tree a340a36f215b7f5727857dbb20859f09207f3f4d
parent 1e30124ac60abc41d74793900f8b4034f29bcb3d
author Hans de Goede <hdegoede@redhat.com> 1537711089 +0200
committer Rafael J. Wysocki <rafael.j.wysocki@intel.com> 1538339904 +0200

ACPI / LPSS: Add a device link from the GPU to the CHT I2C7 controller

On some Cherry Trail systems the GPU ACPI fwnode has power-resources which
point to the PMIC, which is connected over the LPSS I2C7 controller.

Due to probe ordering currently we resume the GPU and thus try to access
the ACPI power-resources before the I2C controller has been resumed. This
leads to the following errors:

 i2c_designware 808622C1:06: controller timed out
 ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion]
 ACPI Error: Method parse/execution failed \_SB.P18W._ON, AE_ERROR
 video LNXVIDEO:00: Failed to change power state to D0

This commit adds a RPM consumer link from the GPU (which has a LNXVIDEO
HID) to the CHT LPSS I2C7 controller, so that the I2C controller gets
resumed before the GPU is resumed.

Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>