diff options
Diffstat (limited to 'drivers/spi/exynos_spi.c')
| -rw-r--r-- | drivers/spi/exynos_spi.c | 96 | 
1 files changed, 90 insertions, 6 deletions
| diff --git a/drivers/spi/exynos_spi.c b/drivers/spi/exynos_spi.c index 3e6c18f87..be60ada2b 100644 --- a/drivers/spi/exynos_spi.c +++ b/drivers/spi/exynos_spi.c @@ -20,6 +20,7 @@  #include <common.h>  #include <malloc.h>  #include <spi.h> +#include <fdtdec.h>  #include <asm/arch/clk.h>  #include <asm/arch/clock.h>  #include <asm/arch/cpu.h> @@ -28,16 +29,20 @@  #include <asm/arch-exynos/spi.h>  #include <asm/io.h> +DECLARE_GLOBAL_DATA_PTR; +  /* Information about each SPI controller */  struct spi_bus {  	enum periph_id periph_id;  	s32 frequency;		/* Default clock frequency, -1 for none */  	struct exynos_spi *regs;  	int inited;		/* 1 if this bus is ready for use */ +	int node;  };  /* A list of spi buses that we know about */  static struct spi_bus spi_bus[EXYNOS5_SPI_NUM_CONTROLLERS]; +static unsigned int bus_count;  struct exynos_spi_slave {  	struct spi_slave slave; @@ -50,7 +55,7 @@ struct exynos_spi_slave {  static struct spi_bus *spi_get_bus(unsigned dev_index)  { -	if (dev_index < EXYNOS5_SPI_NUM_CONTROLLERS) +	if (dev_index < bus_count)  		return &spi_bus[dev_index];  	debug("%s: invalid bus %d", __func__, dev_index); @@ -347,21 +352,100 @@ static inline struct exynos_spi *get_spi_base(int dev_index)  					(dev_index - 3);  } +/* + * Read the SPI config from the device tree node. + * + * @param blob  FDT blob to read from + * @param node  Node offset to read from + * @param bus   SPI bus structure to fill with information + * @return 0 if ok, or -FDT_ERR_NOTFOUND if something was missing + */ +static int spi_get_config(const void *blob, int node, struct spi_bus *bus) +{ +	bus->node = node; +	bus->regs = (struct exynos_spi *)fdtdec_get_addr(blob, node, "reg"); +	bus->periph_id = pinmux_decode_periph_id(blob, node); + +	if (bus->periph_id == PERIPH_ID_NONE) { +		debug("%s: Invalid peripheral ID %d\n", __func__, +			bus->periph_id); +		return -FDT_ERR_NOTFOUND; +	} + +	/* Use 500KHz as a suitable default */ +	bus->frequency = fdtdec_get_int(blob, node, "spi-max-frequency", +					500000); + +	return 0; +} + +/* + * Process a list of nodes, adding them to our list of SPI ports. + * + * @param blob          fdt blob + * @param node_list     list of nodes to process (any <=0 are ignored) + * @param count         number of nodes to process + * @param is_dvc        1 if these are DVC ports, 0 if standard I2C + * @return 0 if ok, -1 on error + */ +static int process_nodes(const void *blob, int node_list[], int count) +{ +	int i; + +	/* build the i2c_controllers[] for each controller */ +	for (i = 0; i < count; i++) { +		int node = node_list[i]; +		struct spi_bus *bus; + +		if (node <= 0) +			continue; + +		bus = &spi_bus[i]; +		if (spi_get_config(blob, node, bus)) { +			printf("exynos spi_init: failed to decode bus %d\n", +				i); +			return -1; +		} + +		debug("spi: controller bus %d at %p, periph_id %d\n", +		      i, bus->regs, bus->periph_id); +		bus->inited = 1; +		bus_count++; +	} + +	return 0; +} +  /* Sadly there is no error return from this function */  void spi_init(void)  { -	int i; +	int count; + +#ifdef CONFIG_OF_CONTROL +	int node_list[EXYNOS5_SPI_NUM_CONTROLLERS]; +	const void *blob = gd->fdt_blob; + +	count = fdtdec_find_aliases_for_id(blob, "spi", +			COMPAT_SAMSUNG_EXYNOS_SPI, node_list, +			EXYNOS5_SPI_NUM_CONTROLLERS); +	if (process_nodes(blob, node_list, count)) +		return; + +#else  	struct spi_bus *bus; -	for (i = 0; i < EXYNOS5_SPI_NUM_CONTROLLERS; i++) { -		bus = &spi_bus[i]; -		bus->regs = get_spi_base(i); -		bus->periph_id = PERIPH_ID_SPI0 + i; +	for (count = 0; count < EXYNOS5_SPI_NUM_CONTROLLERS; count++) { +		bus = &spi_bus[count]; +		bus->regs = get_spi_base(count); +		bus->periph_id = PERIPH_ID_SPI0 + count;  		/* Although Exynos5 supports upto 50Mhz speed,  		 * we are setting it to 10Mhz for safe side  		 */  		bus->frequency = 10000000;  		bus->inited = 1; +		bus->node = 0; +		bus_count = EXYNOS5_SPI_NUM_CONTROLLERS;  	} +#endif  } |