From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759172AbYEWPoe (ORCPT ); Fri, 23 May 2008 11:44:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757659AbYEWPnt (ORCPT ); Fri, 23 May 2008 11:43:49 -0400 Received: from rtsoft3.corbina.net ([85.21.88.6]:2533 "EHLO buildserver.ru.mvista.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1756804AbYEWPns (ORCPT ); Fri, 23 May 2008 11:43:48 -0400 Date: Fri, 23 May 2008 19:43:47 +0400 From: Anton Vorontsov To: Kumar Gala , David Brownell , Pierre Ossman Cc: Jochen Friedrich , Timur Tabi , linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, spi-devel-general@lists.sourceforge.net Subject: [PATCH 3/3] mmc: change .get_ro() callback semantics Message-ID: <20080523154347.GC24862@polina.dev.rtsoft.ru> References: <20080523154204.GA19803@polina.dev.rtsoft.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Disposition: inline In-Reply-To: <20080523154204.GA19803@polina.dev.rtsoft.ru> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org get_ro() callback must return values >= 0 for its logical state, and negative errno values in case of error. If particular host instance doesn't support RO/WP switch, it should return -ENOSYS. This patch changes some hosts in two ways: 1. Now functions should be smart to not return negative values in "RO asserted" case (particularly gpio_ calls could return negative values for the outermost GPIOs). Also, board code usually passes get_ro() callbacks that directly return gpioreg & bit result, so imxmmc, pxamci and mmc_spi's get_ro() handlers need take special care when returning platform's values to the mmc core. 2. In case of host instance didn't implement get_ro() callback, it should really return -ENOSYS and let the mmc core decide what to do about it (mmc core thinks the same way as the hosts, so it isn't functional change). Signed-off-by: Anton Vorontsov --- drivers/mmc/core/sd.c | 4 ++-- drivers/mmc/host/at91_mci.c | 2 +- drivers/mmc/host/imxmmc.c | 9 ++++++--- drivers/mmc/host/mmc_spi.c | 9 ++++++--- drivers/mmc/host/pxamci.c | 9 ++++++--- include/linux/mmc/host.h | 3 +++ 6 files changed, 24 insertions(+), 12 deletions(-) diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index 7ef3b15..b122eb9 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -494,13 +494,13 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr, * Check if read-only switch is active. */ if (!oldcard) { - if (!host->ops->get_ro) { + if (!host->ops->get_ro || host->ops->get_ro(host) < 0) { printk(KERN_WARNING "%s: host does not " "support reading read-only " "switch. assuming write-enable.\n", mmc_hostname(host)); } else { - if (host->ops->get_ro(host)) + if (host->ops->get_ro(host) > 0) mmc_card_set_readonly(card); } } diff --git a/drivers/mmc/host/at91_mci.c b/drivers/mmc/host/at91_mci.c index 8979ad3..140c2b8 100644 --- a/drivers/mmc/host/at91_mci.c +++ b/drivers/mmc/host/at91_mci.c @@ -797,7 +797,7 @@ static int at91_mci_get_ro(struct mmc_host *mmc) struct at91mci_host *host = mmc_priv(mmc); if (host->board->wp_pin) { - read_only = gpio_get_value(host->board->wp_pin); + read_only = !!gpio_get_value(host->board->wp_pin); printk(KERN_WARNING "%s: card is %s\n", mmc_hostname(mmc), (read_only ? "read-only" : "read-write") ); } diff --git a/drivers/mmc/host/imxmmc.c b/drivers/mmc/host/imxmmc.c index 95f33e8..5167679 100644 --- a/drivers/mmc/host/imxmmc.c +++ b/drivers/mmc/host/imxmmc.c @@ -889,9 +889,12 @@ static int imxmci_get_ro(struct mmc_host *mmc) struct imxmci_host *host = mmc_priv(mmc); if (host->pdata && host->pdata->get_ro) - return host->pdata->get_ro(mmc_dev(mmc)); - /* Host doesn't support read only detection so assume writeable */ - return 0; + return !!host->pdata->get_ro(mmc_dev(mmc)); + /* + * Board doesn't support read only detection; let the mmc core + * decide what to do. + */ + return -ENOSYS; } diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index 724870c..85d9853 100644 --- a/drivers/mmc/host/mmc_spi.c +++ b/drivers/mmc/host/mmc_spi.c @@ -1126,9 +1126,12 @@ static int mmc_spi_get_ro(struct mmc_host *mmc) struct mmc_spi_host *host = mmc_priv(mmc); if (host->pdata && host->pdata->get_ro) - return host->pdata->get_ro(mmc->parent); - /* board doesn't support read only detection; assume writeable */ - return 0; + return !!host->pdata->get_ro(mmc->parent); + /* + * Board doesn't support read only detection; let the mmc core + * decide what to do. + */ + return -ENOSYS; } static int mmc_spi_get_cd(struct mmc_host *mmc) diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c index 65210fc..b6056bd 100644 --- a/drivers/mmc/host/pxamci.c +++ b/drivers/mmc/host/pxamci.c @@ -361,9 +361,12 @@ static int pxamci_get_ro(struct mmc_host *mmc) struct pxamci_host *host = mmc_priv(mmc); if (host->pdata && host->pdata->get_ro) - return host->pdata->get_ro(mmc_dev(mmc)); - /* Host doesn't support read only detection so assume writeable */ - return 0; + return !!host->pdata->get_ro(mmc_dev(mmc)); + /* + * Board doesn't support read only detection; let the mmc core + * decide what to do. + */ + return -ENOSYS; } static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index f2e9885..ef3b773 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -55,6 +55,9 @@ struct mmc_host_ops { * Avoid calling these three functions too often or in a "fast path", * since underlaying controller might implement them in an expensive * and/or slow way. + * + * .get_ro and .get_cd should return >= 0 for their logical values, + * or negative errno value in case of error. */ void (*set_ios)(struct mmc_host *host, struct mmc_ios *ios); int (*get_ro)(struct mmc_host *host); -- 1.5.5.1