mmc: mediatek: add support for SDIO async IRQ

index b589df1c35e0..0b682a31cd3e 100644
@@ -226,6 +226,20 @@ static int sdio_read_cccr(struct mmc_card *card, u32 ocr)
 				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_C;
 			if (data & SDIO_DRIVE_SDTD)
 				card->sw_caps.sd3_drv_type |= SD_DRIVER_TYPE_D;
+
+			ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTERRUPT_EXT, 0, &data);
+			if (ret)
+				goto out;
+
+			if (data & SDIO_INTERRUPT_EXT_SAI) {
+				data |= SDIO_INTERRUPT_EXT_EAI;
+				ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_INTERRUPT_EXT,
+						       data, NULL);
+				if (ret)
+					goto out;
+
+				card->cccr.enable_async_irq = 1;
+			}
 		}
 
 		/* if no uhs mode ensure we check for high speed */

index 156a7b673a28..8a30de08e913 100644
@@ -219,7 +219,8 @@ struct sdio_cccr {
 				wide_bus:1,
 				high_power:1,
 				high_speed:1,
-				disable_cd:1;
+				disable_cd:1,
+				enable_async_irq:1;
 };
 
 struct sdio_cis {

@@ -343,6 +344,11 @@ static inline bool mmc_large_sector(struct mmc_card *card)
 	return card->ext_csd.data_sector_size == 4096;
 }
 
+static inline int mmc_card_enable_async_irq(struct mmc_card *card)
+{
+	return card->cccr.enable_async_irq;
+}
+
 bool mmc_card_is_blockaddr(struct mmc_card *card);
 
 #define mmc_card_mmc(c)		((c)->type == MMC_TYPE_MMC)

index 2a05d1ac4f0e..1ef400f28642 100644
@@ -159,6 +159,11 @@
 #define  SDIO_DTSx_SET_TYPE_A	(1 << SDIO_DRIVE_DTSx_SHIFT)
 #define  SDIO_DTSx_SET_TYPE_C	(2 << SDIO_DRIVE_DTSx_SHIFT)
 #define  SDIO_DTSx_SET_TYPE_D	(3 << SDIO_DRIVE_DTSx_SHIFT)
+
+#define SDIO_CCCR_INTERRUPT_EXT	0x16
+#define SDIO_INTERRUPT_EXT_SAI	(1 << 0)
+#define SDIO_INTERRUPT_EXT_EAI	(1 << 1)
+
 /*
  * Function Basic Registers (FBR)
  */

index a4954b200d87..4ff73d1883de 100644
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (c) 2014-2015 MediaTek Inc.
+ * Copyright (c) 2014-2015, 2022 MediaTek Inc.
  * Author: Chaotian.Jing <[email protected]>
  */
 

@@ -20,6 +20,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
+#include <linux/pm_wakeirq.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>

@@ -440,8 +441,10 @@ struct msdc_host {
 	struct pinctrl *pinctrl;
 	struct pinctrl_state *pins_default;
 	struct pinctrl_state *pins_uhs;
+	struct pinctrl_state *pins_eint;
 	struct delayed_work req_timeout;
 	int irq;		/* host interrupt */
+	int eint_irq;		/* interrupt from sdio device for waking up system */
 	struct reset_control *reset;
 
 	struct clk *src_clk;	/* msdc source clock */

@@ -1521,17 +1524,46 @@ static void __msdc_enable_sdio_irq(struct msdc_host *host, int enb)
 
 static void msdc_enable_sdio_irq(struct mmc_host *mmc, int enb)
 {
-	unsigned long flags;
 	struct msdc_host *host = mmc_priv(mmc);
+	unsigned long flags;
+	int ret;
 
 	spin_lock_irqsave(&host->lock, flags);
 	__msdc_enable_sdio_irq(host, enb);
 	spin_unlock_irqrestore(&host->lock, flags);
 
-	if (enb)
-		pm_runtime_get_noresume(host->dev);
-	else
-		pm_runtime_put_noidle(host->dev);
+	if (mmc_card_enable_async_irq(mmc->card) && host->pins_eint) {
+		if (enb) {
+			/*
+			 * In dev_pm_set_dedicated_wake_irq_reverse(), eint pin will be set to
+			 * GPIO mode. We need to restore it to SDIO DAT1 mode after that.
+			 * Since the current pinstate is pins_uhs, to ensure pinctrl select take
+			 * affect successfully, we change the pinstate to pins_eint firstly.
+			 */
+			pinctrl_select_state(host->pinctrl, host->pins_eint);
+			ret = dev_pm_set_dedicated_wake_irq_reverse(host->dev, host->eint_irq);
+
+			if (ret) {
+				dev_err(host->dev, "Failed to register SDIO wakeup irq!\n");
+				host->pins_eint = NULL;
+				pm_runtime_get_noresume(host->dev);
+			} else {
+				dev_dbg(host->dev, "SDIO eint irq: %d!\n", host->eint_irq);
+			}
+
+			pinctrl_select_state(host->pinctrl, host->pins_uhs);
+		} else {
+			dev_pm_clear_wake_irq(host->dev);
+		}
+	} else {
+		if (enb) {
+			/* Ensure host->pins_eint is NULL */
+			host->pins_eint = NULL;
+			pm_runtime_get_noresume(host->dev);
+		} else {
+			pm_runtime_put_noidle(host->dev);
+		}
+	}
 }
 
 static irqreturn_t msdc_cmdq_irq(struct msdc_host *host, u32 intsts)

@@ -2635,6 +2667,20 @@ static int msdc_drv_probe(struct platform_device *pdev)
 		goto host_free;
 	}
 
+	/* Support for SDIO eint irq ? */
+	if ((mmc->pm_caps & MMC_PM_WAKE_SDIO_IRQ) && (mmc->pm_caps & MMC_PM_KEEP_POWER)) {
+		host->eint_irq = platform_get_irq_byname(pdev, "sdio_wakeup");
+		if (host->eint_irq > 0) {
+			host->pins_eint = pinctrl_lookup_state(host->pinctrl, "state_eint");
+			if (IS_ERR(host->pins_eint)) {
+				dev_err(&pdev->dev, "Cannot find pinctrl eint!\n");
+				host->pins_eint = NULL;
+			} else {
+				device_init_wakeup(&pdev->dev, true);
+			}
+		}
+	}
+
 	msdc_of_property_parse(pdev, host);
 
 	host->dev = &pdev->dev;

@@ -2849,6 +2895,15 @@ static int __maybe_unused msdc_runtime_suspend(struct device *dev)
 	struct msdc_host *host = mmc_priv(mmc);
 
 	msdc_save_reg(host);
+
+	if (sdio_irq_claimed(mmc)) {
+		if (host->pins_eint) {
+			disable_irq(host->irq);
+			pinctrl_select_state(host->pinctrl, host->pins_eint);
+		}
+
+		__msdc_enable_sdio_irq(host, 0);
+	}
 	msdc_gate_clock(host);
 	return 0;
 }

@@ -2864,12 +2919,18 @@ static int __maybe_unused msdc_runtime_resume(struct device *dev)
 		return ret;
 
 	msdc_restore_reg(host);
+
+	if (sdio_irq_claimed(mmc) && host->pins_eint) {
+		pinctrl_select_state(host->pinctrl, host->pins_uhs);
+		enable_irq(host->irq);
+	}
 	return 0;
 }
 
 static int __maybe_unused msdc_suspend(struct device *dev)
 {
 	struct mmc_host *mmc = dev_get_drvdata(dev);
+	struct msdc_host *host = mmc_priv(mmc);
 	int ret;
 
 	if (mmc->caps2 & MMC_CAP2_CQE) {

@@ -2878,11 +2939,24 @@ static int __maybe_unused msdc_suspend(struct device *dev)
 			return ret;
 	}
 
+	/*
+	 * Bump up runtime PM usage counter otherwise dev->power.needs_force_resume will
+	 * not be marked as 1, pm_runtime_force_resume() will go out directly.
+	 */
+	if (sdio_irq_claimed(mmc) && host->pins_eint)
+		pm_runtime_get_noresume(dev);
+
 	return pm_runtime_force_suspend(dev);
 }
 
 static int __maybe_unused msdc_resume(struct device *dev)
 {
+	struct mmc_host *mmc = dev_get_drvdata(dev);
+	struct msdc_host *host = mmc_priv(mmc);
+
+	if (sdio_irq_claimed(mmc) && host->pins_eint)
+		pm_runtime_put_noidle(dev);
+
 	return pm_runtime_force_resume(dev);
 }