From: Max Chou <max.chou@realtek.com>
To: Zenm Chen <zenmchen@gmail.com>,
"linux-bluetooth@vger.kernel.org"
<linux-bluetooth@vger.kernel.org>, Hilda Wu <hildawu@realtek.com>
Cc: Ping-Ke Shih <pkshih@realtek.com>
Subject: RE: bluetooth hci0: Direct firmware load for rtl_bt/rtl8761a_config.bin failed with error -2
Date: Thu, 30 Apr 2026 02:22:17 +0000 [thread overview]
Message-ID: <d6274785e3644bfbb0bf6a3c6a6bbff3@realtek.com> (raw)
In-Reply-To: <20260429191004.11965-1-zenmchen@gmail.com>
Hi!
The config file rtl8761a_config is not mandatory. In ic_id_table[],
.config_needed is indeed set to false. Please rest assured regarding
this matter.
If you would like to fix the warning message, it would be good to
send a patch to add rtl8761a_config.bin containing only the header
to the linux-firmware repository.
BRs,
Max
> -----Original Message-----
> From: Zenm Chen <zenmchen@gmail.com>
> Sent: Thursday, April 30, 2026 3:10 AM
> To: linux-bluetooth@vger.kernel.org; Max Chou <max.chou@realtek.com>;
> Hilda Wu <hildawu@realtek.com>
> Cc: Ping-Ke Shih <pkshih@realtek.com>
> Subject: bluetooth hci0: Direct firmware load for rtl_bt/rtl8761a_config.bin
> failed with error -2
>
>
> External mail : This email originated from outside the organization. Do not
> reply, click links, or open attachments unless you recognize the sender and
> know the content is safe.
>
>
>
> Hi,
>
> Recently I got an RTL8812AEBT card which is a WiFi5 + BT4.0 device.
> Bluetooth is working fine but I see the warning below in dmesg. It seems the
> config file rtl_bt/rtl8761a_config.bin is missing, not sure if this should be
> fixed or not.
>
> $ dmesg
> [ 171.900777] Bluetooth: Core ver 2.22
> [ 171.900818] NET: Registered PF_BLUETOOTH protocol family
> [ 171.900820] Bluetooth: HCI device and connection manager initialized
> [ 171.900825] Bluetooth: HCI socket layer initialized [ 171.900827]
> Bluetooth: L2CAP socket layer initialized [ 171.900831] Bluetooth: SCO
> socket layer initialized [ 171.934237] usbcore: registered new interface
> driver btusb [ 171.941534] Bluetooth: hci0: RTL: examining hci_ver=06
> hci_rev=000a lmp_ver=06 lmp_subver=8761 [ 171.943635] Bluetooth: hci0:
> RTL: rom_version status=0 version=3 [ 171.945657] Bluetooth: hci0: RTL:
> btrtl_initialize: key id 0 [ 171.945664] Bluetooth: hci0: RTL: loading
> rtl_bt/rtl8761a_fw.bin [ 171.949630] Bluetooth: hci0: RTL: loading
> rtl_bt/rtl8761a_config.bin [ 171.949697] bluetooth hci0: Direct firmware
> load for rtl_bt/rtl8761a_config.bin failed with error -2 [ 171.949712]
> Bluetooth: hci0: RTL: cfg_sz -2, total sz 22640 [ 172.020303] Bluetooth:
> BNEP (Ethernet Emulation) ver 1.3 [ 172.020309] Bluetooth: BNEP filters:
> protocol multicast [ 172.020314] Bluetooth: BNEP socket layer initialized
> [ 172.524780] Bluetooth: hci0: RTL: fw version 0x0e3e4380 [ 172.664330]
> Bluetooth: MGMT ver 1.22 [ 172.683252] NET: Registered PF_ALG protocol
> family [ 172.744110] Bluetooth: RFCOMM TTY layer initialized
> [ 172.744124] Bluetooth: RFCOMM socket layer initialized [ 172.744136]
> Bluetooth: RFCOMM ver 1.11
>
> $ sudo lsusb -v -d 0bda:b761
> Bus 003 Device 004: ID 0bda:b761 Realtek Semiconductor Corp. Bluetooth
> Radio Negotiated speed: Full Speed (12Mbps) Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.10
> bDeviceClass 224 Wireless
> bDeviceSubClass 1 Radio Frequency
> bDeviceProtocol 1 Bluetooth
> bMaxPacketSize0 64
> idVendor 0x0bda Realtek Semiconductor Corp.
> idProduct 0xb761 Bluetooth Radio
> bcdDevice 2.00
> iManufacturer 1 Realtek
> iProduct 2 Bluetooth Radio
> iSerial 3 00e04c000001
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 0x00b1
> bNumInterfaces 2
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup
> MaxPower 500mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 3
> bInterfaceClass 224 Wireless
> bInterfaceSubClass 1 Radio Frequency
> bInterfaceProtocol 1 Bluetooth
> iInterface 4 Bluetooth Radio
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0010 1x 16 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x02 EP 2 OUT
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 0
> bNumEndpoints 2
> bInterfaceClass 224 Wireless
> bInterfaceSubClass 1 Radio Frequency
> bInterfaceProtocol 1 Bluetooth
> iInterface 4 Bluetooth Radio
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x03 EP 3 OUT
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0000 1x 0 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0000 1x 0 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 1
> bNumEndpoints 2
> bInterfaceClass 224 Wireless
> bInterfaceSubClass 1 Radio Frequency
> bInterfaceProtocol 1 Bluetooth
> iInterface 4 Bluetooth Radio
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x03 EP 3 OUT
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0009 1x 9 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0009 1x 9 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 2
> bNumEndpoints 2
> bInterfaceClass 224 Wireless
> bInterfaceSubClass 1 Radio Frequency
> bInterfaceProtocol 1 Bluetooth
> iInterface 4 Bluetooth Radio
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x03 EP 3 OUT
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0011 1x 17 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0011 1x 17 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 3
> bNumEndpoints 2
> bInterfaceClass 224 Wireless
> bInterfaceSubClass 1 Radio Frequency
> bInterfaceProtocol 1 Bluetooth
> iInterface 4 Bluetooth Radio
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x03 EP 3 OUT
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0019 1x 25 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0019 1x 25 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 4
> bNumEndpoints 2
> bInterfaceClass 224 Wireless
> bInterfaceSubClass 1 Radio Frequency
> bInterfaceProtocol 1 Bluetooth
> iInterface 4 Bluetooth Radio
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x03 EP 3 OUT
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0021 1x 33 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0021 1x 33 bytes
> bInterval 1
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 1
> bAlternateSetting 5
> bNumEndpoints 2
> bInterfaceClass 224 Wireless
> bInterfaceSubClass 1 Radio Frequency
> bInterfaceProtocol 1 Bluetooth
> iInterface 4 Bluetooth Radio
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x03 EP 3 OUT
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0031 1x 49 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0031 1x 49 bytes
> bInterval 1
> Binary Object Store Descriptor:
> bLength 5
> bDescriptorType 15
> wTotalLength 0x000c
> bNumDeviceCaps 1
> USB 2.0 Extension Device Capability:
> bLength 7
> bDescriptorType 16
> bDevCapabilityType 2
> bmAttributes 0x00000002
> HIRD Link Power Management (LPM) Supported
> Device Status: 0x0001
> Self Powered
>
> $ sudo cat /sys/kernel/debug/usb/devices
> T: Bus=03 Lev=01 Prnt=01 Port=04 Cnt=03 Dev#= 4 Spd=12 MxCh= 0
> D: Ver= 2.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs= 1
> P: Vendor=0bda ProdID=b761 Rev= 2.00
> S: Manufacturer=Realtek
> S: Product=Bluetooth Radio
> S: SerialNumber=00e04c000001
> C:* #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=500mA
> I:* If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
> E: Ad=81(I) Atr=03(Int.) MxPS= 16 Ivl=1ms
> E: Ad=02(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms
> E: Ad=82(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms
> I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
> E: Ad=03(O) Atr=01(Isoc) MxPS= 0 Ivl=1ms
> E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms
> I: If#= 1 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
> E: Ad=03(O) Atr=01(Isoc) MxPS= 9 Ivl=1ms
> E: Ad=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms
> I: If#= 1 Alt= 2 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
> E: Ad=03(O) Atr=01(Isoc) MxPS= 17 Ivl=1ms
> E: Ad=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms
> I: If#= 1 Alt= 3 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
> E: Ad=03(O) Atr=01(Isoc) MxPS= 25 Ivl=1ms
> E: Ad=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms
> I: If#= 1 Alt= 4 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
> E: Ad=03(O) Atr=01(Isoc) MxPS= 33 Ivl=1ms
> E: Ad=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms
> I: If#= 1 Alt= 5 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
> E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms
> E: Ad=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms
next prev parent reply other threads:[~2026-04-30 2:22 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-29 19:10 bluetooth hci0: Direct firmware load for rtl_bt/rtl8761a_config.bin failed with error -2 Zenm Chen
2026-04-30 2:22 ` Max Chou [this message]
2026-05-05 7:25 ` Zenm Chen
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