Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752038AbZGYPyC (ORCPT ); Sat, 25 Jul 2009 11:54:02 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751958AbZGYPyB (ORCPT ); Sat, 25 Jul 2009 11:54:01 -0400 Received: from cs20.apochromatic.org ([204.152.189.161]:52973 "EHLO cs20.apochromatic.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751952AbZGYPyA (ORCPT ); Sat, 25 Jul 2009 11:54:00 -0400 Date: Sat, 25 Jul 2009 16:53:36 +0100 From: Matt Fleming To: Adrian Hunter Cc: Pierre Ossman , Jarkko Lavinen , Denis Karpov , linux-omap Mailing List , lkml , Andrew Morton Subject: Re: [PATCH 7/32] mmc: add host capabilities for SD only and MMC only Message-ID: <20090725155336.GA12665@console-pimps.org> References: <20090710124004.1262.10422.sendpatchset@ahunter-tower> <20090710124054.1262.18902.sendpatchset@ahunter-tower> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090710124054.1262.18902.sendpatchset@ahunter-tower> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2116 Lines: 51 On Fri, Jul 10, 2009 at 03:40:54PM +0300, Adrian Hunter wrote: > > Some hosts can accept only certain types of cards. > For example, an eMMC is MMC only and a uSD slot may > be SD only. However the MMC card scanning logic > checks for all card types one by one. > > Add host capabilities to specify which card types > cannot be used, and amend the card scanning logic > to skip scanning for those types. > I'm only nitpicking here, but I think that logic is a little inverted. By saying which cards cannot be used (as opposed to which cards can be used), we get conditionals like this, > > - mmc_send_if_cond(host, host->ocr_avail); > + if (!(host->caps & MMC_CAP_NOT_SDIO) || !(host->caps & MMC_CAP_NOT_SD)) > + mmc_send_if_cond(host, host->ocr_avail); > + Whilst reviewing this patch it took my brain a few too many seconds to parse that as "if the host is capable of SDIO or SD". > diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h > index 0a60b02..e996967 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -150,6 +150,13 @@ struct mmc_host { > #define MMC_CAP_DISABLE (1 << 7) /* Can the host be disabled */ > #define MMC_CAP_NONREMOVABLE (1 << 8) /* Nonremovable e.g. eMMC */ > #define MMC_CAP_WAIT_WHILE_BUSY (1 << 9) /* Waits while card is busy */ > +#define MMC_CAP_NOT_SDIO (1 << 10) /* Card cannot be SDIO */ > +#define MMC_CAP_NOT_SD (1 << 11) /* Card cannot be SD */ > +#define MMC_CAP_NOT_MMC (1 << 12) /* Card cannot be MMC */ > + > +#define MMC_CAP_SDIO_ONLY (MMC_CAP_NOT_SD | MMC_CAP_NOT_MMC) > +#define MMC_CAP_SD_ONLY (MMC_CAP_NOT_SDIO | MMC_CAP_NOT_MMC) > +#define MMC_CAP_MMC_ONLY (MMC_CAP_NOT_SDIO | MMC_CAP_NOT_SD) > And by saying what capabilities a host supports, when we add new capabilities we don't have to modify existing code to say that it doesn't support the new capability. -- 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/