From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: PATA drivers in libata? Date: Thu, 17 Feb 2005 12:11:48 +1100 Message-ID: <1108602708.5382.9.camel@gaston> References: <420FA1B9.6030100@pobox.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Received: from gate.crashing.org ([63.228.1.57]:3229 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S262067AbVBQBMP (ORCPT ); Wed, 16 Feb 2005 20:12:15 -0500 In-Reply-To: <420FA1B9.6030100@pobox.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Bartlomiej Zolnierkiewicz , "linux-ide@vger.kernel.org" , Alan Cox , Albert Lee On Sun, 2005-02-13 at 13:51 -0500, Jeff Garzik wrote: > I wanted to open a discussion on libata and PATA. > > libata-dev now has two drivers that support PATA, pata_pdc2027x and > ata_piix, and the core is getting close (DMA blacklist in, C/H/S support > close). > > What are the opinions on issues relating to making PATA libata support > available in the upstream kernel? Here's my random list. > > * I think CONFIG_IDE should continue to be the default answer for "what > driver do I use for PATA?" Yes. > * Should there be a config option similar to CONFIG_BLK_DEV_IDE_SATA, > called CONFIG_SCSI_ATA_PATA? A runtime 'pata' module option? Should we > include 'DANGER DANGER conflicts with CONFIG_IDE' in the Kconfig > description? Eventually... I'm thinking I may port the "macio" IDE to libata one day, but for now, I still need both drivers/ide for it and libata for SATA. > * With ATA passthru (in libata-dev currently), libata supports SMART and > the HDIO_CMD/HDIO_TASK generalized ioctls. Should I care about > supporting other ioctls? > > * pci_enable_device() issues? > > * power management differences? Well, libata doesn't have power management proper at all for now. In fact, I need to do something at the generic SCSI level similar to what I did for drivers/ide, that is turning the PM callbacks into requests down the queues etc... but I don't have any SCSI or libata HW that can power manage at the moment, so I didn't quite bother yet. (Though if I ported "macio" IDE ... ) Ultimately, it will have to be done for things like USB & firewire too anyway. So maybe I should start working on this soonish. I talked a bit with jejb at OLS a year or 2 ago about the way to do it, it shouldn't be that much different than what I do in drivers/ide, but then, I know pretty much nothing about the linux scsi layer... Ben.