Re: [PATCH 01/10] mci: sdhci: define VDD_180 and shrink UHS_MASK to bits 0..2

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

On 5/11/26 2:07 PM, Sascha Hauer wrote:
> Per SDHCI 3.0+, HOST_CONTROL2's UHS Mode Select is bits 0..2 (3 bits)
> and bit 3 is the 1.8 V Signaling Enable. The current SDHCI_CTRL_UHS_MASK
> of GENMASK(3, 0) is one bit too wide and clears 1.8 V signaling every
> time sdhci_set_uhs_signaling() runs.
> 
> Shrink the mask to GENMASK(2, 0) and add SDHCI_CTRL_VDD_180 = BIT(3) so
> controllers that need to drive 1.8 V on I/O for HS200/HS400/UHS modes
> can OR the bit in without it being clobbered on the next set_clock().
> 
> No functional change for controllers where VDD_180 was unused (most
> in-tree drivers do not touch it; voltage switching there is either
> fixed by board wiring or handled by an external regulator).
> 
> Assisted-by: Claude Opus 4.7 <noreply@anthropic.com>
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>

> ---
>  drivers/mci/imx-esdhc-common.c | 2 --
>  drivers/mci/sdhci.h            | 3 ++-
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/mci/imx-esdhc-common.c b/drivers/mci/imx-esdhc-common.c
> index 050621d7fb..eb6a71915f 100644
> --- a/drivers/mci/imx-esdhc-common.c
> +++ b/drivers/mci/imx-esdhc-common.c
> @@ -12,8 +12,6 @@
>  
>  #define	ESDHC_CTRL_D3CD			0x08
>  
> -#define  SDHCI_CTRL_VDD_180         0x0008
> -
>  #define ESDHC_MIX_CTRL			0x48
>  #define  ESDHC_MIX_CTRL_DDREN		(1 << 3)
>  #define  ESDHC_MIX_CTRL_AC23EN		(1 << 7)
> diff --git a/drivers/mci/sdhci.h b/drivers/mci/sdhci.h
> index 8d21febd7a..a04eb5b7ed 100644
> --- a/drivers/mci/sdhci.h
> +++ b/drivers/mci/sdhci.h
> @@ -132,13 +132,14 @@
>  #define SDHCI_SIGNAL_ENABLE					0x38
>  #define SDHCI_ACMD12_ERR__HOST_CONTROL2				0x3C
>  #define SDHCI_HOST_CONTROL2					0x3E
> -#define  SDHCI_CTRL_UHS_MASK			GENMASK(3, 0)
> +#define  SDHCI_CTRL_UHS_MASK			GENMASK(2, 0)
>  #define   SDHCI_CTRL_UHS_SDR12			0x0
>  #define   SDHCI_CTRL_UHS_SDR25			0x1
>  #define   SDHCI_CTRL_UHS_SDR50			0x2
>  #define   SDHCI_CTRL_UHS_SDR104			0x3
>  #define   SDHCI_CTRL_UHS_DDR50			0x4
>  #define   SDHCI_CTRL_HS400			0x5 /* Non-standard */
> +#define  SDHCI_CTRL_VDD_180			BIT(3)
>  #define  SDHCI_CTRL_DRV_TYPE_MASK		GENMASK(5, 4)
>  #define   SDHCI_CTRL_DRV_TYPE_B			0x0000
>  #define   SDHCI_CTRL_DRV_TYPE_A			0x0010
> 

-- 
Pengutronix e.K.                  |                             |
Steuerwalder Str. 21              | http://www.pengutronix.de/  |
31137 Hildesheim, Germany         | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |