Re: [PATCH] Bluetooth: Apply initial command workaround for more Intel chips

From: Paul Menzel <pmenzel@molgen.mpg.de>
To: Takashi Iwai <tiwai@suse.de>
Cc: Marcel Holtmann <marcel@holtmann.org>,
	Johan Hedberg <johan.hedberg@gmail.com>,
	Luiz Augusto von Dentz <luiz.dentz@gmail.com>,
	Tedd Ho-Jeong An <tedd.an@intel.com>,
	linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org
Subject: Re: [PATCH] Bluetooth: Apply initial command workaround for more Intel chips
Date: Thu, 2 Dec 2021 17:58:01 +0100	[thread overview]
Message-ID: <6191d067-4eae-4776-5840-1d826113a6d5@molgen.mpg.de> (raw)
In-Reply-To: <s5h7dcnt0lp.wl-tiwai@suse.de>

Dear Takashi,

Am 02.12.21 um 17:47 schrieb Takashi Iwai:
> On Thu, 02 Dec 2021 17:32:14 +0100, Paul Menzel wrote:

>> Am 02.12.21 um 17:22 schrieb Takashi Iwai:
>>> It seems that a few more Intel chips require the workaround for the
>>> broken initial command.  At least, per openSUSE Bugzilla reports,
>>> 8087:0a2a and 8087:0026 need BTUSB_INTEL_BROKEN_INITIAL_NCMD flag.
>>>
>>> Fixes: 83f2dafe2a62 ("Bluetooth: btintel: Refactoring setup routine for legacy ROM sku")
>>> Buglink: https://bugzilla.opensuse.org/show_bug.cgi?id=1193124
>>> Signed-off-by: Takashi Iwai <tiwai@suse.de>
>>>
>>
>> […]
>>
>> I have a Dell Latitude E7250 with
>>
>>      Bus 001 Device 003: ID 8087:0a2a Intel Corp. Bluetooth wireless interface
>>
>> and Bluetooth seems to work fine minus some Linux warnings [1] and a
>> problem transferring greater than some bytes files with the Nokia N9
>> [2].
>>
>> Linux 5.16-rc3, Dell Inc. Latitude E7250/0TVD2T, BIOS A19 01/23/2018:
>>
>> ```
>> $ sudo dmesg | grep -i bluet
>> [    8.173417] calling  bt_init+0x0/0xb3 [bluetooth] @ 301
>> [    8.173439] Bluetooth: Core ver 2.22
>> [    8.173463] NET: Registered PF_BLUETOOTH protocol family
>> [    8.173464] Bluetooth: HCI device and connection manager initialized
>> [    8.173467] Bluetooth: HCI socket layer initialized
>> [    8.173470] Bluetooth: L2CAP socket layer initialized
>> [    8.173473] Bluetooth: SCO socket layer initialized
>> [    8.173475] initcall bt_init+0x0/0xb3 [bluetooth] returned 0 after 35 usecs
>> [    8.216875] Bluetooth: hci0: Legacy ROM 2.5 revision 1.0 build 3 week 17 2014
>> [    8.233515] bluetooth hci0: firmware: direct-loading firmware intel/ibt-hw-37.8.10-fw-1.10.3.11.e.bseq
>> [    8.233520] Bluetooth: hci0: Intel Bluetooth firmware file: intel/ibt-hw-37.8.10-fw-1.10.3.11.e.bseq
>> [    8.540884] Bluetooth: hci0: unexpected event for opcode 0xfc2f
>> [    8.558942] Bluetooth: hci0: Intel BT fw patch 0x32 completed & activated
>> ```
> 
> Thanks, so this seems depending on the hardware, maybe a subtle
> difference matters.  As far as I read the code changes, the workaround
> was applied in the past unconditionally, so it must be fairly safe
> even if the chip works as is.

Maybe add that to the commit message?

> Or, for avoiding the unnecessarily application of the workaround,
> should it be changed as a fallback after the failure at the first
> try...?

Reading through the openSUSE Bugzilla issue, the failure is:

     Bluetooth: hci0: Reading Intel version command failed (-110)
     Bluetooth: hci0: command 0xfc05 tx timeout

I couldn’t find the report for 8087:0a2a in the issue. Can you check, 
what firmware is used?

If the functionality of 5.14 is restored by your patch, then it should 
work I guess. I didn’t use Bluetooth for file transfers in the past and 
only for connecting to external speakers.

Kind regards,

Paul