From 16f31547548338d40e51cce73471847b60c13d52 Mon Sep 17 00:00:00 2001
From: Andrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Date: Tue, 25 Sep 2012 16:27:41 +0200
Subject: [PATCH] heartrate: Add support to enable notifications

This patch adds support to enable notifications for Heart Rate Measurement
characteristic value. Notifications are enabled automatically when at
least one watcher is registered and disabled otherwise.
---
 profiles/heartrate/heartrate.c | 67 ++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/profiles/heartrate/heartrate.c b/profiles/heartrate/heartrate.c
index b07a34352..dda030bbd 100644
--- a/profiles/heartrate/heartrate.c
+++ b/profiles/heartrate/heartrate.c
@@ -207,6 +207,17 @@ static void read_sensor_location_cb(guint8 status, const guint8 *pdu,
 	hr->location = value;
 }
 
+static void char_write_cb(guint8 status, const guint8 *pdu, guint16 len,
+							gpointer user_data)
+{
+	char *msg = user_data;
+
+	if (status != 0)
+		error("%s failed", msg);
+
+	g_free(msg);
+}
+
 static void discover_ccc_cb(guint8 status, const guint8 *pdu,
 						guint16 len, gpointer user_data)
 {
@@ -237,7 +248,20 @@ static void discover_ccc_cb(guint8 status, const guint8 *pdu,
 		uuid = att_get_u16(value + 2);
 
 		if (uuid == GATT_CLIENT_CHARAC_CFG_UUID) {
+			uint8_t value[2];
+			char *msg;
+
 			hr->measurement_ccc_handle = handle;
+
+			if (g_slist_length(hr->hradapter->watchers) == 0)
+				break;
+
+			att_put_u16(GATT_CLIENT_CHARAC_CFG_NOTIF_BIT, value);
+			msg = g_strdup("Enable measurement");
+
+			gatt_write_char(hr->attrib, handle, value,
+					sizeof(value), char_write_cb, msg);
+
 			break;
 		}
 	}
@@ -299,6 +323,40 @@ static void discover_char_cb(GSList *chars, guint8 status, gpointer user_data)
 	}
 }
 
+static void enable_measurement(gpointer data, gpointer user_data)
+{
+	struct heartrate *hr = data;
+	uint16_t handle = hr->measurement_ccc_handle;
+	uint8_t value[2];
+	char *msg;
+
+	if (hr->attrib == NULL || !handle)
+		return;
+
+	att_put_u16(GATT_CLIENT_CHARAC_CFG_NOTIF_BIT, value);
+	msg = g_strdup("Enable measurement");
+
+	gatt_write_char(hr->attrib, handle, value, sizeof(value),
+							char_write_cb, msg);
+}
+
+static void disable_measurement(gpointer data, gpointer user_data)
+{
+	struct heartrate *hr = data;
+	uint16_t handle = hr->measurement_ccc_handle;
+	uint8_t value[2];
+	char *msg;
+
+	if (hr->attrib == NULL || !handle)
+		return;
+
+	att_put_u16(0x0000, value);
+	msg = g_strdup("Disable measurement");
+
+	gatt_write_char(hr->attrib, handle, value, sizeof(value),
+							char_write_cb, msg);
+}
+
 static void attio_connected_cb(GAttrib *attrib, gpointer user_data)
 {
 	struct heartrate *hr = user_data;
@@ -330,6 +388,9 @@ static void watcher_exit_cb(DBusConnection *conn, void *user_data)
 
 	hradapter->watchers = g_slist_remove(hradapter->watchers, watcher);
 	g_dbus_remove_watch(conn, watcher->id);
+
+	if (g_slist_length(hradapter->watchers) == 0)
+		g_slist_foreach(hradapter->devices, disable_measurement, 0);
 }
 
 static DBusMessage *register_watcher(DBusConnection *conn, DBusMessage *msg,
@@ -355,6 +416,9 @@ static DBusMessage *register_watcher(DBusConnection *conn, DBusMessage *msg,
 	watcher->srv = g_strdup(sender);
 	watcher->path = g_strdup(path);
 
+	if (g_slist_length(hradapter->watchers) == 0)
+		g_slist_foreach(hradapter->devices, enable_measurement, 0);
+
 	hradapter->watchers = g_slist_prepend(hradapter->watchers, watcher);
 
 	DBG("heartrate watcher [%s] registered", path);
@@ -381,6 +445,9 @@ static DBusMessage *unregister_watcher(DBusConnection *conn, DBusMessage *msg,
 	hradapter->watchers = g_slist_remove(hradapter->watchers, watcher);
 	g_dbus_remove_watch(conn, watcher->id);
 
+	if (g_slist_length(hradapter->watchers) == 0)
+		g_slist_foreach(hradapter->devices, disable_measurement, 0);
+
 	DBG("heartrate watcher [%s] unregistered", path);
 
 	return dbus_message_new_method_return(msg);
-- 
2.47.3