[PATCH v2 34/38] fbdev/core: Add fb_device_{create,destroy}()

From: Thomas Zimmermann
Date: Mon Jun 12 2023 - 10:16:32 EST


Move the logic to create and destroy fbdev devices into the new
helpers fb_device_create() and fb_device_destroy().

There was a call to fb_cleanup_device() in do_unregister_framebuffer()
that was too late. The device had already been removed at this point.
Move the call into fb_device_destroy().

Declare the helpers in the new internal header file fb_internal.h, as
they are only used within the fbdev core module.

Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
drivers/video/fbdev/core/fb_internal.h | 12 ++++++++
drivers/video/fbdev/core/fbmem.c | 21 +++-----------
drivers/video/fbdev/core/fbsysfs.c | 38 ++++++++++++++++++++++++--
include/linux/fb.h | 3 --
4 files changed, 52 insertions(+), 22 deletions(-)
create mode 100644 drivers/video/fbdev/core/fb_internal.h

diff --git a/drivers/video/fbdev/core/fb_internal.h b/drivers/video/fbdev/core/fb_internal.h
new file mode 100644
index 0000000000000..0b9640ae7a3d2
--- /dev/null
+++ b/drivers/video/fbdev/core/fb_internal.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _FB_INTERNAL_H
+#define _FB_INTERNAL_H
+
+struct fb_info;
+
+/* fbsysfs.c */
+int fb_device_create(struct fb_info *fb_info);
+void fb_device_destroy(struct fb_info *fb_info);
+
+#endif
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index f91ae7d4c94d6..66532774d351e 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -40,6 +40,8 @@
#include <video/nomodeset.h>
#include <video/vga.h>

+#include "fb_internal.h"
+
/*
* Frame buffer device initialization and setup routines
*/
@@ -1447,14 +1449,7 @@ static int do_register_framebuffer(struct fb_info *fb_info)
mutex_init(&fb_info->lock);
mutex_init(&fb_info->mm_lock);

- fb_info->dev = device_create(fb_class, fb_info->device,
- MKDEV(FB_MAJOR, i), NULL, "fb%d", i);
- if (IS_ERR(fb_info->dev)) {
- /* Not fatal */
- printk(KERN_WARNING "Unable to create device for framebuffer %d; errno = %ld\n", i, PTR_ERR(fb_info->dev));
- fb_info->dev = NULL;
- } else
- fb_init_device(fb_info);
+ fb_device_create(fb_info);

if (fb_info->pixmap.addr == NULL) {
fb_info->pixmap.addr = kmalloc(FBPIXMAPSIZE, GFP_KERNEL);
@@ -1515,16 +1510,9 @@ static void unlink_framebuffer(struct fb_info *fb_info)
if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
return;

- if (!fb_info->dev)
- return;
-
- device_destroy(fb_class, MKDEV(FB_MAJOR, i));
-
+ fb_device_destroy(fb_info);
pm_vt_switch_unregister(fb_info->device);
-
unbind_console(fb_info);
-
- fb_info->dev = NULL;
}

static void do_unregister_framebuffer(struct fb_info *fb_info)
@@ -1539,7 +1527,6 @@ static void do_unregister_framebuffer(struct fb_info *fb_info)
fb_destroy_modelist(&fb_info->modelist);
registered_fb[fb_info->node] = NULL;
num_registered_fb--;
- fb_cleanup_device(fb_info);
#ifdef CONFIG_GUMSTIX_AM200EPD
{
struct fb_event event;
diff --git a/drivers/video/fbdev/core/fbsysfs.c b/drivers/video/fbdev/core/fbsysfs.c
index 849073f1ca067..fafe574398b01 100644
--- a/drivers/video/fbdev/core/fbsysfs.c
+++ b/drivers/video/fbdev/core/fbsysfs.c
@@ -8,6 +8,9 @@
#include <linux/console.h>
#include <linux/fb.h>
#include <linux/fbcon.h>
+#include <linux/major.h>
+
+#include "fb_internal.h"

#define FB_SYSFS_FLAG_ATTR 1

@@ -435,7 +438,7 @@ static struct device_attribute device_attrs[] = {
#endif
};

-int fb_init_device(struct fb_info *fb_info)
+static int fb_init_device(struct fb_info *fb_info)
{
int i, error = 0;

@@ -459,7 +462,7 @@ int fb_init_device(struct fb_info *fb_info)
return 0;
}

-void fb_cleanup_device(struct fb_info *fb_info)
+static void fb_cleanup_device(struct fb_info *fb_info)
{
unsigned int i;

@@ -470,3 +473,34 @@ void fb_cleanup_device(struct fb_info *fb_info)
fb_info->class_flag &= ~FB_SYSFS_FLAG_ATTR;
}
}
+
+int fb_device_create(struct fb_info *fb_info)
+{
+ int node = fb_info->node;
+ dev_t devt = MKDEV(FB_MAJOR, node);
+ int ret;
+
+ fb_info->dev = device_create(fb_class, fb_info->device, devt, NULL, "fb%d", node);
+ if (IS_ERR(fb_info->dev)) {
+ /* Not fatal */
+ ret = PTR_ERR(fb_info->dev);
+ pr_warn("Unable to create device for framebuffer %d; error %d\n", node, ret);
+ fb_info->dev = NULL;
+ } else {
+ fb_init_device(fb_info);
+ }
+
+ return 0;
+}
+
+void fb_device_destroy(struct fb_info *fb_info)
+{
+ dev_t devt = MKDEV(FB_MAJOR, fb_info->node);
+
+ if (!fb_info->dev)
+ return;
+
+ fb_cleanup_device(fb_info);
+ device_destroy(fb_class, devt);
+ fb_info->dev = NULL;
+}
diff --git a/include/linux/fb.h b/include/linux/fb.h
index ce6823e157e6b..1988d11f78bcb 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -735,11 +735,8 @@ static inline bool fb_be_math(struct fb_info *info)
#endif /* CONFIG_FB_FOREIGN_ENDIAN */
}

-/* drivers/video/fbsysfs.c */
extern struct fb_info *framebuffer_alloc(size_t size, struct device *dev);
extern void framebuffer_release(struct fb_info *info);
-extern int fb_init_device(struct fb_info *fb_info);
-extern void fb_cleanup_device(struct fb_info *head);
extern void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max);

/* drivers/video/fbmon.c */
--
2.41.0