From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3DEF021FF55; Tue, 9 Dec 2025 00:17:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765239430; cv=none; b=aFcTanHsxQ1r8csV+eU9Adn0qrp7pn6GpGDD6u77Wn7O7UQnT71x80SKSWfnAkK7W70YbNpoZEmkdguGwy5a/G1GQu5QKqghpp6RfmI9vwn618/a8czKRcqPTU2fc9HniJfkLtOnG6ykW4vpggN6So+OrBkJl/ZYUJ8l0gXIq5M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765239430; c=relaxed/simple; bh=mA14ruNO3szL9g1X8tOTLj3a3VtsH9RLuJW+L+/RCmk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kqkY6Ar465sbn2suHbU8HGXCPjJLoVKjc5pgXV/UdpYk6dRzFDqCT/RffhXP92NVEVjoIioWbeBeTCZmvWNwAYrUP3rbqgpAbfWm4O10/TR0MGPPj2rTIVa61H+fhA7ITxVl+5IKugZlmZenRVSKCBm3jHRsCl8ISw+OqlrehuA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=olM3tFxn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="olM3tFxn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EAFB7C4CEF1; Tue, 9 Dec 2025 00:17:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765239430; bh=mA14ruNO3szL9g1X8tOTLj3a3VtsH9RLuJW+L+/RCmk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=olM3tFxnaoxotIvmzvIRirMGeZeIY+hJVnE9K0Xs6Wu8iHYYF5ix8icaFtiG9t8pr tCOC9kX/9iq/bvc5XYPr0YWoXmcIOLMPoLy5p1lnaxYYFKeAZINZC+OAv9ZhOBilWO VljPMTaNRXDZ6i4EEHbt14FFqobofcgnc6ycsR0bV7qZtgCJTkEhICDgk23VaNh3nZ by69/lUBQ68/Umz2lfVgjpUSG1UDXfdWzik1Zb8ND2KiNd/51sC9LsUV1aFcYhex72 Aa0ajiFrmM/5SjCB6zNUMJ1HyfXExkGK1R6Kmtl0YQRzbIkC4mdjaTY8KS9qJQkR3P 1gAFf3glEGn0A== From: Sasha Levin To: patches@lists.linux.dev, stable@vger.kernel.org Cc: Chris Lu , Paul Menzel , Luiz Augusto von Dentz , Sasha Levin , marcel@holtmann.org, luiz.dentz@gmail.com, matthias.bgg@gmail.com, angelogioacchino.delregno@collabora.com, linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Subject: [PATCH AUTOSEL 6.18-6.12] Bluetooth: btusb: MT7922: Add VID/PID 0489/e170 Date: Mon, 8 Dec 2025 19:15:09 -0500 Message-ID: <20251209001610.611575-17-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251209001610.611575-1-sashal@kernel.org> References: <20251209001610.611575-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-bluetooth@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.18 Content-Transfer-Encoding: 8bit From: Chris Lu [ Upstream commit 5a6700a31c953af9a17a7e2681335f31d922614d ] Add VID 0489 & PID e170 for MediaTek MT7922 USB Bluetooth chip. The information in /sys/kernel/debug/usb/devices about the Bluetooth device is listed as the below. T: Bus=06 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=480 MxCh= 0 D: Ver= 2.10 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1 P: Vendor=0489 ProdID=e170 Rev= 1.00 S: Manufacturer=MediaTek Inc. S: Product=Wireless_Device S: SerialNumber=000000000 C:* #Ifs= 3 Cfg#= 1 Atr=e0 MxPwr=100mA A: FirstIf#= 0 IfCount= 3 Cls=e0(wlcon) Sub=01 Prot=01 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=125us E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms E: Ad=03(O) 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=83(I) Atr=01(Isoc) MxPS= 9 Ivl=1ms E: Ad=03(O) 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=83(I) Atr=01(Isoc) MxPS= 17 Ivl=1ms E: Ad=03(O) 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=83(I) Atr=01(Isoc) MxPS= 25 Ivl=1ms E: Ad=03(O) 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=83(I) Atr=01(Isoc) MxPS= 33 Ivl=1ms E: Ad=03(O) 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=83(I) Atr=01(Isoc) MxPS= 49 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 49 Ivl=1ms I: If#= 1 Alt= 6 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb E: Ad=83(I) Atr=01(Isoc) MxPS= 63 Ivl=1ms E: Ad=03(O) Atr=01(Isoc) MxPS= 63 Ivl=1ms I:* If#= 2 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=(none) E: Ad=8a(I) Atr=03(Int.) MxPS= 64 Ivl=125us E: Ad=0a(O) Atr=03(Int.) MxPS= 64 Ivl=125us I: If#= 2 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=(none) E: Ad=8a(I) Atr=03(Int.) MxPS= 512 Ivl=125us E: Ad=0a(O) Atr=03(Int.) MxPS= 512 Ivl=125us Signed-off-by: Chris Lu Reviewed-by: Paul Menzel Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- LLM Generated explanations, may be completely bogus: ## Analysis: Bluetooth: btusb: MT7922: Add VID/PID 0489/e170 ### 1. COMMIT MESSAGE ANALYSIS **Subject**: Adding a new USB Vendor ID (VID) 0x0489 and Product ID (PID) 0xe170 for a MediaTek MT7922 Bluetooth chip. **Key Tags**: - Signed-off-by: Chris Lu from MediaTek (the chip vendor) - Reviewed-by: Paul Menzel - Signed-off-by: Luiz Augusto von Dentz (Bluetooth maintainer) No explicit `Cc: stable@vger.kernel.org` tag, but this is common for device ID additions which are often handled implicitly. ### 2. CODE CHANGE ANALYSIS The change is a 2-line addition to the `quirks_table[]` array: ```c { USB_DEVICE(0x0489, 0xe170), .driver_info = BTUSB_MEDIATEK | BTUSB_WIDEBAND_SPEECH }, ``` This simply registers a new USB device ID with existing driver flags (`BTUSB_MEDIATEK` and `BTUSB_WIDEBAND_SPEECH`) that are already fully supported. The btusb driver already contains full MT7922 support - this just adds another VID/PID variant to the recognition table. ### 3. CLASSIFICATION This is a **NEW DEVICE ID** addition - one of the explicitly allowed exception categories for stable backports: - Adding a USB VID/PID to an existing, well-tested driver - Trivial one-entry addition to a device table - The driver code for MT7922 already exists; only recognition is missing ### 4. SCOPE AND RISK ASSESSMENT | Metric | Assessment | |--------|------------| | Lines changed | 2 | | Files touched | 1 | | Complexity | Minimal - static table entry | | Risk | **Extremely low** | The change can only affect USB devices with VID=0x0489 and PID=0xe170. Users without this specific hardware are completely unaffected. This is about as low-risk as a kernel patch can be. ### 5. USER IMPACT - **Affected users**: Those with this specific MediaTek MT7922 Bluetooth variant - **Severity without fix**: Bluetooth hardware is completely non- functional (driver doesn't recognize the device) - **Impact**: HIGH for affected users - their Bluetooth doesn't work at all The commit includes detailed `/sys/kernel/debug/usb/devices` output showing real hardware, indicating this comes from actual user/vendor testing. ### 6. STABILITY INDICATORS - Authored by MediaTek (chip vendor) with direct hardware knowledge - Reviewed by community member - Signed off by the Bluetooth subsystem maintainer - Follows established pattern of many similar MT7922 device ID entries visible in the diff context ### 7. DEPENDENCY CHECK - **No dependencies**: This is a self-contained table entry addition - **Existing support**: The BTUSB_MEDIATEK and BTUSB_WIDEBAND_SPEECH flags and MT7922 support code exist in all recent stable trees - **Clean application**: Should apply cleanly to any stable tree that has MT7922 support ### CONCLUSION This commit is a textbook example of what SHOULD be backported to stable: 1. **Falls under Device ID Exception**: Explicitly allowed category for stable 2. **Fixes Real User Problem**: Enables Bluetooth hardware that would otherwise be completely non-functional 3. **Minimal Risk**: 2-line table entry addition, cannot break anything else 4. **No New Features**: Just enables existing driver for new hardware variant 5. **Well-Reviewed**: Proper sign-offs from vendor and maintainer 6. **Clear Benefit**: Users with this hardware get working Bluetooth The lack of explicit stable tag is typical for device ID additions - stable maintainers routinely accept these. The benefit (enabling hardware) far outweighs the near-zero risk. **YES** drivers/bluetooth/btusb.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index 595afeff4afb5..9b199da1c0d67 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -687,6 +687,8 @@ static const struct usb_device_id quirks_table[] = { BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x0489, 0xe153), .driver_info = BTUSB_MEDIATEK | BTUSB_WIDEBAND_SPEECH }, + { USB_DEVICE(0x0489, 0xe170), .driver_info = BTUSB_MEDIATEK | + BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x04ca, 0x3804), .driver_info = BTUSB_MEDIATEK | BTUSB_WIDEBAND_SPEECH }, { USB_DEVICE(0x04ca, 0x38e4), .driver_info = BTUSB_MEDIATEK | -- 2.51.0