Diff: nordic/ble/ble_conn_params.cpp

Revision:

0:eff01767de02

Child:

42:120a96d10f90

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/nordic/ble/ble_conn_params.cpp	Wed Mar 26 14:38:17 2014 +0000
@@ -0,0 +1,322 @@
+/* Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
+ *
+ * The information contained herein is property of Nordic Semiconductor ASA.
+ * Terms and conditions of usage are described in detail in NORDIC
+ * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
+ *
+ * Licensees are granted free, non-transferable use of the information. NO
+ * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
+ * the file.
+ *
+ */
+
+#include "ble_conn_params.h"
+#include <stdlib.h>
+#include "nordic_common.h"
+#include "ble_hci.h"
+#include "app_timer.h"
+#include "ble_srv_common.h"
+#include "app_util.h"
+
+
+static ble_conn_params_init_t m_conn_params_config;     /**< Configuration as specified by the application. */
+static ble_gap_conn_params_t  m_preferred_conn_params;  /**< Connection parameters preferred by the application. */
+static uint8_t                m_update_count;           /**< Number of Connection Parameter Update messages that has currently been sent. */
+static uint16_t               m_conn_handle;            /**< Current connection handle. */
+static ble_gap_conn_params_t  m_current_conn_params;    /**< Connection parameters received in the most recent Connect event. */
+static app_timer_id_t         m_conn_params_timer_id;   /**< Connection parameters timer. */
+
+static bool m_change_param = false;
+
+static bool is_conn_params_ok(ble_gap_conn_params_t * p_conn_params)
+{
+    // Check if interval is within the acceptable range.
+    // NOTE: Using max_conn_interval in the received event data because this contains
+    //       the client's connection interval.
+    if (
+        (p_conn_params->max_conn_interval >= m_preferred_conn_params.min_conn_interval)
+        && 
+        (p_conn_params->max_conn_interval <= m_preferred_conn_params.max_conn_interval)
+    )
+    {
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+
+static void update_timeout_handler(void * p_context)
+{
+    UNUSED_PARAMETER(p_context);
+
+    if (m_conn_handle != BLE_CONN_HANDLE_INVALID)
+    {
+        // Check if we have reached the maximum number of attempts
+        m_update_count++;
+        if (m_update_count <= m_conn_params_config.max_conn_params_update_count)
+        {
+            uint32_t err_code;
+            
+            // Parameters are not ok, send connection parameters update request.
+            err_code = sd_ble_gap_conn_param_update(m_conn_handle, &m_preferred_conn_params);
+            if ((err_code != NRF_SUCCESS) && (m_conn_params_config.error_handler != NULL))
+            {
+                m_conn_params_config.error_handler(err_code);
+            }
+        }
+        else
+        {
+            m_update_count = 0;
+            
+            // Negotiation failed, disconnect automatically if this has been configured
+            if (m_conn_params_config.disconnect_on_fail)
+            {
+                uint32_t err_code;
+                
+                err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_CONN_INTERVAL_UNACCEPTABLE);
+                if ((err_code != NRF_SUCCESS) && (m_conn_params_config.error_handler != NULL))
+                {
+                    m_conn_params_config.error_handler(err_code);
+                }
+            }
+            
+            // Notify the application that the procedure has failed
+            if (m_conn_params_config.evt_handler != NULL)
+            {
+                ble_conn_params_evt_t evt;
+                
+                evt.evt_type = BLE_CONN_PARAMS_EVT_FAILED;
+                m_conn_params_config.evt_handler(&evt);
+            }
+        }
+    }
+}
+
+
+uint32_t ble_conn_params_init(const ble_conn_params_init_t * p_init)
+{
+    uint32_t err_code;
+    
+    m_conn_params_config = *p_init;
+    m_change_param = false;
+    if (p_init->p_conn_params != NULL)
+    {
+        m_preferred_conn_params = *p_init->p_conn_params;
+        
+        // Set the connection params in stack
+        err_code = sd_ble_gap_ppcp_set(&m_preferred_conn_params);
+        if (err_code != NRF_SUCCESS)
+        {
+            return err_code;
+        }
+    }
+    else
+    {
+        // Fetch the connection params from stack
+        err_code = sd_ble_gap_ppcp_get(&m_preferred_conn_params);
+        if (err_code != NRF_SUCCESS)
+        {
+            return err_code;
+        }
+    }
+
+    m_conn_handle  = BLE_CONN_HANDLE_INVALID;
+    m_update_count = 0;
+    
+    return app_timer_create(&m_conn_params_timer_id,
+                            APP_TIMER_MODE_SINGLE_SHOT,
+                            update_timeout_handler);
+}
+
+
+uint32_t ble_conn_params_stop(void)
+{
+    return app_timer_stop(m_conn_params_timer_id);
+}
+
+
+static void conn_params_negotiation(void)
+{
+    // Start negotiation if the received connection parameters are not acceptable
+    if (!is_conn_params_ok(&m_current_conn_params))
+    {
+        uint32_t err_code;
+        uint32_t timeout_ticks;
+        
+        if (m_change_param)
+        {
+            // Notify the application that the procedure has failed
+            if (m_conn_params_config.evt_handler != NULL)
+            {
+                ble_conn_params_evt_t evt;
+                
+                evt.evt_type = BLE_CONN_PARAMS_EVT_FAILED;
+                m_conn_params_config.evt_handler(&evt);
+            }
+        }
+        else
+        {
+            if (m_update_count == 0)
+            {
+                // First connection parameter update
+                timeout_ticks = m_conn_params_config.first_conn_params_update_delay;
+            }
+            else
+            {
+                timeout_ticks = m_conn_params_config.next_conn_params_update_delay;
+            }
+
+            err_code = app_timer_start(m_conn_params_timer_id, timeout_ticks, NULL);
+            if ((err_code != NRF_SUCCESS) && (m_conn_params_config.error_handler != NULL))
+            {
+                m_conn_params_config.error_handler(err_code);
+            }
+        }
+    }
+    else
+    {
+        // Notify the application that the procedure has succeded
+        if (m_conn_params_config.evt_handler != NULL)
+        {
+            ble_conn_params_evt_t evt;
+            
+            evt.evt_type = BLE_CONN_PARAMS_EVT_SUCCEEDED;
+            m_conn_params_config.evt_handler(&evt);
+        }
+    }
+    m_change_param = false;
+}
+
+
+static void on_connect(ble_evt_t * p_ble_evt)
+{
+    // Save connection parameters
+    m_conn_handle         = p_ble_evt->evt.gap_evt.conn_handle;
+    m_current_conn_params = p_ble_evt->evt.gap_evt.params.connected.conn_params;
+    m_update_count        = 0;  // Connection parameter negotiation should re-start every connection
+    
+    // Check if we shall handle negotiation on connect
+    if (m_conn_params_config.start_on_notify_cccd_handle == BLE_GATT_HANDLE_INVALID)
+    {
+        conn_params_negotiation();
+    }
+}
+
+
+static void on_disconnect(ble_evt_t * p_ble_evt)
+{
+    uint32_t err_code;
+
+    m_conn_handle = BLE_CONN_HANDLE_INVALID;
+
+    // Stop timer if running
+    m_update_count = 0; // Connection parameters updates should happen during every connection
+    
+    err_code = app_timer_stop(m_conn_params_timer_id);
+    if ((err_code != NRF_SUCCESS) && (m_conn_params_config.error_handler != NULL))
+    {
+        m_conn_params_config.error_handler(err_code);
+    }
+}
+
+
+static void on_write(ble_evt_t * p_ble_evt)
+{
+    ble_gatts_evt_write_t * p_evt_write = &p_ble_evt->evt.gatts_evt.params.write;
+
+    // Check if this the correct CCCD
+    if (
+        (p_evt_write->handle == m_conn_params_config.start_on_notify_cccd_handle)
+        &&
+        (p_evt_write->len == 2)
+    )
+    {
+        // Check if this is a 'start notification'
+        if (ble_srv_is_notification_enabled(p_evt_write->data))
+        {
+            // Do connection parameter negotiation if necessary
+            conn_params_negotiation();
+        }
+        else
+        {
+            uint32_t err_code;
+
+            // Stop timer if running
+            err_code = app_timer_stop(m_conn_params_timer_id);
+            if ((err_code != NRF_SUCCESS) && (m_conn_params_config.error_handler != NULL))
+            {
+                m_conn_params_config.error_handler(err_code);
+            }
+        }
+    }
+}
+
+
+static void on_conn_params_update(ble_evt_t * p_ble_evt)
+{
+    // Copy the parameters
+    m_current_conn_params = p_ble_evt->evt.gap_evt.params.conn_param_update.conn_params;
+
+    conn_params_negotiation();
+}
+
+
+void ble_conn_params_on_ble_evt(ble_evt_t * p_ble_evt)
+{
+    switch (p_ble_evt->header.evt_id)
+    {
+        case BLE_GAP_EVT_CONNECTED:
+            on_connect(p_ble_evt);
+            break;
+            
+        case BLE_GAP_EVT_DISCONNECTED:
+            on_disconnect(p_ble_evt);
+            break;
+            
+        case BLE_GATTS_EVT_WRITE:
+            on_write(p_ble_evt);
+            break;
+            
+        case BLE_GAP_EVT_CONN_PARAM_UPDATE:
+            on_conn_params_update(p_ble_evt);
+            break;
+            
+        default:
+            // No implementation needed.
+           break;
+    }
+}
+
+uint32_t ble_conn_params_change_conn_params(ble_gap_conn_params_t *new_params)
+{
+    uint32_t err_code;
+
+    m_preferred_conn_params = *new_params;
+    // Set the connection params in stack
+    err_code = sd_ble_gap_ppcp_set(&m_preferred_conn_params);
+    if (err_code == NRF_SUCCESS)
+    {
+        if (!is_conn_params_ok(&m_current_conn_params))
+        {
+            m_change_param = true;
+            err_code = sd_ble_gap_conn_param_update(m_conn_handle, &m_preferred_conn_params);
+            m_update_count = 1;
+        }
+        else
+        {
+            // Notify the application that the procedure has succeded
+            if (m_conn_params_config.evt_handler != NULL)
+            {
+                ble_conn_params_evt_t evt;
+                
+                evt.evt_type = BLE_CONN_PARAMS_EVT_SUCCEEDED;
+                m_conn_params_config.evt_handler(&evt);
+            }
+            err_code = NRF_SUCCESS;
+        }
+    }
+    return err_code;
+}