From 4694ae373dc2114f9a82f6ae15737e65af0c6dea Mon Sep 17 00:00:00 2001 From: Konstantin Kharlamov Date: Fri, 21 May 2021 02:55:01 +0300 Subject: [PATCH] PCI: Leave Apple Thunderbolt controllers on for s2idle or standby On Macbook 2013, resuming from suspend-to-idle or standby resulted in the external monitor no longer being detected, a stacktrace, and errors like this in dmesg: pcieport 0000:06:00.0: can't change power state from D3hot to D0 (config space inaccessible) The reason is that we know how to turn power to the Thunderbolt controller *off* via the SXIO/SXFP/SXLF methods, but we don't know how to turn power back on. We have to rely on firmware to turn the power back on. When going to the "suspend-to-idle" or "standby" system sleep states, firmware is not involved either on the suspend side or the resume side, so we can't use SXIO/SXFP/SXLF to turn the power off. Skip SXIO/SXFP/SXLF when firmware isn't involved in suspend, e.g., when we're going to the "suspend-to-idle" or "standby" system sleep states. Fixes: 1df5172c5c25 ("PCI: Suspend/resume quirks for Apple thunderbolt") Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212767 Link: https://lore.kernel.org/r/20210520235501.917397-1-Hi-Angel@yandex.ru Signed-off-by: Konstantin Kharlamov Signed-off-by: Bjorn Helgaas Reviewed-by: Lukas Wunner Cc: stable@vger.kernel.org --- drivers/pci/quirks.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index dcb229d..0dde9c5 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include /* isa_dma_bridge_buggy */ #include "pci.h" @@ -3634,6 +3635,16 @@ static void quirk_apple_poweroff_thunderbolt(struct pci_dev *dev) return; if (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM) return; + + /* + * SXIO/SXFP/SXLF turns off power to the Thunderbolt controller. + * We don't know how to turn it back on again, but firmware does, + * so we can only use SXIO/SXFP/SXLF if we're suspending via + * firmware. + */ + if (!pm_suspend_via_firmware()) + return; + bridge = ACPI_HANDLE(&dev->dev); if (!bridge) return; -- 2.7.4