i2c: Not all adapters have a parent

The code in acpi_i2c_register_devices() assumes that all i2c adapters
have a parent. This is not necessarily the case, for example the
i2c-stub driver instantiate a virtual i2c adapter without a parent.
Check for this to avoid a NULL pointer deference.

Signed-off-by: Jean Delvare <[email protected]>
Acked-by: Mika Westerberg <[email protected]>
Signed-off-by: Wolfram Sang <[email protected]>

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 29d3f045a2bfbc688beeb79f888cb72d10c3bcd2..3be58f89ac774962db749fcdea5c032e28edce0d 100644 (file)
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1134,6 +1134,9 @@ static void acpi_i2c_register_devices(struct i2c_adapter *adap)
        acpi_handle handle;
        acpi_status status;
 
+       if (!adap->dev.parent)
+               return;
+
        handle = ACPI_HANDLE(adap->dev.parent);
        if (!handle)
                return;