diff mbox

[2/8] mmc: sdhci-pxav3: disable clock inversion for HS MMC cards

Message ID 1444094562-31165-3-git-send-email-mw@semihalf.com (mailing list archive)
State New, archived
Headers show

Commit Message

Marcin Wojtas Oct. 6, 2015, 1:22 a.m. UTC 
From: Nadav Haklai <nadavh@marvell.com>

According to 'FE-2946959' erratum the clock inversion option is
needed to support slow frequencies when the card input hold time
requirement is high. This setting is not required for high speed
MMC and might cause timing violation.

Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Cc: <stable@vger.kernel.org> # v4.2
---
 drivers/mmc/host/sdhci-pxav3.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Gregory CLEMENT Oct. 6, 2015, 2:44 p.m. UTC | #1 
Hi Marcin,
 
 On mar., oct. 06 2015, Marcin Wojtas <mw@semihalf.com> wrote:

> From: Nadav Haklai <nadavh@marvell.com>
>
> According to 'FE-2946959' erratum the clock inversion option is
> needed to support slow frequencies when the card input hold time
> requirement is high. This setting is not required for high speed
> MMC and might cause timing violation.
>
> Signed-off-by: Nadav Haklai <nadavh@marvell.com>
> Cc: <stable@vger.kernel.org> # v4.2

Seems OK too.

Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

Thanks,

Gregory
> ---
>  drivers/mmc/host/sdhci-pxav3.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c
> index 976cddd..89a9e49 100644
> --- a/drivers/mmc/host/sdhci-pxav3.c
> +++ b/drivers/mmc/host/sdhci-pxav3.c
> @@ -291,6 +291,9 @@ static void pxav3_set_uhs_signaling(struct sdhci_host *host, unsigned int uhs)
>  		    uhs == MMC_TIMING_UHS_DDR50) {
>  			reg_val &= ~SDIO3_CONF_CLK_INV;
>  			reg_val |= SDIO3_CONF_SD_FB_CLK;
> +		} else if (uhs == MMC_TIMING_MMC_HS) {
> +			reg_val &= ~SDIO3_CONF_CLK_INV;
> +			reg_val &= ~SDIO3_CONF_SD_FB_CLK;
>  		} else {
>  			reg_val |= SDIO3_CONF_CLK_INV;
>  			reg_val &= ~SDIO3_CONF_SD_FB_CLK;
> -- 
> 1.8.3.1
>
Ulf Hansson Oct. 8, 2015, 5:35 p.m. UTC | #2 
On 6 October 2015 at 03:22, Marcin Wojtas <mw@semihalf.com> wrote:
> From: Nadav Haklai <nadavh@marvell.com>
>
> According to 'FE-2946959' erratum the clock inversion option is
> needed to support slow frequencies when the card input hold time
> requirement is high. This setting is not required for high speed
> MMC and might cause timing violation.
>
> Signed-off-by: Nadav Haklai <nadavh@marvell.com>
> Cc: <stable@vger.kernel.org> # v4.2

Thanks, applied for fixes!

Kind regards
Uffe

> ---
>  drivers/mmc/host/sdhci-pxav3.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c
> index 976cddd..89a9e49 100644
> --- a/drivers/mmc/host/sdhci-pxav3.c
> +++ b/drivers/mmc/host/sdhci-pxav3.c
> @@ -291,6 +291,9 @@ static void pxav3_set_uhs_signaling(struct sdhci_host *host, unsigned int uhs)
>                     uhs == MMC_TIMING_UHS_DDR50) {
>                         reg_val &= ~SDIO3_CONF_CLK_INV;
>                         reg_val |= SDIO3_CONF_SD_FB_CLK;
> +               } else if (uhs == MMC_TIMING_MMC_HS) {
> +                       reg_val &= ~SDIO3_CONF_CLK_INV;
> +                       reg_val &= ~SDIO3_CONF_SD_FB_CLK;
>                 } else {
>                         reg_val |= SDIO3_CONF_CLK_INV;
>                         reg_val &= ~SDIO3_CONF_SD_FB_CLK;
> --
> 1.8.3.1
>
diff mbox

Patch

diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c
index 976cddd..89a9e49 100644
--- a/drivers/mmc/host/sdhci-pxav3.c
+++ b/drivers/mmc/host/sdhci-pxav3.c
@@ -291,6 +291,9 @@  static void pxav3_set_uhs_signaling(struct sdhci_host *host, unsigned int uhs)
 		    uhs == MMC_TIMING_UHS_DDR50) {
 			reg_val &= ~SDIO3_CONF_CLK_INV;
 			reg_val |= SDIO3_CONF_SD_FB_CLK;
+		} else if (uhs == MMC_TIMING_MMC_HS) {
+			reg_val &= ~SDIO3_CONF_CLK_INV;
+			reg_val &= ~SDIO3_CONF_SD_FB_CLK;
 		} else {
 			reg_val |= SDIO3_CONF_CLK_INV;
 			reg_val &= ~SDIO3_CONF_SD_FB_CLK;