[PATCH v2] fbdev: mb862xxfbdrv: Make CONFIG_FB_DEVICE optional

[Javier Garcia <rampxxxx@gmail.com>]

This patch wraps the relevant code blocks with `IS_ENABLED(ifdef CONFIG_FB_DEVICE)`,
allowing the driver to be built and used even if CONFIG_FB_DEVICE is not selected.

The sysfs only give access to show some controller and cursor registers so
it's not needed to allow driver works correctly.

This align with Documentation/drm/todo.rst
"Remove driver dependencies on FB_DEVICE"

Signed-off-by: Javier Garcia <rampxxxx@gmail.com>
---
v1 -> v2:
      * Fix error and improvement , thanks Uwe Kleine-Koenig.
      * v1 https://lore.kernel.org/lkml/20251005173812.1169436-1-rampxxxx@gmail.com


 drivers/video/fbdev/mb862xx/mb862xxfbdrv.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/video/fbdev/mb862xx/mb862xxfbdrv.c b/drivers/video/fbdev/mb862xx/mb862xxfbdrv.c
index ade88e7bc760..dc99b8c9ff0f 100644
--- a/drivers/video/fbdev/mb862xx/mb862xxfbdrv.c
+++ b/drivers/video/fbdev/mb862xx/mb862xxfbdrv.c
@@ -17,6 +17,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include "linux/kconfig.h"
 #include <linux/pci.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
@@ -759,7 +760,7 @@ static int of_platform_mb862xx_probe(struct platform_device *ofdev)
 
 	dev_set_drvdata(dev, info);
 
-	if (device_create_file(dev, &dev_attr_dispregs))
+	if (IS_ENABLED(CONFIG_FB_DEVICE) && device_create_file(dev, &dev_attr_dispregs))
 		dev_err(dev, "Can't create sysfs regdump file\n");
 	return 0;
 
@@ -801,7 +802,8 @@ static void of_platform_mb862xx_remove(struct platform_device *ofdev)
 	free_irq(par->irq, (void *)par);
 	irq_dispose_mapping(par->irq);
 
-	device_remove_file(&ofdev->dev, &dev_attr_dispregs);
+	if(IS_ENABLED(CONFIG_FB_DEVICE))
+		device_remove_file(&ofdev->dev, &dev_attr_dispregs);
 
 	unregister_framebuffer(fbi);
 	fb_dealloc_cmap(&fbi->cmap);
@@ -1101,7 +1103,7 @@ static int mb862xx_pci_probe(struct pci_dev *pdev,
 
 	pci_set_drvdata(pdev, info);
 
-	if (device_create_file(dev, &dev_attr_dispregs))
+	if (IS_ENABLED(CONFIG_FB_DEVICE) && device_create_file(dev, &dev_attr_dispregs))
 		dev_err(dev, "Can't create sysfs regdump file\n");
 
 	if (par->type == BT_CARMINE)
@@ -1151,7 +1153,8 @@ static void mb862xx_pci_remove(struct pci_dev *pdev)
 
 	mb862xx_i2c_exit(par);
 
-	device_remove_file(&pdev->dev, &dev_attr_dispregs);
+	if(IS_ENABLED(CONFIG_FB_DEVICE))
+		device_remove_file(&pdev->dev, &dev_attr_dispregs);
 
 	unregister_framebuffer(fbi);
 	fb_dealloc_cmap(&fbi->cmap);
-- 
2.50.1