pci_device: Add a helper function for determining if PCI device is wake source

This change adds a helper function `pci_dev_is_wake_source()` that
checks PME_STATUS and PME_ENABLE bits in PM control and status
register to determine if the given device is the source of wake.

BUG=b:169802515
BRANCH=zork

Change-Id: I06e9530b568543ab2f05a4f38dc5c3a527ff391e
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46030
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Rob Barnes <robbarnes@google.com>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/include/device/pci.h b/src/include/device/pci.h
index 6e28cb7f649a..58f5904996a8 100644
--- a/src/include/device/pci.h
+++ b/src/include/device/pci.h
@@ -80,6 +80,14 @@ void pci_bus_reset(struct bus *bus);
 struct device *pci_probe_dev(struct device *dev, struct bus *bus,
 				unsigned int devfn);
 
+/*
+ * Determine if the given PCI device is the source of wake from sleep by checking PME_STATUS and
+ * PME_ENABLE bits in PM control and status register.
+ *
+ * Returns true if PCI device is wake source, false otherwise.
+ */
+bool pci_dev_is_wake_source(const struct device *dev);
+
 void do_pci_scan_bridge(struct device *dev,
 	void (*do_scan_bus)(struct bus *bus,
 		unsigned int min_devfn, unsigned int max_devfn));