Re: [RESEND PATCH 2/3] mmc: host: sdhci-sprd: Implement the request_atomic() API

From: Baolin Wang
Date: Mon Mar 16 2020 - 22:02:28 EST


On Mon, Mar 16, 2020 at 7:47 PM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
>
> On Wed, 4 Mar 2020 at 08:42, Baolin Wang <baolin.wang7@xxxxxxxxx> wrote:
> >
> > Implement the request_atomic() API for nonremovable cards, that means
> > we can submit next request in the irq hard handler context to reduce
> > latency.
> >
> > Signed-off-by: Baolin Wang <baolin.wang7@xxxxxxxxx>
> > ---
> > drivers/mmc/host/sdhci-sprd.c | 28 ++++++++++++++++++++++++++--
> > 1 file changed, 26 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
> > index 2ab42c5..bddf0f3 100644
> > --- a/drivers/mmc/host/sdhci-sprd.c
> > +++ b/drivers/mmc/host/sdhci-sprd.c
> > @@ -426,6 +426,27 @@ static void sdhci_sprd_request(struct mmc_host *mmc, struct mmc_request *mrq)
> > sdhci_request(mmc, mrq);
> > }
> >
> > +static void sdhci_sprd_request_atomic(struct mmc_host *mmc,
> > + struct mmc_request *mrq)
> > +{
> > + struct sdhci_host *host = mmc_priv(mmc);
> > + struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
> > +
> > + host->flags |= sprd_host->flags & SDHCI_AUTO_CMD23;
> > +
> > + /*
> > + * From version 4.10 onward, ARGUMENT2 register is also as 32-bit
> > + * block count register which doesn't support stuff bits of
> > + * CMD23 argument on Spreadtrum's sd host controller.
> > + */
> > + if (host->version >= SDHCI_SPEC_410 &&
> > + mrq->sbc && (mrq->sbc->arg & SDHCI_SPRD_ARG2_STUFF) &&
> > + (host->flags & SDHCI_AUTO_CMD23))
> > + host->flags &= ~SDHCI_AUTO_CMD23;
>
> Looks like the above code is a copy of what is done in
> sdhci_sprd_request(). Perhaps add a helper function that deals with
> this to avoid open coding?

Sure. Will do in next version. Thanks.

>
> > +
> > + sdhci_request_atomic(mmc, mrq);
> > +}
> > +
> > static int sdhci_sprd_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
> > {
> > struct sdhci_host *host = mmc_priv(mmc);
> > @@ -561,6 +582,11 @@ static int sdhci_sprd_probe(struct platform_device *pdev)
> > if (ret)
> > goto pltfm_free;
> >
> > + if (!mmc_card_is_removable(host->mmc))
> > + host->mmc_host_ops.request_atomic = sdhci_sprd_request_atomic;
> > + else
> > + host->always_defer_done = true;
> > +
> > sprd_host = TO_SPRD_HOST(host);
> > sdhci_sprd_phy_param_parse(sprd_host, pdev->dev.of_node);
> >
> > @@ -654,8 +680,6 @@ static int sdhci_sprd_probe(struct platform_device *pdev)
> > if (ret)
> > goto err_cleanup_host;
> >
> > - host->always_defer_done = true;
> > -
> > ret = __sdhci_add_host(host);
> > if (ret)
> > goto err_cleanup_host;
> > --
> > 1.9.1
> >
>
> Kind regards
> Uffe



--
Baolin Wang