From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f181.google.com (mail-pg1-f181.google.com [209.85.215.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 92E8E69DF4 for ; Fri, 29 Mar 2024 14:23:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711722237; cv=none; b=OCoOXmmKDLrd9dmIk56e+o4AhJlKuVFIxTOexmAuBDOHEZj+9BWgfne/gHUCXAXt5NG1HPrRoo9/OYw1mOKCiZoh1PCOZbYZ0kkraLZ/o9QGOxo061Q6zDp1+NGj1TDz4Kefs8nFTFQC8dTEdlZHS6ogB7raUMChyWzTQG8C+8c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711722237; c=relaxed/simple; bh=qmdwo0uZTo5Hz0MrRtgqmAITVhPLzO95UNrOrd6I9MY=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=iJGWEPc0FiLOimokmNWblpAon13h5pdIQA+nrnOdnvloLuRp36UE3XNkaBb/GKr69uDAyPpr61OCkCNKjuWkGeLDHsTxOoiJxsR96s6XYkXvNFXHQZiVewAGItE4vIsKE0BY/njqUB7fqP9l5dbU8q1B5WcsLlRBh9zvnjmi+kc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=fastcomproducts.com; spf=fail smtp.mailfrom=fastcomproducts.com; dkim=pass (2048-bit key) header.d=fastcomproducts-com.20230601.gappssmtp.com header.i=@fastcomproducts-com.20230601.gappssmtp.com header.b=A0VbHAoC; arc=none smtp.client-ip=209.85.215.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=fastcomproducts.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=fastcomproducts.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=fastcomproducts-com.20230601.gappssmtp.com header.i=@fastcomproducts-com.20230601.gappssmtp.com header.b="A0VbHAoC" Received: by mail-pg1-f181.google.com with SMTP id 41be03b00d2f7-5d8ddbac4fbso1384433a12.0 for ; Fri, 29 Mar 2024 07:23:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fastcomproducts-com.20230601.gappssmtp.com; s=20230601; t=1711722235; x=1712327035; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=CIC6A0Lm2P1UPx/QiRg3Lr3l/yiPxwSFRW6lPV3c42A=; b=A0VbHAoCBr7ouN0MzwbbaQLZeeaEQxT5qgeJ7K8zg1qTgL8NuMaBSPCE7z7XYJ1IEa QyGKDBNNmQcstKSgPGdNWBHXOtg/9VenjGdvdTRF/L+t8MVMgFggLStV2KYBj8j5hStH W+JHvUYFUOjO8IssPd3mDo1y2w5kLXgwbSSpDFsNF38tE8/FL1xiZnFWGQFEUJOq/SME mYqwetH6LJinq5w4cAOqYeFcY3RJmJKYT+LkcMTJiMpytIqhFjb8q2LgxBvlzZ3hETxd I4uQKN1AO0TMFSpQlYD3MBbf0LPfJvOJgFsUBZNdFLKPeA2T4Z/8R5JPeM/Nh/wLLWF0 +nHw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711722235; x=1712327035; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CIC6A0Lm2P1UPx/QiRg3Lr3l/yiPxwSFRW6lPV3c42A=; b=AoeBXCGWLwllxuCqAlbKnYvSKns/ji6TiT2osPbAwKPGEJWhrCMhx4EVii2Yd2EyPk 1/nIthdC+5fwHPNqNA976PlXW1ZQXFaZHhdoawPdWM6IYUTb9q23inD65vtRl+1Pyw5b CkV43mLbyH044V0HIwkx41Wq8Lj830i+p6R79Z0u4U/3ZSsl7Pyj9WzXm4LGb3rZ3VrO vfCyzaaLzM1NZlICRIMM6Tq8hf1tbjdBp2ZXjicBjVgRcvVY2BIrVLtrMHRqgnbnKWWI VyJPQTJFEdoqLmkKhZCKpUnXIWJZMp//rWZ9aaGdOQEiydBYhsFkcleTIKYdG9Xkp1dn 07dw== X-Gm-Message-State: AOJu0Yx0s7qOWAXoDPggV6r1Gg7KN7Zzy62JBUk+sqGxMKsm3ukm8JnG 86cM8OOeHjQUNKPFocUjXfyI0j/owNJUhT+N+iKwuM5x8hjXGUMJZkgS6+MJl8aRtt00/TGeYiJ ZDWOkSxshalSvJ2+JuidEclgbeLl0rGk3Kw2Fu++jNKgvI9w= X-Google-Smtp-Source: AGHT+IFnNNBFQdypV0Ei1yUypOXiPZMhrRlRPqTwiXaHFJDD5xAV9+Ah/xE+eVeAp4YLIaFX6NXqdwWXUnt2KpzHyiM= X-Received: by 2002:a05:6a20:1582:b0:1a3:4635:6aab with SMTP id h2-20020a056a20158200b001a346356aabmr2452712pzj.62.1711722234964; Fri, 29 Mar 2024 07:23:54 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <2024032920-replay-ruined-d92d@gregkh> In-Reply-To: <2024032920-replay-ruined-d92d@gregkh> From: Joshua Droney Date: Fri, 29 Mar 2024 09:23:49 -0500 Message-ID: Subject: Re: Incorrect UART in /tty/serial/8250 To: Greg KH Cc: linux-serial@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable I would appreciate some guidance on this. I don't know enough about the kernel's serial driver to be confident about what changes need to be made, nor anything about creating/submitting a patch. Thanks! Josh On Fri, Mar 29, 2024 at 1:01=E2=80=AFAM Greg KH wrote: > > On Thu, Mar 28, 2024 at 02:34:10PM -0500, Joshua Droney wrote: > > Hello! > > > > My name is Josh. I'm currently employed at Commtech, Inc. > > (https://fastcomproducts.com/). I'm following the instructions at > > https://kernelnewbies.org/FoundBug to report this issue. Please let me > > know if this is incorrect. > > > > We (Commtech) have several serial boards, but the board in question is > > the '422/2-PCIe'. This board does not exist, but someone added it to > > the Linux kernel at some point in the past. This wouldn't be a > > problem, except that the board ID that was used for this non-existent > > board (0x22) was ultimately used for a different REAL board, with a > > different UART. Instead of a xr172358, we use a 16C950 on the real > > board. But the Linux kernel finds our other board ID, and tries to > > initialize it as an exar chip and fails. I don't know much about the > > kernel, but I believe the lines in question are: > > > > https://github.com/torvalds/linux/blob/master/drivers/tty/serial/8250/8= 250_exar.c#L47 > > https://github.com/torvalds/linux/blob/master/drivers/tty/serial/8250/8= 250_exar.c#L925 > > > > You can see that we have a different board with device ID 0x22 here: > > https://admin.pci-ids.ucw.cz/read/PC/18f7 > > > > The 422/4-PCIe exists (0x20), the 422/8-PCIe exists (0x21), but the > > 422/2-PCIe was never created and its device id was used for a > > different board (0x22, the SuperFSCC/4-LVDS-PCIe). > > Can you please submit a patch that fixes this? We'll be glad to take > it. If you need help making it, please let us know. > > thanks, > > greg k-h