Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752590Ab2HMNd2 (ORCPT ); Mon, 13 Aug 2012 09:33:28 -0400 Received: from mail-vc0-f174.google.com ([209.85.220.174]:41421 "EHLO mail-vc0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752394Ab2HMNdZ (ORCPT ); Mon, 13 Aug 2012 09:33:25 -0400 MIME-Version: 1.0 In-Reply-To: <20120809123855.1ba0fffb@pyramind.ukuu.org.uk> References: <1344322471-3640-1-git-send-email-arun.murthy@stericsson.com> <1344322471-3640-2-git-send-email-arun.murthy@stericsson.com> <20120807183809.GC26990@kroah.com> <20120808133748.GA14459@kroah.com> <20120809123855.1ba0fffb@pyramind.ukuu.org.uk> Date: Mon, 13 Aug 2012 15:33:24 +0200 Message-ID: Subject: Re: [PATCHv2 1/4] modem_shm: Add Modem Access Framework From: Linus Walleij To: Alan Cox , Greg KH Cc: Arun MURTHY , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-doc@vger.kernel.org" , Sjur BRENDELAND Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1594 Lines: 35 On Thu, Aug 9, 2012 at 1:38 PM, Alan Cox wrote: >> Maybe tty can do this, but want to have all modem related separately. >> There are many such hardware and many drivers coming up in near future. > > tty can't do all this. We have similar things with stuff like CAIF. Modem > has gone from pretending to be a serial port (tty) to appearing as a > smart multi-function controller. I second this, I plead guilty to suggesting to use "modem_shm" as a layer below because things like CAIF and Phonet are just growing and growing. Sure, many of them can emulate AT commands, but that is not their native tongue, and increasingly any AT command parser is constrained to userspace which in turn constructs the actually intended IPC command sequency for doing ATDT555784629568. These modems are not talking anything resembling a line discipline, they have their own binary protocol and above are protocols like CAIF and Phonet talking to the modem, including IPC to processes running on the other sides, with states. Sjur is currently working on a future platform where we'll attempt to bring things closer to existing Linux frameworks using virtio rings and rpmesg also on the modem side, but the modems Arun are working on are already deployed with this type of firmware talking some other IPC lingo. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/