[PATCH v2 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.

v2:
	* detect parent device in sysfb_parent_dev()

Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
---
 drivers/firmware/sysfb.c          | 19 ++++++++++++++++++-
 drivers/firmware/sysfb_simplefb.c |  5 ++++-
 include/linux/sysfb.h             |  3 ++-
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c
index 3c197db42c9d9..d02945b0d8ea1 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>
@@ -69,9 +70,21 @@ void sysfb_disable(void)
 }
 EXPORT_SYMBOL_GPL(sysfb_disable);
 
+static __init struct device *sysfb_parent_dev(const struct screen_info *si)
+{
+	struct pci_dev *pdev;
+
+	pdev = screen_info_pci_dev(si);
+	if (pdev)
+		return &pdev->dev;
+
+	return NULL;
+}
+
 static __init int sysfb_init(void)
 {
 	struct screen_info *si = &screen_info;
+	struct device *parent;
 	struct simplefb_platform_data mode;
 	const char *name;
 	bool compatible;
@@ -83,10 +96,12 @@ static __init int sysfb_init(void)
 
 	sysfb_apply_efi_quirks();
 
+	parent = sysfb_parent_dev(si);
+
 	/* 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 +124,8 @@ 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 74363ed7501f6..75a186bf8f8ec 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 19cb803dd5ecd..6ee3ade3f8b06 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