[PATCH v4 25/28] drm/xe/pci: Introduce a helper to allow VF access to PF xe_device

["Michał Winiarski" <michal.winiarski@intel.com>]

In certain scenarios (such as VF migration), VF driver needs to interact
with PF driver.
Add a helper to allow VF driver access to PF xe_device.

Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
---
 drivers/gpu/drm/xe/xe_pci.c | 17 +++++++++++++++++
 drivers/gpu/drm/xe/xe_pci.h |  3 +++
 2 files changed, 20 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
index 1959de3f7a27c..8b2483d1cbea0 100644
--- a/drivers/gpu/drm/xe/xe_pci.c
+++ b/drivers/gpu/drm/xe/xe_pci.c
@@ -1224,6 +1224,23 @@ static struct pci_driver xe_pci_driver = {
 #endif
 };
 
+/**
+ * xe_pci_get_pf() - Get PF &xe_device.
+ * @pdev: the VF &pci_dev device
+ *
+ * Return: pointer to PF &xe_device, NULL otherwise.
+ */
+struct xe_device *xe_pci_get_pf(struct pci_dev *pdev)
+{
+	struct drm_device *drm;
+
+	drm = pci_iov_get_pf_drvdata(pdev, &xe_pci_driver);
+	if (IS_ERR(drm))
+		return NULL;
+
+	return to_xe_device(drm);
+}
+
 int xe_register_pci_driver(void)
 {
 	return pci_register_driver(&xe_pci_driver);
diff --git a/drivers/gpu/drm/xe/xe_pci.h b/drivers/gpu/drm/xe/xe_pci.h
index 611c1209b14cc..e97800d5c9dc3 100644
--- a/drivers/gpu/drm/xe/xe_pci.h
+++ b/drivers/gpu/drm/xe/xe_pci.h
@@ -6,6 +6,9 @@
 #ifndef _XE_PCI_H_
 #define _XE_PCI_H_
 
+struct pci_dev;
+
+struct xe_device *xe_pci_get_pf(struct pci_dev *pdev);
 int xe_register_pci_driver(void);
 void xe_unregister_pci_driver(void);
 
-- 
2.51.2