RE: [PATCH V1] mmc: tegra: add sdhci tegra suspend and resume

[Sowjanya Komatineni]

> On Mon, Apr 01, 2019 at 10:27:33PM -0700, Sowjanya Komatineni wrote:
> > This patch adds suspend and resume PM ops for tegra SDHCI.
> > 
> > Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
> > ---
> >  drivers/mmc/host/sdhci-tegra.c | 45 
> > +++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 44 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/mmc/host/sdhci-tegra.c 
> > b/drivers/mmc/host/sdhci-tegra.c index eafaaefab4a6..68263ea4a93e 
> > 100644
> > --- a/drivers/mmc/host/sdhci-tegra.c
> > +++ b/drivers/mmc/host/sdhci-tegra.c
> > @@ -1611,11 +1611,54 @@ static int sdhci_tegra_remove(struct platform_device *pdev)
> >  	return 0;
> >  }
> >  
> > +#ifdef CONFIG_PM_SLEEP
> > +static int sdhci_tegra_suspend(struct device *dev) {
> > +	struct sdhci_host *host = dev_get_drvdata(dev);
> > +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(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;
> > +
> > +	clk_disable_unprepare(pltfm_host->clk);
> > +	return 0;
> > +}
> > +
> > +static int sdhci_tegra_resume(struct device *dev) {
> > +	struct sdhci_host *host = dev_get_drvdata(dev);
> > +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > +	int ret;
> > +
> > +	clk_prepare_enable(pltfm_host->clk);
>
> You need to check this for errors here.
>
> > +
> > +	ret = sdhci_resume_host(host);
> > +	if (ret)
> > +		return ret;
>
> And clk_disable_unprepare() in case of failure.
>
> > +
> > +	if (host->mmc->caps2 & MMC_CAP2_CQE)
> > +		return cqhci_resume(host->mmc);
>
> Same here. Also make sure to sdhci_suspend_host() if cqhci_resume() fails. It's probably best to have a standard error cleanup path for this.
>
> Thierry

Thanks Thierry. Will add error check and cleanup for clock and sdhci_resume_host.
Regarding, cqhci_resume always returns 0. Infact, it does nothing as resume happens on first cqhci_request.
Since helper functions exists in cqhci driver, was using it for explicit resume call.