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

From: Takashi Iwai <tiwai@suse.de>
To: Paul Menzel <pmenzel@molgen.mpg.de>
Cc: Takashi Iwai <tiwai@suse.de>,
	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: Fri, 03 Dec 2021 08:24:34 +0100	[thread overview]
Message-ID: <s5h4k7qtakt.wl-tiwai@suse.de> (raw)
In-Reply-To: <6191d067-4eae-4776-5840-1d826113a6d5@molgen.mpg.de>

On Thu, 02 Dec 2021 17:58:01 +0100,
Paul Menzel wrote:
> 
> 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?

Maybe, if the upstream agrees with that.  More comments needed from
Intel, as it's a kind of black magic.

> > 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.

There two different machines in the report.

> Can you check,
> what firmware is used?

It's the place before loading the firmware, so the firmware version
doesn't matter.

thanks,

Takashi