From 08f80bb5196517a0dfe50dc7c10f234c0ff2f0e8 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Tue, 17 Jun 2008 18:17:39 +0400 Subject: mmc: change .get_ro() callback semantics Now get_ro() callback must return 0/1 values for its logical states, 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 at91_mci, 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 Signed-off-by: Pierre Ossman 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..b9d4ed6 100644 --- a/drivers/mmc/host/at91_mci.c +++ b/drivers/mmc/host/at91_mci.c @@ -793,19 +793,15 @@ static irqreturn_t at91_mmc_det_irq(int irq, void *_host) static int at91_mci_get_ro(struct mmc_host *mmc) { - int read_only = 0; struct at91mci_host *host = mmc_priv(mmc); - if (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") ); - } - else { - printk(KERN_WARNING "%s: host does not support reading read-only " - "switch. Assuming write-enable.\n", mmc_hostname(mmc)); - } - return read_only; + if (host->board->wp_pin) + return !!gpio_get_value(host->board->wp_pin); + /* + * Board doesn't support read only detection; let the mmc core + * decide what to do. + */ + return -ENOSYS; } static const struct mmc_host_ops at91_mci_ops = { diff --git a/drivers/mmc/host/imxmmc.c b/drivers/mmc/host/imxmmc.c index eed211b..5e880c0 100644 --- a/drivers/mmc/host/imxmmc.c +++ b/drivers/mmc/host/imxmmc.c @@ -892,9 +892,12 @@ 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 547eb85..4e82f64 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 d89475d..d39f597 100644 --- a/drivers/mmc/host/pxamci.c +++ b/drivers/mmc/host/pxamci.c @@ -374,9 +374,12 @@ 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/drivers/mmc/host/wbsd.c b/drivers/mmc/host/wbsd.c index c303e7f..67e5a9b 100644 --- a/drivers/mmc/host/wbsd.c +++ b/drivers/mmc/host/wbsd.c @@ -939,7 +939,7 @@ static int wbsd_get_ro(struct mmc_host *mmc) spin_unlock_bh(&host->lock); - return csr & WBSD_WRPT; + return !!(csr & WBSD_WRPT); } static const struct mmc_host_ops wbsd_ops = { diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 6188e19..753b723 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -58,6 +58,18 @@ struct mmc_host_ops { * * Also note that these functions might sleep, so don't call them * in the atomic contexts! + * + * Return values for the get_ro callback should be: + * 0 for a read/write card + * 1 for a read-only card + * -ENOSYS when not supported (equal to NULL callback) + * or a negative errno value when something bad happened + * + * Return values for the get_ro callback should be: + * 0 for a absent card + * 1 for a present card + * -ENOSYS when not supported (equal to NULL callback) + * or a negative errno value when something bad happened */ void (*set_ios)(struct mmc_host *host, struct mmc_ios *ios); int (*get_ro)(struct mmc_host *host); -- cgit v0.10.2