[PATCH 3/8] firmware/sysfb: Set firmware-framebuffer parent device

[Thomas Zimmermann <tzimmermann@xxxxxxx>]

Set the firmware framebuffer's parent device, which usually is the
graphics hardware's physical device. Integrates the framebuffer in
the Linux device hierarchy and lets Linux handle dependencies among
devices. For example, the graphics hardware won't be suspended while
the firmware device is still active.

Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
 drivers/firmware/sysfb.c          | 11 ++++++++++-
 drivers/firmware/sysfb_simplefb.c |  5 ++++-
 include/linux/sysfb.h             |  3 ++-
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c
index 19706bd2642a..8a42da3f67a9 100644
--- a/drivers/firmware/sysfb.c
+++ b/drivers/firmware/sysfb.c
@@ -29,6 +29,7 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
+#include <linux/pci.h>
 #include <linux/platform_data/simplefb.h>
 #include <linux/platform_device.h>
 #include <linux/screen_info.h>
@@ -72,6 +73,8 @@ EXPORT_SYMBOL_GPL(sysfb_disable);
 static __init int sysfb_init(void)
 {
 	const struct screen_info *si = &screen_info;
+	struct device *parent = NULL;
+	struct pci_dev *pparent;
 	struct simplefb_platform_data mode;
 	const char *name;
 	bool compatible;
@@ -83,10 +86,14 @@ static __init int sysfb_init(void)
 
 	sysfb_apply_efi_quirks();
 
+	pparent = screen_info_pci_dev(si);
+	if (pparent)
+		parent = &pparent->dev;
+
 	/* try to create a simple-framebuffer device */
 	compatible = sysfb_parse_mode(si, &mode);
 	if (compatible) {
-		pd = sysfb_create_simplefb(si, &mode);
+		pd = sysfb_create_simplefb(si, &mode, parent);
 		if (!IS_ERR(pd))
 			goto unlock_mutex;
 	}
@@ -109,6 +116,8 @@ static __init int sysfb_init(void)
 		goto unlock_mutex;
 	}
 
+	pd->dev.parent = parent;
+
 	sysfb_set_efifb_fwnode(pd);
 
 	ret = platform_device_add_data(pd, si, sizeof(*si));
diff --git a/drivers/firmware/sysfb_simplefb.c b/drivers/firmware/sysfb_simplefb.c
index 74363ed7501f..75a186bf8f8e 100644
--- a/drivers/firmware/sysfb_simplefb.c
+++ b/drivers/firmware/sysfb_simplefb.c
@@ -91,7 +91,8 @@ __init bool sysfb_parse_mode(const struct screen_info *si,
 }
 
 __init struct platform_device *sysfb_create_simplefb(const struct screen_info *si,
-						     const struct simplefb_platform_data *mode)
+						     const struct simplefb_platform_data *mode,
+						     struct device *parent)
 {
 	struct platform_device *pd;
 	struct resource res;
@@ -143,6 +144,8 @@ __init struct platform_device *sysfb_create_simplefb(const struct screen_info *s
 	if (!pd)
 		return ERR_PTR(-ENOMEM);
 
+	pd->dev.parent = parent;
+
 	sysfb_set_efifb_fwnode(pd);
 
 	ret = platform_device_add_resources(pd, &res, 1);
diff --git a/include/linux/sysfb.h b/include/linux/sysfb.h
index 19cb803dd5ec..6ee3ade3f8b0 100644
--- a/include/linux/sysfb.h
+++ b/include/linux/sysfb.h
@@ -91,7 +91,8 @@ static inline void sysfb_set_efifb_fwnode(struct platform_device *pd)
 bool sysfb_parse_mode(const struct screen_info *si,
 		      struct simplefb_platform_data *mode);
 struct platform_device *sysfb_create_simplefb(const struct screen_info *si,
-					      const struct simplefb_platform_data *mode);
+					      const struct simplefb_platform_data *mode,
+					      struct device *parent);
 
 #else /* CONFIG_SYSFB_SIMPLE */
 
-- 
2.43.0