[PATCH 5/5] fbcon: Remove fb_debug_enter/_leave from struct fb_ops

Thomas Zimmermann
2025-11-25T13:06:56Z

There are no implementations of fb_debug_enter and fb_debug_leave.
Remove the callbacks from struct fb_ops and clean up the caller.

The field save_graphics in fbcon_par is also no longer required.
Remove it as well.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
Documentation/process/debugging/kgdb.rst | 28 ------------------------
drivers/video/fbdev/core/fbcon.c | 24 --------------------
drivers/video/fbdev/core/fbcon.h | 1 -
include/linux/fb.h | 4 ----
4 files changed, 57 deletions(-)

diff --git a/Documentation/process/debugging/kgdb.rst b/Documentation/process/debugging/kgdb.rst
index b29b0aac2717..773b19aa1382 100644
--- a/Documentation/process/debugging/kgdb.rst
+++ b/Documentation/process/debugging/kgdb.rst
@@ -889,34 +889,6 @@ in the virtual console layer. On resuming kernel execution, the kernel
debugger calls kgdboc_post_exp_handler() which in turn calls
con_debug_leave().

-Any video driver that wants to be compatible with the kernel debugger
-and the atomic kms callbacks must implement the ``mode_set_base_atomic``,
-``fb_debug_enter`` and ``fb_debug_leave operations``. For the
-``fb_debug_enter`` and ``fb_debug_leave`` the option exists to use the
-generic drm fb helper functions or implement something custom for the
-hardware. The following example shows the initialization of the
-.mode_set_base_atomic operation in
-drivers/gpu/drm/i915/intel_display.c::
-
-
- static const struct drm_crtc_helper_funcs intel_helper_funcs = {
- [...]
- .mode_set_base_atomic = intel_pipe_set_base_atomic,
- [...]
- };
-
-
-Here is an example of how the i915 driver initializes the
-fb_debug_enter and fb_debug_leave functions to use the generic drm
-helpers in ``drivers/gpu/drm/i915/intel_fb.c``::
-
-
- static struct fb_ops intelfb_ops = {
- [...]
- .fb_debug_enter = drm_fb_helper_debug_enter,
- .fb_debug_leave = drm_fb_helper_debug_leave,
- [...]
- };

Credits
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 7be9e865325d..34ea14412ace 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -2289,28 +2289,6 @@ static bool fbcon_blank(struct vc_data *vc, enum vesa_blank_mode blank,
return false;
}

-static void fbcon_debug_enter(struct vc_data *vc)
-{
- struct fb_info *info = fbcon_info_from_console(vc->vc_num);
- struct fbcon_par *par = info->fbcon_par;
-
- par->save_graphics = par->graphics;
- par->graphics = 0;
- if (info->fbops->fb_debug_enter)
- info->fbops->fb_debug_enter(info);
- fbcon_set_palette(vc, color_table);
-}
-
-static void fbcon_debug_leave(struct vc_data *vc)
-{
- struct fb_info *info = fbcon_info_from_console(vc->vc_num);
- struct fbcon_par *par = info->fbcon_par;
-
- par->graphics = par->save_graphics;
- if (info->fbops->fb_debug_leave)
- info->fbops->fb_debug_leave(info);
-}
-
static int fbcon_get_font(struct vc_data *vc, struct console_font *font, unsigned int vpitch)
{
u8 *fontdata = vc->vc_font.data;
@@ -3214,8 +3192,6 @@ static const struct consw fb_con = {
.con_set_palette = fbcon_set_palette,
.con_invert_region = fbcon_invert_region,
.con_resize = fbcon_resize,
- .con_debug_enter = fbcon_debug_enter,
- .con_debug_leave = fbcon_debug_leave,
};

static ssize_t rotate_store(struct device *device,
diff --git a/drivers/video/fbdev/core/fbcon.h b/drivers/video/fbdev/core/fbcon.h
index 44ea4ae4bba0..1cd10a7faab0 100644
--- a/drivers/video/fbdev/core/fbcon.h
+++ b/drivers/video/fbdev/core/fbcon.h
@@ -79,7 +79,6 @@ struct fbcon_par {
int cursor_reset;
int blank_state;
int graphics;
- int save_graphics; /* for debug enter/leave */
bool initialized;
int rotate;
int cur_rotate;
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 05cc251035da..65fb70382675 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -304,10 +304,6 @@ struct fb_ops {

/* teardown any resources to do with this framebuffer */
void (*fb_destroy)(struct fb_info *info);
-
- /* called at KDB enter and leave time to prepare the console */
- int (*fb_debug_enter)(struct fb_info *info);
- int (*fb_debug_leave)(struct fb_info *info);
};

#ifdef CONFIG_FB_TILEBLITTING
--
2.51.1