我在 nanopi NEO 空气板上运行 buildroot 生成的 linux 映像（内核 4.11.2），我很难连接到我的 ruwido 遥控器。
当我使用 hcitool 扫描设备时，我可以看到它：
# hcitool lescan
LE Scan ...
<snip>
5C:F8:21:85:8E:67 ruwido
<snip>
但我无法建立连接（它就像遥控器不在这里）：
# hcitool cc 5C:F8:21:85:8E:67
Can't create connection: Input/output error
我唯一能做的就是获取一些有关它的信息：
# hcitool leinfo 5C:F8:21:85:8E:67
Requesting information ...
Handle: 64 (0x0040)
LMP Version: 4.0 (0x6) LMP Subversion: 0x140
Manufacturer: Texas Instruments Inc. (13)
Features: 0x01 0x00 0x00 0x00 0x00 0x00 0x00 0x00
我也不能使用 bluetoothctl，因为它没有检测到我的界面，即使它已初始化，bluetoothd 正在运行并且模块已加载：
# lsmod
Module Size Used by
bnep 20480 2
hci_uart 61440 1
btbcm 16384 1 hci_uart
btqca 16384 1 hci_uart
btintel 16384 1 hci_uart
bluetooth 348160 12 hci_uart,btintel,btqca,bnep,btbcm
brcmfmac 245760 0
brcmutil 16384 1 brcmfmac
sunxi_cir 16384 0
# ps -e | grep bluetooth
553 root /usr/sbin/bluetoothd
731 root grep bluetooth
# sudo hciconfig -a
hci0: Type: Primary Bus: UART
BD Address: F7:93:3E:74:CF:62 ACL MTU: 1021:8 SCO MTU: 64:1
UP RUNNING
RX bytes:12593 acl:7 sco:0 events:292 errors:0
TX bytes:2050 acl:4 sco:0 commands:155 errors:0
Features: 0xbf 0xfe 0xcf 0xfe 0xdb 0xff 0x7b 0x87
Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3
Link policy: RSWITCH SNIFF
Link mode: SLAVE ACCEPT
Name: 'NanoPi-NEO-Air'
Class: 0x000000
Service Classes: Unspecified
Device Class: Miscellaneous,
HCI Version: 4.1 (0x7) Revision: 0x0
LMP Version: 4.1 (0x7) Subversion: 0x2209
Manufacturer: Broadcom Corporation (15)
# bluetoothctl
Agent registered
[bluetooth]# power on
No default controller available
我的问题是，如何将遥控器配对并连接到电路板？不管是通过 hcitool、bluetoothctl 还是其他工具。
更新
感谢Prabhakar Lad 的评论，bluetoothctl 现在正在检测接口，但是问题仍然存在并且问题似乎已经缩小：
# rfkill unblock all
# hciconfig hci0 up
# hciconfig -a
hci0: Type: Primary Bus: UART
BD Address: AA:AA:AA:AA:AA:AA ACL MTU: 1021:8 SCO MTU: 64:1
UP RUNNING PSCAN
RX bytes:1930 acl:0 sco:0 events:101 errors:0
TX bytes:1587 acl:0 sco:0 commands:103 errors:0
Features: 0xbf 0xfe 0xcf 0xfe 0xdb 0xff 0x7b 0x87
Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3
Link policy: RSWITCH SNIFF
Link mode: SLAVE ACCEPT
Name: 'BlueZ 5.47'
Class: 0x000000
Service Classes: Unspecified
Device Class: Miscellaneous,
HCI Version: 4.1 (0x7) Revision: 0x0
LMP Version: 4.1 (0x7) Subversion: 0x2209
Manufacturer: Broadcom Corporation (15)
# bluetoothctl
[NEW] Controller F7:93:3E:74:CF:62 BlueZ 5.47 [default]
[NEW] Device 5C:F8:21:85:8E:67 ruwido
Agent registered
[bluetooth]# agent on
Agent is already registered
[bluetooth]# power on
Changing power on succeeded
[bluetooth]# scan on
Discovery started
[CHG] Controller F7:93:3E:74:CF:62 Discovering: yes
<snip>
[NEW] Device 5C:F8:21:85:8E:67 ruwido
<snip>
[bluetooth]# scan off
<snip>
[CHG] Device 5C:F8:21:85:8E:67 RSSI is nil
<snip>
[CHG] Controller F7:93:3E:74:CF:62 Discovering: no
Discovery stopped
[bluetooth]# pair 5C:F8:21:85:8E:67
Attempting to pair with 5C:F8:21:85:8E:67
[CHG] Device 5C:F8:21:85:8E:67 Connected: yes
[ruwido]# [ 501.424858] Bluetooth: hci0 unexpected SMP command 0x0b from 5c:f8:21:85:8e:67
[CHG] Device 5C:F8:21:85:8E:67 Connected: no
[bluetooth]# pair 5C:F8:21:85:8E:67
Attempting to pair with 5C:F8:21:85:8E:67
Failed to pair: org.bluez.Error.ConnectionAttemptFailed
SMP错误似乎与蓝牙低功耗安全有关，所以我应该使用不同的工具进行配对吗？
附加信息
我实际上将busybox初始化系统与我在制造商的图像中找到的蓝牙初始化脚本（即nanopi-neo-air_FriendlyCore-Xenial_4.11.2_20171113.img）一起使用并进行了调整，以便它们可以与busybox init（图像是 systemd/upstart）。
所以我有两个文件：
- /etc/init.d/S35brcm_patchram_plus：补丁固件（该卡使用 AMPAK ap6212 蓝牙/wifi 组合模块）
- /etc/init.d/S38bluetooth：启动蓝牙
我在 buildroot 2017.08.1 中使用 bluez 5.47 和以下选项：
BR2_PACKAGE_BLUEZ_TOOLS=y
# BR2_PACKAGE_BLUEZ_UTILS is not set
BR2_PACKAGE_BLUEZ5_UTILS=y
BR2_PACKAGE_BLUEZ5_UTILS_OBEX=y
BR2_PACKAGE_BLUEZ5_UTILS_CLIENT=y
BR2_PACKAGE_BLUEZ5_UTILS_DEPRECATED=y
# BR2_PACKAGE_BLUEZ5_UTILS_EXPERIMENTAL is not set
# BR2_PACKAGE_BLUEZ5_PLUGINS_HEALTH is not set
# BR2_PACKAGE_BLUEZ5_PLUGINS_MIDI is not set
# BR2_PACKAGE_BLUEZ5_PLUGINS_NFC is not set
# BR2_PACKAGE_BLUEZ5_PLUGINS_SAP is not set
BR2_PACKAGE_BLUEZ5_UTILS_TEST=y
# BR2_PACKAGE_BLUEZ5_UTILS_GATTTOOL is not set