[U-Boot] [PATCH v2 2/4] kw_spi: backup and reset the MPP of the chosen CS pin

[Prafulla Wadaskar]

> -----Original Message-----
> From: Valentin Longchamp [mailto:valentin.longchamp at keymile.com]
> Sent: 30 May 2012 21:12
> To: Prafulla Wadaskar
> Cc: Valentin Longchamp; holger.brunck at keymile.com; u-
> boot at lists.denx.de; Prafulla Wadaskar
> Subject: [PATCH v2 2/4] kw_spi: backup and reset the MPP of the chosen
> CS pin
> 
> This was not done before, and in the case of a shared pin (for MPP0
> between NF_IO[2] and CSn) this could lead to problems.
> 
> Signed-off-by: Valentin Longchamp <valentin.longchamp at keymile.com>
> cc: Holger Brunck <holger.brunck at keymile.com>
> cc: Prafulla Wadaskar <prafulla at marvell.com>
> ---
>  drivers/spi/kirkwood_spi.c |   14 ++++++--------
>  1 files changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/spi/kirkwood_spi.c b/drivers/spi/kirkwood_spi.c
> index db8ba8b..2fd89d2 100644
> --- a/drivers/spi/kirkwood_spi.c
> +++ b/drivers/spi/kirkwood_spi.c
> @@ -34,16 +34,14 @@
> 
>  static struct kwspi_registers *spireg = (struct kwspi_registers
> *)KW_SPI_BASE;
> 
> +u32 cs_spi_mpp_back[2];
> +
>  struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
>  				unsigned int max_hz, unsigned int mode)
>  {
>  	struct spi_slave *slave;
>  	u32 data;
> -	u32 kwspi_mpp_config[] = {
> -		MPP0_GPIO,
> -		MPP7_SPI_SCn,
> -		0
> -	};
> +	u32 kwspi_mpp_config[] = { 0, 0 };
> 
>  	if (!spi_cs_is_valid(bus, cs))
>  		return NULL;
> @@ -70,12 +68,11 @@ struct spi_slave *spi_setup_slave(unsigned int
> bus, unsigned int cs,
> 
>  	/* program mpp registers to select  SPI_CSn */
>  	if (cs) {
> -		kwspi_mpp_config[0] = MPP0_GPIO;
> -		kwspi_mpp_config[1] = MPP7_SPI_SCn;
> +		kwspi_mpp_config[0] = MPP7_SPI_SCn;
>  	} else {
>  		kwspi_mpp_config[0] = MPP0_SPI_SCn;
> -		kwspi_mpp_config[1] = MPP7_GPO;
>  	}
> +	kirkwood_mpp_read(kwspi_mpp_config, cs_spi_mpp_back);
>  	kirkwood_mpp_conf(kwspi_mpp_config);
> 
>  	return slave;
> @@ -83,6 +80,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus,
> unsigned int cs,
> 
>  void spi_free_slave(struct spi_slave *slave)
>  {
> +	kirkwood_mpp_conf(cs_spi_mpp_back);
>  	free(slave);
>  }
> 
> --

Acked-By: Prafulla Wadaskar <prafulla at maravell.com>
But as you said functionality need to be verified, I hope you have verified it on any of Kirkwood variant.

Regards..
Prafulla . . .

> 1.7.1