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

[Benoît Thébaudeau]

Hi Otavio,

On Thursday, October 3, 2013 1:46:00 PM, 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>
> ---
>  arch/arm/include/asm/imx-common/iomux-v3.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/include/asm/imx-common/iomux-v3.h
> b/arch/arm/include/asm/imx-common/iomux-v3.h
> index dc2b3ef..b7bdaa5 100644
> --- a/arch/arm/include/asm/imx-common/iomux-v3.h
> +++ b/arch/arm/include/asm/imx-common/iomux-v3.h
> @@ -57,6 +57,7 @@ typedef u64 iomux_v3_cfg_t;
>  	MUX_SEL_INPUT_OFS_SHIFT)
>  
>  #define MUX_MODE_SHIFT		36
> +#define MUX_MODE_SION		((iomux_v3_cfg_t)IOMUX_CONFIG_SION << MUX_MODE_SHIFT)
>  #define MUX_MODE_MASK		((iomux_v3_cfg_t)0x1f << MUX_MODE_SHIFT)
>  #define MUX_PAD_CTRL_SHIFT	41
>  #define MUX_PAD_CTRL_MASK	((iomux_v3_cfg_t)0x3ffff << MUX_PAD_CTRL_SHIFT)

Looks good. Just some nit picking:
 - The line seems to be longer that the max allowed 80 chars.
 - You could perhaps move this definition to the line right above
"#define MUX_PAD_CTRL(x)" so that macros for configuration options are grouped
together.

Best regards,
Benoît