On Thu, May 04, 2017 at 12:48:35PM +0300, Imre Deak wrote:
> 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)
>
> v5:
> - Rebase on pci/next branch using the free next enum number available.
>
> 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>
Applied this patch only to for-linus for v4.12. I'll try to remember to cc
you when I ask Linus to pull it.
> ---
>
> [ Bjorn, could you apply this one patch to the pci tree? We would merge
> the second patch via the drm-tip tree once this one shows up in Linus'
> tree. ]
> ---
> 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 b01bd5b..563901c 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -2144,7 +2144,8 @@ 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 88185ff..ce82b60 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -183,6 +183,11 @@ enum pci_dev_flags {
> PCI_DEV_FLAGS_BRIDGE_XLATE_ROOT = (__force pci_dev_flags_t) (1 << 9),
> /* Do not use FLR even if device advertises PCI_AF_CAP */
> PCI_DEV_FLAGS_NO_FLR_RESET = (__force pci_dev_flags_t) (1 << 10),
> + /*
> + * 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 {
> --
> 2.7.4
>