This patch adds FDT support to the SPI driver.
Signed-off-by: Simon Glass sjg@chromium.org Signed-off-by: Rajeshwari Shinde rajeshwari.s@samsung.com Acked-by: Simon Glass sjg@chromium.org --- Changes since V1: - Corrected compilation error for non DT and removed extra blank line. 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 3e6c18f..be60ada 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 }