[PATCH v2 3/3] sdhci-s3c: Add SDHCI_QUIRK_NO_WP_BIT quirk

[Kukjin Kim]

From: Hyuk Lee <hyuk1.lee at samsung.com>

If host controller doesn't have WP pin which should be connnected with SDMMC
card WP pin, can implement get_ro function with using the allocated gpio.
In order to use this quirk wp_gpio in the platform data must be set.

Signed-off-by: Hyuk Lee <hyuk1.lee at samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim at samsung.com>
---
 drivers/mmc/host/sdhci-s3c.c |   44 ++++++++++++++++++++++++++++++++++++++++++
 drivers/mmc/host/sdhci.c     |    3 ++
 drivers/mmc/host/sdhci.h     |    3 ++
 3 files changed, 50 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
index af21792..ed9376d 100644
--- a/drivers/mmc/host/sdhci-s3c.c
+++ b/drivers/mmc/host/sdhci-s3c.c
@@ -18,11 +18,13 @@
 #include <linux/slab.h>
 #include <linux/clk.h>
 #include <linux/io.h>
+#include <linux/gpio.h>
 
 #include <linux/mmc/host.h>
 
 #include <plat/sdhci.h>
 #include <plat/regs-sdhci.h>
+#include <plat/gpio-cfg.h>
 
 #include "sdhci.h"
 
@@ -209,6 +211,36 @@ static void sdhci_s3c_set_clock(struct sdhci_host *host, unsigned int clock)
 	}
 }
 
+/**
+ * sdhci_s3c_get_ro - callback for get_ro
+ * @host: The SDHCI host being changed
+ *
+ * If the WP pin is connected with GPIO, can get the value which indicates
+ * the card is locked or not.
+*/
+static int sdhci_s3c_get_ro(struct mmc_host *mmc)
+{
+	struct sdhci_s3c *sc;
+	struct sdhci_host *host;
+
+	host = mmc_priv(mmc);
+	sc = sdhci_priv(host);
+
+	return gpio_get_value(sc->pdata->wp_gpio);
+}
+
+/**
+ * sdhci_s3c_cfg_wp - configure GPIO for WP pin
+ * @gpio_num: GPIO number which connected with WP line from SD/MMC slot
+ *
+ * Configure GPIO for using WP line
+*/
+static void sdhci_s3c_cfg_wp(unsigned int gpio_num)
+{
+	s3c_gpio_cfgpin(gpio_num, S3C_GPIO_INPUT);
+	s3c_gpio_setpull(gpio_num, S3C_GPIO_PULL_UP);
+}
+
 static struct sdhci_ops sdhci_s3c_ops = {
 	.get_max_clock		= sdhci_s3c_get_max_clk,
 	.get_timeout_clock	= sdhci_s3c_get_timeout_clk,
@@ -311,6 +343,9 @@ static int __devinit sdhci_s3c_probe(struct platform_device *pdev)
 	if (pdata->cfg_gpio)
 		pdata->cfg_gpio(pdev, pdata->max_width);
 
+	if (pdata->wp_gpio)
+		sdhci_s3c_ops.get_ro = sdhci_s3c_get_ro;
+
 	host->hw_name = "samsung-hsmmc";
 	host->ops = &sdhci_s3c_ops;
 	host->quirks = 0;
@@ -335,6 +370,15 @@ static int __devinit sdhci_s3c_probe(struct platform_device *pdev)
 	host->quirks |= (SDHCI_QUIRK_32BIT_DMA_ADDR |
 			 SDHCI_QUIRK_32BIT_DMA_SIZE);
 
+	/* Controller's WP pin donsn't connected with SD card. So we allocate
+	 * a GPIO for getting WP data from SD card and use that data as
+	 * the return value of the get_ro function */
+	host->quirks |= SDHCI_QUIRK_NO_WP_BIT;
+
+	/* to configure gpio pin as a card write protection signal */
+	if (pdata->wp_gpio)
+		sdhci_s3c_cfg_wp(pdata->wp_gpio);
+
 	ret = sdhci_add_host(host);
 	if (ret) {
 		dev_err(dev, "sdhci_add_host() failed\n");
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index c6d1bd8..2f8dfbc 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1192,6 +1192,9 @@ static int sdhci_get_ro(struct mmc_host *mmc)
 
 	host = mmc_priv(mmc);
 
+	if ((host->quirks & SDHCI_QUIRK_NO_WP_BIT) && host->ops->get_ro)
+		return host->ops->get_ro(mmc);
+
 	spin_lock_irqsave(&host->lock, flags);
 
 	if (host->flags & SDHCI_DEVICE_DEAD)
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index c846813..f479e22 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -240,6 +240,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN		(1<<25)
 /* Controller cannot support End Attribute in NOP ADMA descriptor */
 #define SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC		(1<<26)
+/* Controller has no write-protect pin connected with SD card */
+#define SDHCI_QUIRK_NO_WP_BIT                          (1<<27)
 
 	int			irq;		/* Device IRQ */
 	void __iomem *		ioaddr;		/* Mapped address */
@@ -312,6 +314,7 @@ struct sdhci_ops {
 	unsigned int	(*get_max_clock)(struct sdhci_host *host);
 	unsigned int	(*get_min_clock)(struct sdhci_host *host);
 	unsigned int	(*get_timeout_clock)(struct sdhci_host *host);
+	int		(*get_ro)(struct mmc_host *mmc);
 };
 
 #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
-- 
1.6.2.5