mmc: mediatek: add support for SDIO async IRQ

Asynchronous interrupt is a mechanism that allow SDIO devices alarm interrupt when host stop providing clock to card. Add a DT flag to enable this feature if it is supported by SDIO card.

Signed-off-by Axe Yang <[email protected]>

---
 Documentation/devicetree/bindings/mmc/mmc-controller.yaml | 5 +++++
 1 file changed, 5 insertions(+)

If cap-sdio-async-irq flag is set in host dts node, parse EAI information from SDIO CCCR interrupt externsion segment. If async interrupt is supported by SDIO card then send command to card to enable it and set enable_async_irq flag in sdio_cccr structure to 1. The parse flow is implemented in sdio_read_cccr().

Acked-by AngeloGioacchino Del Regno <[email protected]>

Signed-off-by Axe Yang <[email protected]>

---
 drivers/mmc/core/host.c  |  2 ++
 drivers/mmc/core/sdio.c  | 17 +++++++++++++++++
 include/linux/mmc/card.h |  3 ++-
 include/linux/mmc/host.h |  1 +
 include/linux/mmc/sdio.h |  5 +++++
 5 files changed, 27 insertions(+), 1 deletion(-)

drivers/mmc/core/host.c +2 -0

index cf140f4ec864..a972241548b4 100644
@@ -410,6 +410,8 @@ int mmc_of_parse(struct mmc_host *host)
        if (device_property_read_bool(dev, "no-mmc-hs400"))
                host->caps2 &= ~(MMC_CAP2_HS400_1_8V | MMC_CAP2_HS400_1_2V |
                                 MMC_CAP2_HS400_ES);
+       if (device_property_read_bool(dev, "cap-sdio-async-irq"))
+               host->caps2 |= MMC_CAP2_SDIO_ASYNC_IRQ;
 
        /* Must be after "non-removable" check */
        if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {

drivers/mmc/core/sdio.c +0 -0

index 41164748723d..771fb5d18585 100644

drivers/mmc/core/sdio.c +2 -0

+                               }
+                       }
                }
 
                /* if no uhs mode ensure we check for high speed */

include/linux/mmc/card.h +2 -1

index 37f975875102..4df9182bc0e6 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 {

include/linux/mmc/host.h +1 -0

index 7afb57cab00b..502a5418264c 100644
@@ -402,6 +402,7 @@ struct mmc_host {
 #define MMC_CAP2_CRYPTO                0
 #endif
 #define MMC_CAP2_ALT_GPT_TEGRA (1 << 28)       /* Host with eMMC that has GPT entry at a non-standard location */
+#define MMC_CAP2_SDIO_ASYNC_IRQ        (1 << 29)       /* SDIO host supports asynchronous interrupt */
 
        int                     fixed_drv_type; /* fixed driver type for non-removable media */
 

include/linux/mmc/sdio.h +0 -0

index 2a05d1ac4f0e..1ef400f28642 100644
@@ -159,6 +159,11 @@
 #define  SDIO_DTSx_SET_TYPE_A  (1 << SDIO_DRIVE_DTSx_SHIFT)

Quoted 43 lines · Axe Yang

If cap-sdio-async-irq flag is set in host dts node, parse EAI information from SDIO CCCR interrupt externsion segment. If async interrupt is supported by SDIO card then send command to card to enable it and set enable_async_irq flag in sdio_cccr structure to 1.
The parse flow is implemented in sdio_read_cccr().

Acked-by: AngeloGioacchino Del Regno <
[email protected]>

Signed-off-by Axe Yang <[email protected]>

---
 drivers/mmc/core/host.c  |  2 ++
 drivers/mmc/core/sdio.c  | 17 +++++++++++++++++
 include/linux/mmc/card.h |  3 ++-
 include/linux/mmc/host.h |  1 +
 include/linux/mmc/sdio.h |  5 +++++
 5 files changed, 27 insertions(+), 1 deletion(-)

drivers/mmc/core/host.c +0 -0

index cf140f4ec864..a972241548b4 100644
@@ -410,6 +410,8 @@ int mmc_of_parse(struct mmc_host *host)
        if (device_property_read_bool(dev, "no-mmc-hs400"))
                host->caps2 &= ~(MMC_CAP2_HS400_1_8V |

MMC_CAP2_HS400_1_2V |

                                 MMC_CAP2_HS400_ES);

drivers/mmc/core/host.c +2 -0

+       if (device_property_read_bool(dev, "cap-sdio-async-irq"))
+               host->caps2 |= MMC_CAP2_SDIO_ASYNC_IRQ;
 
        /* Must be after "non-removable" check */
        if (device_property_read_u32(dev, "fixed-emmc-driver-type", 

&drv_type) == 0) {

drivers/mmc/core/sdio.c +0 -0

index 41164748723d..771fb5d18585 100644
@@ -225,6 +225,23 @@ 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)

Quoted 5 lines

drivers/mmc/core/sdio.c +2 -0

                                card->sw_caps.sd3_drv_type |=
 SD_DRIVER_TYPE_D;
+
+                       if (card->host->caps2 &

MMC_CAP2_SDIO_ASYNC_IRQ) {

We can probably check host->pm_caps & MMC_PM_WAKE_SDIO_IRQ here, instead of MMC_CAP2_SDIO_ASYNC_IRQ.

Quoted 19 lines

+ ret = mmc_io_rw_direct(card, 0, 0,
SDIO_CCCR_INTERRUPT_EXT, 0,

drivers/mmc/core/sdio.c +5 -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);

drivers/mmc/core/sdio.c +4 -0

+                                       if (ret)
+                                               goto out;
+
+                                       card->cccr.enable_async_irq 

Quoted 1 line

= 1;

As you show in the next patch(3), this flag is useful to read for the host driver.

However, rather than accessing this flag directly in the host driver, can you please add a helper function that takes a struct mmc_card* as in-parameter instead?

Quoted 35 lines

drivers/mmc/core/sdio.c +2 -0

+                               }
+                       }
                }
 
                /* if no uhs mode ensure we check for high speed */

include/linux/mmc/card.h +2 -1

index 37f975875102..4df9182bc0e6 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 {

include/linux/mmc/host.h +0 -0

index 7afb57cab00b..502a5418264c 100644
@@ -402,6 +402,7 @@ struct mmc_host {
 #define MMC_CAP2_CRYPTO                0
 #endif
 #define MMC_CAP2_ALT_GPT_TEGRA (1 << 28)       /* Host with eMMC

that has GPT entry at a non-standard location */
+#define MMC_CAP2_SDIO_ASYNC_IRQ (1 << 29) /* SDIO
host supports asynchronous interrupt */

int fixed_drv_type; /* fixed driver
type for non-removable media */

Quoted 6 lines

include/linux/mmc/sdio.h +0 -0

index 2a05d1ac4f0e..1ef400f28642 100644
@@ -159,6 +159,11 @@
 #define  SDIO_DTSx_SET_TYPE_A  (1 << SDIO_DRIVE_DTSx_SHIFT)

include/linux/mmc/sdio.h line 169

Quoted 10 lines

include/linux/mmc/sdio.h +5 -0

 #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)
  */

Add support for eint IRQ when MSDC is used as an SDIO host. This feature requires SDIO device support async IRQ function. With this feature, SDIO host can be awakened by SDIO card in suspend state, without additional pin.

MSDC driver will time-share the SDIO DAT1 pin. During suspend, MSDC turn off clock and switch SDIO DAT1 pin to GPIO mode. And during resume, switch GPIO function back to DAT1 mode then turn on clock.

Some device tree property should be added or modified in MSDC node to support SDIO eint IRQ. Pinctrls named state_dat1 and state_eint are mandatory. And cap-sdio-async-irq flag is necessary since this feature depends on asynchronous interrupt:

        &mmcX {
                ...
                pinctrl-names = "default", "state_uhs", "state_eint",
                                "state_dat1";
                ...
                pinctrl-2 = <&mmc2_pins_eint>;
                pinctrl-3 = <&mmc2_pins_dat1>;
                ...
                cap-sdio-async-irq;
                ...
        };

Co-developed-by Yong Mao <[email protected]>

Signed-off-by Yong Mao <[email protected]>

Signed-off-by Axe Yang <[email protected]>

---
 drivers/mmc/host/mtk-sd.c | 123 +++++++++++++++++++++++++++++++++++---
 1 file changed, 115 insertions(+), 8 deletions(-)

drivers/mmc/host/mtk-sd.c +115 -8

index 65037e1d7723..f8e38228d810 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]>
  */
 

@@ -9,6 +9,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
+#include <linux/gpio/consumer.h>
 #include <linux/iopoll.h>
 #include <linux/ioport.h>
 #include <linux/irq.h>

@@ -440,8 +441,12 @@ struct msdc_host {
 	struct pinctrl *pinctrl;
 	struct pinctrl_state *pins_default;
 	struct pinctrl_state *pins_uhs;
+	struct pinctrl_state *pins_eint;
+	struct pinctrl_state *pins_dat1;
 	struct delayed_work req_timeout;
 	int irq;		/* host interrupt */
+	int eint_irq;		/* device interrupt */
+	int sdio_irq_cnt;	/* irq enable cnt */
 	struct reset_control *reset;
 
 	struct clk *src_clk;	/* msdc source clock */

@@ -465,6 +470,7 @@ struct msdc_host {
 	bool hs400_tuning;	/* hs400 mode online tuning */
 	bool internal_cd;	/* Use internal card-detect logic */
 	bool cqhci;		/* support eMMC hw cmdq */
+	bool sdio_eint_ready;	/* Ready to support SDIO eint interrupt */
 	struct msdc_save_para save_para; /* used when gate HCLK */
 	struct msdc_tune_para def_tune_para; /* default tune setting */
 	struct msdc_tune_para saved_tune_para; /* tune result of CMD21/CMD19 */

@@ -1527,10 +1533,12 @@ static void msdc_enable_sdio_irq(struct mmc_host *mmc, int enb)
 	__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 && !mmc->card->cccr.enable_async_irq) {
+		if (enb)
+			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)

@@ -2461,6 +2469,48 @@ static const struct mmc_host_ops mt_msdc_ops = {
 	.hw_reset = msdc_hw_reset,
 };
 
+static irqreturn_t msdc_sdio_eint_irq(int irq, void *dev_id)
+{
+	struct msdc_host *host = dev_id;
+	struct mmc_host *mmc = mmc_from_priv(host);
+
+	spin_lock(&host->lock);
+	if (likely(host->sdio_irq_cnt > 0)) {
+		disable_irq_nosync(host->eint_irq);
+		disable_irq_wake(host->eint_irq);
+		host->sdio_irq_cnt--;
+	}
+	spin_unlock(&host->lock);
+
+	sdio_signal_irq(mmc);
+
+	return IRQ_HANDLED;
+}
+
+static int msdc_request_dat1_eint_irq(struct msdc_host *host)
+{
+	struct gpio_desc *desc;
+	int irq, ret;
+
+	desc = devm_gpiod_get(host->dev, "eint", GPIOD_IN);
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
+
+	irq = gpiod_to_irq(desc);
+	if (irq < 0)
+		return irq;
+
+	ret = devm_request_threaded_irq(host->dev, irq, NULL, msdc_sdio_eint_irq,
+					IRQF_TRIGGER_LOW | IRQF_ONESHOT | IRQF_NO_AUTOEN,
+					"sdio-eint", host);
+	if (ret)
+		return ret;
+
+	host->eint_irq = irq;
+
+	return 0;
+}
+
 static const struct cqhci_host_ops msdc_cmdq_ops = {
 	.enable         = msdc_cqe_enable,
 	.disable        = msdc_cqe_disable,

@@ -2631,6 +2681,23 @@ static int msdc_drv_probe(struct platform_device *pdev)
 		goto host_free;
 	}
 
+	if (!(mmc->caps2 & MMC_CAP2_NO_SDIO) && (mmc->caps2 & MMC_CAP2_SDIO_ASYNC_IRQ)) {
+		/* Support for SDIO eint irq */
+		host->pins_eint = pinctrl_lookup_state(host->pinctrl, "state_eint");
+		if (IS_ERR(host->pins_eint)) {
+			dev_dbg(&pdev->dev, "Cannot find pinctrl eint!\n");
+		} else {
+			host->pins_dat1 = pinctrl_lookup_state(host->pinctrl, "state_dat1");
+			if (IS_ERR(host->pins_dat1)) {
+				ret = dev_err_probe(&pdev->dev, PTR_ERR(host->pins_dat1),
+						    "Cannot find pinctrl dat1!\n");
+				goto host_free;
+			}
+
+			host->sdio_eint_ready = true;
+		}
+	}
+
 	msdc_of_property_parse(pdev, host);
 
 	host->dev = &pdev->dev;

@@ -2722,6 +2789,16 @@ static int msdc_drv_probe(struct platform_device *pdev)
 	if (ret)
 		goto release;
 
+	if (host->sdio_eint_ready) {
+		ret = msdc_request_dat1_eint_irq(host);
+		if (ret) {
+			dev_err(host->dev, "Failed to register data1 eint irq!\n");
+			goto release;
+		}
+
+		pinctrl_select_state(host->pinctrl, host->pins_dat1);
+	}
+
 	pm_runtime_set_active(host->dev);
 	pm_runtime_set_autosuspend_delay(host->dev, MTK_MMC_AUTOSUSPEND_DELAY);
 	pm_runtime_use_autosuspend(host->dev);

@@ -2843,8 +2920,22 @@ static int __maybe_unused msdc_runtime_suspend(struct device *dev)
 {
 	struct mmc_host *mmc = dev_get_drvdata(dev);
 	struct msdc_host *host = mmc_priv(mmc);
+	unsigned long flags;
 
 	msdc_save_reg(host);
+
+	if (host->sdio_eint_ready) {
+		disable_irq(host->irq);
+		pinctrl_select_state(host->pinctrl, host->pins_eint);
+		spin_lock_irqsave(&host->lock, flags);
+		if (host->sdio_irq_cnt == 0) {
+			enable_irq(host->eint_irq);
+			enable_irq_wake(host->eint_irq);
+			host->sdio_irq_cnt++;
+		}
+		sdr_clr_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE);
+		spin_unlock_irqrestore(&host->lock, flags);
+	}
 	msdc_gate_clock(host);
 	return 0;
 }

@@ -2853,6 +2944,7 @@ static int __maybe_unused msdc_runtime_resume(struct device *dev)
 {
 	struct mmc_host *mmc = dev_get_drvdata(dev);
 	struct msdc_host *host = mmc_priv(mmc);
+	unsigned long flags;
 	int ret;
 
 	ret = msdc_ungate_clock(host);

@@ -2860,10 +2952,25 @@ static int __maybe_unused msdc_runtime_resume(struct device *dev)
 		return ret;
 
 	msdc_restore_reg(host);
+
+	if (host->sdio_eint_ready) {
+		spin_lock_irqsave(&host->lock, flags);
+		if (host->sdio_irq_cnt > 0) {
+			disable_irq_nosync(host->eint_irq);
+			disable_irq_wake(host->eint_irq);
+			host->sdio_irq_cnt--;
+			sdr_set_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE);
+		} else {
+			sdr_clr_bits(host->base + MSDC_INTEN, MSDC_INTEN_SDIOIRQ);
+		}
+		spin_unlock_irqrestore(&host->lock, flags);
+		pinctrl_select_state(host->pinctrl, host->pins_uhs);
+		enable_irq(host->irq);
+	}
 	return 0;
 }
 
-static int __maybe_unused msdc_suspend(struct device *dev)
+static int __maybe_unused msdc_suspend_noirq(struct device *dev)
 {
 	struct mmc_host *mmc = dev_get_drvdata(dev);
 	int ret;

@@ -2877,13 +2984,13 @@ static int __maybe_unused msdc_suspend(struct device *dev)
 	return pm_runtime_force_suspend(dev);
 }
 
-static int __maybe_unused msdc_resume(struct device *dev)
+static int __maybe_unused msdc_resume_noirq(struct device *dev)
 {
 	return pm_runtime_force_resume(dev);
 }
 
 static const struct dev_pm_ops msdc_dev_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(msdc_suspend, msdc_resume)
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(msdc_suspend_noirq, msdc_resume_noirq)
 	SET_RUNTIME_PM_OPS(msdc_runtime_suspend, msdc_runtime_resume, NULL)
 };
 

Signature · 1 line

2.25.1

Add support for eint IRQ when MSDC is used as an SDIO host. This feature requires SDIO device support async IRQ function. With this feature, SDIO host can be awakened by SDIO card in suspend state, without additional pin.

MSDC driver will time-share the SDIO DAT1 pin. During suspend, MSDC turn off clock and switch SDIO DAT1 pin to GPIO mode. And during resume, switch GPIO function back to DAT1 mode then turn on clock.

Some device tree property should be added or modified in MSDC node to support SDIO eint IRQ. Pinctrls named state_dat1 and state_eint are mandatory. And cap-sdio-async-irq flag is necessary since this feature depends on asynchronous interrupt:

        &mmcX {
                ...
                pinctrl-names = "default", "state_uhs", "state_eint",
                                "state_dat1";
                ...
                pinctrl-2 = <&mmc2_pins_eint>;
                pinctrl-3 = <&mmc2_pins_dat1>;
                ...
                cap-sdio-async-irq;
                ...
        };

Co-developed-by Yong Mao <[email protected]>

Signed-off-by Yong Mao <[email protected]>

Signed-off-by Axe Yang <[email protected]>

---
 drivers/mmc/host/mtk-sd.c | 123 +++++++++++++++++++++++++++++++++++-
--
 1 file changed, 115 insertions(+), 8 deletions(-)

drivers/mmc/host/mtk-sd.c +7 -1

index 65037e1d7723..f8e38228d810 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]>
  */
 

@@ -9,6 +9,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
+#include <linux/gpio/consumer.h>
 #include <linux/iopoll.h>
 #include <linux/ioport.h>
 #include <linux/irq.h>

@@ -440,8 +441,12 @@ struct msdc_host {
 	struct pinctrl *pinctrl;
 	struct pinctrl_state *pins_default;
 	struct pinctrl_state *pins_uhs;
+	struct pinctrl_state *pins_eint;
+	struct pinctrl_state *pins_dat1;
 	struct delayed_work req_timeout;
 	int irq;		/* host interrupt */
+	int eint_irq;		/* device interrupt */
+	int sdio_irq_cnt;	/* irq enable cnt */
 	struct reset_control *reset;
 
 	struct clk *src_clk;	/* msdc source clock */

@@ -465,6 +470,7 @@ struct msdc_host {
 	bool hs400_tuning;	/* hs400 mode online tuning */
 	bool internal_cd;	/* Use internal card-detect logic */
 	bool cqhci;		/* support eMMC hw cmdq */
+	bool sdio_eint_ready;	/* Ready to support SDIO eint

interrupt */

drivers/mmc/host/mtk-sd.c +0 -0

 	struct msdc_save_para save_para; /* used when gate HCLK */
 	struct msdc_tune_para def_tune_para; /* default tune setting */
 	struct msdc_tune_para saved_tune_para; /* tune result of

CMD21/CMD19 */

drivers/mmc/host/mtk-sd.c +6 -4

@@ -1527,10 +1533,12 @@ static void msdc_enable_sdio_irq(struct
 mmc_host *mmc, int enb)
 	__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 && !mmc->card->cccr.enable_async_irq) {
+		if (enb)
+			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)

drivers/mmc/host/mtk-sd.c +42 -0

@@ -2461,6 +2469,48 @@ static const struct mmc_host_ops mt_msdc_ops =
 {
 	.hw_reset = msdc_hw_reset,
 };
 
+static irqreturn_t msdc_sdio_eint_irq(int irq, void *dev_id)
+{
+	struct msdc_host *host = dev_id;
+	struct mmc_host *mmc = mmc_from_priv(host);
+
+	spin_lock(&host->lock);
+	if (likely(host->sdio_irq_cnt > 0)) {
+		disable_irq_nosync(host->eint_irq);
+		disable_irq_wake(host->eint_irq);
+		host->sdio_irq_cnt--;
+	}
+	spin_unlock(&host->lock);
+
+	sdio_signal_irq(mmc);
+
+	return IRQ_HANDLED;
+}
+
+static int msdc_request_dat1_eint_irq(struct msdc_host *host)
+{
+	struct gpio_desc *desc;
+	int irq, ret;
+
+	desc = devm_gpiod_get(host->dev, "eint", GPIOD_IN);
+	if (IS_ERR(desc))
+		return PTR_ERR(desc);
+
+	irq = gpiod_to_irq(desc);
+	if (irq < 0)
+		return irq;
+
+	ret = devm_request_threaded_irq(host->dev, irq, NULL,
 msdc_sdio_eint_irq,
+					IRQF_TRIGGER_LOW | IRQF_ONESHOT
 | IRQF_NO_AUTOEN,
+					"sdio-eint", host);
+	if (ret)
+		return ret;
+
+	host->eint_irq = irq;
+
+	return 0;
+}
+

static const struct cqhci_host_ops msdc_cmdq_ops = {

drivers/mmc/host/mtk-sd.c +5 -0

 	.enable         = msdc_cqe_enable,
 	.disable        = msdc_cqe_disable,

@@ -2631,6 +2681,23 @@ static int msdc_drv_probe(struct
 platform_device *pdev)
 		goto host_free;
 	}
 
+	if (!(mmc->caps2 & MMC_CAP2_NO_SDIO) && (mmc->caps2 &
 MMC_CAP2_SDIO_ASYNC_IRQ)) {
+		/* Support for SDIO eint irq */
+		host->pins_eint = pinctrl_lookup_state(host->pinctrl,
 "state_eint");
+		if (IS_ERR(host->pins_eint)) {
+			dev_dbg(&pdev->dev, "Cannot find pinctrl

eint!\n");

drivers/mmc/host/mtk-sd.c +2 -0

+		} else {
+			host->pins_dat1 = pinctrl_lookup_state(host-

Quoted 1 line

pinctrl, "state_dat1");

drivers/mmc/host/mtk-sd.c +2 -0

+			if (IS_ERR(host->pins_dat1)) {
+				ret = dev_err_probe(&pdev->dev,

PTR_ERR(host->pins_dat1),

drivers/mmc/host/mtk-sd.c +1 -0

+						    "Cannot find

pinctrl dat1!\n");

drivers/mmc/host/mtk-sd.c +17 -0

+				goto host_free;
+			}
+
+			host->sdio_eint_ready = true;
+		}
+	}
+
 	msdc_of_property_parse(pdev, host);
 
 	host->dev = &pdev->dev;

@@ -2722,6 +2789,16 @@ static int msdc_drv_probe(struct
 platform_device *pdev)
 	if (ret)
 		goto release;
 
+	if (host->sdio_eint_ready) {
+		ret = msdc_request_dat1_eint_irq(host);
+		if (ret) {
+			dev_err(host->dev, "Failed to register data1
 eint irq!\n");
+			goto release;
+		}
+
+		pinctrl_select_state(host->pinctrl, host->pins_dat1);
+	}
+
 	pm_runtime_set_active(host->dev);

pm_runtime_set_autosuspend_delay(host->dev,
MTK_MMC_AUTOSUSPEND_DELAY);

drivers/mmc/host/mtk-sd.c +14 -0

 	pm_runtime_use_autosuspend(host->dev);

@@ -2843,8 +2920,22 @@ static int __maybe_unused
 msdc_runtime_suspend(struct device *dev)
 {
 	struct mmc_host *mmc = dev_get_drvdata(dev);
 	struct msdc_host *host = mmc_priv(mmc);
+	unsigned long flags;
 
 	msdc_save_reg(host);
+
+	if (host->sdio_eint_ready) {
+		disable_irq(host->irq);
+		pinctrl_select_state(host->pinctrl, host->pins_eint);
+		spin_lock_irqsave(&host->lock, flags);
+		if (host->sdio_irq_cnt == 0) {
+			enable_irq(host->eint_irq);
+			enable_irq_wake(host->eint_irq);
+			host->sdio_irq_cnt++;
+		}
+		sdr_clr_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE);
+		spin_unlock_irqrestore(&host->lock, flags);
+	}
 	msdc_gate_clock(host);
 	return 0;

}

drivers/mmc/host/mtk-sd.c +1 -0

@@ -2853,6 +2944,7 @@ static int __maybe_unused
 msdc_runtime_resume(struct device *dev)
 {
 	struct mmc_host *mmc = dev_get_drvdata(dev);
 	struct msdc_host *host = mmc_priv(mmc);
+	unsigned long flags;
 	int ret;
 

drivers/mmc/host/mtk-sd.c +16 -1

 	ret = msdc_ungate_clock(host);

@@ -2860,10 +2952,25 @@ static int __maybe_unused
 msdc_runtime_resume(struct device *dev)
 		return ret;
 
 	msdc_restore_reg(host);
+
+	if (host->sdio_eint_ready) {
+		spin_lock_irqsave(&host->lock, flags);
+		if (host->sdio_irq_cnt > 0) {
+			disable_irq_nosync(host->eint_irq);
+			disable_irq_wake(host->eint_irq);
+			host->sdio_irq_cnt--;
+			sdr_set_bits(host->base + SDC_CFG,
 SDC_CFG_SDIOIDE);
+		} else {
+			sdr_clr_bits(host->base + MSDC_INTEN,
 MSDC_INTEN_SDIOIRQ);
+		}
+		spin_unlock_irqrestore(&host->lock, flags);
+		pinctrl_select_state(host->pinctrl, host->pins_uhs);
+		enable_irq(host->irq);
+	}
 	return 0;
 }
 
-static int __maybe_unused msdc_suspend(struct device *dev)
+static int __maybe_unused msdc_suspend_noirq(struct device *dev)

{

drivers/mmc/host/mtk-sd.c +2 -2

 	struct mmc_host *mmc = dev_get_drvdata(dev);
 	int ret;

@@ -2877,13 +2984,13 @@ static int __maybe_unused msdc_suspend(struct
 device *dev)
 	return pm_runtime_force_suspend(dev);
 }
 
-static int __maybe_unused msdc_resume(struct device *dev)
+static int __maybe_unused msdc_resume_noirq(struct device *dev)
 {
 	return pm_runtime_force_resume(dev);
 }
 
 static const struct dev_pm_ops msdc_dev_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(msdc_suspend, msdc_resume)
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(msdc_suspend_noirq,
 msdc_resume_noirq)
 	SET_RUNTIME_PM_OPS(msdc_runtime_suspend, msdc_runtime_resume,

NULL)
};

Add support for eint IRQ when MSDC is used as an SDIO host. This feature requires SDIO device support async IRQ function. With this feature, SDIO host can be awakened by SDIO card in suspend state, without additional pin.

MSDC driver will time-share the SDIO DAT1 pin. During suspend, MSDC turn off clock and switch SDIO DAT1 pin to GPIO mode. And during resume, switch GPIO function back to DAT1 mode then turn on clock.

Some device tree property should be added or modified in MSDC node to support SDIO eint IRQ. Pinctrls named state_dat1 and state_eint are mandatory. And cap-sdio-async-irq flag is necessary since this feature depends on asynchronous interrupt:

        &mmcX {
                ...
                pinctrl-names = "default", "state_uhs", "state_eint",
                                "state_dat1";

                ...
                pinctrl-2 = <&mmc2_pins_eint>;
                pinctrl-3 = <&mmc2_pins_dat1>;
                ...
                cap-sdio-async-irq;
                ...
        };

Co-developed-by Yong Mao <[email protected]>

Signed-off-by Yong Mao <[email protected]>

Signed-off-by Axe Yang <[email protected]>

---
 drivers/mmc/host/mtk-sd.c | 123 +++++++++++++++++++++++++++++++++++---
 1 file changed, 115 insertions(+), 8 deletions(-)

drivers/mmc/host/mtk-sd.c +37 -5

index 65037e1d7723..f8e38228d810 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]>
  */
 

@@ -9,6 +9,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
+#include <linux/gpio/consumer.h>
 #include <linux/iopoll.h>
 #include <linux/ioport.h>
 #include <linux/irq.h>

@@ -440,8 +441,12 @@ struct msdc_host {
        struct pinctrl *pinctrl;
        struct pinctrl_state *pins_default;
        struct pinctrl_state *pins_uhs;
+       struct pinctrl_state *pins_eint;
+       struct pinctrl_state *pins_dat1;
        struct delayed_work req_timeout;
        int irq;                /* host interrupt */
+       int eint_irq;           /* device interrupt */
+       int sdio_irq_cnt;       /* irq enable cnt */
        struct reset_control *reset;
 
        struct clk *src_clk;    /* msdc source clock */

@@ -465,6 +470,7 @@ struct msdc_host {
        bool hs400_tuning;      /* hs400 mode online tuning */
        bool internal_cd;       /* Use internal card-detect logic */
        bool cqhci;             /* support eMMC hw cmdq */
+       bool sdio_eint_ready;   /* Ready to support SDIO eint interrupt */
        struct msdc_save_para save_para; /* used when gate HCLK */
        struct msdc_tune_para def_tune_para; /* default tune setting */
        struct msdc_tune_para saved_tune_para; /* tune result of CMD21/CMD19 */

@@ -1527,10 +1533,12 @@ static void msdc_enable_sdio_irq(struct mmc_host *mmc, int enb)
        __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 && !mmc->card->cccr.enable_async_irq) {
+               if (enb)
+                       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)

@@ -2461,6 +2469,48 @@ static const struct mmc_host_ops mt_msdc_ops = {
        .hw_reset = msdc_hw_reset,
 };
 
+static irqreturn_t msdc_sdio_eint_irq(int irq, void *dev_id)
+{
+       struct msdc_host *host = dev_id;
+       struct mmc_host *mmc = mmc_from_priv(host);
+
+       spin_lock(&host->lock);
+       if (likely(host->sdio_irq_cnt > 0)) {
+               disable_irq_nosync(host->eint_irq);
+               disable_irq_wake(host->eint_irq);
+               host->sdio_irq_cnt--;
+       }
+       spin_unlock(&host->lock);
+
+       sdio_signal_irq(mmc);
+
+       return IRQ_HANDLED;
+}
+
+static int msdc_request_dat1_eint_irq(struct msdc_host *host)
+{
+       struct gpio_desc *desc;
+       int irq, ret;
+
+       desc = devm_gpiod_get(host->dev, "eint", GPIOD_IN);

drivers/mmc/host/mtk-sd.c +67 -2

+       if (ret)
+               return ret;
+
+       host->eint_irq = irq;
+
+       return 0;
+}
+
 static const struct cqhci_host_ops msdc_cmdq_ops = {
        .enable         = msdc_cqe_enable,
        .disable        = msdc_cqe_disable,

@@ -2631,6 +2681,23 @@ static int msdc_drv_probe(struct platform_device *pdev)
                goto host_free;
        }
 
+       if (!(mmc->caps2 & MMC_CAP2_NO_SDIO) && (mmc->caps2 & MMC_CAP2_SDIO_ASYNC_IRQ)) {
+               /* Support for SDIO eint irq */
+               host->pins_eint = pinctrl_lookup_state(host->pinctrl, "state_eint");
+               if (IS_ERR(host->pins_eint)) {
+                       dev_dbg(&pdev->dev, "Cannot find pinctrl eint!\n");
+               } else {
+                       host->pins_dat1 = pinctrl_lookup_state(host->pinctrl, "state_dat1");
+                       if (IS_ERR(host->pins_dat1)) {
+                               ret = dev_err_probe(&pdev->dev, PTR_ERR(host->pins_dat1),
+                                                   "Cannot find pinctrl dat1!\n");
+                               goto host_free;
+                       }
+
+                       host->sdio_eint_ready = true;
+               }
+       }
+
        msdc_of_property_parse(pdev, host);
 
        host->dev = &pdev->dev;

@@ -2722,6 +2789,16 @@ static int msdc_drv_probe(struct platform_device *pdev)
        if (ret)
                goto release;
 
+       if (host->sdio_eint_ready) {
+               ret = msdc_request_dat1_eint_irq(host);
+               if (ret) {
+                       dev_err(host->dev, "Failed to register data1 eint irq!\n");
+                       goto release;
+               }
+
+               pinctrl_select_state(host->pinctrl, host->pins_dat1);
+       }
+
        pm_runtime_set_active(host->dev);
        pm_runtime_set_autosuspend_delay(host->dev, MTK_MMC_AUTOSUSPEND_DELAY);
        pm_runtime_use_autosuspend(host->dev);

@@ -2843,8 +2920,22 @@ static int __maybe_unused msdc_runtime_suspend(struct device *dev)
 {
        struct mmc_host *mmc = dev_get_drvdata(dev);
        struct msdc_host *host = mmc_priv(mmc);
+       unsigned long flags;
 
        msdc_save_reg(host);
+
+       if (host->sdio_eint_ready) {
+               disable_irq(host->irq);
+               pinctrl_select_state(host->pinctrl, host->pins_eint);
+               spin_lock_irqsave(&host->lock, flags);
+               if (host->sdio_irq_cnt == 0) {
+                       enable_irq(host->eint_irq);
+                       enable_irq_wake(host->eint_irq);
+                       host->sdio_irq_cnt++;
+               }
+               sdr_clr_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE);
+               spin_unlock_irqrestore(&host->lock, flags);
+       }
        msdc_gate_clock(host);
        return 0;
 }

@@ -2853,6 +2944,7 @@ static int __maybe_unused msdc_runtime_resume(struct device *dev)
 {
        struct mmc_host *mmc = dev_get_drvdata(dev);
        struct msdc_host *host = mmc_priv(mmc);
+       unsigned long flags;
        int ret;
 
        ret = msdc_ungate_clock(host);

@@ -2860,10 +2952,25 @@ static int __maybe_unused msdc_runtime_resume(struct device *dev)
                return ret;
 
        msdc_restore_reg(host);
+
+       if (host->sdio_eint_ready) {
+               spin_lock_irqsave(&host->lock, flags);
+               if (host->sdio_irq_cnt > 0) {
+                       disable_irq_nosync(host->eint_irq);
+                       disable_irq_wake(host->eint_irq);
+                       host->sdio_irq_cnt--;
+                       sdr_set_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE);
+               } else {
+                       sdr_clr_bits(host->base + MSDC_INTEN, MSDC_INTEN_SDIOIRQ);
+               }
+               spin_unlock_irqrestore(&host->lock, flags);
+               pinctrl_select_state(host->pinctrl, host->pins_uhs);
+               enable_irq(host->irq);
+       }
        return 0;
 }
 
-static int __maybe_unused msdc_suspend(struct device *dev)
+static int __maybe_unused msdc_suspend_noirq(struct device *dev)
 {
        struct mmc_host *mmc = dev_get_drvdata(dev);
        int ret;

@@ -2877,13 +2984,13 @@ static int __maybe_unused msdc_suspend(struct device *dev)
        return pm_runtime_force_suspend(dev);
 }
 
-static int __maybe_unused msdc_resume(struct device *dev)
+static int __maybe_unused msdc_resume_noirq(struct device *dev)

Quoted 14 lines · Axe Yang

Add support for eint IRQ when MSDC is used as an SDIO host. This feature requires SDIO device support async IRQ function. With this feature, SDIO host can be awakened by SDIO card in suspend state, without additional pin.

MSDC driver will time-share the SDIO DAT1 pin. During suspend, MSDC turn off clock and switch SDIO DAT1 pin to GPIO mode. And during resume, switch GPIO function back to DAT1 mode then turn on clock.

Some device tree property should be added or modified in MSDC node to support SDIO eint IRQ. Pinctrls named state_dat1 and state_eint are mandatory. And cap-sdio-async-irq flag is necessary since this feature depends on asynchronous interrupt:

Quoted 5 lines

        &mmcX {
                ...
                pinctrl-names = "default", "state_uhs",
"state_eint",
                                "state_dat1";

Looks like you need to update the DT docs too to describe these new things, right?

Quoted 117 lines

                ...
                pinctrl-2 = <&mmc2_pins_eint>;
                pinctrl-3 = <&mmc2_pins_dat1>;
                ...
                cap-sdio-async-irq;
                ...
        };

Co-developed-by Yong Mao <[email protected]>

Signed-off-by Yong Mao <[email protected]>

Signed-off-by Axe Yang <[email protected]>

---
 drivers/mmc/host/mtk-sd.c | 123
+++++++++++++++++++++++++++++++++++---
 1 file changed, 115 insertions(+), 8 deletions(-)

drivers/mmc/host/mtk-sd.c +7 -1

index 65037e1d7723..f8e38228d810 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]>
  */
 

@@ -9,6 +9,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
+#include <linux/gpio/consumer.h>
 #include <linux/iopoll.h>
 #include <linux/ioport.h>
 #include <linux/irq.h>

@@ -440,8 +441,12 @@ struct msdc_host {
        struct pinctrl *pinctrl;
        struct pinctrl_state *pins_default;
        struct pinctrl_state *pins_uhs;
+       struct pinctrl_state *pins_eint;
+       struct pinctrl_state *pins_dat1;
        struct delayed_work req_timeout;
        int irq;                /* host interrupt */
+       int eint_irq;           /* device interrupt */
+       int sdio_irq_cnt;       /* irq enable cnt */
        struct reset_control *reset;
 
        struct clk *src_clk;    /* msdc source clock */

@@ -465,6 +470,7 @@ struct msdc_host {
        bool hs400_tuning;      /* hs400 mode online tuning */
        bool internal_cd;       /* Use internal card-detect logic
 */
        bool cqhci;             /* support eMMC hw cmdq */
+       bool sdio_eint_ready;   /* Ready to support SDIO eint

interrupt */
struct msdc_save_para save_para; /* used when gate HCLK */ struct msdc_tune_para def_tune_para; /* default tune
setting */
struct msdc_tune_para saved_tune_para; /* tune result of
CMD21/CMD19 */

drivers/mmc/host/mtk-sd.c +6 -4

@@ -1527,10 +1533,12 @@ static void msdc_enable_sdio_irq(struct
 mmc_host *mmc, int enb)
        __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 && !mmc->card->cccr.enable_async_irq) {
+               if (enb)
+                       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)

drivers/mmc/host/mtk-sd.c +31 -0

@@ -2461,6 +2469,48 @@ static const struct mmc_host_ops mt_msdc_ops
 = {
        .hw_reset = msdc_hw_reset,
 };
 
+static irqreturn_t msdc_sdio_eint_irq(int irq, void *dev_id)
+{
+       struct msdc_host *host = dev_id;
+       struct mmc_host *mmc = mmc_from_priv(host);
+
+       spin_lock(&host->lock);
+       if (likely(host->sdio_irq_cnt > 0)) {
+               disable_irq_nosync(host->eint_irq);
+               disable_irq_wake(host->eint_irq);
+               host->sdio_irq_cnt--;
+       }
+       spin_unlock(&host->lock);
+
+       sdio_signal_irq(mmc);
+
+       return IRQ_HANDLED;
+}
+
+static int msdc_request_dat1_eint_irq(struct msdc_host *host)
+{
+       struct gpio_desc *desc;
+       int irq, ret;
+
+       desc = devm_gpiod_get(host->dev, "eint", GPIOD_IN);
+       if (IS_ERR(desc))
+               return PTR_ERR(desc);
+
+       irq = gpiod_to_irq(desc);
+       if (irq < 0)
+               return irq;
+

drivers/mmc/host/mtk-sd.c static const struct mmc_host_ops mt_msdc_ops · line 2508

Quoted 5 lines

drivers/mmc/host/mtk-sd.c +3 -0

+       ret = devm_request_threaded_irq(host->dev, irq, NULL,
 msdc_sdio_eint_irq,
+                                       IRQF_TRIGGER_LOW |
 IRQF_ONESHOT | IRQF_NO_AUTOEN,
+                                       "sdio-eint", host);

Again, I think you need to update the DT doc to describe these new IRQ/GPIO things.

Quoted 146 lines

drivers/mmc/host/mtk-sd.c +8 -0

+       if (ret)
+               return ret;
+
+       host->eint_irq = irq;
+
+       return 0;
+}
+

static const struct cqhci_host_ops msdc_cmdq_ops = {
.enable = msdc_cqe_enable,
.disable = msdc_cqe_disable,

drivers/mmc/host/mtk-sd.c +5 -0

@@ -2631,6 +2681,23 @@ static int msdc_drv_probe(struct
 platform_device *pdev)
                goto host_free;
        }
 
+       if (!(mmc->caps2 & MMC_CAP2_NO_SDIO) && (mmc->caps2 &
 MMC_CAP2_SDIO_ASYNC_IRQ)) {
+               /* Support for SDIO eint irq */
+               host->pins_eint = pinctrl_lookup_state(host-
 >pinctrl, "state_eint");
+               if (IS_ERR(host->pins_eint)) {
+                       dev_dbg(&pdev->dev, "Cannot find pinctrl

eint!\n");

drivers/mmc/host/mtk-sd.c +2 -0

+               } else {
+                       host->pins_dat1 =

pinctrl_lookup_state(host->pinctrl, "state_dat1");

drivers/mmc/host/mtk-sd.c +2 -0

+                       if (IS_ERR(host->pins_dat1)) {
+                               ret = dev_err_probe(&pdev->dev,

PTR_ERR(host->pins_dat1),
+ "Cannot find
pinctrl dat1!\n");

drivers/mmc/host/mtk-sd.c +17 -0

+                               goto host_free;
+                       }
+
+                       host->sdio_eint_ready = true;
+               }
+       }
+
        msdc_of_property_parse(pdev, host);
 
        host->dev = &pdev->dev;

@@ -2722,6 +2789,16 @@ static int msdc_drv_probe(struct
 platform_device *pdev)
        if (ret)
                goto release;
 
+       if (host->sdio_eint_ready) {
+               ret = msdc_request_dat1_eint_irq(host);
+               if (ret) {
+                       dev_err(host->dev, "Failed to register
 data1 eint irq!\n");
+                       goto release;
+               }
+
+               pinctrl_select_state(host->pinctrl, host-
 >pins_dat1);
+       }
+

        pm_runtime_set_active(host->dev);
        pm_runtime_set_autosuspend_delay(host->dev,
MTK_MMC_AUTOSUSPEND_DELAY);
        pm_runtime_use_autosuspend(host->dev);

drivers/mmc/host/mtk-sd.c +14 -0

@@ -2843,8 +2920,22 @@ static int __maybe_unused
 msdc_runtime_suspend(struct device *dev)
 {
        struct mmc_host *mmc = dev_get_drvdata(dev);
        struct msdc_host *host = mmc_priv(mmc);
+       unsigned long flags;
 
        msdc_save_reg(host);
+
+       if (host->sdio_eint_ready) {
+               disable_irq(host->irq);
+               pinctrl_select_state(host->pinctrl, host-
 >pins_eint);
+               spin_lock_irqsave(&host->lock, flags);
+               if (host->sdio_irq_cnt == 0) {
+                       enable_irq(host->eint_irq);
+                       enable_irq_wake(host->eint_irq);
+                       host->sdio_irq_cnt++;
+               }
+               sdr_clr_bits(host->base + SDC_CFG,
 SDC_CFG_SDIOIDE);
+               spin_unlock_irqrestore(&host->lock, flags);
+       }

        msdc_gate_clock(host);
        return 0;

}

drivers/mmc/host/mtk-sd.c +1 -0

@@ -2853,6 +2944,7 @@ static int __maybe_unused
 msdc_runtime_resume(struct device *dev)
 {
        struct mmc_host *mmc = dev_get_drvdata(dev);
        struct msdc_host *host = mmc_priv(mmc);
+       unsigned long flags;
        int ret;
 

        ret = msdc_ungate_clock(host);

drivers/mmc/host/mtk-sd.c +18 -3

@@ -2860,10 +2952,25 @@ static int __maybe_unused
 msdc_runtime_resume(struct device *dev)
                return ret;
 
        msdc_restore_reg(host);
+
+       if (host->sdio_eint_ready) {
+               spin_lock_irqsave(&host->lock, flags);
+               if (host->sdio_irq_cnt > 0) {
+                       disable_irq_nosync(host->eint_irq);
+                       disable_irq_wake(host->eint_irq);
+                       host->sdio_irq_cnt--;
+                       sdr_set_bits(host->base + SDC_CFG,
 SDC_CFG_SDIOIDE);
+               } else {
+                       sdr_clr_bits(host->base + MSDC_INTEN,
 MSDC_INTEN_SDIOIRQ);
+               }
+               spin_unlock_irqrestore(&host->lock, flags);
+               pinctrl_select_state(host->pinctrl, host-
 >pins_uhs);
+               enable_irq(host->irq);
+       }
        return 0;
 }
 
-static int __maybe_unused msdc_suspend(struct device *dev)
+static int __maybe_unused msdc_suspend_noirq(struct device *dev)
 {
        struct mmc_host *mmc = dev_get_drvdata(dev);
        int ret;

@@ -2877,13 +2984,13 @@ static int __maybe_unused
 msdc_suspend(struct device *dev)
        return pm_runtime_force_suspend(dev);
 }
 
-static int __maybe_unused msdc_resume(struct device *dev)
+static int __maybe_unused msdc_resume_noirq(struct device *dev)
 {
        return pm_runtime_force_resume(dev);
 }
 
 static const struct dev_pm_ops msdc_dev_pm_ops = {
-       SET_SYSTEM_SLEEP_PM_OPS(msdc_suspend, msdc_resume)
+       SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(msdc_suspend_noirq,
 msdc_resume_noirq)
        SET_RUNTIME_PM_OPS(msdc_runtime_suspend,

Quoted 3 lines

msdc_runtime_resume, NULL)
};

Overall the approach makes perfect sense to me!

However, I think the code can be simplified and made more robust by using the wakeirq interface instead. Please have a look at dev_pm_set_dedicated_wake_irq() and friends. Using them, will let the runtime PM core deal with disabling/enabling the IRQ, rather than having to do that manually by the driver, for example.

If you want to get inspired by an existing implementation, please have
a look at the sdhci-omap driver.