1 files changed, 9 insertions, 4 deletions

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 6e65524cbfd9..e8b5a5e21b2e 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -45,7 +45,6 @@
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/spi.h>
-#define SPI_DYN_FIRST_BUS_NUM 0
 
 static DEFINE_IDR(spi_master_idr);
 
@@ -2086,7 +2085,7 @@ int spi_register_controller(struct spi_controller *ctlr)
         struct device           *dev = ctlr->dev.parent;
         struct boardinfo        *bi;
         int                     status = -ENODEV;
-        int                     id;
+        int                     id, first_dynamic;
 
         if (!dev)
                 return -ENODEV;
@@ -2116,9 +2115,15 @@ int spi_register_controller(struct spi_controller *ctlr)
                 }
         }
         if (ctlr->bus_num < 0) {
+                first_dynamic = of_alias_get_highest_id("spi");
+                if (first_dynamic < 0)
+                        first_dynamic = 0;
+                else
+                        first_dynamic++;
+
                 mutex_lock(&board_lock);
-                id = idr_alloc(&spi_master_idr, ctlr, SPI_DYN_FIRST_BUS_NUM, 0,
-                               GFP_KERNEL);
+                id = idr_alloc(&spi_master_idr, ctlr, first_dynamic,
+                               0, GFP_KERNEL);
                 mutex_unlock(&board_lock);
                 if (WARN(id < 0, "couldn't get idr"))
                         return id;