[PATCH V2] mmc: sdhci-msm: Update system suspend/resume callbacks of sdhci-msm platform driver.

[PATCH V2] mmc: sdhci-msm: Update system suspend/resume callbacks of sdhci-msm platform driver.

[Shaik Sajida Bhanu]

The existing suspend/resume callbacks of sdhci-msm driver are just
gating/un-gating the clocks. During suspend cycle more can be done
like disabling controller, interrupts and card detection.

So updating the system pm callbacks for performing these extra
actions besides controlling the clocks.

Signed-off-by: Shaik Sajida Bhanu <sbhanu@codeaurora.org>

Changes since V1:
	Addressed review comments
---
 drivers/mmc/host/sdhci-msm.c | 50 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 48 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index c3a160c..e30c8a3 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -2159,9 +2159,55 @@ static __maybe_unused int sdhci_msm_runtime_resume(struct device *dev)
 	return 0;
 }
 
+static int sdhci_msm_suspend(struct device *dev)
+{
+	struct sdhci_host *host = dev_get_drvdata(dev);
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
+	int ret;
+
+	if (host->mmc->caps2 & MMC_CAP2_CQE) {
+		ret = cqhci_suspend(host->mmc);
+		if (ret)
+			return ret;
+	}
+
+	ret = sdhci_suspend_host(host);
+	if (ret)
+		return ret;
+	/* Disable pwr-irq since SDHC would be inactive */
+	disable_irq(msm_host->pwr_irq);
+
+	return pm_runtime_force_suspend(dev);
+}
+
+static int sdhci_msm_resume(struct device *dev)
+{
+	struct sdhci_host *host = dev_get_drvdata(dev);
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
+	int ret;
+
+	ret = pm_runtime_force_resume(dev);
+	if (ret)
+		return ret;
+
+	/* Re-enable pwr irq before SDHC gets reset */
+	enable_irq(msm_host->pwr_irq);
+
+	ret = sdhci_resume_host(host);
+	if (ret < 0)
+		return ret;
+
+	if (host->mmc->caps2 & MMC_CAP2_CQE)
+		ret = cqhci_resume(host->mmc);
+
+	return ret;
+}
+
 static const struct dev_pm_ops sdhci_msm_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
-				pm_runtime_force_resume)
+	SET_SYSTEM_SLEEP_PM_OPS(sdhci_msm_suspend,
+				sdhci_msm_resume)
 	SET_RUNTIME_PM_OPS(sdhci_msm_runtime_suspend,
 			   sdhci_msm_runtime_resume,
 			   NULL)
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member 
of Code Aurora Forum, hosted by The Linux Foundation

Re: [PATCH V2] mmc: sdhci-msm: Update system suspend/resume callbacks of sdhci-msm platform driver.

[Stephen Boyd]

Quoting Shaik Sajida Bhanu (2020-02-07 05:20:50)
> The existing suspend/resume callbacks of sdhci-msm driver are just
> gating/un-gating the clocks. During suspend cycle more can be done
> like disabling controller, interrupts and card detection.
> 
> So updating the system pm callbacks for performing these extra
> actions besides controlling the clocks.
> 
> Signed-off-by: Shaik Sajida Bhanu <sbhanu@codeaurora.org>
> 
> Changes since V1:
>         Addressed review comments

Please don't write this. Instead, describe what's actually different so
the reader doesn't have to go figure out what the review comments were.

> ---
>  drivers/mmc/host/sdhci-msm.c | 50 ++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 48 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index c3a160c..e30c8a3 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -2159,9 +2159,55 @@ static __maybe_unused int sdhci_msm_runtime_resume(struct device *dev)
>         return 0;
>  }
>  
> +static int sdhci_msm_suspend(struct device *dev)
> +{
> +       struct sdhci_host *host = dev_get_drvdata(dev);
> +       struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +       struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> +       int ret;
> +
> +       if (host->mmc->caps2 & MMC_CAP2_CQE) {
> +               ret = cqhci_suspend(host->mmc);
> +               if (ret)
> +                       return ret;
> +       }
> +
> +       ret = sdhci_suspend_host(host);
> +       if (ret)
> +               return ret;
> +       /* Disable pwr-irq since SDHC would be inactive */
> +       disable_irq(msm_host->pwr_irq);

Why do we need to do this? If it's inactive then the irq won't be raised
by the inactive hardware. Given that we're going to suspend the device,
the irq won't matter unless it's marked for wakeup. Please remove this
irq enable/disable logic, or explain why it's really needed.

> +
> +       return pm_runtime_force_suspend(dev);
> +}
> +

Re: [PATCH V2] mmc: sdhci-msm: Update system suspend/resume callbacks of sdhci-msm platform driver.

[sbhanu]

On 2020-02-11 01:11, Stephen Boyd wrote:
> Quoting Shaik Sajida Bhanu (2020-02-07 05:20:50)
>> The existing suspend/resume callbacks of sdhci-msm driver are just
>> gating/un-gating the clocks. During suspend cycle more can be done
>> like disabling controller, interrupts and card detection.
>> 
>> So updating the system pm callbacks for performing these extra
>> actions besides controlling the clocks.
>> 
>> Signed-off-by: Shaik Sajida Bhanu <sbhanu@codeaurora.org>
>> 
>> Changes since V1:
>>         Addressed review comments
> 
> Please don't write this. Instead, describe what's actually different so
> the reader doesn't have to go figure out what the review comments were.
> 

sure

>> ---
>>  drivers/mmc/host/sdhci-msm.c | 50 
>> ++++++++++++++++++++++++++++++++++++++++++--
>>  1 file changed, 48 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/mmc/host/sdhci-msm.c 
>> b/drivers/mmc/host/sdhci-msm.c
>> index c3a160c..e30c8a3 100644
>> --- a/drivers/mmc/host/sdhci-msm.c
>> +++ b/drivers/mmc/host/sdhci-msm.c
>> @@ -2159,9 +2159,55 @@ static __maybe_unused int 
>> sdhci_msm_runtime_resume(struct device *dev)
>>         return 0;
>>  }
>> 
>> +static int sdhci_msm_suspend(struct device *dev)
>> +{
>> +       struct sdhci_host *host = dev_get_drvdata(dev);
>> +       struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>> +       struct sdhci_msm_host *msm_host = 
>> sdhci_pltfm_priv(pltfm_host);
>> +       int ret;
>> +
>> +       if (host->mmc->caps2 & MMC_CAP2_CQE) {
>> +               ret = cqhci_suspend(host->mmc);
>> +               if (ret)
>> +                       return ret;
>> +       }
>> +
>> +       ret = sdhci_suspend_host(host);
>> +       if (ret)
>> +               return ret;
>> +       /* Disable pwr-irq since SDHC would be inactive */
>> +       disable_irq(msm_host->pwr_irq);
> 
> Why do we need to do this? If it's inactive then the irq won't be 
> raised
> by the inactive hardware. Given that we're going to suspend the device,
> the irq won't matter unless it's marked for wakeup. Please remove this
> irq enable/disable logic, or explain why it's really needed.
> 

You are right. This is not needed.
We have checked more on this and interrupt are getting disabled in 
suspend_device_irqs().
Will remove this.

>> +
>> +       return pm_runtime_force_suspend(dev);
>> +}
>> +