diff options
Diffstat (limited to 'drivers/spi/fdt_spi.c')
| -rw-r--r-- | drivers/spi/fdt_spi.c | 171 | 
1 files changed, 171 insertions, 0 deletions
| diff --git a/drivers/spi/fdt_spi.c b/drivers/spi/fdt_spi.c new file mode 100644 index 000000000..c6ae719d6 --- /dev/null +++ b/drivers/spi/fdt_spi.c @@ -0,0 +1,171 @@ +/* + * Common fdt based SPI driver front end + * + * Copyright (c) 2013 NVIDIA Corporation + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <malloc.h> +#include <asm/io.h> +#include <asm/gpio.h> +#include <asm/arch/clock.h> +#include <asm/arch-tegra/clk_rst.h> +#include <asm/arch-tegra20/tegra20_sflash.h> +#include <asm/arch-tegra20/tegra20_slink.h> +#include <spi.h> +#include <fdtdec.h> + +DECLARE_GLOBAL_DATA_PTR; + +struct fdt_spi_driver { +	int compat; +	int max_ctrls; +	int (*init)(int *node_list, int count); +	int (*claim_bus)(struct spi_slave *slave); +	int (*release_bus)(struct spi_slave *slave); +	int (*cs_is_valid)(unsigned int bus, unsigned int cs); +	struct spi_slave *(*setup_slave)(unsigned int bus, unsigned int cs, +					unsigned int max_hz, unsigned int mode); +	void (*free_slave)(struct spi_slave *slave); +	void (*cs_activate)(struct spi_slave *slave); +	void (*cs_deactivate)(struct spi_slave *slave); +	int (*xfer)(struct spi_slave *slave, unsigned int bitlen, +		    const void *data_out, void *data_in, unsigned long flags); +}; + +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 +}; + +static struct fdt_spi_driver *driver; + +int spi_cs_is_valid(unsigned int bus, unsigned int cs) +{ +	if (!driver) +		return 0; +	else if (!driver->cs_is_valid) +		return 1; +	else +		return driver->cs_is_valid(bus, cs); +} + +struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, +		unsigned int max_hz, unsigned int mode) +{ +	if (!driver || !driver->setup_slave) +		return NULL; + +	return driver->setup_slave(bus, cs, max_hz, mode); +} + +void spi_free_slave(struct spi_slave *slave) +{ +	if (driver && driver->free_slave) +		return driver->free_slave(slave); +} + +static int spi_init_driver(struct fdt_spi_driver *driver) +{ +	int count; +	int node_list[driver->max_ctrls]; + +	count = fdtdec_find_aliases_for_id(gd->fdt_blob, "spi", +					   driver->compat, +					   node_list, +					   driver->max_ctrls); +	return driver->init(node_list, count); +} + +void spi_init(void) +{ +	int i; + +	for (i = 0; i < ARRAY_SIZE(fdt_spi_drivers); i++) { +		driver = &fdt_spi_drivers[i]; +		if (!spi_init_driver(driver)) +			break; +	} +	if (i == ARRAY_SIZE(fdt_spi_drivers)) +		driver = NULL; +} + +int spi_claim_bus(struct spi_slave *slave) +{ +	if (!driver) +		return 1; +	if (!driver->claim_bus) +		return 0; + +	return driver->claim_bus(slave); +} + +void spi_release_bus(struct spi_slave *slave) +{ +	if (driver && driver->release_bus) +		driver->release_bus(slave); +} + +void spi_cs_activate(struct spi_slave *slave) +{ +	if (driver && driver->cs_activate) +		driver->cs_activate(slave); +} + +void spi_cs_deactivate(struct spi_slave *slave) +{ +	if (driver && driver->cs_deactivate) +		driver->cs_deactivate(slave); +} + +int spi_xfer(struct spi_slave *slave, unsigned int bitlen, +	     const void *data_out, void *data_in, unsigned long flags) +{ +	if (!driver || !driver->xfer) +		return -1; + +	return driver->xfer(slave, bitlen, data_out, data_in, flags); +} |