mmc: sdhci: refine non-removable card checking for card detection

commit 87b87a3fc0eec58d95e4216392f889a26439ad22 upstream.

Commit c79396c191bc19 ("mmc: sdhci: prevent card detection activity
for non-removable cards") disables card detection where the cards
are marked as non-removable.

This makes sense, but the implementation detail of calling
mmc_card_is_removable() causes some problems, because
mmc_card_is_removable() is overloaded with CONFIG_MMC_UNSAFE_RESUME
semantics.

In the OLPC XO case, we need CONFIG_MMC_UNSAFE_RESUME because our root
filesystem is stored on SD, but we also have external SD card slots
where we want automatic card detection.

Refine the check to only apply to hosts marked as MMC_CAP_NONREMOVABLE,
which is defined to mean that the card is *really* nonremovable. This
could be revisited in future if we find a way to improve
CONFIG_MMC_UNSAFE_RESUME semantics.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Acked-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 8d66706824a6105ceeac2f63526372a4f0c521fd..5789e097d93c76f71ee02e86baaa8da61086974e 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -147,7 +147,7 @@ static void sdhci_set_card_detection(struct sdhci_host *host, bool enable)
        u32 present, irqs;
 
        if ((host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) ||
-           !mmc_card_is_removable(host->mmc))
+           (host->mmc->caps & MMC_CAP_NONREMOVABLE))
                return;
 
        present = sdhci_readl(host, SDHCI_PRESENT_STATE) &