BLE: Cordio build time configuration through mbed_lib.json

features/FEATURE_BLE/targets/TARGET_CORDIO/README.md

@@ -21,6 +21,11 @@ implementation.
     * `cordio_stack`: Headers and sources of the cordio stack 
     * `mbed_os_adaptation`: Headers of the interface responsible for the bridge
     between BLE API and the Cordio stack.
+
+## Build time configuration
+
+Build time configuration may be controlled through options set in:
+`features\FEATURE_BLE\targets\TARGET_CORDIO\mbed_lib.json`
 
 ## Documentation
 

features/FEATURE_BLE/targets/TARGET_CORDIO/mbed_lib.json

@@ -0,0 +1,58 @@
+{
+    "name": "cordio",
+    "config": {
+        "max-connections": {
+            "help": "Maximum number of connections",
+            "value": 3,
+            "macro_name": "DM_CONN_MAX"
+        },
+        "max-syncs": {
+            "help": "Maximum number of periodic advertising synchronizations",
+            "value": 1,
+            "macro_name": "DM_SYNC_MAX"
+        },
+        "max-advertising-sets": {
+            "help": "Number of supported advertising sets: must be set to 1 for legacy advertising",
+            "value": 3,
+            "macro_name": "DM_NUM_ADV_SETS"
+        },
+        "max-phys": {
+            "help": "Number of scanner and initiator PHYs (LE 1M, LE 2M and LE Coded): must be set to 1 for legacy scanner and initiator",
+            "value": 3,
+            "macro_name": "DM_NUM_PHYS"
+        },
+        "max-l2cap-channels": {
+            "help": "Maximum number of connection oriented channels",
+            "value": 8,
+            "macro_name": "L2C_COC_CHAN_MAX"
+        },
+        "max-l2cap-clients": {
+            "help": "Maximum number of connection oriented channel registered clients",
+            "value": 4,
+            "macro_name": "L2C_COC_REG_MAX"
+        },
+        "max-att-writes": {
+            "help": "Maximum number of simultaneous ATT write commands",
+            "value": 1,
+            "macro_name": "ATT_NUM_SIMUL_WRITE_CMD"
+        },
+        "max-att-notifications": {
+            "help": "Maximum number of simultaneous ATT notifications",
+            "value": 1,
+            "macro_name": "ATT_NUM_SIMUL_NTF"
+        },
+        "max-smp-devices": {
+            "help": "Max number of devices in the security database",
+            "value": 3,
+            "macro_name": "SMP_DB_MAX_DEVICES"
+        },
+        "desired-att-mtu": {
+            "help": "Desired ATT_MTU, this needs to be between 23 and 517 (inclusive).",
+            "value": 23
+        },
+        "max-prepared-writes": {
+            "help": "Number of queued prepare writes supported by server.",
+            "value": 4
+        }
+    }
+}

features/FEATURE_BLE/targets/TARGET_CORDIO/stack/cordio_stack/ble-host/sources/stack/cfg/cfg_stack.c

@@ -62,13 +62,17 @@ l2cCfg_t *pL2cCfg = &l2cCfg;
   ATT
 **************************************************************************************************/
 
+#if MBED_CONF_CORDIO_DESIRED_ATT_MTU < ATT_DEFAULT_MTU || MBED_CONF_CORDIO_DESIRED_ATT_MTU > ATT_MAX_MTU
+#error "CORDIO_CFG_DESIRED_ATT_MTU value is outside valid range"
+#endif
+
 /* Configuration structure */
 attCfg_t attCfg =
 {
-  15,                               /* ATT server service discovery connection idle timeout in seconds */
-  ATT_DEFAULT_MTU,                  /* desired ATT MTU */
-  ATT_MAX_TRANS_TIMEOUT,            /* transcation timeout in seconds */
-  4                                 /* number of queued prepare writes supported by server */
+  15,                                  /* ATT server service discovery connection idle timeout in seconds */
+  MBED_CONF_CORDIO_DESIRED_ATT_MTU,    /* desired ATT MTU */
+  ATT_MAX_TRANS_TIMEOUT,               /* transaction timeout in seconds */
+  MBED_CONF_CORDIO_MAX_PREPARED_WRITES /* number of queued prepare writes supported by server */
 };
 
 /* Configuration pointer */