extmod/modbluetooth: Add optional 4th arg to gattc_write for write mode.

This allows the user to explicitly select the behaviour of the write to the
remote peripheral.  This is needed for peripherals that have
characteristics with WRITE_NO_RESPONSE set (instead of normal WRITE).  The
function's signature is now:

    BLE.gattc_write(conn_handle, value_handle, data, mode=0)

mode=0 means write without response, while mode=1 means write with
response.  The latter was the original behaviour so this commit is a change
in behaviour of this method, and one should specify 1 as the 4th argument
to get back the old behaviour.

In the future there could be more modes supported, such as long writes.

1 files changed, 6 insertions, 2 deletions

diff --git a/extmod/modbluetooth.c b/extmod/modbluetooth.c
index 2293e0367..74f73c1f2 100644
--- a/extmod/modbluetooth.c
+++ b/extmod/modbluetooth.c
@@ -641,9 +641,13 @@ STATIC mp_obj_t bluetooth_ble_gattc_write(size_t n_args, const mp_obj_t *args) {
     mp_buffer_info_t bufinfo = {0};
     mp_get_buffer_raise(data, &bufinfo, MP_BUFFER_READ);
     size_t len = bufinfo.len;
-    return bluetooth_handle_errno(mp_bluetooth_gattc_write(conn_handle, value_handle, bufinfo.buf, &len));
+    unsigned int mode = MP_BLUETOOTH_WRITE_MODE_NO_RESPONSE;
+    if (n_args == 5) {
+        mode = mp_obj_get_int(args[4]);
+    }
+    return bluetooth_handle_errno(mp_bluetooth_gattc_write(conn_handle, value_handle, bufinfo.buf, &len, mode));
 }
-STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(bluetooth_ble_gattc_write_obj, 4, 4, bluetooth_ble_gattc_write);
+STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(bluetooth_ble_gattc_write_obj, 4, 5, bluetooth_ble_gattc_write);
 
 #endif // MICROPY_PY_BLUETOOTH_ENABLE_CENTRAL_MODE