[U-Boot] [PATCH v2 06/13] spi: add common fdt SPI driver interface

[Stephen Warren <swarren@wwwdotorg.org>]

On 03/16/2013 10:58 PM, Allen Martin wrote:
> Add a common interface to fdt based SPI drivers.  Each driver is
> represented by a table entry in fdt_spi_drivers[].  If there are
> multiple SPI drivers in the table, the first driver to return success
> from spi_init() will be registered as the SPI driver.

> diff --git a/drivers/spi/fdt_spi.c b/drivers/spi/fdt_spi.c

> +static struct fdt_spi_driver fdt_spi_drivers[] = {
> +#ifdef CONFIG_TEGRA20_SFLASH
> +	{
> +		.compat		= COMPAT_NVIDIA_TEGRA20_SFLASH,
> +		.max_ctrls	= 1,
> +		.init		= tegra20_spi_init,
> +		.claim_bus	= tegra20_spi_claim_bus,
> +		.cs_is_valid	= tegra20_spi_cs_is_valid,
> +		.setup_slave	= tegra20_spi_setup_slave,
> +		.free_slave	= tegra20_spi_free_slave,
> +		.cs_activate	= tegra20_spi_cs_activate,
> +		.cs_deactivate	= tegra20_spi_cs_deactivate,
> +		.xfer		= tegra20_spi_xfer,
> +	},
> +#endif
> +#ifdef CONFIG_TEGRA20_SLINK
> +	{
> +		.compat		= COMPAT_NVIDIA_TEGRA20_SLINK,
> +		.max_ctrls	= CONFIG_TEGRA_SLINK_CTRLS,
> +		.init		= tegra30_spi_init,
> +		.claim_bus	= tegra30_spi_claim_bus,
> +		.cs_is_valid	= tegra30_spi_cs_is_valid,
> +		.setup_slave	= tegra30_spi_setup_slave,
> +		.free_slave	= tegra30_spi_free_slave,
> +		.cs_activate	= tegra30_spi_cs_activate,
> +		.cs_deactivate	= tegra30_spi_cs_deactivate,
> +		.xfer		= tegra30_spi_xfer,
> +	},
> +#endif
> +};

In the future, it would be nice if we could build up that table
automatically, with each driver providing its own struct inside the
driver file, and using e.g. linker scripts to piece together the structs
into one large table. That would avoid the need to list each one here,
and to prototype all those functions in a header file.

It'd also be nice to allow multiple driver to be active at once.

Still, that's certainly all something that's quite suitable for
follow-on patches later; not something that needs to be addressed in
this series.