diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index bceaf70f4e23..6fdb25a5f801 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -465,7 +465,7 @@ void __i2c_dw_disable(struct dw_i2c_dev *dev)
 	dev_warn(dev->dev, "timeout in disabling adapter\n");
 }
 
-unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev)
+u32 i2c_dw_clk_rate(struct dw_i2c_dev *dev)
 {
 	/*
 	 * Clock is not necessary if we got LCNT/HCNT values directly from
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 4d3a3b464ecd..56a029da448a 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -322,7 +322,7 @@ int i2c_dw_init_regmap(struct dw_i2c_dev *dev);
 u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset);
 u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset);
 int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
-unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev);
+u32 i2c_dw_clk_rate(struct dw_i2c_dev *dev);
 int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare);
 int i2c_dw_acquire_lock(struct dw_i2c_dev *dev);
 void i2c_dw_release_lock(struct dw_i2c_dev *dev);