diff mbox series

[v5,3/3] mmc: mediatek: add support for SDIO eint IRQ

Message ID 20220121071942.11601-4-axe.yang@mediatek.com
State New
Headers show
Series mmc: mediatek: add support for SDIO async IRQ | expand

Commit Message

Axe Yang Jan. 21, 2022, 7:19 a.m. UTC
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 <yong.mao@mediatek.com>
Signed-off-by: Yong Mao <yong.mao@mediatek.com>
Signed-off-by: Axe Yang <axe.yang@mediatek.com>
---
 drivers/mmc/host/mtk-sd.c | 123 +++++++++++++++++++++++++++++++++++---
 1 file changed, 115 insertions(+), 8 deletions(-)

Comments

Chaotian Jing (井朝天) Jan. 27, 2022, 3:31 a.m. UTC | #1
On Fri, 2022-01-21 at 15:19 +0800, Axe Yang wrote:
> 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 <yong.mao@mediatek.com>
> Signed-off-by: Yong Mao <yong.mao@mediatek.com>
> Signed-off-by: Axe Yang <axe.yang@mediatek.com>
Acked-by: Chaotian Jing <chaotian.jing@mediatek.com>
> ---
>  drivers/mmc/host/mtk-sd.c | 123 +++++++++++++++++++++++++++++++++++-
> --
>  1 file changed, 115 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> index 65037e1d7723..f8e38228d810 100644
> --- a/drivers/mmc/host/mtk-sd.c
> +++ b/drivers/mmc/host/mtk-sd.c
> @@ -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 <chaotian.jing@mediatek.com>
>   */
>  
> @@ -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)
>  };
>
Ulf Hansson Feb. 14, 2022, 3:54 p.m. UTC | #2
On Fri, 21 Jan 2022 at 08:19, Axe Yang <axe.yang@mediatek.com> wrote:
>
> 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";

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

>                 ...
>                 pinctrl-2 = <&mmc2_pins_eint>;
>                 pinctrl-3 = <&mmc2_pins_dat1>;
>                 ...
>                 cap-sdio-async-irq;
>                 ...
>         };
>
> Co-developed-by: Yong Mao <yong.mao@mediatek.com>
> Signed-off-by: Yong Mao <yong.mao@mediatek.com>
> Signed-off-by: Axe Yang <axe.yang@mediatek.com>
> ---
>  drivers/mmc/host/mtk-sd.c | 123 +++++++++++++++++++++++++++++++++++---
>  1 file changed, 115 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> index 65037e1d7723..f8e38228d810 100644
> --- a/drivers/mmc/host/mtk-sd.c
> +++ b/drivers/mmc/host/mtk-sd.c
> @@ -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 <chaotian.jing@mediatek.com>
>   */
>
> @@ -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);

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

> +       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)
>  };
>

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.

Kind regards
Uffe
Axe Yang Feb. 21, 2022, 7:36 a.m. UTC | #3
On Mon, 2022-02-14 at 16:54 +0100, Ulf Hansson wrote:
> On Fri, 21 Jan 2022 at 08:19, Axe Yang <axe.yang@mediatek.com> wrote:
> > 
> > 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";
> 
> Looks like you need to update the DT docs too to describe these new
> things, right?
Will update the docs in next patchset.

> 
> >                 ...
> >                 pinctrl-2 = <&mmc2_pins_eint>;
> >                 pinctrl-3 = <&mmc2_pins_dat1>;
> >                 ...
> >                 cap-sdio-async-irq;
> >                 ...
> >         };
> > 
> > Co-developed-by: Yong Mao <yong.mao@mediatek.com>
> > Signed-off-by: Yong Mao <yong.mao@mediatek.com>
> > Signed-off-by: Axe Yang <axe.yang@mediatek.com>
> > ---
> >  drivers/mmc/host/mtk-sd.c | 123
> > +++++++++++++++++++++++++++++++++++---
> >  1 file changed, 115 insertions(+), 8 deletions(-)
> > 
> > diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> > index 65037e1d7723..f8e38228d810 100644
> > --- a/drivers/mmc/host/mtk-sd.c
> > +++ b/drivers/mmc/host/mtk-sd.c
> > @@ -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 <chaotian.jing@mediatek.com>
> >   */
> > 
> > @@ -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);
> 
> Again, I think you need to update the DT doc to describe these new
> IRQ/GPIO things.
Will update the docs in next patchset.

> 
> > +       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)
> >  };
> > 
> 
> 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.
Will read the wakeirq interfaces and use them in next version. Thanks
for review.

Regards,
Axe Yang
diff mbox series

Patch

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index 65037e1d7723..f8e38228d810 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -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 <chaotian.jing@mediatek.com>
  */
 
@@ -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)
 };