[PATCH 2/2] mmc: sdhci-s3c: Enable runtime power management

[Jaehoon Chung]

Hi Mark,

On 03/03/2012 09:46 AM, Mark Brown wrote:

> Since most of the work is already done by the core we just need to add
> runtime suspend methods and tell the PM core that runtime PM is enabled
> for this device.
> 
> Signed-off-by: Mark Brown <broonie at opensource.wolfsonmicro.com>
> ---
>  drivers/mmc/host/sdhci-s3c.c |   28 ++++++++++++++++++++++++++++
>  1 files changed, 28 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
> index 46152d6..6926ac9 100644
> --- a/drivers/mmc/host/sdhci-s3c.c
> +++ b/drivers/mmc/host/sdhci-s3c.c
> @@ -23,6 +23,7 @@
>  #include <linux/of.h>
>  #include <linux/of_gpio.h>
>  #include <linux/pm.h>
> +#include <linux/pm_runtime.h>
>  
>  #include <linux/mmc/host.h>
>  
> @@ -721,6 +722,11 @@ static int __devinit sdhci_s3c_probe(struct platform_device *pdev)
>  	if (pdata->host_caps2)
>  		host->mmc->caps2 |= pdata->host_caps2;
>  
> +	pm_runtime_enable(&pdev->dev);
> +	pm_runtime_set_autosuspend_delay(&pdev->dev, 50);

Could you explain why use 50ms? 

> +	pm_runtime_use_autosuspend(&pdev->dev);
> +	pm_suspend_ignore_children(&pdev->dev, 1);

Is there reason that ignore_children use to set the true?

> +
>  	ret = sdhci_add_host(host);
>  	if (ret) {
>  		dev_err(dev, "sdhci_add_host() failed\n");
> @@ -740,6 +746,8 @@ static int __devinit sdhci_s3c_probe(struct platform_device *pdev)
>  
>   err_add_host:
>  	release_resource(sc->ioarea);
> +	pm_runtime_forbid(&pdev->dev);
> +	pm_runtime_get_noresume(&pdev->dev);
>  	kfree(sc->ioarea);
>  
>   err_req_regs:
> @@ -784,6 +792,8 @@ static int __devexit sdhci_s3c_remove(struct platform_device *pdev)
>  
>  	sdhci_remove_host(host, 1);
>  
> +	pm_runtime_disable(&pdev->dev);
> +
>  	for (ptr = 0; ptr < 3; ptr++) {
>  		if (sc->clk_bus[ptr]) {
>  			clk_disable(sc->clk_bus[ptr]);
> @@ -824,9 +834,27 @@ static int sdhci_s3c_resume(struct device *dev)
>  }
>  #endif
>  
> +#ifdef CONFIG_PM_RUNTIME
> +static int sdhci_s3c_runtime_suspend(struct device *dev)
> +{
> +	struct sdhci_host *host = dev_get_drvdata(dev);
> +
> +	return sdhci_runtime_suspend_host(host);
> +}
> +
> +static int sdhci_s3c_runtime_resume(struct device *dev)
> +{
> +	struct sdhci_host *host = dev_get_drvdata(dev);
> +
> +	return sdhci_runtime_resume_host(host);
> +}
> +#endif
> +
>  #ifdef CONFIG_PM
>  static const struct dev_pm_ops sdhci_s3c_pmops = {
>  	SET_SYSTEM_SLEEP_PM_OPS(sdhci_s3c_suspend, sdhci_s3c_resume)
> +	SET_RUNTIME_PM_OPS(sdhci_s3c_runtime_suspend, sdhci_s3c_runtime_resume,
> +			   NULL)
>  };
>  
>  #define SDHCI_S3C_PMOPS (&sdhci_s3c_pmops)