[U-Boot] [PATCH v3 3/8] imx: Easy enabling of SION per-pin using MUX_MODE_SION helper macro

Stefano Babic sbabic at denx.de
Thu Dec 19 11:40:39 CET 2013


Hi Otavio,

On 16/12/2013 23:44, Otavio Salvador wrote:
> The macro allows easy setting in per-pin, as for example:
> 
> ,----
> | imx_iomux_v3_setup_pad(MX6_PAD_NANDF_D1__GPIO_2_1 | MUX_MODE_SION);
> `----
> 
> The IOMUX_CONFIG_SION allows for reading PAD value from PSR register.
> 
> The following quote from the datasheet:
> 
> ,----
> | ...
> | 28.4.2.2 GPIO Write Mode
> | The programming sequence for driving output signals should be as follows:
> | 1. Configure IOMUX to select GPIO mode (Via IOMUXC), also enable SION if need
> | to read loopback pad value through PSR
> | 2. Configure GPIO direction register to output (GPIO_GDIR[GDIR] set to 1b).
> | 3. Write value to data register (GPIO_DR).
> | ...
> `----
> 
> This fixes the gpio_get_value to properly work when a GPIO is set for
> output and has no conflicts.
> 
> Thanks for Benoît Thébaudeau <benoit.thebaudeau at advansee.com>, Fabio
> Estevam <fabio.estevam at freescale.com> and Eric Bénard
> <eric at eukrea.com> for helping to properly trace this down.
> 
> Signed-off-by: Otavio Salvador <otavio at ossystems.com.br>
> ---
> Changes in v3: None
> Changes in v2: None
> 
>  arch/arm/include/asm/imx-common/iomux-v3.h | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/include/asm/imx-common/iomux-v3.h b/arch/arm/include/asm/imx-common/iomux-v3.h
> index dc2b3ef..dec11a1 100644
> --- a/arch/arm/include/asm/imx-common/iomux-v3.h
> +++ b/arch/arm/include/asm/imx-common/iomux-v3.h
> @@ -63,6 +63,8 @@ typedef u64 iomux_v3_cfg_t;
>  #define MUX_SEL_INPUT_SHIFT	59
>  #define MUX_SEL_INPUT_MASK	((iomux_v3_cfg_t)0xf << MUX_SEL_INPUT_SHIFT)
>  
> +#define MUX_MODE_SION		((iomux_v3_cfg_t)IOMUX_CONFIG_SION << \
> +	MUX_MODE_SHIFT)
>  #define MUX_PAD_CTRL(x)		((iomux_v3_cfg_t)(x) << MUX_PAD_CTRL_SHIFT)
>  
>  #define IOMUX_PAD(pad_ctrl_ofs, mux_ctrl_ofs, mux_mode, sel_input_ofs,	\
> 

Acked-by: Stefano Babic <sbabic at denx.de>

Best regards,
Stefano Babic

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