Patch "PCI/PM: Add needs_resume flag to avoid suspend complete optimization" has been added to the 4.4-stable tree

Patch "PCI/PM: Add needs_resume flag to avoid suspend complete optimization" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    PCI/PM: Add needs_resume flag to avoid suspend complete optimization

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     pci-pm-add-needs_resume-flag-to-avoid-suspend-complete-optimization.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 4d071c3238987325b9e50e33051a40d1cce311cc Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak@intel.com>
Date: Tue, 23 May 2017 14:18:17 -0500
Subject: PCI/PM: Add needs_resume flag to avoid suspend complete optimization

From: Imre Deak <imre.deak@intel.com>

commit 4d071c3238987325b9e50e33051a40d1cce311cc upstream.

Some drivers - like i915 - may not support the system suspend direct
complete optimization due to differences in their runtime and system
suspend sequence.  Add a flag that when set resumes the device before
calling the driver's system suspend handlers which effectively disables
the optimization.

Needed by a future patch fixing suspend/resume on i915.

Suggested by Rafael.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/pci/pci.c   |    3 ++-
 include/linux/pci.h |    5 +++++
 2 files changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2079,7 +2079,8 @@ bool pci_dev_keep_suspended(struct pci_d
 
 	if (!pm_runtime_suspended(dev)
 	    || pci_target_state(pci_dev) != pci_dev->current_state
-	    || platform_pci_need_resume(pci_dev))
+	    || platform_pci_need_resume(pci_dev)
+	    || (pci_dev->dev_flags & PCI_DEV_FLAGS_NEEDS_RESUME))
 		return false;
 
 	/*
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -182,6 +182,11 @@ enum pci_dev_flags {
 	PCI_DEV_FLAGS_NO_PM_RESET = (__force pci_dev_flags_t) (1 << 7),
 	/* Get VPD from function 0 VPD */
 	PCI_DEV_FLAGS_VPD_REF_F0 = (__force pci_dev_flags_t) (1 << 8),
+	/*
+	 * Resume before calling the driver's system suspend hooks, disabling
+	 * the direct_complete optimization.
+	 */
+	PCI_DEV_FLAGS_NEEDS_RESUME = (__force pci_dev_flags_t) (1 << 11),
 };
 
 enum pci_irq_reroute_variant {


Patches currently in stable-queue which might be from imre.deak@intel.com are

queue-4.4/pci-pm-add-needs_resume-flag-to-avoid-suspend-complete-optimization.patch