i2c: reduce parent checking to a NOOP in non-I2C_MUX case
In 0826374 - i2c: Multiplexed I2C bus core support
core i2c code increased in size and complexity even when I2C_MUX
wasn't selected.
Turning this check into a constant NULL in the n case lets the
client functions in be simplified too, not needing to include
never-called calls to the mux-specific helpers.
Signed-off-by: Phil Carmody <phil.carmody@partner.samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index e988fa9..b3c4b8d 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -447,11 +447,13 @@
static inline struct i2c_adapter *
i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
{
+#if IS_ENABLED(I2C_MUX)
struct device *parent = adapter->dev.parent;
if (parent != NULL && parent->type == &i2c_adapter_type)
return to_i2c_adapter(parent);
else
+#endif
return NULL;
}