Revert "mmc: sdhci: Disable SD card clock before changing parameters"

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

Posted by Ulf Hansson 3 months, 2 weeks ago

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@ni.com>
Cc: stable@vger.kernel.org
Fixes: fb3bbc46c94f ("mmc: sdhci: Disable SD card clock before changing parameters")
Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Reported-by: Jonathan Liu <net147@gmail.com>
Reported-by: Salvatore Bonaccorso <carnil@debian.org>
Closes: https://bugs.debian.org/1108065
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---
 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);
-- 
2.43.0

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

Posted by Adrian Hunter 3 months, 2 weeks ago

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@ni.com>
> Cc: stable@vger.kernel.org
> Fixes: fb3bbc46c94f ("mmc: sdhci: Disable SD card clock before changing parameters")
> Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
> Reported-by: Jonathan Liu <net147@gmail.com>
> Reported-by: Salvatore Bonaccorso <carnil@debian.org>
> Closes: https://bugs.debian.org/1108065
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
>  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);

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

Posted by Ulf Hansson 3 months, 2 weeks ago

On Tue, 24 Jun 2025 at 13:30, Adrian Hunter <adrian.hunter@intel.com> 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@ni.com>
> > Cc: stable@vger.kernel.org
> > Fixes: fb3bbc46c94f ("mmc: sdhci: Disable SD card clock before changing parameters")
> > Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
> > Reported-by: Jonathan Liu <net147@gmail.com>
> > Reported-by: Salvatore Bonaccorso <carnil@debian.org>
> > Closes: https://bugs.debian.org/1108065
> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
>
> Acked-by: Adrian Hunter <adrian.hunter@intel.com>
>

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);
>