From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartlomiej Zolnierkiewicz Subject: Re: [PATCH 2/5] pata_sis: Implement MWDMA for the UDMA 133 capable chips Date: Tue, 17 Nov 2009 18:57:01 +0100 Message-ID: <200911171857.01805.bzolnier@gmail.com> References: <20091117144450.15430.83450.stgit@localhost.localdomain> <200911171827.29891.bzolnier@gmail.com> <20091117173823.217b95a7@lxorguk.ukuu.org.uk> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-fx0-f221.google.com ([209.85.220.221]:40257 "EHLO mail-fx0-f221.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753706AbZKQR6L (ORCPT ); Tue, 17 Nov 2009 12:58:11 -0500 In-Reply-To: <20091117173823.217b95a7@lxorguk.ukuu.org.uk> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: Alan Cox , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org On Tuesday 17 November 2009 18:38:23 Alan Cox wrote: > > > +static int mwdma_clip_to_pio(struct ata_device *adev) > > > +{ > > > + const int mwdma_to_pio[3] = { > > > + XFER_PIO_0, XFER_PIO_3, XFER_PIO_4 > > > + }; > > > + return min(mwdma_to_pio[adev->dma_mode - XFER_MW_DMA_0], > > > + adev->pio_mode - XFER_PIO_0); > > > +} > > > > This wants to be in the generic libata code. > > I'm not convinced because for the majority of drivers the libata timing > interface handles it. SiS needs it just because it does things by > precomputed tables. It's a one off interface. Controllers based on *Intel* PIIX are in the disagreement with the above paragraph and having generic helper to do conversion (without a clipping) would bring us a little step closer to killing a needless code duplication currently present in their ->set_piomode and ->set_dmamode methods. [ In case somebody wonders: no, 'old' drivers don't have such duplication and 'whoever did it didn't port it across' cause said 'whoever'-s were not into the development of the square wheels.... ] -- Bartlomiej Zolnierkiewicz