[PATCH v2 1/6] PCI: Add helper for checking if a PCI device is a display controller

[Mario Limonciello <superm1@kernel.org>]

From: Mario Limonciello <mario.limonciello@amd.com>

Several places in the kernel do class shifting to match whether a
PCI device is display class.  Introduce a helper for those places to
use.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 include/linux/pci.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 05e68f35f3923..e77754e43c629 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -744,6 +744,21 @@ static inline bool pci_is_vga(struct pci_dev *pdev)
 	return false;
 }
 
+/**
+ * pci_is_display - Check if a PCI device is a display controller
+ * @pdev: Pointer to the PCI device structure
+ *
+ * This function determines whether the given PCI device corresponds
+ * to a display controller. Display controllers are typically used
+ * for graphical output and are identified based on their class code.
+ *
+ * Return: true if the PCI device is a display controller, false otherwise.
+ */
+static inline bool pci_is_display(struct pci_dev *pdev)
+{
+	return (pdev->class >> 16) == PCI_BASE_CLASS_DISPLAY;
+}
+
 #define for_each_pci_bridge(dev, bus)				\
 	list_for_each_entry(dev, &bus->devices, bus_list)	\
 		if (!pci_is_bridge(dev)) {} else
-- 
2.43.0