[PATCH 1/3] SDHCI: add sdhci_get_cd callback to detect the card

[<Chang-Ming.Huang@freescale.com>]

From: Jerry Huang <Chang-Ming.Huang@freescale.com>

Add callback function sdhci_get_cd to detect the card.

In order to check if the card is present,
we will read the PRESENT STATE register and check the bit15.

Signed-off-by: Jerry Huang <Chang-Ming.Huang@freescale.com>
---
 drivers/mmc/host/sdhci.c |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 9e15f41..2e60372 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1262,6 +1262,24 @@ static int sdhci_get_ro(struct mmc_host *mmc)
 		!is_readonly : is_readonly;
 }
 
+static int sdhci_get_cd(struct mmc_host *mmc)
+{
+	struct sdhci_host *host = mmc_priv(mmc);
+	unsigned long flags;
+	int present;
+
+	spin_lock_irqsave(&host->lock, flags);
+
+	if (host->flags & SDHCI_DEVICE_DEAD)
+		present = 0;
+	else
+		present = sdhci_readl(host, SDHCI_PRESENT_STATE);
+
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	return present & SDHCI_CARD_PRESENT;
+}
+
 static void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable)
 {
 	struct sdhci_host *host;
@@ -1288,6 +1306,7 @@ static const struct mmc_host_ops sdhci_ops = {
 	.request	= sdhci_request,
 	.set_ios	= sdhci_set_ios,
 	.get_ro		= sdhci_get_ro,
+	.get_cd		= sdhci_get_cd,
 	.enable_sdio_irq = sdhci_enable_sdio_irq,
 };
 
-- 
1.7.4.1