Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755065Ab1CAOIC (ORCPT ); Tue, 1 Mar 2011 09:08:02 -0500 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:35316 "EHLO www.etchedpixels.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754619Ab1CAOIB (ORCPT ); Tue, 1 Mar 2011 09:08:01 -0500 Date: Tue, 1 Mar 2011 14:07:43 +0000 From: Alan Cox To: "Subhasish Ghosh" Cc: , , , , , "Greg Kroah-Hartman" , "open list" , "Stalin Srinivasan" Subject: Re: [PATCH v2 13/13] tty: pruss SUART driver Message-ID: <20110301140743.0b9cf140@lxorguk.ukuu.org.uk> In-Reply-To: <99CE1730AA2F4F2F91AFA71BD75FDC41@subhasishg> References: <1297435892-28278-1-git-send-email-subhasish@mistralsolutions.com> <1297435892-28278-14-git-send-email-subhasish@mistralsolutions.com> <20110211162814.6ff274f1@lxorguk.ukuu.org.uk> <20110222111103.5d0dd0a7@lxorguk.ukuu.org.uk> <99CE1730AA2F4F2F91AFA71BD75FDC41@subhasishg> X-Mailer: Claws Mail 3.7.8 (GTK+ 2.22.0; x86_64-redhat-linux-gnu) Face: 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 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 988 Lines: 27 > I tried using a tasklet for the TX part, but that did not help. > Another way is to prepare the buffer for the next read and read the data > immediately. > Something like this: > > 1. Call tty_prepare_flip_string while startup. > 2. When the read interrupt arrives, read the data immediately. > 3. Call tty_prepare_flip_string for the next read. Only you then don't know the size of space required/ > Again, the problem here is that we need to use global variables to store the > pre-allocated buffers You don't. You can store them per port in the existing objects ! > The best way is if we can keep the current implementation, one extra copy is > not hurting us > as we do it after the read_data API. No problem with that at all. -- 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/