Re: [PATCH V5 17/26] mmc: sdhci-uhs2: add clock operations

From: Victor Shih
Date: Tue Dec 13 2022 - 03:48:23 EST


Hi, Adrian

On Wed, Nov 2, 2022 at 1:14 AM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>
> On 19/10/22 14:06, Victor Shih wrote:
> > This is a sdhci version of mmc's uhs2_[enable|disable]_clk operations.
> >
> > Signed-off-by: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
> > Signed-off-by: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>
> > ---
> > drivers/mmc/host/sdhci-uhs2.c | 36 +++++++++++++++++++++++++++++++++++
> > 1 file changed, 36 insertions(+)
> >
> > diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> > index 9ceae552c323..afaca5d96938 100644
> > --- a/drivers/mmc/host/sdhci-uhs2.c
> > +++ b/drivers/mmc/host/sdhci-uhs2.c
> > @@ -11,6 +11,7 @@
> > */
> >
> > #include <linux/delay.h>
> > +#include <linux/ktime.h>
> > #include <linux/module.h>
> >
> > #include "sdhci.h"
> > @@ -403,6 +404,37 @@ int sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> > return 0;
> > }
> >
> > +static int sdhci_uhs2_disable_clk(struct mmc_host *mmc)
> > +{
> > + struct sdhci_host *host = mmc_priv(mmc);
> > + u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > +
> > + clk &= ~SDHCI_CLOCK_CARD_EN;
> > + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > +
> > + return 0;
> > +}
> > +
> > +static int sdhci_uhs2_enable_clk(struct mmc_host *mmc)
> > +{
> > + struct sdhci_host *host = mmc_priv(mmc);
> > + u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > + u32 val;
> > + /* 20ms */
> > + int timeout_us = 20000;
> > +
> > + clk |= SDHCI_CLOCK_CARD_EN;
> > + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > +
> > + if (read_poll_timeout_atomic(sdhci_readw, val, (val & SDHCI_CLOCK_INT_STABLE),
> > + 10, timeout_us, true, host, SDHCI_CLOCK_CONTROL)) {
> > + pr_err("%s: Internal clock never stabilised.\n", mmc_hostname(host->mmc));
> > + sdhci_dumpregs(host);
> > + return 1;
> > + }
> > + return 0;
> > +}
> > +
> > /*****************************************************************************\
> > * *
> > * Driver init/exit *
> > @@ -560,6 +592,10 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
> >
> > if (!host->mmc_host_ops.uhs2_detect_init)
> > host->mmc_host_ops.uhs2_detect_init = sdhci_uhs2_do_detect_init;
> > + if (!host->mmc_host_ops.uhs2_disable_clk)
> > + host->mmc_host_ops.uhs2_disable_clk = sdhci_uhs2_disable_clk;
> > + if (!host->mmc_host_ops.uhs2_enable_clk)
> > + host->mmc_host_ops.uhs2_enable_clk = sdhci_uhs2_enable_clk;
>
> As mentioned before ->uhs2_disable_clk() and ->uhs2_enable_clk()
> are never called.
>

I will update it in the patch#16 of the new [PATCH V6].

> >
> > return 0;
> > }
>

Thanks, Victor Shih