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 the next patch fixing suspend/resume on i915.
Suggested by Rafael.
v2-v3:
- unchanged
v4:
- Move the flag to dev_flags instead of using a bit field. (Rafael)
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: linux-pci@xxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> (v3)
---
drivers/pci/pci.c | 3 ++-
include/linux/pci.h | 5 +++++
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7904d02..a4ef755 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2141,7 +2141,8 @@ bool pci_dev_keep_suspended(struct pci_dev *pci_dev)
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;
/*
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 5948cfd..8acb560 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -178,6 +178,11 @@ 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 << 9),
};
enum pci_irq_reroute_variant {
--
2.7.4
