From bd58904a328fe53a5b8b8f03127c98b072e0986d Mon Sep 17 00:00:00 2001
From: Tomas Winkler <tomas.winkler@intel.com>
Date: Tue, 27 Sep 2022 17:41:36 -0700
Subject: mei: pxp: support matching with a gfx discrete card
Git-commit: bd58904a328fe53a5b8b8f03127c98b072e0986d
Patch-mainline: v6.2-rc1
References: jsc#PED-1218

With on-boards graphics card, both i915 and MEI
are in the same device hierarchy with the same parent,
while for discrete gfx card the MEI is its child device.
Adjust the match function for that scenario
by matching MEI parent device with i915.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Vitaly Lubart <vitaly.lubart@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220928004145.745803-7-daniele.ceraolospurio@intel.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/misc/mei/pxp/mei_pxp.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/misc/mei/pxp/mei_pxp.c b/drivers/misc/mei/pxp/mei_pxp.c
index f221464c4009..8dd09b1722eb 100644
--- a/drivers/misc/mei/pxp/mei_pxp.c
+++ b/drivers/misc/mei/pxp/mei_pxp.c
@@ -156,17 +156,24 @@ static int mei_pxp_component_match(struct device *dev, int subcomponent,
 {
 	struct device *base = data;
 
+	if (!dev)
+		return 0;
+
 	if (!dev->driver || strcmp(dev->driver->name, "i915") ||
 	    subcomponent != I915_COMPONENT_PXP)
 		return 0;
 
 	base = base->parent;
-	if (!base)
+	if (!base) /* mei device */
 		return 0;
 
-	base = base->parent;
-	dev = dev->parent;
+	base = base->parent; /* pci device */
+	/* for dgfx */
+	if (base && dev == base)
+		return 1;
 
+	/* for pch */
+	dev = dev->parent;
 	return (base && dev && dev == base);
 }
 
-- 
2.39.0