diff --git a/nimble/host/include/host/ble_hs_hci.h b/nimble/host/include/host/ble_hs_hci.h
index 4b3607457..e10b8e62a 100644
--- a/nimble/host/include/host/ble_hs_hci.h
+++ b/nimble/host/include/host/ble_hs_hci.h
@@ -20,17 +20,79 @@
 #ifndef H_BLE_HS_HCI_
 #define H_BLE_HS_HCI_
 
+/**
+ * @brief Bluetooth Host HCI utils
+ * @defgroup bt_host_hci Bluetooth Host HCI utils
+ * @ingroup bt_host
+ * @{
+ */
+
 #include <inttypes.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+/**
+ * Queries the controller for the channel map used with the specified
+ * connection.  The channel map is represented as an array of five bytes, with
+ * each bit corresponding to an individual channel.  The array is interpreted
+ * as little-endian, such that:
+ *     map[0] & 0x01 --> Channel 0.
+ *     map[0] & 0x02 --> Channel 1.
+ *     ...
+ *     map[1] & 0x01 --> Channel 8.
+ *
+ * As there are 37 channels, only the first 37 bits get written.
+ *
+ * If a bit is 1, the corresponding channel is used.  Otherwise, the channel is
+ * unused.
+ *
+ * @param conn_handle           The handle of the connection whose channel map
+ *                                  is being read.
+ * @param out_chan_map          On success, the retrieved channel map gets
+ *                                  written here.  This buffer must have a size
+ *                                  >= 5 bytes.
+ *
+ * @return                      0 on success;
+ *                              A BLE host HCI return code if the controller
+ *                                  rejected the request;
+ *                              A BLE host core return code on unexpected
+ *                                  error.
+ */
 int ble_hs_hci_read_chan_map(uint16_t conn_handle, uint8_t *out_chan_map);
+
+/**
+ * Instructs the controller to use the specified channel map.  The channel map
+ * is represented as an array of five bytes, with each bit corresponding to an
+ * individual channel.  The array is interpreted as little-endian, such that:
+ *     map[0] & 0x01 --> Channel 0.
+ *     map[0] & 0x02 --> Channel 1.
+ *     ...
+ *     map[1] & 0x01 --> Channel 8.
+ *
+ * As there are 37 channels, only the first 37 bits should be written are used.
+ *
+ * If a bit is 1, the corresponding channel can be used.  Otherwise, the
+ * channel should not be used.
+ *
+ * @param chan_map              The channel map to configure.  This buffer
+ *                                  should have a size of 5 bytes.
+ *
+ * @return                      0 on success;
+ *                              A BLE host HCI return code if the controller
+ *                                  rejected the request;
+ *                              A BLE host core return code on unexpected
+ *                                  error.
+ */
 int ble_hs_hci_set_chan_class(const uint8_t *chan_map);
 
 #ifdef __cplusplus
 }
 #endif
 
+/**
+ * @}
+ */
+
 #endif
diff --git a/nimble/host/src/ble_hs_hci_util.c b/nimble/host/src/ble_hs_hci_util.c
index fabf65f1a..e99dcbdff 100644
--- a/nimble/host/src/ble_hs_hci_util.c
+++ b/nimble/host/src/ble_hs_hci_util.c
@@ -197,33 +197,6 @@ ble_hs_hci_util_data_hdr_strip(struct os_mbuf *om,
     return 0;
 }
 
-/**
- * Queries the controller for the channel map used with the specified
- * connection.  The channel map is represented as an array of five bytes, with
- * each bit corresponding to an individual channel.  The array is interpreted
- * as little-endian, such that:
- *     map[0] & 0x01 --> Channel 0.
- *     map[0] & 0x02 --> Channel 1.
- *     ...
- *     map[1] & 0x01 --> Channel 8.
- *
- * As there are 37 channels, only the first 37 bits get written.
- *
- * If a bit is 1, the corresponding channel is used.  Otherwise, the channel is
- * unused.
- *
- * @param conn_handle           The handle of the connection whose channel map
- *                                  is being read.
- * @param out_chan_map          On success, the retrieved channel map gets
- *                                  written here.  This buffer must have a size
- *                                  >= 5 bytes.
- *
- * @return                      0 on success;
- *                              A BLE host HCI return code if the controller
- *                                  rejected the request;
- *                              A BLE host core return code on unexpected
- *                                  error.
- */
 int
 ble_hs_hci_read_chan_map(uint16_t conn_handle, uint8_t *out_chan_map)
 {
@@ -256,29 +229,6 @@ ble_hs_hci_read_chan_map(uint16_t conn_handle, uint8_t *out_chan_map)
     return 0;
 }
 
-/**
- * Instructs the controller to use the specified channel map.  The channel map
- * is represented as an array of five bytes, with each bit corresponding to an
- * individual channel.  The array is interpreted as little-endian, such that:
- *     map[0] & 0x01 --> Channel 0.
- *     map[0] & 0x02 --> Channel 1.
- *     ...
- *     map[1] & 0x01 --> Channel 8.
- *
- * As there are 37 channels, only the first 37 bits should be written are used.
- *
- * If a bit is 1, the corresponding channel can be used.  Otherwise, the
- * channel should not be used.
- *
- * @param chan_map              The channel map to configure.  This buffer
- *                                  should have a size of 5 bytes.
- *
- * @return                      0 on success;
- *                              A BLE host HCI return code if the controller
- *                                  rejected the request;
- *                              A BLE host core return code on unexpected
- *                                  error.
- */
 int
 ble_hs_hci_set_chan_class(const uint8_t *chan_map)
 {