SPI: EXYNOS: Add FDT support to driver.

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>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>

diff --git a/drivers/spi/exynos_spi.c b/drivers/spi/exynos_spi.c
index 3e6c18f..be60ada 100644 (file)
--- 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
 }