| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.8 109/138] drm/nouveau/acpi: fix check for power resources support | Date | Wed, 9 Nov 2016 11:46:32 +0100 |
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4.8-stable review patch. If anyone has any objections, please let me know.
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From: Peter Wu <peter@lekensteyn.nl>
commit b0a6af8b34c9ad20894aa46f85f4bf59d444f286 upstream.
Check whether the kernel really supports power resources for a device, otherwise the power might not be removed when the device is runtime suspended (DSM should still work in these cases where PR does not).
This is a workaround for a problem where ACPICA and Windows 10 differ in behavior. ACPICA does not correctly enumerate power resources within a conditional block (due to delayed execution of such blocks) and as a result power_resources is set to false even if _PR3 exists.
Fixes: 692a17dcc292 ("drm/nouveau/acpi: fix lockup with PCIe runtime PM") Link: https://bugs.freedesktop.org/show_bug.cgi?id=98398 Reported-and-tested-by: Rick Kerkhof <rick.2889@gmail.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Peter Wu <peter@lekensteyn.nl> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/gpu/drm/nouveau/nouveau_acpi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/nouveau/nouveau_acpi.c +++ b/drivers/gpu/drm/nouveau/nouveau_acpi.c @@ -240,7 +240,8 @@ static bool nouveau_pr3_present(struct p if (!parent_adev) return false; - return acpi_has_method(parent_adev->handle, "_PR3"); + return parent_adev->power.flags.power_resources && + acpi_has_method(parent_adev->handle, "_PR3"); } static void nouveau_dsm_pci_probe(struct pci_dev *pdev, acpi_handle *dhandle_out,
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