spi_flash: Add spi_flash_probe_fdt() to locate SPI by FDT node

This allows us to put the SPI flash chip inside the SPI interface node,
with U-Boot finding the correct bus and chip select automatically.

Signed-off-by: Simon Glass <sjg@chromium.org>

2 files changed, 24 insertions, 5 deletions

diff --git a/drivers/spi/exynos_spi.c b/drivers/spi/exynos_spi.c
index 699c57eb6d..4d5def2d31 100644
--- a/drivers/spi/exynos_spi.c
+++ b/drivers/spi/exynos_spi.c
@@ -529,18 +529,18 @@ static int process_nodes(const void *blob, int node_list[], int count)
  * @param node		SPI peripheral node to use
  * @return 0 if ok, -1 on error
  */
-struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
-		unsigned int cs, unsigned int max_hz, unsigned int mode)
+struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node,
+				      int spi_node)
 {
 	struct spi_bus *bus;
 	unsigned int i;
 
 	for (i = 0, bus = spi_bus; i < bus_count; i++, bus++) {
-		if (bus->node == node)
-			return spi_setup_slave(i, cs, max_hz, mode);
+		if (bus->node == spi_node)
+			return spi_base_setup_slave_fdt(blob, i, slave_node);
 	}
 
-	debug("%s: Failed to find bus node %d\n", __func__, node);
+	debug("%s: Failed to find bus node %d\n", __func__, spi_node);
 	return NULL;
 }
 
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index b76a26cef0..7ddea9b026 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -5,6 +5,7 @@
  */
 
 #include <common.h>
+#include <fdtdec.h>
 #include <malloc.h>
 #include <spi.h>
 
@@ -37,3 +38,21 @@ void *spi_do_alloc_slave(int offset, int size, unsigned int bus,
 
 	return ptr;
 }
+
+#ifdef CONFIG_OF_SPI
+struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum,
+					   int node)
+{
+	int cs, max_hz, mode = 0;
+
+	cs = fdtdec_get_int(blob, node, "reg", -1);
+	max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 100000);
+	if (fdtdec_get_bool(blob, node, "spi-cpol"))
+		mode |= SPI_CPOL;
+	if (fdtdec_get_bool(blob, node, "spi-cpha"))
+		mode |= SPI_CPHA;
+	if (fdtdec_get_bool(blob, node, "spi-cs-high"))
+		mode |= SPI_CS_HIGH;
+	return spi_setup_slave(busnum, cs, max_hz, mode);
+}
+#endif