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>

3 files changed, 31 insertions, 6 deletions

diff --git a/include/configs/exynos5250-dt.h b/include/configs/exynos5250-dt.h
index bdefee1..74ba2b6 100644
--- a/include/configs/exynos5250-dt.h
+++ b/include/configs/exynos5250-dt.h
@@ -276,6 +276,7 @@
 #define CONFIG_SF_DEFAULT_MODE		SPI_MODE_0
 #define CONFIG_SF_DEFAULT_SPEED		50000000
 #define EXYNOS5_SPI_NUM_CONTROLLERS	5
+#define CONFIG_OF_SPI
 #endif
 
 #ifdef CONFIG_ENV_IS_IN_SPI_FLASH
diff --git a/include/spi.h b/include/spi.h
index e2563c9..aba7922 100644
--- a/include/spi.h
+++ b/include/spi.h
@@ -259,13 +259,24 @@ static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte)
  * spi_free_slave() to free it later.
  *
  * @param blob:		Device tree blob
- * @param node:		SPI peripheral node to use
- * @param cs:		Chip select to use
- * @param max_hz:	Maximum SCK rate in Hz (0 for default)
- * @param mode:		Clock polarity, clock phase and other parameters
+ * @param slave_node:	Slave node to use
+ * @param spi_node:	SPI peripheral node to use
  * @return pointer to new spi_slave structure
  */
-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);
+
+/**
+ * spi_base_setup_slave_fdt() - helper function to set up a SPI slace
+ *
+ * This decodes SPI properties from the slave node to determine the
+ * chip select and SPI parameters.
+ *
+ * @blob:	Device tree blob
+ * @busnum:	Bus number to use
+ * @node:	Device tree node for the SPI bus
+ */
+struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum,
+					   int node);
 
 #endif	/* _SPI_H_ */
diff --git a/include/spi_flash.h b/include/spi_flash.h
index 25ca8f1..afc3a58 100644
--- a/include/spi_flash.h
+++ b/include/spi_flash.h
@@ -67,6 +67,19 @@ struct spi_flash {
 
 struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
 		unsigned int max_hz, unsigned int spi_mode);
+
+/**
+ * Set up a new SPI flash from an fdt node
+ *
+ * @param blob		Device tree blob
+ * @param slave_node	Pointer to this SPI slave node in the device tree
+ * @param spi_node	Cached pointer to the SPI interface this node belongs
+ *			to
+ * @return 0 if ok, -1 on error
+ */
+struct spi_flash *spi_flash_probe_fdt(const void *blob, int slave_node,
+				      int spi_node);
+
 void spi_flash_free(struct spi_flash *flash);
 
 static inline int spi_flash_read(struct spi_flash *flash, u32 offset,