[PATCH v2 01/12] firmware: google: framebuffer: Do not unregister platform device

[PATCH v2 01/12] firmware: google: framebuffer: Do not unregister platform device

[Thomas Zimmermann]

The native driver takes over the framebuffer aperture by removing the
system- framebuffer platform device. Afterwards the pointer in drvdata
is dangling. Remove the entire logic around drvdata and let the kernel's
aperture helpers handle this. The platform device depends on the native
hardware device instead of the coreboot device anyway.

When commit 851b4c14532d ("firmware: coreboot: Add coreboot framebuffer
driver") added the coreboot framebuffer code, the kernel did not support
device-based aperture management. Instead native driviers only removed
the conflicting fbdev device. At that point, unregistering the framebuffer
device most likely worked correctly. It was definitely broken after
commit d9702b2a2171 ("fbdev/simplefb: Do not use struct
fb_info.apertures"). So take this commit for the Fixes tag. Earlier
releases might work depending on the native hardware driver.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: d9702b2a2171 ("fbdev/simplefb: Do not use struct fb_info.apertures")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Hans de Goede <hansg@kernel.org>
Cc: linux-fbdev@vger.kernel.org
Cc: <stable@vger.kernel.org> # v6.3+
---
 drivers/firmware/google/framebuffer-coreboot.c | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/drivers/firmware/google/framebuffer-coreboot.c b/drivers/firmware/google/framebuffer-coreboot.c
index c68c9f56370f..4e9177105992 100644
--- a/drivers/firmware/google/framebuffer-coreboot.c
+++ b/drivers/firmware/google/framebuffer-coreboot.c
@@ -81,19 +81,10 @@ static int framebuffer_probe(struct coreboot_device *dev)
 						 sizeof(pdata));
 	if (IS_ERR(pdev))
 		pr_warn("coreboot: could not register framebuffer\n");
-	else
-		dev_set_drvdata(&dev->dev, pdev);
 
 	return PTR_ERR_OR_ZERO(pdev);
 }
 
-static void framebuffer_remove(struct coreboot_device *dev)
-{
-	struct platform_device *pdev = dev_get_drvdata(&dev->dev);
-
-	platform_device_unregister(pdev);
-}
-
 static const struct coreboot_device_id framebuffer_ids[] = {
 	{ .tag = CB_TAG_FRAMEBUFFER },
 	{ /* sentinel */ }
@@ -102,7 +93,6 @@ MODULE_DEVICE_TABLE(coreboot, framebuffer_ids);
 
 static struct coreboot_driver framebuffer_driver = {
 	.probe = framebuffer_probe,
-	.remove = framebuffer_remove,
 	.drv = {
 		.name = "framebuffer",
 	},
-- 
2.52.0

Re: [PATCH v2 01/12] firmware: google: framebuffer: Do not unregister platform device

[Tzung-Bi Shih]

On Thu, Jan 15, 2026 at 08:57:11AM +0100, Thomas Zimmermann wrote:
> The native driver takes over the framebuffer aperture by removing the
> system- framebuffer platform device. Afterwards the pointer in drvdata
> is dangling. Remove the entire logic around drvdata and let the kernel's
> aperture helpers handle this. The platform device depends on the native
> hardware device instead of the coreboot device anyway.
> 
> When commit 851b4c14532d ("firmware: coreboot: Add coreboot framebuffer
> driver") added the coreboot framebuffer code, the kernel did not support
> device-based aperture management. Instead native driviers only removed
> the conflicting fbdev device. At that point, unregistering the framebuffer
> device most likely worked correctly. It was definitely broken after
> commit d9702b2a2171 ("fbdev/simplefb: Do not use struct
> fb_info.apertures"). So take this commit for the Fixes tag. Earlier
> releases might work depending on the native hardware driver.
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> Fixes: d9702b2a2171 ("fbdev/simplefb: Do not use struct fb_info.apertures")

Acked-by: Tzung-Bi Shih <tzungbi@kernel.org>