Re: [PATCH V4] mmc: sdhci-msm: Update system suspend/resume callbacks of sdhci-msm platform driver

[Veerabhadrarao Badiganti <vbadigan@codeaurora.org>]

Hi Sajida,

On 2/20/2020 12:15 PM, Shaik Sajida Bhanu wrote:

> 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, disabling card detection, enabling wake-up events.
>
> So updating the system pm callbacks for performing these extra
> actions besides controlling the clocks.
>
> Signed-off-by: Shaik Sajida Bhanu <sbhanu@codeaurora.org>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
> ---
> Changes since V3:
>      Invoking sdhci & cqhci resume if sdhci_host_suspend fails.
>      Removed condition check before invoking cqhci_resume since its a dummy function.
>
> Changes since V2:
>      Removed disabling/enabling pwr-irq from system pm ops.
>
> Changes since V1:
>      Invoking pm_runtime_force_suspend/resume instead of
>      sdhci_msm_runtime_suepend/resume.
> ---
>   drivers/mmc/host/sdhci-msm.c | 47 ++++++++++++++++++++++++++++++++++++++++++--
>   1 file changed, 45 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 3955fa5d..3559b50 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -2159,9 +2159,52 @@ 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);
> +	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)
> +		goto resume_cqhci;
> +
> +	ret = pm_runtime_force_suspend(dev);
> +	if (!ret)
> +		return ret;
> +
> +	sdhci_resume_host(host);
> +
> +resume_cqhci:
> +	cqhci_resume(host->mmc);
> +	return ret;
> +}
> +
> +static int sdhci_msm_resume(struct device *dev)
> +{
> +	struct sdhci_host *host = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = pm_runtime_force_resume(dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = sdhci_resume_host(host);

I'm observing an issue with this change.

After this step, i find interrupt enable register is zero (even though 
it's getting set in sdhci_resume_host()) and

resulting in request timeout for very first command in resume path.

Until its root caused, please hold back this change.

> +	if (ret < 0)
> +		return ret;
> +
> +	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)