mmc: sdhci: support runtime PM for BYT SD cards

index 2ea429c..c81c2a2 100644
@@ -58,6 +58,8 @@ static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable);
 #ifdef CONFIG_PM_RUNTIME
 static int sdhci_runtime_pm_get(struct sdhci_host *host);
 static int sdhci_runtime_pm_put(struct sdhci_host *host);
+static void sdhci_runtime_pm_bus_on(struct sdhci_host *host);
+static void sdhci_runtime_pm_bus_off(struct sdhci_host *host);
 #else
 static inline int sdhci_runtime_pm_get(struct sdhci_host *host)
 {

@@ -67,6 +69,12 @@ static inline int sdhci_runtime_pm_put(struct sdhci_host *host)
 {
 	return 0;
 }
+static void sdhci_runtime_pm_bus_on(struct sdhci_host *host)
+{
+}
+static void sdhci_runtime_pm_bus_off(struct sdhci_host *host)
+{
+}
 #endif
 
 static void sdhci_dumpregs(struct sdhci_host *host)

@@ -192,8 +200,12 @@ static void sdhci_reset(struct sdhci_host *host, u8 mask)
 
 	sdhci_writeb(host, mask, SDHCI_SOFTWARE_RESET);
 
-	if (mask & SDHCI_RESET_ALL)
+	if (mask & SDHCI_RESET_ALL) {
 		host->clock = 0;
+		/* Reset-all turns off SD Bus Power */
+		if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON)
+			sdhci_runtime_pm_bus_off(host);
+	}
 
 	/* Wait max 100 ms */
 	timeout = 100;

@@ -1268,6 +1280,8 @@ static int sdhci_set_power(struct sdhci_host *host, unsigned short power)
 
 	if (pwr == 0) {
 		sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+		if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON)
+			sdhci_runtime_pm_bus_off(host);
 		return 0;
 	}
 

@@ -1289,6 +1303,9 @@ static int sdhci_set_power(struct sdhci_host *host, unsigned short power)
 
 	sdhci_writeb(host, pwr, SDHCI_POWER_CONTROL);
 
+	if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON)
+		sdhci_runtime_pm_bus_on(host);
+
 	/*
 	 * Some controllers need an extra 10ms delay of 10ms before they
 	 * can apply clock after applying power

@@ -2625,6 +2642,22 @@ static int sdhci_runtime_pm_put(struct sdhci_host *host)
 	return pm_runtime_put_autosuspend(host->mmc->parent);
 }
 
+static void sdhci_runtime_pm_bus_on(struct sdhci_host *host)
+{
+	if (host->runtime_suspended || host->bus_on)
+		return;
+	host->bus_on = true;
+	pm_runtime_get_noresume(host->mmc->parent);
+}
+
+static void sdhci_runtime_pm_bus_off(struct sdhci_host *host)
+{
+	if (host->runtime_suspended || !host->bus_on)
+		return;
+	host->bus_on = false;
+	pm_runtime_put_noidle(host->mmc->parent);
+}
+
 int sdhci_runtime_suspend_host(struct sdhci_host *host)
 {
 	unsigned long flags;

index b838ffc..ba35bdb 100644
@@ -95,6 +95,7 @@ struct sdhci_host {
 /* The system physically doesn't support 1.8v, even if the host does */
 #define SDHCI_QUIRK2_NO_1_8_V				(1<<2)
 #define SDHCI_QUIRK2_PRESET_VALUE_BROKEN		(1<<3)
+#define SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON		(1<<4)
 
 	int irq;		/* Device IRQ */
 	void __iomem *ioaddr;	/* Mapped address */

@@ -139,6 +140,7 @@ struct sdhci_host {
 	u8 pwr;			/* Current voltage */
 
 	bool runtime_suspended;	/* Host is runtime suspended */
+	bool bus_on;		/* Bus power prevents runtime suspend */
 
 	struct mmc_request *mrq;	/* Current request */
 	struct mmc_command *cmd;	/* Current command */

index 706d9cb..17fceba 100644
@@ -31,8 +31,10 @@
 #include <linux/bitops.h>
 #include <linux/types.h>
 #include <linux/err.h>
+#include <linux/gpio.h>
 #include <linux/interrupt.h>
 #include <linux/acpi.h>
+#include <linux/acpi_gpio.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
 

@@ -101,6 +103,8 @@ static const struct sdhci_acpi_slot sdhci_acpi_slot_int_sdio = {
 };
 
 static const struct sdhci_acpi_slot sdhci_acpi_slot_int_sd = {
+	.flags   = SDHCI_ACPI_SD_CD | SDHCI_ACPI_RUNTIME_PM,
+	.quirks2 = SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON,
 };
 
 struct sdhci_acpi_uid_slot {

@@ -161,6 +165,57 @@ static const struct sdhci_acpi_slot *sdhci_acpi_get_slot(acpi_handle handle,
 	return slot;
 }
 
+#ifdef CONFIG_PM_RUNTIME
+
+static irqreturn_t sdhci_acpi_sd_cd(int irq, void *dev_id)
+{
+	mmc_detect_change(dev_id, msecs_to_jiffies(200));
+	return IRQ_HANDLED;
+}
+
+static int sdhci_acpi_add_own_cd(struct device *dev, int gpio,
+				 struct mmc_host *mmc)
+{
+	unsigned long flags;
+	int err, irq;
+
+	if (gpio < 0) {
+		err = gpio;
+		goto out;
+	}
+
+	err = devm_gpio_request_one(dev, gpio, GPIOF_DIR_IN, "sd_cd");
+	if (err)
+		goto out;
+
+	irq = gpio_to_irq(gpio);
+	if (irq < 0)
+		goto out_free;
+
+	flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
+	err = devm_request_irq(dev, irq, sdhci_acpi_sd_cd, flags, "sd_cd", mmc);
+	if (err)
+		goto out_free;
+
+	return 0;
+
+out_free:
+	devm_gpio_free(dev, gpio);
+out:
+	dev_warn(dev, "failed to setup card detect wake up\n");
+	return err;
+}
+
+#else
+
+static int sdhci_acpi_add_own_cd(struct device *dev, int gpio,
+				 struct mmc_host *mmc)
+{
+	return 0;
+}
+
+#endif
+
 static int sdhci_acpi_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;

@@ -171,7 +226,7 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
 	struct resource *iomem;
 	resource_size_t len;
 	const char *hid;
-	int err;
+	int err, gpio;
 
 	if (acpi_bus_get_device(handle, &device))
 		return -ENODEV;

@@ -196,6 +251,8 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
 	if (IS_ERR(host))
 		return PTR_ERR(host);
 
+	gpio = acpi_get_gpio_by_index(dev, 0, NULL);
+
 	c = sdhci_priv(host);
 	c->host = host;
 	c->slot = sdhci_acpi_get_slot(handle, hid);

@@ -251,6 +308,11 @@ static int sdhci_acpi_probe(struct platform_device *pdev)
 	if (err)
 		goto err_free;
 
+	if (sdhci_acpi_flag(c, SDHCI_ACPI_SD_CD)) {
+		if (sdhci_acpi_add_own_cd(dev, gpio, host->mmc))
+			c->use_runtime_pm = false;
+	}
+
 	if (c->use_runtime_pm) {
 		pm_runtime_set_active(dev);
 		pm_suspend_ignore_children(dev, 1);

index 701d06d..611331a 100644
@@ -332,6 +332,8 @@ static const struct sdhci_pci_fixes sdhci_intel_byt_sdio = {
 };
 
 static const struct sdhci_pci_fixes sdhci_intel_byt_sd = {
+	.quirks2	= SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON,
+	.allow_runtime_pm = true,
 };
 
 /* O2Micro extra registers */