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 0F2553E49B for ; Fri, 29 Mar 2024 06:01:34 +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=1711692095; cv=none; b=dcT4Gb0lVqlkQKkhyrOny6s6J7d5D7yYaJNAbjFAeS4LIYaF4JtB+/1dlCtpnJunTnzpdgv1mnFpdjS41wdoNVFbValO4uBe6CFlUcxKlYUzgNSlmE9REp6QIBFATx/vZQVn0oGP7XFgdQDdrct9XiqfkatWDN6xoN6Yet1abos= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711692095; c=relaxed/simple; bh=4wkIc6pW5/DDOEkX8KSUtoZD31gZIPyUO6EbPQjma+Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=nEm8I8VW+v62BGrSKd0K+WGsU892knicCoipfq2jjJquONYoVwrd5+Pb69GshYYuR2s/R1j77g96d/Y1MCxkchymABGEzmH4KXpxGDXDkMmEB4QaySKq5XOc2U/YzHb2zSB9RnGtY+AdqIRJ1QX00ZgM5ZJX7MI0WdP8Cx9szGY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=drdV3qJ3; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="drdV3qJ3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A35FC433C7; Fri, 29 Mar 2024 06:01:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1711692094; bh=4wkIc6pW5/DDOEkX8KSUtoZD31gZIPyUO6EbPQjma+Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=drdV3qJ3In8efU70UQkQOUNy+H88B5cQQZeDFau4mlu7AibZTKtzzwJgztx1EMc6A KrxTlvHBiBAAKtcS0XtW59+rgWs16yl5MCLlSRy4qwyargYdlAfJ+1iUvBSvQp63jI pAB44mf6IrPHbvSLGiFyQx/JgWqJx10FtIvC4irY= Date: Fri, 29 Mar 2024 07:01:31 +0100 From: Greg KH To: Joshua Droney Cc: linux-serial@vger.kernel.org Subject: Re: Incorrect UART in /tty/serial/8250 Message-ID: <2024032920-replay-ruined-d92d@gregkh> References: Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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/8250/8250_exar.c#L47 > https://github.com/torvalds/linux/blob/master/drivers/tty/serial/8250/8250_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