[U-Boot] [PATCH] nitrogen6x: Fix the PAD settings for the ECSPI chipselect

Eric Nelson eric.nelson at boundarydevices.com
Sat Apr 12 17:04:51 CEST 2014


Thanks Fabio,

On 04/11/2014 01:43 PM, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam at freescale.com>
>
> ECSPI chipselect (MX6_PAD_EIM_D19__GPIO3_IO19) is used with GPIO functionality,
> so it does not make sense to set its pad as SPI pin.
>

You're right, although most of the SPI pad settings won't have
any effect as soon as the pad is configured as a GPIO output:
	http://git.denx.de/?p=u-boot.git;a=blob;f=board/boundary/nitrogen6x/nitrogen6x.c;h=d9c05b07bfae83466513735cbec95c7f949de7a5;hb=HEAD#l47

> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> ---
> Eric,
>
> This is untested.
>
>   board/boundary/nitrogen6x/nitrogen6x.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/board/boundary/nitrogen6x/nitrogen6x.c b/board/boundary/nitrogen6x/nitrogen6x.c
> index d9c05b0..f2492e4 100644
> --- a/board/boundary/nitrogen6x/nitrogen6x.c
> +++ b/board/boundary/nitrogen6x/nitrogen6x.c
> @@ -331,7 +331,7 @@ int board_mmc_init(bd_t *bis)
>   #ifdef CONFIG_MXC_SPI
>   iomux_v3_cfg_t const ecspi1_pads[] = {
>   	/* SS1 */
> -	MX6_PAD_EIM_D19__GPIO3_IO19   | MUX_PAD_CTRL(SPI_PAD_CTRL),
> +	MX6_PAD_EIM_D19__GPIO3_IO19  | MUX_PAD_CTRL(NO_PAD_CTRL),
>   	MX6_PAD_EIM_D17__ECSPI1_MISO | MUX_PAD_CTRL(SPI_PAD_CTRL),
>   	MX6_PAD_EIM_D18__ECSPI1_MOSI | MUX_PAD_CTRL(SPI_PAD_CTRL),
>   	MX6_PAD_EIM_D16__ECSPI1_SCLK | MUX_PAD_CTRL(SPI_PAD_CTRL),
>

I'll test this out ASAP, but I have to ask: what made you
look at this pin's settings.

It seems that the only bit which could affect things is dropping
the drive strength setting, and 40 ohms is the power-on default.

Regards,


Eric


More information about the U-Boot mailing list