sdhci-tegra:Enable Hotplugin and wp support for sd card.

Enabling hot plugin/plugout support for sd card using
a gpio.
Enabling write protect detection support for sd card
using a gpio.
Enabling SDHCI_QUIRK_BROKEN_CARD_DETECTION quirk for
sdmmc on T30.

Bug 784133
Bug 786261

Original-Change-Id: Ie9a49472f4b2337a7e2b0eb52c2cb346b021f768
Reviewed-on: http://git-master/r/18438
Tested-by: Pavan Kunapuli <pkunapuli@nvidia.com>
Reviewed-by: Venkata Nageswara Penumarty <vpenumarty@nvidia.com>
Reviewed-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Scott Williams <scwilliams@nvidia.com>
Change-Id: I5b41730281aa360b2ec29fd94c7644d008e8be28

3 files changed, 66 insertions, 11 deletions

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index 90d8d023e0eb..a2a0617f7484 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -62,19 +62,35 @@ struct tegra_sdhci_host {
 	int clk_enabled;
 	bool card_always_on;
 	u32 sdhci_ints;
+	int cd_gpio;
+	int cd_gpio_polarity;
+	int wp_gpio;
+	int wp_gpio_polarity;
 	unsigned int tap_delay;
 	unsigned int max_clk;
 	struct regulator *vsd;
+	unsigned int card_present;
 };
 
 static irqreturn_t carddetect_irq(int irq, void *data)
 {
 	struct sdhci_host *sdhost = (struct sdhci_host *)data;
+	struct tegra_sdhci_host *host = sdhci_priv(sdhost);
+
+	host->card_present =
+		(gpio_get_value(host->cd_gpio) == host->cd_gpio_polarity);
 
 	tasklet_schedule(&sdhost->card_tasklet);
 	return IRQ_HANDLED;
 };
 
+static int tegra_sdhci_card_detect(struct sdhci_host *sdhci)
+{
+	struct tegra_sdhci_host *host = sdhci_priv(sdhci);
+
+	return host->card_present;
+}
+
 static void tegra_sdhci_status_notify_cb(int card_present, void *dev_id)
 {
 	struct sdhci_host *sdhci = (struct sdhci_host *)dev_id;
@@ -191,10 +207,19 @@ static void tegra_sdhci_set_signalling_voltage(struct sdhci_host *sdhci,
 	}
 }
 
+static int tegra_sdhci_get_ro(struct sdhci_host *sdhci)
+{
+	struct tegra_sdhci_host *host = sdhci_priv(sdhci);
+
+	BUG_ON(host->wp_gpio == -1);
+	return (gpio_get_value(host->wp_gpio) == host->wp_gpio_polarity);
+}
+
 static struct sdhci_ops tegra_sdhci_ops = {
 	.enable_dma = tegra_sdhci_enable_dma,
 	.set_clock = tegra_sdhci_set_clock,
 	.configure_capabilities = tegra_sdhci_configure_capabilities,
+	.get_cd = tegra_sdhci_card_detect,
 };
 
 static int __devinit tegra_sdhci_probe(struct platform_device *pdev)
@@ -236,6 +261,10 @@ static int __devinit tegra_sdhci_probe(struct platform_device *pdev)
 	host->card_always_on = (plat->power_gpio == -1) ? 1 : 0;
 	host->max_clk = plat->max_clk;
 	host->tap_delay = plat->tap_delay;
+	host->cd_gpio = plat->cd_gpio;
+	host->cd_gpio_polarity = plat->cd_gpio_polarity;
+	host->wp_gpio = plat->wp_gpio;
+	host->wp_gpio_polarity = plat->wp_gpio_polarity;
 
 	host->clk = clk_get(&pdev->dev, plat->clk_id);
 	if (IS_ERR(host->clk)) {
@@ -314,6 +343,9 @@ static int __devinit tegra_sdhci_probe(struct platform_device *pdev)
 			SDHCI_QUIRK_8_BIT_DATA |
 			SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
 			SDHCI_QUIRK_RUNTIME_DISABLE;
+#ifdef CONFIG_ARCH_TEGRA_3x_SOC
+	sdhci->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
+#endif
 
 	if (plat->force_hs != 0)
 		sdhci->quirks |= SDHCI_QUIRK_FORCE_HIGH_SPEED_MODE;
@@ -325,25 +357,36 @@ static int __devinit tegra_sdhci_probe(struct platform_device *pdev)
 			plat->num_funcs);
 #endif
 
-
-	rc = sdhci_add_host(sdhci);
-	if (rc)
-		goto err_clk_disable;
-
 	platform_set_drvdata(pdev, host);
 
+	/*
+	 * If the card detect gpio is not present, treat the card as
+	 * non-removable.
+	 */
+	if (plat->cd_gpio == -1)
+		host->card_present = 1;
+
 	if (plat->cd_gpio != -1) {
 		rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
 			IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 			mmc_hostname(sdhci->mmc), sdhci);
-
 		if (rc)
 			goto err_remove_host;
+
+		host->card_present =
+			(gpio_get_value(plat->cd_gpio) == host->cd_gpio_polarity);
 	} else if (plat->register_status_notify) {
 		plat->register_status_notify(
 			tegra_sdhci_status_notify_cb, sdhci);
 	}
 
+	if (plat->wp_gpio != -1)
+		tegra_sdhci_ops.get_ro = tegra_sdhci_get_ro;
+
+	rc = sdhci_add_host(sdhci);
+	if (rc)
+		goto err_clk_disable;
+
 	if (plat->board_probe)
 		plat->board_probe(pdev->id, sdhci->mmc);
 
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 153866bc8e0e..d01ca11291d0 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1141,10 +1141,14 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
 
 	host->mrq = mrq;
 
-	/* If polling, assume that the card is always present. */
-	if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
-		present = true;
-	else
+	if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) {
+		if (host->ops->get_cd)
+			present = host->ops->get_cd(host);
+		else {
+			/* If polling, assume that card is always present. */
+			present = true;
+		}
+	} else
 		present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
 				SDHCI_CARD_PRESENT;
 
@@ -1416,10 +1420,17 @@ static const struct mmc_host_ops sdhci_ops = {
 void sdhci_card_detect_callback(struct sdhci_host *host)
 {
 	unsigned long flags;
+	int present;
 
 	spin_lock_irqsave(&host->lock, flags);
 
-	if (!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT)) {
+	if ((host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) && host->ops->get_cd)
+		present = host->ops->get_cd(host);
+	else
+		present = (sdhci_readl(host, SDHCI_PRESENT_STATE) &
+			SDHCI_CARD_PRESENT);
+
+	if (!present) {
 		if (host->mrq) {
 			printk(KERN_ERR "%s: Card removed during transfer!\n",
 				mmc_hostname(host->mmc));
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 9dfa40cf393c..2626f21a6514 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -358,6 +358,7 @@ struct sdhci_ops {
 		unsigned int signalling_voltage);
 
 	int		(*enable_dma)(struct sdhci_host *host);
+	int		(*get_cd)(struct sdhci_host *host);
 	int		(*get_ro)(struct sdhci_host *host);
 	unsigned int	(*get_max_clock)(struct sdhci_host *host);
 	unsigned int	(*get_min_clock)(struct sdhci_host *host);