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 044664086A for ; Fri, 8 Mar 2024 14:04:37 +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=1709906678; cv=none; b=cLSBCyypwSNtoACx2T2xb1ZYZySScbElcazsIv1MGaD1+rhEIJzUMAqHqVXL6OuYKQVk7Xbjevu/8wczS0N4swTaEodRC46J53cGGd9tyQgY2NR5NqS6lySIzzZz7A0+Zo4Qsb0UwwXnVXfXOlCwnbAUaoMQsy2RF8WMKE0agho= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709906678; c=relaxed/simple; bh=gf6i8cDQidksLDZJQEfsR2JezU6Lt7Garjdo7I3tknY=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=sIzrnhtaGJG91gokdYSiHB40sqA5WKvAD3ZXM/tBzwJVWWc4EXMOAkv7tmfAizZKh+gZP+S+Pp7byk0hsa+Qzs+EsM40RGVQUx944fqx0s5DQrfSt653H2dmOLe/wjxvwuxsx16vSJwXo+Ik24sso1+VmIU8j0kYNhU/Fk7XIaY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=d4v2elPw; 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="d4v2elPw" Received: by smtp.kernel.org (Postfix) with ESMTPS id 9FCD9C433F1 for ; Fri, 8 Mar 2024 14:04:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709906677; bh=gf6i8cDQidksLDZJQEfsR2JezU6Lt7Garjdo7I3tknY=; h=From:To:Subject:Date:In-Reply-To:References:From; b=d4v2elPwWHuMDrVU7eBri0pyhPeOrgh0lx5OHhLZKv7+coxUE5k6kEkj70JnsMAOR zXeimk+zL+K+Vocys8rK/LxWwg/ZtXZt6iLt56NKGjhLi0FgTc6TF3cBWogicMduIF OFGvXMfAXRV5hfCvibUyVMkTXMkpP/jEz7Ml0ZkxyI04ITisojfMq1gCt/1zUGgBSk xREStfLLNxEslrlKLXKNS6cJB81wBNoxCAsZI7GBipVnceNDsR8DbkRS0WgD6Vd71C 8nRR/42L/3TPhlqtnJyY2D+KbDj6vzsOgSIcm4x+iD2CzeSnzCj3assY8FkUH6KN3G Pt8xNXuGrF9Zw== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 87322C53BD0; Fri, 8 Mar 2024 14:04:36 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 218544] not enough bandwidth, synaptics hi-res audio duplex audio Date: Fri, 08 Mar 2024 14:04:36 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: USB X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: ibmalone@gmail.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D218544 --- Comment #12 from Ian Malone (ibmalone@gmail.com) --- Okay, I think we may have reached a dead end. Using wireplumber (creating r= ules in ~/.config/wireplumber/main.lua.d) it's possible to manipulate the audio formats that pipewire will use for a device, so I can independently request= the 16 bit mode for the input and output streams. The bandwidth profiles for th= ose are as follows (wMaxPacketSize is for the in/out interface descriptor with = the corresponding bBitResolution as reported by lsusb -v): in (48kHz) 16bit, expected wMaxpacket size 192bytes bandwidth: 1-1.1 ep 81: 159 @ 0.2+1 mask f004 uframes 125 34 24bit, expected wMaxPacketSize 288bytes bandwidth: 1-1.1 ep 81: 234 @ 0.2+1 mask f004 uframes 125 109 out (48kHz) 16bit, expected wMaxPacketSize 768bytes (?!) bandwidth: 1-1.1 ep 01: 608 @ 0.1+1 mask 003e uframes 125 125 125 125 108 24bit, expected wMaxPacketSize 458bytes bandwidth: 1-1.1 ep 01: 458 @ 0.2+1 mask 003c uframes 125 125 125 83 There's also the HID endpoint (unbinding doesn't seem to remove the bandwid= th usage) expected wMaxPacketSize 35bytes: 1-1.1 ep 84: 39 @ 0.0+1 mask 1c01 The bandwidth to wMaxPacketSize ratio is approximately the same for all str= eams (1.2-1.3, 1.11 for the HID I guess slightly different overheads). Following the rules that ehci-sched.c sets out, this can't be met: max_tt_usecs[] =3D { 125, 125, 125, 125, 125, 125, 30, 0 }; and: /* special case for isoc transfers larger than 125us: * the first and each subsequent fully used uframe * must be empty, so as to not illegally delay * already scheduled transactions */ The minimum bandwidth configuration is: out(24b) 125 125 125 83 in (16b) 125 34 hid 39 And there is no way to block them such that 30 in microframe 7 isn't exceed= ed. 125 125 125 83 125 34 39 0 etc. Unless it's legal to schedule the hid into microframe 6 after the audio inp= ut as its final microframe is not fully used? A final point of interest is 16bit output, wMaxPacketSize 768bytes. 24 bit output has allowed frequencies 44.1kHz, 48kHz, 96kHz, 2 channels. 16 bit has 8kHz, 16kHz, 32kHz, 441.kHz, 48kHz, 96kHz. Input 24 and 16 bit have only 48= kHz and 44.1kHz, 2 channels. wMaxPacketSize / (Max sampling frequency * sample bytes * channels ) in16b 192 / (48kHz * 2 * 2) =3D 1ms in24b 288 / (48kHz * 3 * 2) =3D 1ms out16b 768 / (96kHz * 2 * 2) =3D 2ms out24b 576 / (96kHz * 3 * 2) =3D 1ms Out 16 bit mode claims to accept 2ms packets (but still interval 1). I'm wondering if this is just an error in the device reported capability (or ma= ybe it can buffer?). Do isochronous outputs have to use the full max packet siz= e? --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=