Commit bd0f4e34 authored Sep 23, 2018 by Hans de Goede Committed by Rafael J. Wysocki Sep 30, 2018

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>

parent 1e30124a

drivers/acpi/acpi_lpss.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -472,6 +472,7 @@ struct lpss_device_links {
		*/
		static const struct lpss_device_links lpss_device_links[] = {
		{"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
		{"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
		};

		static bool hid_uid_match(struct acpi_device *adev,

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