony);
+	dst = telephony_get_dst(dev->telephony);
+	dev->io = bt_io_connect(connect_cb, dev,
+		NULL, &err,
+		BT_IO_OPT_SOURCE_BDADDR, &src,
+		BT_IO_OPT_DEST_BDADDR, &dst,
+		BT_IO_OPT_SEC_LEVEL, BT_IO_SEC_MEDIUM,
+		BT_IO_OPT_CHANNEL, channel,
+		BT_IO_OPT_INVALID);
+	if (dev->io == NULL) {
+		error("unable to start connection");
+		return -EIO;
+	}
+
+	return telephony_register_interface(dev->telephony);
+}
+
+static int hfp_disconnect(struct btd_service *service)
+{
+	DBG("");
+
+	btd_service_disconnecting_complete(service, 0);
+
+	return 0;
+}
+
+static int hfp_probe(struct btd_service *service)
+{
+	struct btd_device *device = btd_service_get_device(service);
+	const char *path = device_get_path(device);
+	struct hfp_device *dev;
+
+	DBG("%s", path);
+
+	dev = g_new0(struct hfp_device, 1);
+	if (!dev)
+		return -EINVAL;
+
+	dev->telephony = telephony_new(service, dev, &hfp_callbacks);
+	btd_service_set_user_data(service, dev);
+	telephony_add_uri_scheme(dev->telephony, URI);
+
+	return 0;
+}
+
+static void hfp_remove(struct btd_service *service)
+{
+	struct btd_device *device = btd_service_get_device(service);
+	const char *path = device_get_path(device);
+	struct hfp_device *dev;
+
+	DBG("%s", path);
+
+	dev = btd_service_get_user_data(service);
+
+	telephony_free(dev->telephony);
+	g_free(dev);
+}
+
+static struct btd_profile hfp_hf_profile = {
+	.name		= "hfp",
+	.priority	= BTD_PROFILE_PRIORITY_MEDIUM,
+
+	.remote_uuid	= HFP_AG_UUID,
+	.device_probe	= hfp_probe,
+	.device_remove	= hfp_remove,
+
+	.auto_connect	= true,
+	.connect	= hfp_connect,
+	.disconnect	= hfp_disconnect,
+
+	.experimental	= true,
+};
+
+static int hfp_init(void)
+{
+	btd_profile_register(&hfp_hf_profile);
+
+	return 0;
+}
+
+static void hfp_exit(void)
+{
+	btd_profile_unregister(&hfp_hf_profile);
+}
+
+BLUETOOTH_PLUGIN_DEFINE(hfp, VERSION, BLUETOOTH_PLUGIN_PRIORITY_DEFAULT,
+		hfp_init, hfp_exit)
-- 
2.43.0