ACPI / I2C: Use parent's ACPI_HANDLE() in acpi_i2c_register_devices()

The ACPI handle of struct i2c_adapter's dev member should not be
set, because this causes that struct i2c_adapter to be associated
with the ACPI device node corresponding to its parent as the
second "physical_device", which is incorrect (this happens during
the registration of struct i2c_adapter).  Consequently,
acpi_i2c_register_devices() should use the ACPI handle of the
parent of the struct i2c_adapter it is called for rather than the
struct i2c_adapter's ACPI handle (which should be NULL).

Make that happen and modify the i2c-designware-platdrv driver,
which currently is the only driver for ACPI-enumerated I2C
controller chips, not to set the ACPI handle for the
struct i2c_adapter it creates.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>

drivers/acpi/acpi_i2c.c

@@ -90,7 +90,7 @@ void acpi_i2c_register_devices(struct i2c_adapter *adapter)
 	acpi_handle handle;
 	acpi_status status;
 
-	handle = ACPI_HANDLE(&adapter->dev);
+	handle = ACPI_HANDLE(adapter->dev.parent);
 	if (!handle)
 		return;
 

drivers/i2c/busses/i2c-designware-platdrv.c

@@ -182,7 +182,6 @@ static int dw_i2c_probe(struct platform_device *pdev)
 	adap->algo = &i2c_dw_algo;
 	adap->dev.parent = &pdev->dev;
 	adap->dev.of_node = pdev->dev.of_node;
-	ACPI_HANDLE_SET(&adap->dev, ACPI_HANDLE(&pdev->dev));
 
 	r = i2c_add_numbered_adapter(adap);
 	if (r) {