[PATCH v5 3/3] sdhci-s3c: Add SDHCI_QUIRK_NO_WP_BIT quirk for Samsung SoC

[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>
Cc: Ben Dooks <ben-linux at fluff.org>
---
Changes since v4:
- Address comments from Marek.

Hi Andrew,
If there are no problems, could you please apply this patch?

 drivers/mmc/host/sdhci-s3c.c |   36 ++++++++++++++++++++++++++++++++++++
 drivers/mmc/host/sdhci.c     |    3 +++
 drivers/mmc/host/sdhci.h     |    3 +++
 3 files changed, 42 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
index 0d25285..98a8ec8 100644
--- a/drivers/mmc/host/sdhci-s3c.c
+++ b/drivers/mmc/host/sdhci-s3c.c
@@ -22,6 +22,7 @@
 
 #include <linux/mmc/host.h>
 
+#include <plat/gpio-cfg.h>
 #include <plat/sdhci.h>
 #include <plat/regs-sdhci.h>
 
@@ -213,6 +214,32 @@ 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 *ourhost = to_s3c(mmc_priv(mmc));
+
+	return gpio_get_value(ourhost->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);
+}
+
+/**
  * sdhci_s3c_get_min_clock - callback to get minimal supported clock value
  * @host: The SDHCI host being queried
  *
@@ -408,6 +435,15 @@ 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 doesn't connected with SD card and there is an
+	 * allocated GPIO for getting WP data form SD card, use this quirk and
+	 * send the GPIO number in pdata->wp_gpio. */
+	if (pdata->has_wp_gpio && gpio_is_valid(pdata->wp_gpio)) {
+		sdhci_s3c_ops.get_ro = sdhci_s3c_get_ro;
+		host->quirks |= SDHCI_QUIRK_NO_WP_BIT;
+		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 f9ca4c6..7fba401 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1198,6 +1198,9 @@ 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 0de8b38..dd9a233 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -247,6 +247,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK_MISSING_CAPS			(1<<28)
 /* Controller has nonstandard clock management */
 #define SDHCI_QUIRK_NONSTANDARD_MINCLOCK		(1<<29)
+/* Controller has no write-protect pin connected with SD card */
+#define SDHCI_QUIRK_NO_WP_BIT				(1<<30)
 
 	int			irq;		/* Device IRQ */
 	void __iomem *		ioaddr;		/* Mapped address */
@@ -321,6 +323,7 @@ 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