Re: [PATCH] Revert "mmc: sdhci: Disable SD card clock before changing parameters"

From: Ulf Hansson
Date: Tue Jun 24 2025 - 08:25:46 EST


On Tue, 24 Jun 2025 at 13:30, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>
> On 24/06/2025 14:09, Ulf Hansson wrote:
> > It has turned out the trying to strictly conform to the SDHCI specification
> > is causing problems. Let's revert and start over.
> >
> > This reverts commit fb3bbc46c94f261b6156ee863c1b06c84cf157dc.
> >
> > Cc: Erick Shepherd <erick.shepherd@xxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
> > Fixes: fb3bbc46c94f ("mmc: sdhci: Disable SD card clock before changing parameters")
> > Suggested-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> > Reported-by: Jonathan Liu <net147@xxxxxxxxx>
> > Reported-by: Salvatore Bonaccorso <carnil@xxxxxxxxxx>
> > Closes: https://bugs.debian.org/1108065
> > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>
> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>

Thanks, applied for fixes!

Kind regards
Uffe

> > ---
> > drivers/mmc/host/sdhci.c | 9 ++-------
> > 1 file changed, 2 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> > index 4c6c2cc93c41..3a17821efa5c 100644
> > --- a/drivers/mmc/host/sdhci.c
> > +++ b/drivers/mmc/host/sdhci.c
> > @@ -2065,15 +2065,10 @@ void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
> >
> > host->mmc->actual_clock = 0;
> >
> > - clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > - if (clk & SDHCI_CLOCK_CARD_EN)
> > - sdhci_writew(host, clk & ~SDHCI_CLOCK_CARD_EN,
> > - SDHCI_CLOCK_CONTROL);
> > + sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
> >
> > - if (clock == 0) {
> > - sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
> > + if (clock == 0)
> > return;
> > - }
> >
> > clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
> > sdhci_enable_clk(host, clk);
>