[PATCH 18/33] fbdev: make unregister/unlink functions not fail

[PATCH 18/33] fbdev: make unregister/unlink functions not fail

[Daniel Vetter]

Except for driver bugs (which we'll catch with a WARN_ON) this is only
to report failures of the new driver taking over the console. There's
nothing the outgoing driver can do about that, and no one ever
bothered to actually look at these return values. So remove them all.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/core/fbmem.c | 73 ++++++++++----------------------
 include/linux/fb.h               |  4 +-
 2 files changed, 25 insertions(+), 52 deletions(-)

diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 156523cc48bf..032506576aa0 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1590,13 +1590,13 @@ static bool fb_do_apertures_overlap(struct apertures_struct *gena,
 	return false;
 }
 
-static int do_unregister_framebuffer(struct fb_info *fb_info);
+static void do_unregister_framebuffer(struct fb_info *fb_info);
 
 #define VGA_FB_PHYS 0xA0000
-static int do_remove_conflicting_framebuffers(struct apertures_struct *a,
-					      const char *name, bool primary)
+static void do_remove_conflicting_framebuffers(struct apertures_struct *a,
+					       const char *name, bool primary)
 {
-	int i, ret;
+	int i;
 
 	/* check all firmware fbs and kick off if the base addr overlaps */
 	for_each_registered_fb(i) {
@@ -1612,13 +1612,9 @@ static int do_remove_conflicting_framebuffers(struct apertures_struct *a,
 
 			printk(KERN_INFO "fb%d: switching to %s from %s\n",
 			       i, name, registered_fb[i]->fix.id);
-			ret = do_unregister_framebuffer(registered_fb[i]);
-			if (ret)
-				return ret;
+			do_unregister_framebuffer(registered_fb[i]);
 		}
 	}
-
-	return 0;
 }
 
 static bool lockless_register_fb;
@@ -1634,11 +1630,9 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 	if (fb_check_foreignness(fb_info))
 		return -ENOSYS;
 
-	ret = do_remove_conflicting_framebuffers(fb_info->apertures,
-						 fb_info->fix.id,
-						 fb_is_primary_device(fb_info));
-	if (ret)
-		return ret;
+	do_remove_conflicting_framebuffers(fb_info->apertures,
+					   fb_info->fix.id,
+					   fb_is_primary_device(fb_info));
 
 	if (num_registered_fb = FB_MAX)
 		return -ENXIO;
@@ -1706,32 +1700,25 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 	return ret;
 }
 
-static int unbind_console(struct fb_info *fb_info)
+static void unbind_console(struct fb_info *fb_info)
 {
 	int i = fb_info->node;
 
-	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
-		return -EINVAL;
+	if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
+		return;
 
 	console_lock();
 	lock_fb_info(fb_info);
 	fbcon_fb_unbind(fb_info);
 	unlock_fb_info(fb_info);
 	console_unlock();
-
-	return 0;
 }
 
-static int __unlink_framebuffer(struct fb_info *fb_info);
+static void __unlink_framebuffer(struct fb_info *fb_info);
 
-static int do_unregister_framebuffer(struct fb_info *fb_info)
+static void do_unregister_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
-	ret = unbind_console(fb_info);
-
-	if (ret)
-		return -EINVAL;
+	unbind_console(fb_info);
 
 	pm_vt_switch_unregister(fb_info->dev);
 
@@ -1749,36 +1736,27 @@ static int do_unregister_framebuffer(struct fb_info *fb_info)
 
 	/* this may free fb info */
 	put_fb_info(fb_info);
-	return 0;
 }
 
-static int __unlink_framebuffer(struct fb_info *fb_info)
+static void __unlink_framebuffer(struct fb_info *fb_info)
 {
 	int i;
 
 	i = fb_info->node;
-	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
-		return -EINVAL;
+	if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
+		return;
 
 	if (fb_info->dev) {
 		device_destroy(fb_class, MKDEV(FB_MAJOR, i));
 		fb_info->dev = NULL;
 	}
-
-	return 0;
 }
 
-int unlink_framebuffer(struct fb_info *fb_info)
+void unlink_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
-	ret = __unlink_framebuffer(fb_info);
-	if (ret)
-		return ret;
+	__unlink_framebuffer(fb_info);
 
 	unbind_console(fb_info);
-
-	return 0;
 }
 EXPORT_SYMBOL(unlink_framebuffer);
 
@@ -1795,7 +1773,6 @@ EXPORT_SYMBOL(unlink_framebuffer);
 int remove_conflicting_framebuffers(struct apertures_struct *a,
 				    const char *name, bool primary)
 {
-	int ret;
 	bool do_free = false;
 
 	if (!a) {
@@ -1809,13 +1786,13 @@ int remove_conflicting_framebuffers(struct apertures_struct *a,
 	}
 
 	mutex_lock(&registration_lock);
-	ret = do_remove_conflicting_framebuffers(a, name, primary);
+	do_remove_conflicting_framebuffers(a, name, primary);
 	mutex_unlock(&registration_lock);
 
 	if (do_free)
 		kfree(a);
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(remove_conflicting_framebuffers);
 
@@ -1891,16 +1868,12 @@ EXPORT_SYMBOL(register_framebuffer);
  *      that the driver implements fb_open() and fb_release() to
  *      check that no processes are using the device.
  */
-int
+void
 unregister_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
 	mutex_lock(&registration_lock);
-	ret = do_unregister_framebuffer(fb_info);
+	do_unregister_framebuffer(fb_info);
 	mutex_unlock(&registration_lock);
-
-	return ret;
 }
 EXPORT_SYMBOL(unregister_framebuffer);
 
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 38fae1678939..44021e55b15c 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -627,8 +627,8 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf,
 
 /* drivers/video/fbmem.c */
 extern int register_framebuffer(struct fb_info *fb_info);
-extern int unregister_framebuffer(struct fb_info *fb_info);
-extern int unlink_framebuffer(struct fb_info *fb_info);
+extern void unregister_framebuffer(struct fb_info *fb_info);
+extern void unlink_framebuffer(struct fb_info *fb_info);
 extern int remove_conflicting_pci_framebuffers(struct pci_dev *pdev, int res_id,
 					       const char *name);
 extern int remove_conflicting_framebuffers(struct apertures_struct *a,
-- 
2.20.1

[PATCH 07/33] fbdev/aty128fb: Remove dead code

[Daniel Vetter]

Motivated because it contains a struct display, which is a fbcon
internal data structure that I want to rename. It seems to have been
formerly used in drivers, but that's very long time ago.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/aty/aty128fb.c | 64 ------------------------------
 1 file changed, 64 deletions(-)

diff --git a/drivers/video/fbdev/aty/aty128fb.c b/drivers/video/fbdev/aty/aty128fb.c
index 6cc46867ff57..c022ad7a49c2 100644
--- a/drivers/video/fbdev/aty/aty128fb.c
+++ b/drivers/video/fbdev/aty/aty128fb.c
@@ -2349,70 +2349,6 @@ static int aty128fb_ioctl(struct fb_info *info, u_int cmd, u_long arg)
 	return -EINVAL;
 }
 
-#if 0
-    /*
-     *  Accelerated functions
-     */
-
-static inline void aty128_rectcopy(int srcx, int srcy, int dstx, int dsty,
-				   u_int width, u_int height,
-				   struct fb_info_aty128 *par)
-{
-	u32 save_dp_datatype, save_dp_cntl, dstval;
-
-	if (!width || !height)
-		return;
-
-	dstval = depth_to_dst(par->current_par.crtc.depth);
-	if (dstval = DST_24BPP) {
-		srcx *= 3;
-		dstx *= 3;
-		width *= 3;
-	} else if (dstval = -EINVAL) {
-		printk("aty128fb: invalid depth or RGBA\n");
-		return;
-	}
-
-	wait_for_fifo(2, par);
-	save_dp_datatype = aty_ld_le32(DP_DATATYPE);
-	save_dp_cntl     = aty_ld_le32(DP_CNTL);
-
-	wait_for_fifo(6, par);
-	aty_st_le32(SRC_Y_X, (srcy << 16) | srcx);
-	aty_st_le32(DP_MIX, ROP3_SRCCOPY | DP_SRC_RECT);
-	aty_st_le32(DP_CNTL, DST_X_LEFT_TO_RIGHT | DST_Y_TOP_TO_BOTTOM);
-	aty_st_le32(DP_DATATYPE, save_dp_datatype | dstval | SRC_DSTCOLOR);
-
-	aty_st_le32(DST_Y_X, (dsty << 16) | dstx);
-	aty_st_le32(DST_HEIGHT_WIDTH, (height << 16) | width);
-
-	par->blitter_may_be_busy = 1;
-
-	wait_for_fifo(2, par);
-	aty_st_le32(DP_DATATYPE, save_dp_datatype);
-	aty_st_le32(DP_CNTL, save_dp_cntl);
-}
-
-
-    /*
-     * Text mode accelerated functions
-     */
-
-static void fbcon_aty128_bmove(struct display *p, int sy, int sx, int dy,
-			       int dx, int height, int width)
-{
-	sx     *= fontwidth(p);
-	sy     *= fontheight(p);
-	dx     *= fontwidth(p);
-	dy     *= fontheight(p);
-	width  *= fontwidth(p);
-	height *= fontheight(p);
-
-	aty128_rectcopy(sx, sy, dx, dy, width, height,
-			(struct fb_info_aty128 *)p->fb_info);
-}
-#endif /* 0 */
-
 static void aty128_set_suspend(struct aty128fb_par *par, int suspend)
 {
 	u32	pmgt;
-- 
2.20.1

[PATCH 10/33] fbcon: call fbcon_fb_(un)registered directly

[Daniel Vetter]

With

commit 6104c37094e729f3d4ce65797002112735d49cd1
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Tue Aug 1 17:32:07 2017 +0200

    fbcon: Make fbcon a built-time depency for fbdev

we have a static dependency between fbcon and fbdev, and we can
replace the indirection through the notifier chain with a function
call.

v2: Sam Ravnborg noticed that mach-pxa/am200epd.c has a notifier too,
and listens to this.

...

Looking at the code it seems to wait for some fb to show up, so that
it can get the framebuffer base address from the fb_info struct. I
suspect his is some firmware fbdev. Then it uses that information to
let the real fbdev driver (metronomefb.c by the looks) get at the
framebuffer memory.

This doesn't looke like it's easy to fix (except by deleting the
entire thing, seems untouched since 2008, we might be able to get away
with that), so let's just stuff a few #ifdef into fb.h and fbmem.c and
cry over them for a bit.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
Cc: Daniel Mack <daniel@zonque.org>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Konstantin Khorenko <khorenko@virtuozzo.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Steve Sakoman <sakoman@gmail.com>
Cc: Steve Sakoman <steve@sakoman.com>
Cc: linux-arm-kernel@lists.infradead.org
---
 arch/arm/mach-pxa/am200epd.c     | 13 +++++++++++--
 drivers/video/fbdev/core/fbcon.c | 14 +++-----------
 drivers/video/fbdev/core/fbmem.c | 24 +++++++++++++++++-------
 include/linux/fb.h               |  7 +++++--
 include/linux/fbcon.h            |  4 ++++
 5 files changed, 40 insertions(+), 22 deletions(-)

diff --git a/arch/arm/mach-pxa/am200epd.c b/arch/arm/mach-pxa/am200epd.c
index 50e18ed37fa6..cac0bb09db14 100644
--- a/arch/arm/mach-pxa/am200epd.c
+++ b/arch/arm/mach-pxa/am200epd.c
@@ -347,8 +347,17 @@ int __init am200_init(void)
 {
 	int ret;
 
-	/* before anything else, we request notification for any fb
-	 * creation events */
+	/*
+	 * Before anything else, we request notification for any fb
+	 * creation events.
+	 *
+	 * FIXME: This is terrible and needs to be nuked. The notifier is used
+	 * to get at the fb base address from the boot splash fb driver, which
+	 * is then passed to metronomefb. Instaed of metronomfb or this board
+	 * support file here figuring this out on their own.
+	 *
+	 * See also the #ifdef in fbmem.c.
+	 */
 	fb_register_client(&am200_fb_notif);
 
 	pxa2xx_mfp_config(ARRAY_AND_SIZE(am200_pin_config));
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 622d336cfc81..54d01f7284cb 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -3119,14 +3119,14 @@ static int fbcon_fb_unbind(int idx)
 }
 
 /* called with console_lock held */
-static int fbcon_fb_unregistered(struct fb_info *info)
+void fbcon_fb_unregistered(struct fb_info *info)
 {
 	int i, idx;
 
 	WARN_CONSOLE_UNLOCKED();
 
 	if (deferred_takeover)
-		return 0;
+		return;
 
 	idx = info->node;
 	for (i = first_fb_vc; i <= last_fb_vc; i++) {
@@ -3155,8 +3155,6 @@ static int fbcon_fb_unregistered(struct fb_info *info)
 
 	if (!num_registered_fb)
 		do_unregister_con_driver(&fb_con);
-
-	return 0;
 }
 
 /* called with console_lock held */
@@ -3215,7 +3213,7 @@ static inline void fbcon_select_primary(struct fb_info *info)
 #endif /* CONFIG_FRAMEBUFFER_DETECT_PRIMARY */
 
 /* called with console_lock held */
-static int fbcon_fb_registered(struct fb_info *info)
+int fbcon_fb_registered(struct fb_info *info)
 {
 	int ret = 0, i, idx;
 
@@ -3359,12 +3357,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 		idx = info->node;
 		ret = fbcon_fb_unbind(idx);
 		break;
-	case FB_EVENT_FB_REGISTERED:
-		ret = fbcon_fb_registered(info);
-		break;
-	case FB_EVENT_FB_UNREGISTERED:
-		ret = fbcon_fb_unregistered(info);
-		break;
 	case FB_EVENT_SET_CONSOLE_MAP:
 		/* called with console lock held */
 		con2fb = event->data;
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 8ba674ffb3c9..bed7698ad18a 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1660,7 +1660,6 @@ MODULE_PARM_DESC(lockless_register_fb,
 static int do_register_framebuffer(struct fb_info *fb_info)
 {
 	int i, ret;
-	struct fb_event event;
 	struct fb_videomode mode;
 
 	if (fb_check_foreignness(fb_info))
@@ -1723,7 +1722,14 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 	fb_add_videomode(&mode, &fb_info->modelist);
 	registered_fb[i] = fb_info;
 
-	event.info = fb_info;
+#ifdef CONFIG_GUMSTIX_AM200EPD
+	{
+		struct fb_event event;
+		event.info = fb_info;
+		fb_notifier_call_chain(FB_EVENT_FB_REGISTERED, &event);
+	}
+#endif
+
 	if (!lockless_register_fb)
 		console_lock();
 	else
@@ -1732,9 +1738,8 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 		ret = -ENODEV;
 		goto unlock_console;
 	}
-	ret = 0;
 
-	fb_notifier_call_chain(FB_EVENT_FB_REGISTERED, &event);
+	ret = fbcon_fb_registered(fb_info);
 	unlock_fb_info(fb_info);
 unlock_console:
 	if (!lockless_register_fb)
@@ -1771,7 +1776,6 @@ static int __unlink_framebuffer(struct fb_info *fb_info);
 
 static int do_unregister_framebuffer(struct fb_info *fb_info)
 {
-	struct fb_event event;
 	int ret;
 
 	ret = unbind_console(fb_info);
@@ -1789,9 +1793,15 @@ static int do_unregister_framebuffer(struct fb_info *fb_info)
 	registered_fb[fb_info->node] = NULL;
 	num_registered_fb--;
 	fb_cleanup_device(fb_info);
-	event.info = fb_info;
+#ifdef CONFIG_GUMSTIX_AM200EPD
+	{
+		struct fb_event event;
+		event.info = fb_info;
+		fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event);
+	}
+#endif
 	console_lock();
-	fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event);
+	fbcon_fb_unregistered(fb_info);
 	console_unlock();
 
 	/* this may free fb info */
diff --git a/include/linux/fb.h b/include/linux/fb.h
index f52ef0ad6781..288175fafaf6 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -136,10 +136,13 @@ struct fb_cursor_user {
 #define FB_EVENT_RESUME			0x03
 /*      An entry from the modelist was removed */
 #define FB_EVENT_MODE_DELETE            0x04
-/*      A driver registered itself */
+
+#ifdef CONFIG_GUMSTIX_AM200EPD
+/* only used by mach-pxa/am200epd.c */
 #define FB_EVENT_FB_REGISTERED          0x05
-/*      A driver unregistered itself */
 #define FB_EVENT_FB_UNREGISTERED        0x06
+#endif
+
 /*      CONSOLE-SPECIFIC: get console to framebuffer mapping */
 #define FB_EVENT_GET_CONSOLE_MAP        0x07
 /*      CONSOLE-SPECIFIC: set console to framebuffer mapping */
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index f68a7db14165..94a71e9e1257 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -4,9 +4,13 @@
 #ifdef CONFIG_FRAMEBUFFER_CONSOLE
 void __init fb_console_init(void);
 void __exit fb_console_exit(void);
+int fbcon_fb_registered(struct fb_info *info);
+void fbcon_fb_unregistered(struct fb_info *info);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
+static inline int fbcon_fb_registered(struct fb_info *info) { return 0; }
+static inline void fbcon_fb_unregistered(struct fb_info *info) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

[PATCH 16/33] fbdev: lock_fb_info cannot fail

[Daniel Vetter]

Ever since

commit c47747fde931c02455683bd00ea43eaa62f35b0e
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed May 11 14:58:34 2011 -0700

    fbmem: make read/write/ioctl use the frame buffer at open time

fbdev has gained proper refcounting for the fbinfo attached to any
open files, which means that the backing driver (stored in
fb_info->fbops) cannot untimely disappear anymore.

The only thing that can happen is that the entire device just outright
disappears and gets unregistered, but file_fb_info does check for
that. Except that it's racy - it only checks once at the start of a
file_ops, there's no guarantee that the underlying fbdev won't
untimely disappear. Aside: A proper way to fix that race is probably
to replicate the srcu trickery we've rolled out in drm.

But given that this race has existed since forever it's probably not
one we need to fix right away. do_unregister_framebuffer also nowhere
clears fb_info->fbops, hence the check in lock_fb_info can't possible
catch a disappearing fbdev later on.

Long story short: Ever since the above commit the fb_info->fbops
checks have essentially become dead code. Remove this all.

Aside from the file_ops callbacks, and stuff called from there
there's only register/unregister code left. If that goes wrong a driver
managed to register/unregister a device instance twice or in the wrong
order.  That's just a driver bug.

v2:
- fb_mmap had an open-coded version of the fbinfo->fops check, because
  it doesn't need the fbinfo->lock. Delete that too.
- Use the wrapper function in fb_open/release now, since no difference
  anymore.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Peter Rosin <peda@axentia.se>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/core/fbcmap.c |  6 +--
 drivers/video/fbdev/core/fbcon.c  |  3 +-
 drivers/video/fbdev/core/fbmem.c  | 73 +++++++------------------------
 include/linux/fb.h                |  5 ++-
 4 files changed, 23 insertions(+), 64 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcmap.c b/drivers/video/fbdev/core/fbcmap.c
index 2811c4afde01..e5ae33c1a8e8 100644
--- a/drivers/video/fbdev/core/fbcmap.c
+++ b/drivers/video/fbdev/core/fbcmap.c
@@ -285,11 +285,7 @@ int fb_set_user_cmap(struct fb_cmap_user *cmap, struct fb_info *info)
 		goto out;
 	}
 	umap.start = cmap->start;
-	if (!lock_fb_info(info)) {
-		rc = -ENODEV;
-		goto out;
-	}
-
+	lock_fb_info(info);
 	rc = fb_set_cmap(&umap, info);
 	unlock_fb_info(info);
 out:
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 54d01f7284cb..c3353db35adc 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -2364,8 +2364,7 @@ static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
 	}
 
 
-	if (!lock_fb_info(info))
-		return;
+	lock_fb_info(info);
 	event.info = info;
 	event.data = &blank;
 	fb_notifier_call_chain(FB_EVENT_CONBLANK, &event);
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index bed7698ad18a..d73762324ca2 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -80,17 +80,6 @@ static void put_fb_info(struct fb_info *fb_info)
 		fb_info->fbops->fb_destroy(fb_info);
 }
 
-int lock_fb_info(struct fb_info *info)
-{
-	mutex_lock(&info->lock);
-	if (!info->fbops) {
-		mutex_unlock(&info->lock);
-		return 0;
-	}
-	return 1;
-}
-EXPORT_SYMBOL(lock_fb_info);
-
 /*
  * Helpers
  */
@@ -1121,8 +1110,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 
 	switch (cmd) {
 	case FBIOGET_VSCREENINFO:
-		if (!lock_fb_info(info))
-			return -ENODEV;
+		lock_fb_info(info);
 		var = info->var;
 		unlock_fb_info(info);
 
@@ -1132,10 +1120,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 		if (copy_from_user(&var, argp, sizeof(var)))
 			return -EFAULT;
 		console_lock();
-		if (!lock_fb_info(info)) {
-			console_unlock();
-			return -ENODEV;
-		}
+		lock_fb_info(info);
 		info->flags |= FBINFO_MISC_USEREVENT;
 		ret = fb_set_var(info, &var);
 		info->flags &= ~FBINFO_MISC_USEREVENT;
@@ -1145,8 +1130,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 			ret = -EFAULT;
 		break;
 	case FBIOGET_FSCREENINFO:
-		if (!lock_fb_info(info))
-			return -ENODEV;
+		lock_fb_info(info);
 		fix = info->fix;
 		if (info->flags & FBINFO_HIDE_SMEM_START)
 			fix.smem_start = 0;
@@ -1162,8 +1146,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 	case FBIOGETCMAP:
 		if (copy_from_user(&cmap, argp, sizeof(cmap)))
 			return -EFAULT;
-		if (!lock_fb_info(info))
-			return -ENODEV;
+		lock_fb_info(info);
 		cmap_from = info->cmap;
 		unlock_fb_info(info);
 		ret = fb_cmap_to_user(&cmap_from, &cmap);
@@ -1172,10 +1155,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 		if (copy_from_user(&var, argp, sizeof(var)))
 			return -EFAULT;
 		console_lock();
-		if (!lock_fb_info(info)) {
-			console_unlock();
-			return -ENODEV;
-		}
+		lock_fb_info(info);
 		ret = fb_pan_display(info, &var);
 		unlock_fb_info(info);
 		console_unlock();
@@ -1192,8 +1172,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 			return -EINVAL;
 		con2fb.framebuffer = -1;
 		event.data = &con2fb;
-		if (!lock_fb_info(info))
-			return -ENODEV;
+		lock_fb_info(info);
 		event.info = info;
 		fb_notifier_call_chain(FB_EVENT_GET_CONSOLE_MAP, &event);
 		unlock_fb_info(info);
@@ -1214,10 +1193,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 		}
 		event.data = &con2fb;
 		console_lock();
-		if (!lock_fb_info(info)) {
-			console_unlock();
-			return -ENODEV;
-		}
+		lock_fb_info(info);
 		event.info = info;
 		ret = fb_notifier_call_chain(FB_EVENT_SET_CONSOLE_MAP, &event);
 		unlock_fb_info(info);
@@ -1225,10 +1201,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 		break;
 	case FBIOBLANK:
 		console_lock();
-		if (!lock_fb_info(info)) {
-			console_unlock();
-			return -ENODEV;
-		}
+		lock_fb_info(info);
 		info->flags |= FBINFO_MISC_USEREVENT;
 		ret = fb_blank(info, arg);
 		info->flags &= ~FBINFO_MISC_USEREVENT;
@@ -1236,8 +1209,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 		console_unlock();
 		break;
 	default:
-		if (!lock_fb_info(info))
-			return -ENODEV;
+		lock_fb_info(info);
 		fb = info->fbops;
 		if (fb->fb_ioctl)
 			ret = fb->fb_ioctl(info, cmd, arg);
@@ -1357,8 +1329,7 @@ static int fb_get_fscreeninfo(struct fb_info *info, unsigned int cmd,
 {
 	struct fb_fix_screeninfo fix;
 
-	if (!lock_fb_info(info))
-		return -ENODEV;
+	lock_fb_info(info);
 	fix = info->fix;
 	if (info->flags & FBINFO_HIDE_SMEM_START)
 		fix.smem_start = 0;
@@ -1418,8 +1389,6 @@ fb_mmap(struct file *file, struct vm_area_struct * vma)
 	if (!info)
 		return -ENODEV;
 	fb = info->fbops;
-	if (!fb)
-		return -ENODEV;
 	mutex_lock(&info->mm_lock);
 	if (fb->fb_mmap) {
 		int res;
@@ -1483,7 +1452,7 @@ __releases(&info->lock)
 	if (IS_ERR(info))
 		return PTR_ERR(info);
 
-	mutex_lock(&info->lock);
+	lock_fb_info(info);
 	if (!try_module_get(info->fbops->owner)) {
 		res = -ENODEV;
 		goto out;
@@ -1499,7 +1468,7 @@ __releases(&info->lock)
 		fb_deferred_io_open(info, inode, file);
 #endif
 out:
-	mutex_unlock(&info->lock);
+	unlock_fb_info(info);
 	if (res)
 		put_fb_info(info);
 	return res;
@@ -1512,11 +1481,11 @@ __releases(&info->lock)
 {
 	struct fb_info * const info = file->private_data;
 
-	mutex_lock(&info->lock);
+	lock_fb_info(info);
 	if (info->fbops->fb_release)
 		info->fbops->fb_release(info,1);
 	module_put(info->fbops->owner);
-	mutex_unlock(&info->lock);
+	unlock_fb_info(info);
 	put_fb_info(info);
 	return 0;
 }
@@ -1734,14 +1703,10 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 		console_lock();
 	else
 		atomic_inc(&ignore_console_lock_warning);
-	if (!lock_fb_info(fb_info)) {
-		ret = -ENODEV;
-		goto unlock_console;
-	}
-
+	lock_fb_info(fb_info);
 	ret = fbcon_fb_registered(fb_info);
 	unlock_fb_info(fb_info);
-unlock_console:
+
 	if (!lockless_register_fb)
 		console_unlock();
 	else
@@ -1759,11 +1724,7 @@ static int unbind_console(struct fb_info *fb_info)
 		return -EINVAL;
 
 	console_lock();
-	if (!lock_fb_info(fb_info)) {
-		console_unlock();
-		return -ENODEV;
-	}
-
+	lock_fb_info(fb_info);
 	event.info = fb_info;
 	ret = fb_notifier_call_chain(FB_EVENT_FB_UNBIND, &event);
 	unlock_fb_info(fb_info);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 288175fafaf6..aa8f18163151 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -663,7 +663,10 @@ extern struct class *fb_class;
 	for (i = 0; i < FB_MAX; i++)		\
 		if (!registered_fb[i]) {} else
 
-extern int lock_fb_info(struct fb_info *info);
+static inline void lock_fb_info(struct fb_info *info)
+{
+	mutex_lock(&info->lock);
+}
 
 static inline void unlock_fb_info(struct fb_info *info)
 {
-- 
2.20.1

[PATCH 17/33] fbcon: call fbcon_fb_bind directly

[Daniel Vetter]

Also remove the error return value. That's all errors for either
driver bugs (trying to unbind something that isn't bound), or errors
of the new driver that will take over.

There's nothing the outgoing driver can do about this anyway, so
switch over to void.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Kees Cook <keescook@chromium.org>
Cc: Konstantin Khorenko <khorenko@virtuozzo.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/core/fbcon.c | 24 +++++++-----------------
 drivers/video/fbdev/core/fbmem.c |  7 ++-----
 include/linux/fb.h               |  2 --
 include/linux/fbcon.h            |  2 ++
 4 files changed, 11 insertions(+), 24 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index c3353db35adc..f114b4c88796 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -3046,7 +3046,7 @@ static int fbcon_mode_deleted(struct fb_info *info,
 }
 
 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
-static int fbcon_unbind(void)
+static void fbcon_unbind(void)
 {
 	int ret;
 
@@ -3055,25 +3055,21 @@ static int fbcon_unbind(void)
 
 	if (!ret)
 		fbcon_has_console_bind = 0;
-
-	return ret;
 }
 #else
-static inline int fbcon_unbind(void)
-{
-	return -EINVAL;
-}
+static inline void fbcon_unbind(void) {}
 #endif /* CONFIG_VT_HW_CONSOLE_BINDING */
 
 /* called with console_lock held */
-static int fbcon_fb_unbind(int idx)
+void fbcon_fb_unbind(struct fb_info *info)
 {
 	int i, new_idx = -1, ret = 0;
+	int idx = info->node;
 
 	WARN_CONSOLE_UNLOCKED();
 
 	if (!fbcon_has_console_bind)
-		return 0;
+		return;
 
 	for (i = first_fb_vc; i <= last_fb_vc; i++) {
 		if (con2fb_map[i] != idx &&
@@ -3106,15 +3102,13 @@ static int fbcon_fb_unbind(int idx)
 								     idx, 0);
 					if (ret) {
 						con2fb_map[i] = idx;
-						return ret;
+						return;
 					}
 				}
 			}
 		}
-		ret = fbcon_unbind();
+		fbcon_unbind();
 	}
-
-	return ret;
 }
 
 /* called with console_lock held */
@@ -3352,10 +3346,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 		mode = event->data;
 		ret = fbcon_mode_deleted(info, mode);
 		break;
-	case FB_EVENT_FB_UNBIND:
-		idx = info->node;
-		ret = fbcon_fb_unbind(idx);
-		break;
 	case FB_EVENT_SET_CONSOLE_MAP:
 		/* called with console lock held */
 		con2fb = event->data;
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index d73762324ca2..f3fc2e5b193c 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1716,8 +1716,6 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 
 static int unbind_console(struct fb_info *fb_info)
 {
-	struct fb_event event;
-	int ret;
 	int i = fb_info->node;
 
 	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
@@ -1725,12 +1723,11 @@ static int unbind_console(struct fb_info *fb_info)
 
 	console_lock();
 	lock_fb_info(fb_info);
-	event.info = fb_info;
-	ret = fb_notifier_call_chain(FB_EVENT_FB_UNBIND, &event);
+	fbcon_fb_unbind(fb_info);
 	unlock_fb_info(fb_info);
 	console_unlock();
 
-	return ret;
+	return 0;
 }
 
 static int __unlink_framebuffer(struct fb_info *fb_info);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index aa8f18163151..b6ce041d9e13 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -158,8 +158,6 @@ struct fb_cursor_user {
 #define FB_EVENT_CONBLANK               0x0C
 /*      Get drawing requirements        */
 #define FB_EVENT_GET_REQ                0x0D
-/*      Unbind from the console if possible */
-#define FB_EVENT_FB_UNBIND              0x0E
 /*      CONSOLE-SPECIFIC: remap all consoles to new fb - for vga_switcheroo */
 #define FB_EVENT_REMAP_ALL_CONSOLE      0x0F
 /*      A hardware display blank early change occurred */
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index 94a71e9e1257..38d44fdb6d14 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -6,11 +6,13 @@ void __init fb_console_init(void);
 void __exit fb_console_exit(void);
 int fbcon_fb_registered(struct fb_info *info);
 void fbcon_fb_unregistered(struct fb_info *info);
+void fbcon_fb_unbind(struct fb_info *info);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
 static inline int fbcon_fb_registered(struct fb_info *info) { return 0; }
 static inline void fbcon_fb_unregistered(struct fb_info *info) {}
+static inline void fbcon_fb_unbind(struct fb_info *info) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

[PATCH 18/33] fbdev: make unregister/unlink functions not fail

[Daniel Vetter]

Except for driver bugs (which we'll catch with a WARN_ON) this is only
to report failures of the new driver taking over the console. There's
nothing the outgoing driver can do about that, and no one ever
bothered to actually look at these return values. So remove them all.

v2: fixup unregister_framebuffer in savagefb, fbtft, ivtvfb, and neofb
drivers, reported by kbuild.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/media/pci/ivtv/ivtvfb.c              |  6 +-
 drivers/staging/fbtft/fbtft-core.c           |  4 +-
 drivers/video/fbdev/core/fbmem.c             | 73 ++++++--------------
 drivers/video/fbdev/neofb.c                  |  9 +--
 drivers/video/fbdev/savage/savagefb_driver.c |  9 +--
 include/linux/fb.h                           |  4 +-
 6 files changed, 31 insertions(+), 74 deletions(-)

diff --git a/drivers/media/pci/ivtv/ivtvfb.c b/drivers/media/pci/ivtv/ivtvfb.c
index cfd21040d0e3..6435c72ff58e 100644
--- a/drivers/media/pci/ivtv/ivtvfb.c
+++ b/drivers/media/pci/ivtv/ivtvfb.c
@@ -1258,11 +1258,7 @@ static int ivtvfb_callback_cleanup(struct device *dev, void *p)
 	struct osd_info *oi = itv->osd_info;
 
 	if (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT) {
-		if (unregister_framebuffer(&itv->osd_info->ivtvfb_info)) {
-			IVTVFB_WARN("Framebuffer %d is in use, cannot unload\n",
-				       itv->instance);
-			return 0;
-		}
+		unregister_framebuffer(&itv->osd_info->ivtvfb_info);
 		IVTVFB_INFO("Unregister framebuffer %d\n", itv->instance);
 		itv->ivtvfb_restore = NULL;
 		ivtvfb_blank(FB_BLANK_VSYNC_SUSPEND, &oi->ivtvfb_info);
diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index 9b07badf4c6c..7cbc1bdd2d8a 100644
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -891,7 +891,9 @@ int fbtft_unregister_framebuffer(struct fb_info *fb_info)
 	if (par->fbtftops.unregister_backlight)
 		par->fbtftops.unregister_backlight(par);
 	fbtft_sysfs_exit(par);
-	return unregister_framebuffer(fb_info);
+	unregister_framebuffer(fb_info);
+
+	return 0;
 }
 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
 
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index f3fc2e5b193c..f3bcad30d3ba 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1590,13 +1590,13 @@ static bool fb_do_apertures_overlap(struct apertures_struct *gena,
 	return false;
 }
 
-static int do_unregister_framebuffer(struct fb_info *fb_info);
+static void do_unregister_framebuffer(struct fb_info *fb_info);
 
 #define VGA_FB_PHYS 0xA0000
-static int do_remove_conflicting_framebuffers(struct apertures_struct *a,
-					      const char *name, bool primary)
+static void do_remove_conflicting_framebuffers(struct apertures_struct *a,
+					       const char *name, bool primary)
 {
-	int i, ret;
+	int i;
 
 	/* check all firmware fbs and kick off if the base addr overlaps */
 	for_each_registered_fb(i) {
@@ -1612,13 +1612,9 @@ static int do_remove_conflicting_framebuffers(struct apertures_struct *a,
 
 			printk(KERN_INFO "fb%d: switching to %s from %s\n",
 			       i, name, registered_fb[i]->fix.id);
-			ret = do_unregister_framebuffer(registered_fb[i]);
-			if (ret)
-				return ret;
+			do_unregister_framebuffer(registered_fb[i]);
 		}
 	}
-
-	return 0;
 }
 
 static bool lockless_register_fb;
@@ -1634,11 +1630,9 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 	if (fb_check_foreignness(fb_info))
 		return -ENOSYS;
 
-	ret = do_remove_conflicting_framebuffers(fb_info->apertures,
-						 fb_info->fix.id,
-						 fb_is_primary_device(fb_info));
-	if (ret)
-		return ret;
+	do_remove_conflicting_framebuffers(fb_info->apertures,
+					   fb_info->fix.id,
+					   fb_is_primary_device(fb_info));
 
 	if (num_registered_fb = FB_MAX)
 		return -ENXIO;
@@ -1714,32 +1708,25 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 	return ret;
 }
 
-static int unbind_console(struct fb_info *fb_info)
+static void unbind_console(struct fb_info *fb_info)
 {
 	int i = fb_info->node;
 
-	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
-		return -EINVAL;
+	if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
+		return;
 
 	console_lock();
 	lock_fb_info(fb_info);
 	fbcon_fb_unbind(fb_info);
 	unlock_fb_info(fb_info);
 	console_unlock();
-
-	return 0;
 }
 
-static int __unlink_framebuffer(struct fb_info *fb_info);
+static void __unlink_framebuffer(struct fb_info *fb_info);
 
-static int do_unregister_framebuffer(struct fb_info *fb_info)
+static void do_unregister_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
-	ret = unbind_console(fb_info);
-
-	if (ret)
-		return -EINVAL;
+	unbind_console(fb_info);
 
 	pm_vt_switch_unregister(fb_info->dev);
 
@@ -1764,36 +1751,27 @@ static int do_unregister_framebuffer(struct fb_info *fb_info)
 
 	/* this may free fb info */
 	put_fb_info(fb_info);
-	return 0;
 }
 
-static int __unlink_framebuffer(struct fb_info *fb_info)
+static void __unlink_framebuffer(struct fb_info *fb_info)
 {
 	int i;
 
 	i = fb_info->node;
-	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
-		return -EINVAL;
+	if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
+		return;
 
 	if (fb_info->dev) {
 		device_destroy(fb_class, MKDEV(FB_MAJOR, i));
 		fb_info->dev = NULL;
 	}
-
-	return 0;
 }
 
-int unlink_framebuffer(struct fb_info *fb_info)
+void unlink_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
-	ret = __unlink_framebuffer(fb_info);
-	if (ret)
-		return ret;
+	__unlink_framebuffer(fb_info);
 
 	unbind_console(fb_info);
-
-	return 0;
 }
 EXPORT_SYMBOL(unlink_framebuffer);
 
@@ -1810,7 +1788,6 @@ EXPORT_SYMBOL(unlink_framebuffer);
 int remove_conflicting_framebuffers(struct apertures_struct *a,
 				    const char *name, bool primary)
 {
-	int ret;
 	bool do_free = false;
 
 	if (!a) {
@@ -1824,13 +1801,13 @@ int remove_conflicting_framebuffers(struct apertures_struct *a,
 	}
 
 	mutex_lock(&registration_lock);
-	ret = do_remove_conflicting_framebuffers(a, name, primary);
+	do_remove_conflicting_framebuffers(a, name, primary);
 	mutex_unlock(&registration_lock);
 
 	if (do_free)
 		kfree(a);
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(remove_conflicting_framebuffers);
 
@@ -1927,16 +1904,12 @@ EXPORT_SYMBOL(register_framebuffer);
  *      that the driver implements fb_open() and fb_release() to
  *      check that no processes are using the device.
  */
-int
+void
 unregister_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
 	mutex_lock(&registration_lock);
-	ret = do_unregister_framebuffer(fb_info);
+	do_unregister_framebuffer(fb_info);
 	mutex_unlock(&registration_lock);
-
-	return ret;
 }
 EXPORT_SYMBOL(unregister_framebuffer);
 
diff --git a/drivers/video/fbdev/neofb.c b/drivers/video/fbdev/neofb.c
index 5d3a444083f7..b770946a0920 100644
--- a/drivers/video/fbdev/neofb.c
+++ b/drivers/video/fbdev/neofb.c
@@ -2122,14 +2122,7 @@ static void neofb_remove(struct pci_dev *dev)
 	DBG("neofb_remove");
 
 	if (info) {
-		/*
-		 * If unregister_framebuffer fails, then
-		 * we will be leaving hooks that could cause
-		 * oopsen laying around.
-		 */
-		if (unregister_framebuffer(info))
-			printk(KERN_WARNING
-			       "neofb: danger danger!  Oopsen imminent!\n");
+		unregister_framebuffer(info);
 
 		neo_unmap_video(info);
 		fb_destroy_modedb(info->monspecs.modedb);
diff --git a/drivers/video/fbdev/savage/savagefb_driver.c b/drivers/video/fbdev/savage/savagefb_driver.c
index 47b78f0138c3..512789f5f884 100644
--- a/drivers/video/fbdev/savage/savagefb_driver.c
+++ b/drivers/video/fbdev/savage/savagefb_driver.c
@@ -2333,14 +2333,7 @@ static void savagefb_remove(struct pci_dev *dev)
 	DBG("savagefb_remove");
 
 	if (info) {
-		/*
-		 * If unregister_framebuffer fails, then
-		 * we will be leaving hooks that could cause
-		 * oopsen laying around.
-		 */
-		if (unregister_framebuffer(info))
-			printk(KERN_WARNING "savagefb: danger danger! "
-			       "Oopsen imminent!\n");
+		unregister_framebuffer(info);
 
 #ifdef CONFIG_FB_SAVAGE_I2C
 		savagefb_delete_i2c_busses(info);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index b6ce041d9e13..b90cf7d56bd8 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -634,8 +634,8 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf,
 
 /* drivers/video/fbmem.c */
 extern int register_framebuffer(struct fb_info *fb_info);
-extern int unregister_framebuffer(struct fb_info *fb_info);
-extern int unlink_framebuffer(struct fb_info *fb_info);
+extern void unregister_framebuffer(struct fb_info *fb_info);
+extern void unlink_framebuffer(struct fb_info *fb_info);
 extern int remove_conflicting_pci_framebuffers(struct pci_dev *pdev, int res_id,
 					       const char *name);
 extern int remove_conflicting_framebuffers(struct apertures_struct *a,
-- 
2.20.1

[PATCH 21/33] fbdev: directly call fbcon_suspended/resumed

[Daniel Vetter]

With the sh_mobile notifier removed we can just directly call the
fbcon code here.

v2: Remove now unused local variable.

v3: fixup !CONFIG_FRAMEBUFFER_CONSOLE, noticed by kbuild

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Konstantin Khorenko <khorenko@virtuozzo.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/core/fbcon.c | 10 ++--------
 drivers/video/fbdev/core/fbmem.c |  7 ++-----
 include/linux/fb.h               |  8 --------
 include/linux/fbcon.h            |  4 ++++
 4 files changed, 8 insertions(+), 21 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index f114b4c88796..24ea6e4fbee0 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -2919,7 +2919,7 @@ static int fbcon_set_origin(struct vc_data *vc)
 	return 0;
 }
 
-static void fbcon_suspended(struct fb_info *info)
+void fbcon_suspended(struct fb_info *info)
 {
 	struct vc_data *vc = NULL;
 	struct fbcon_ops *ops = info->fbcon_par;
@@ -2932,7 +2932,7 @@ static void fbcon_suspended(struct fb_info *info)
 	fbcon_cursor(vc, CM_ERASE);
 }
 
-static void fbcon_resumed(struct fb_info *info)
+void fbcon_resumed(struct fb_info *info)
 {
 	struct vc_data *vc;
 	struct fbcon_ops *ops = info->fbcon_par;
@@ -3330,12 +3330,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 	int idx, ret = 0;
 
 	switch(action) {
-	case FB_EVENT_SUSPEND:
-		fbcon_suspended(info);
-		break;
-	case FB_EVENT_RESUME:
-		fbcon_resumed(info);
-		break;
 	case FB_EVENT_MODE_CHANGE:
 		fbcon_modechanged(info);
 		break;
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index bee45e9405b8..73269dedcd45 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1917,17 +1917,14 @@ EXPORT_SYMBOL(unregister_framebuffer);
  */
 void fb_set_suspend(struct fb_info *info, int state)
 {
-	struct fb_event event;
-
 	WARN_CONSOLE_UNLOCKED();
 
-	event.info = info;
 	if (state) {
-		fb_notifier_call_chain(FB_EVENT_SUSPEND, &event);
+		fbcon_suspended(info);
 		info->state = FBINFO_STATE_SUSPENDED;
 	} else {
 		info->state = FBINFO_STATE_RUNNING;
-		fb_notifier_call_chain(FB_EVENT_RESUME, &event);
+		fbcon_resumed(info);
 	}
 }
 EXPORT_SYMBOL(fb_set_suspend);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index b90cf7d56bd8..794b386415b7 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -126,14 +126,6 @@ struct fb_cursor_user {
 
 /*	The resolution of the passed in fb_info about to change */ 
 #define FB_EVENT_MODE_CHANGE		0x01
-/*	The display on this fb_info is being suspended, no access to the
- *	framebuffer is allowed any more after that call returns
- */
-#define FB_EVENT_SUSPEND		0x02
-/*	The display on this fb_info was resumed, you can restore the display
- *	if you own it
- */
-#define FB_EVENT_RESUME			0x03
 /*      An entry from the modelist was removed */
 #define FB_EVENT_MODE_DELETE            0x04
 
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index 38d44fdb6d14..790c42ec7b5d 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -7,12 +7,16 @@ void __exit fb_console_exit(void);
 int fbcon_fb_registered(struct fb_info *info);
 void fbcon_fb_unregistered(struct fb_info *info);
 void fbcon_fb_unbind(struct fb_info *info);
+void fbcon_suspended(struct fb_info *info);
+void fbcon_resumed(struct fb_info *info);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
 static inline int fbcon_fb_registered(struct fb_info *info) { return 0; }
 static inline void fbcon_fb_unregistered(struct fb_info *info) {}
 static inline void fbcon_fb_unbind(struct fb_info *info) {}
+static inline void fbcon_suspended(struct fb_info *info) {}
+static inline void fbcon_resumed(struct fb_info *info) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

[PATCH 22/33] fbcon: Call fbcon_mode_deleted/new_modelist directly

[Daniel Vetter]

I'm not entirely clear on what new_modelist actually does, it seems
exclusively for a sysfs interface. Which in the end does amount to a
normal fb_set_par to check the mode, but then takes a different path
in both fbmem.c and fbcon.c.

I have no idea why these 2 paths are different, but then I also don't
really want to find out. So just do the simple conversion to a direct
function call.

v2: static inline for the dummy versions, I forgot.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Rosin <peda@axentia.se>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/core/fbcon.c | 14 +++-----------
 drivers/video/fbdev/core/fbmem.c | 22 +++++++---------------
 include/linux/fb.h               |  5 -----
 include/linux/fbcon.h            |  6 ++++++
 4 files changed, 16 insertions(+), 31 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 24ea6e4fbee0..35ecd25b385c 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -3019,8 +3019,8 @@ static void fbcon_set_all_vcs(struct fb_info *info)
 		fbcon_modechanged(info);
 }
 
-static int fbcon_mode_deleted(struct fb_info *info,
-			      struct fb_videomode *mode)
+int fbcon_mode_deleted(struct fb_info *info,
+		       struct fb_videomode *mode)
 {
 	struct fb_info *fb_info;
 	struct fbcon_display *p;
@@ -3262,7 +3262,7 @@ static void fbcon_fb_blanked(struct fb_info *info, int blank)
 	ops->blank_state = blank;
 }
 
-static void fbcon_new_modelist(struct fb_info *info)
+void fbcon_new_modelist(struct fb_info *info)
 {
 	int i;
 	struct vc_data *vc;
@@ -3324,7 +3324,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 {
 	struct fb_event *event = data;
 	struct fb_info *info = event->info;
-	struct fb_videomode *mode;
 	struct fb_con2fbmap *con2fb;
 	struct fb_blit_caps *caps;
 	int idx, ret = 0;
@@ -3336,10 +3335,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 	case FB_EVENT_MODE_CHANGE_ALL:
 		fbcon_set_all_vcs(info);
 		break;
-	case FB_EVENT_MODE_DELETE:
-		mode = event->data;
-		ret = fbcon_mode_deleted(info, mode);
-		break;
 	case FB_EVENT_SET_CONSOLE_MAP:
 		/* called with console lock held */
 		con2fb = event->data;
@@ -3353,9 +3348,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 	case FB_EVENT_BLANK:
 		fbcon_fb_blanked(info, *(int *)event->data);
 		break;
-	case FB_EVENT_NEW_MODELIST:
-		fbcon_new_modelist(info);
-		break;
 	case FB_EVENT_GET_REQ:
 		caps = event->data;
 		fbcon_get_requirement(info, caps);
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 73269dedcd45..cbdd141e7695 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -966,16 +966,11 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
 		/* make sure we don't delete the videomode of current var */
 		ret = fb_mode_is_equal(&mode1, &mode2);
 
-		if (!ret) {
-		    struct fb_event event;
-
-		    event.info = info;
-		    event.data = &mode1;
-		    ret = fb_notifier_call_chain(FB_EVENT_MODE_DELETE, &event);
-		}
+		if (!ret)
+			fbcon_mode_deleted(info, &mode1);
 
 		if (!ret)
-		    fb_delete_videomode(&mode1, &info->modelist);
+			fb_delete_videomode(&mode1, &info->modelist);
 
 
 		ret = (ret) ? -EINVAL : 0;
@@ -1992,7 +1987,6 @@ subsys_initcall(fbmem_init);
 
 int fb_new_modelist(struct fb_info *info)
 {
-	struct fb_event event;
 	struct fb_var_screeninfo var = info->var;
 	struct list_head *pos, *n;
 	struct fb_modelist *modelist;
@@ -2012,14 +2006,12 @@ int fb_new_modelist(struct fb_info *info)
 		}
 	}
 
-	err = 1;
+	if (list_empty(&info->modelist))
+		return 1;
 
-	if (!list_empty(&info->modelist)) {
-		event.info = info;
-		err = fb_notifier_call_chain(FB_EVENT_NEW_MODELIST, &event);
-	}
+	fbcon_new_modelist(info);
 
-	return err;
+	return 0;
 }
 
 MODULE_LICENSE("GPL");
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 794b386415b7..7a788ed8c7b5 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -126,8 +126,6 @@ struct fb_cursor_user {
 
 /*	The resolution of the passed in fb_info about to change */ 
 #define FB_EVENT_MODE_CHANGE		0x01
-/*      An entry from the modelist was removed */
-#define FB_EVENT_MODE_DELETE            0x04
 
 #ifdef CONFIG_GUMSTIX_AM200EPD
 /* only used by mach-pxa/am200epd.c */
@@ -142,9 +140,6 @@ struct fb_cursor_user {
 /*      A hardware display blank change occurred */
 #define FB_EVENT_BLANK                  0x09
 /*      Private modelist is to be replaced */
-#define FB_EVENT_NEW_MODELIST           0x0A
-/*	The resolution of the passed in fb_info about to change and
-        all vc's should be changed         */
 #define FB_EVENT_MODE_CHANGE_ALL	0x0B
 /*	A software display blank change occurred */
 #define FB_EVENT_CONBLANK               0x0C
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index 790c42ec7b5d..c139834342f5 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -9,6 +9,9 @@ void fbcon_fb_unregistered(struct fb_info *info);
 void fbcon_fb_unbind(struct fb_info *info);
 void fbcon_suspended(struct fb_info *info);
 void fbcon_resumed(struct fb_info *info);
+int fbcon_mode_deleted(struct fb_info *info,
+		       struct fb_videomode *mode);
+void fbcon_new_modelist(struct fb_info *info);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
@@ -17,6 +20,9 @@ static inline void fbcon_fb_unregistered(struct fb_info *info) {}
 static inline void fbcon_fb_unbind(struct fb_info *info) {}
 static inline void fbcon_suspended(struct fb_info *info) {}
 static inline void fbcon_resumed(struct fb_info *info) {}
+static inline int fbcon_mode_deleted(struct fb_info *info,
+				     struct fb_videomode *mode) { return 0; }
+static inline void fbcon_new_modelist(struct fb_info *info) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

[PATCH 23/33] fbdev: Call fbcon_get_requirement directly

[Daniel Vetter]

Pretty simple case really.

v2: Forgot to remove a break;

v3: Add static inline to the dummy versions.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/core/fbcon.c | 9 ++-------
 drivers/video/fbdev/core/fbmem.c | 5 +----
 include/linux/fb.h               | 2 --
 include/linux/fbcon.h            | 4 ++++
 4 files changed, 7 insertions(+), 13 deletions(-)

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 35ecd25b385c..259cdd118475 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -3283,8 +3283,8 @@ void fbcon_new_modelist(struct fb_info *info)
 	}
 }
 
-static void fbcon_get_requirement(struct fb_info *info,
-				  struct fb_blit_caps *caps)
+void fbcon_get_requirement(struct fb_info *info,
+			   struct fb_blit_caps *caps)
 {
 	struct vc_data *vc;
 	struct fbcon_display *p;
@@ -3325,7 +3325,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 	struct fb_event *event = data;
 	struct fb_info *info = event->info;
 	struct fb_con2fbmap *con2fb;
-	struct fb_blit_caps *caps;
 	int idx, ret = 0;
 
 	switch(action) {
@@ -3348,10 +3347,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 	case FB_EVENT_BLANK:
 		fbcon_fb_blanked(info, *(int *)event->data);
 		break;
-	case FB_EVENT_GET_REQ:
-		caps = event->data;
-		fbcon_get_requirement(info, caps);
-		break;
 	case FB_EVENT_REMAP_ALL_CONSOLE:
 		idx = info->node;
 		fbcon_remap_all(idx);
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index cbdd141e7695..ddc0c16b8bbf 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -932,16 +932,13 @@ EXPORT_SYMBOL(fb_pan_display);
 static int fb_check_caps(struct fb_info *info, struct fb_var_screeninfo *var,
 			 u32 activate)
 {
-	struct fb_event event;
 	struct fb_blit_caps caps, fbcaps;
 	int err = 0;
 
 	memset(&caps, 0, sizeof(caps));
 	memset(&fbcaps, 0, sizeof(fbcaps));
 	caps.flags = (activate & FB_ACTIVATE_ALL) ? 1 : 0;
-	event.info = info;
-	event.data = &caps;
-	fb_notifier_call_chain(FB_EVENT_GET_REQ, &event);
+	fbcon_get_requirement(info, &caps);
 	info->fbops->fb_get_caps(info, &fbcaps, var);
 
 	if (((fbcaps.x ^ caps.x) & caps.x) ||
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 7a788ed8c7b5..0d86aa31bf8d 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -143,8 +143,6 @@ struct fb_cursor_user {
 #define FB_EVENT_MODE_CHANGE_ALL	0x0B
 /*	A software display blank change occurred */
 #define FB_EVENT_CONBLANK               0x0C
-/*      Get drawing requirements        */
-#define FB_EVENT_GET_REQ                0x0D
 /*      CONSOLE-SPECIFIC: remap all consoles to new fb - for vga_switcheroo */
 #define FB_EVENT_REMAP_ALL_CONSOLE      0x0F
 /*      A hardware display blank early change occurred */
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index c139834342f5..305e4f2eddac 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -12,6 +12,8 @@ void fbcon_resumed(struct fb_info *info);
 int fbcon_mode_deleted(struct fb_info *info,
 		       struct fb_videomode *mode);
 void fbcon_new_modelist(struct fb_info *info);
+void fbcon_get_requirement(struct fb_info *info,
+			   struct fb_blit_caps *caps);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
@@ -23,6 +25,8 @@ static inline void fbcon_resumed(struct fb_info *info) {}
 static inline int fbcon_mode_deleted(struct fb_info *info,
 				     struct fb_videomode *mode) { return 0; }
 static inline void fbcon_new_modelist(struct fb_info *info) {}
+static inline void fbcon_get_requirement(struct fb_info *info,
+					 struct fb_blit_caps *caps) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

[PATCH 24/33] Revert "backlight/fbcon: Add FB_EVENT_CONBLANK"

[Daniel Vetter]

This reverts commit 994efacdf9a087b52f71e620b58dfa526b0cf928.

The justification is that if hw blanking fails (i.e. fbops->fb_blank)
fails, then we still want to shut down the backlight. Which is exactly
_not_ what fb_blank() does and so rather inconsistent if we end up
with different behaviour between fbcon and direct fbdev usage. Given
that the entire notifier maze is getting in the way anyway I figured
it's simplest to revert this not well justified commit.

v2: Add static inline to the dummy version.

Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/backlight/backlight.c |  2 +-
 drivers/video/fbdev/core/fbcon.c    | 14 +-------------
 drivers/video/fbdev/core/fbmem.c    |  1 +
 include/linux/fb.h                  |  4 +---
 include/linux/fbcon.h               |  2 ++
 5 files changed, 6 insertions(+), 17 deletions(-)

diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index deb824bef6e2..c55590ec0057 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -46,7 +46,7 @@ static int fb_notifier_callback(struct notifier_block *self,
 	int fb_blank = 0;
 
 	/* If we aren't interested in this event, skip it immediately ... */
-	if (event != FB_EVENT_BLANK && event != FB_EVENT_CONBLANK)
+	if (event != FB_EVENT_BLANK)
 		return 0;
 
 	bd = container_of(self, struct backlight_device, fb_notif);
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 259cdd118475..d9f545f1a81b 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -2350,8 +2350,6 @@ static int fbcon_switch(struct vc_data *vc)
 static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
 				int blank)
 {
-	struct fb_event event;
-
 	if (blank) {
 		unsigned short charmask = vc->vc_hi_font_mask ?
 			0x1ff : 0xff;
@@ -2362,13 +2360,6 @@ static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
 		fbcon_clear(vc, 0, 0, vc->vc_rows, vc->vc_cols);
 		vc->vc_video_erase_char = oldc;
 	}
-
-
-	lock_fb_info(info);
-	event.info = info;
-	event.data = &blank;
-	fb_notifier_call_chain(FB_EVENT_CONBLANK, &event);
-	unlock_fb_info(info);
 }
 
 static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
@@ -3240,7 +3231,7 @@ int fbcon_fb_registered(struct fb_info *info)
 	return ret;
 }
 
-static void fbcon_fb_blanked(struct fb_info *info, int blank)
+void fbcon_fb_blanked(struct fb_info *info, int blank)
 {
 	struct fbcon_ops *ops = info->fbcon_par;
 	struct vc_data *vc;
@@ -3344,9 +3335,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 		con2fb = event->data;
 		con2fb->framebuffer = con2fb_map[con2fb->console - 1];
 		break;
-	case FB_EVENT_BLANK:
-		fbcon_fb_blanked(info, *(int *)event->data);
-		break;
 	case FB_EVENT_REMAP_ALL_CONSOLE:
 		idx = info->node;
 		fbcon_remap_all(idx);
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index ddc0c16b8bbf..9366fbe99a58 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1068,6 +1068,7 @@ fb_blank(struct fb_info *info, int blank)
 	event.data = &blank;
 
 	early_ret = fb_notifier_call_chain(FB_EARLY_EVENT_BLANK, &event);
+	fbcon_fb_blanked(info, blank);
 
 	if (info->fbops->fb_blank)
  		ret = info->fbops->fb_blank(blank, info);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 0d86aa31bf8d..1e66fac3124f 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -137,12 +137,10 @@ struct fb_cursor_user {
 #define FB_EVENT_GET_CONSOLE_MAP        0x07
 /*      CONSOLE-SPECIFIC: set console to framebuffer mapping */
 #define FB_EVENT_SET_CONSOLE_MAP        0x08
-/*      A hardware display blank change occurred */
+/*      A display blank is requested       */
 #define FB_EVENT_BLANK                  0x09
 /*      Private modelist is to be replaced */
 #define FB_EVENT_MODE_CHANGE_ALL	0x0B
-/*	A software display blank change occurred */
-#define FB_EVENT_CONBLANK               0x0C
 /*      CONSOLE-SPECIFIC: remap all consoles to new fb - for vga_switcheroo */
 #define FB_EVENT_REMAP_ALL_CONSOLE      0x0F
 /*      A hardware display blank early change occurred */
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index 305e4f2eddac..d67d7ec51ef9 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -14,6 +14,7 @@ int fbcon_mode_deleted(struct fb_info *info,
 void fbcon_new_modelist(struct fb_info *info);
 void fbcon_get_requirement(struct fb_info *info,
 			   struct fb_blit_caps *caps);
+void fbcon_fb_blanked(struct fb_info *info, int blank);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
@@ -27,6 +28,7 @@ static inline int fbcon_mode_deleted(struct fb_info *info,
 static inline void fbcon_new_modelist(struct fb_info *info) {}
 static inline void fbcon_get_requirement(struct fb_info *info,
 					 struct fb_blit_caps *caps) {}
+static inline void fbcon_fb_blanked(struct fb_info *info, int blank) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

[PATCH 28/33] fbcon: replace FB_EVENT_MODE_CHANGE/_ALL with direct calls

[Daniel Vetter]

Create a new wrapper function for this, feels like there's some
refactoring room here between the two modes.

v2: backlight notifier is also interested in the mode change event,
it calls lcd->set_mode, of which there are 3 implementations. Thanks
to Maarten for spotting this. So we keep that. We can ditch the differentiation
between mode change and all mode changes (because backlight notifier
doesn't care), and we can drop the FBINFO_MISC_USEREVENT stuff too,
because that's just to prevent recursion between fbmem.c and fbcon.c.

While at it flatten the control flow a bit.

v3: Need to add a static inline to the dummy function.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/backlight/lcd.c          |  1 -
 drivers/video/fbdev/core/fbcon.c       | 15 +++++++++------
 drivers/video/fbdev/core/fbmem.c       | 21 ++++++++++-----------
 drivers/video/fbdev/sh_mobile_lcdcfb.c | 11 +----------
 include/linux/fb.h                     |  2 --
 include/linux/fbcon.h                  |  2 ++
 6 files changed, 22 insertions(+), 30 deletions(-)

diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c
index 4b40c6a4d441..a758039475d0 100644
--- a/drivers/video/backlight/lcd.c
+++ b/drivers/video/backlight/lcd.c
@@ -33,7 +33,6 @@ static int fb_notifier_callback(struct notifier_block *self,
 	switch (event) {
 	case FB_EVENT_BLANK:
 	case FB_EVENT_MODE_CHANGE:
-	case FB_EVENT_MODE_CHANGE_ALL:
 	case FB_EARLY_EVENT_BLANK:
 	case FB_R_EARLY_EVENT_BLANK:
 		break;
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 8a67505167ae..a07c261da53a 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -3009,6 +3009,15 @@ static void fbcon_set_all_vcs(struct fb_info *info)
 		fbcon_modechanged(info);
 }
 
+
+void fbcon_update_vcs(struct fb_info *info, bool all)
+{
+	if (all)
+		fbcon_set_all_vcs(info);
+	else
+		fbcon_modechanged(info);
+}
+
 int fbcon_mode_deleted(struct fb_info *info,
 		       struct fb_videomode *mode)
 {
@@ -3318,12 +3327,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 	int idx, ret = 0;
 
 	switch(action) {
-	case FB_EVENT_MODE_CHANGE:
-		fbcon_modechanged(info);
-		break;
-	case FB_EVENT_MODE_CHANGE_ALL:
-		fbcon_set_all_vcs(info);
-		break;
 	case FB_EVENT_SET_CONSOLE_MAP:
 		/* called with console lock held */
 		con2fb = event->data;
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index 96805fe85332..dd1a708df1a7 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -957,6 +957,7 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
 	u32 activate;
 	struct fb_var_screeninfo old_var;
 	struct fb_videomode mode;
+	struct fb_event event;
 
 	if (var->activate & FB_ACTIVATE_INV_MODE) {
 		struct fb_videomode mode1, mode2;
@@ -1039,19 +1040,17 @@ fb_set_var(struct fb_info *info, struct fb_var_screeninfo *var)
 	    !list_empty(&info->modelist))
 		ret = fb_add_videomode(&mode, &info->modelist);
 
-	if (!ret && (flags & FBINFO_MISC_USEREVENT)) {
-		struct fb_event event;
-		int evnt = (activate & FB_ACTIVATE_ALL) ?
-			FB_EVENT_MODE_CHANGE_ALL :
-			FB_EVENT_MODE_CHANGE;
+	if (ret)
+		return ret;
 
-		info->flags &= ~FBINFO_MISC_USEREVENT;
-		event.info = info;
-		event.data = &mode;
-		fb_notifier_call_chain(evnt, &event);
-	}
+	event.info = info;
+	event.data = &mode;
+	fb_notifier_call_chain(FB_EVENT_MODE_CHANGE, &event);
 
-	return ret;
+	if (flags & FBINFO_MISC_USEREVENT)
+		fbcon_update_vcs(info, activate & FB_ACTIVATE_ALL);
+
+	return 0;
 }
 EXPORT_SYMBOL(fb_set_var);
 
diff --git a/drivers/video/fbdev/sh_mobile_lcdcfb.c b/drivers/video/fbdev/sh_mobile_lcdcfb.c
index 0d7a044852d7..bb1a610d0363 100644
--- a/drivers/video/fbdev/sh_mobile_lcdcfb.c
+++ b/drivers/video/fbdev/sh_mobile_lcdcfb.c
@@ -1776,8 +1776,6 @@ static void sh_mobile_fb_reconfig(struct fb_info *info)
 	struct sh_mobile_lcdc_chan *ch = info->par;
 	struct fb_var_screeninfo var;
 	struct fb_videomode mode;
-	struct fb_event event;
-	int evnt = FB_EVENT_MODE_CHANGE_ALL;
 
 	if (ch->use_count > 1 || (ch->use_count = 1 && !info->fbcon_par))
 		/* More framebuffer users are active */
@@ -1799,14 +1797,7 @@ static void sh_mobile_fb_reconfig(struct fb_info *info)
 		/* Couldn't reconfigure, hopefully, can continue as before */
 		return;
 
-	/*
-	 * fb_set_var() calls the notifier change internally, only if
-	 * FBINFO_MISC_USEREVENT flag is set. Since we do not want to fake a
-	 * user event, we have to call the chain ourselves.
-	 */
-	event.info = info;
-	event.data = &ch->display.mode;
-	fb_notifier_call_chain(evnt, &event);
+	fbcon_update_vcs(info, true);
 }
 
 /*
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 1e66fac3124f..f9c212f9b661 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -139,8 +139,6 @@ struct fb_cursor_user {
 #define FB_EVENT_SET_CONSOLE_MAP        0x08
 /*      A display blank is requested       */
 #define FB_EVENT_BLANK                  0x09
-/*      Private modelist is to be replaced */
-#define FB_EVENT_MODE_CHANGE_ALL	0x0B
 /*      CONSOLE-SPECIFIC: remap all consoles to new fb - for vga_switcheroo */
 #define FB_EVENT_REMAP_ALL_CONSOLE      0x0F
 /*      A hardware display blank early change occurred */
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index d67d7ec51ef9..de31eeb22c97 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -15,6 +15,7 @@ void fbcon_new_modelist(struct fb_info *info);
 void fbcon_get_requirement(struct fb_info *info,
 			   struct fb_blit_caps *caps);
 void fbcon_fb_blanked(struct fb_info *info, int blank);
+void fbcon_update_vcs(struct fb_info *info, bool all);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
@@ -29,6 +30,7 @@ static inline void fbcon_new_modelist(struct fb_info *info) {}
 static inline void fbcon_get_requirement(struct fb_info *info,
 					 struct fb_blit_caps *caps) {}
 static inline void fbcon_fb_blanked(struct fb_info *info, int blank) {}
+static inline void fbcon_update_vcs(struct fb_info *info, bool all) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

[PATCH 29/33] vgaswitcheroo: call fbcon_remap_all directly

[Daniel Vetter]

While at it, clean up the interface a bit and push the console locking
into fbcon.c.

v2: Remove now outdated comment (Lukas).

v3: Forgot to add static inline to the dummy function.

Acked-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Yisheng Xie <ysxie@foxmail.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/gpu/vga/vga_switcheroo.c | 11 +++--------
 drivers/video/fbdev/core/fbcon.c | 14 +++++---------
 include/linux/fb.h               |  2 --
 include/linux/fbcon.h            |  2 ++
 4 files changed, 10 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index a132c37d7334..65d7541c413a 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -35,6 +35,7 @@
 #include <linux/debugfs.h>
 #include <linux/fb.h>
 #include <linux/fs.h>
+#include <linux/fbcon.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/pm_domain.h>
@@ -736,14 +737,8 @@ static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
 	if (!active->driver_power_control)
 		set_audio_state(active->id, VGA_SWITCHEROO_OFF);
 
-	if (new_client->fb_info) {
-		struct fb_event event;
-
-		console_lock();
-		event.info = new_client->fb_info;
-		fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
-		console_unlock();
-	}
+	if (new_client->fb_info)
+		fbcon_remap_all(new_client->fb_info);
 
 	mutex_lock(&vgasr_priv.mux_hw_lock);
 	ret = vgasr_priv.handler->switchto(new_client->id);
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index a07c261da53a..e08e984e2511 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -3149,17 +3149,16 @@ void fbcon_fb_unregistered(struct fb_info *info)
 		do_unregister_con_driver(&fb_con);
 }
 
-/* called with console_lock held */
-static void fbcon_remap_all(int idx)
+void fbcon_remap_all(struct fb_info *info)
 {
-	int i;
-
-	WARN_CONSOLE_UNLOCKED();
+	int i, idx = info->node;
 
+	console_lock();
 	if (deferred_takeover) {
 		for (i = first_fb_vc; i <= last_fb_vc; i++)
 			con2fb_map_boot[i] = idx;
 		fbcon_map_override();
+		console_unlock();
 		return;
 	}
 
@@ -3172,6 +3171,7 @@ static void fbcon_remap_all(int idx)
 		       first_fb_vc + 1, last_fb_vc + 1);
 		info_idx = idx;
 	}
+	console_unlock();
 }
 
 #ifdef CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY
@@ -3337,10 +3337,6 @@ static int fbcon_event_notify(struct notifier_block *self,
 		con2fb = event->data;
 		con2fb->framebuffer = con2fb_map[con2fb->console - 1];
 		break;
-	case FB_EVENT_REMAP_ALL_CONSOLE:
-		idx = info->node;
-		fbcon_remap_all(idx);
-		break;
 	}
 	return ret;
 }
diff --git a/include/linux/fb.h b/include/linux/fb.h
index f9c212f9b661..25e4b885f5b3 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -139,8 +139,6 @@ struct fb_cursor_user {
 #define FB_EVENT_SET_CONSOLE_MAP        0x08
 /*      A display blank is requested       */
 #define FB_EVENT_BLANK                  0x09
-/*      CONSOLE-SPECIFIC: remap all consoles to new fb - for vga_switcheroo */
-#define FB_EVENT_REMAP_ALL_CONSOLE      0x0F
 /*      A hardware display blank early change occurred */
 #define FB_EARLY_EVENT_BLANK		0x10
 /*      A hardware display blank revert early change occurred */
diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
index de31eeb22c97..69f900d289b2 100644
--- a/include/linux/fbcon.h
+++ b/include/linux/fbcon.h
@@ -16,6 +16,7 @@ void fbcon_get_requirement(struct fb_info *info,
 			   struct fb_blit_caps *caps);
 void fbcon_fb_blanked(struct fb_info *info, int blank);
 void fbcon_update_vcs(struct fb_info *info, bool all);
+void fbcon_remap_all(struct fb_info *info);
 #else
 static inline void fb_console_init(void) {}
 static inline void fb_console_exit(void) {}
@@ -31,6 +32,7 @@ static inline void fbcon_get_requirement(struct fb_info *info,
 					 struct fb_blit_caps *caps) {}
 static inline void fbcon_fb_blanked(struct fb_info *info, int blank) {}
 static inline void fbcon_update_vcs(struct fb_info *info, bool all) {}
+static inline void fbcon_remap_all(struct fb_info *info) {}
 #endif
 
 #endif /* _LINUX_FBCON_H */
-- 
2.20.1

Re: [PATCH 24/33] Revert "backlight/fbcon: Add FB_EVENT_CONBLANK"

[Daniel Thompson]

On Fri, May 24, 2019 at 10:53:45AM +0200, Daniel Vetter wrote:
> This reverts commit 994efacdf9a087b52f71e620b58dfa526b0cf928.
> 
> The justification is that if hw blanking fails (i.e. fbops->fb_blank)
> fails, then we still want to shut down the backlight. Which is exactly
> _not_ what fb_blank() does and so rather inconsistent if we end up
> with different behaviour between fbcon and direct fbdev usage. Given
> that the entire notifier maze is getting in the way anyway I figured
> it's simplest to revert this not well justified commit.
> 
> v2: Add static inline to the dummy version.
> 
> Cc: Richard Purdie <rpurdie@rpsys.net>
> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> Cc: Daniel Thompson <daniel.thompson@linaro.org>
> Cc: Jingoo Han <jingoohan1@gmail.com>
> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Hans de Goede <hdegoede@redhat.com>
> Cc: Yisheng Xie <ysxie@foxmail.com>
> Cc: linux-fbdev@vger.kernel.org

Hi Daniel

When this goes round again could you add me to the covering letter?

I looked at all three of the patches and no objections on my side but
I'm reluctant to send out acks because I'm not sure I understood the
wider picture well enough.


Daniel.


> ---
>  drivers/video/backlight/backlight.c |  2 +-
>  drivers/video/fbdev/core/fbcon.c    | 14 +-------------
>  drivers/video/fbdev/core/fbmem.c    |  1 +
>  include/linux/fb.h                  |  4 +---
>  include/linux/fbcon.h               |  2 ++
>  5 files changed, 6 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> index deb824bef6e2..c55590ec0057 100644
> --- a/drivers/video/backlight/backlight.c
> +++ b/drivers/video/backlight/backlight.c
> @@ -46,7 +46,7 @@ static int fb_notifier_callback(struct notifier_block *self,
>  	int fb_blank = 0;
>  
>  	/* If we aren't interested in this event, skip it immediately ... */
> -	if (event != FB_EVENT_BLANK && event != FB_EVENT_CONBLANK)
> +	if (event != FB_EVENT_BLANK)
>  		return 0;
>  
>  	bd = container_of(self, struct backlight_device, fb_notif);
> diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
> index 259cdd118475..d9f545f1a81b 100644
> --- a/drivers/video/fbdev/core/fbcon.c
> +++ b/drivers/video/fbdev/core/fbcon.c
> @@ -2350,8 +2350,6 @@ static int fbcon_switch(struct vc_data *vc)
>  static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
>  				int blank)
>  {
> -	struct fb_event event;
> -
>  	if (blank) {
>  		unsigned short charmask = vc->vc_hi_font_mask ?
>  			0x1ff : 0xff;
> @@ -2362,13 +2360,6 @@ static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
>  		fbcon_clear(vc, 0, 0, vc->vc_rows, vc->vc_cols);
>  		vc->vc_video_erase_char = oldc;
>  	}
> -
> -
> -	lock_fb_info(info);
> -	event.info = info;
> -	event.data = &blank;
> -	fb_notifier_call_chain(FB_EVENT_CONBLANK, &event);
> -	unlock_fb_info(info);
>  }
>  
>  static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
> @@ -3240,7 +3231,7 @@ int fbcon_fb_registered(struct fb_info *info)
>  	return ret;
>  }
>  
> -static void fbcon_fb_blanked(struct fb_info *info, int blank)
> +void fbcon_fb_blanked(struct fb_info *info, int blank)
>  {
>  	struct fbcon_ops *ops = info->fbcon_par;
>  	struct vc_data *vc;
> @@ -3344,9 +3335,6 @@ static int fbcon_event_notify(struct notifier_block *self,
>  		con2fb = event->data;
>  		con2fb->framebuffer = con2fb_map[con2fb->console - 1];
>  		break;
> -	case FB_EVENT_BLANK:
> -		fbcon_fb_blanked(info, *(int *)event->data);
> -		break;
>  	case FB_EVENT_REMAP_ALL_CONSOLE:
>  		idx = info->node;
>  		fbcon_remap_all(idx);
> diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
> index ddc0c16b8bbf..9366fbe99a58 100644
> --- a/drivers/video/fbdev/core/fbmem.c
> +++ b/drivers/video/fbdev/core/fbmem.c
> @@ -1068,6 +1068,7 @@ fb_blank(struct fb_info *info, int blank)
>  	event.data = &blank;
>  
>  	early_ret = fb_notifier_call_chain(FB_EARLY_EVENT_BLANK, &event);
> +	fbcon_fb_blanked(info, blank);
>  
>  	if (info->fbops->fb_blank)
>   		ret = info->fbops->fb_blank(blank, info);
> diff --git a/include/linux/fb.h b/include/linux/fb.h
> index 0d86aa31bf8d..1e66fac3124f 100644
> --- a/include/linux/fb.h
> +++ b/include/linux/fb.h
> @@ -137,12 +137,10 @@ struct fb_cursor_user {
>  #define FB_EVENT_GET_CONSOLE_MAP        0x07
>  /*      CONSOLE-SPECIFIC: set console to framebuffer mapping */
>  #define FB_EVENT_SET_CONSOLE_MAP        0x08
> -/*      A hardware display blank change occurred */
> +/*      A display blank is requested       */
>  #define FB_EVENT_BLANK                  0x09
>  /*      Private modelist is to be replaced */
>  #define FB_EVENT_MODE_CHANGE_ALL	0x0B
> -/*	A software display blank change occurred */
> -#define FB_EVENT_CONBLANK               0x0C
>  /*      CONSOLE-SPECIFIC: remap all consoles to new fb - for vga_switcheroo */
>  #define FB_EVENT_REMAP_ALL_CONSOLE      0x0F
>  /*      A hardware display blank early change occurred */
> diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
> index 305e4f2eddac..d67d7ec51ef9 100644
> --- a/include/linux/fbcon.h
> +++ b/include/linux/fbcon.h
> @@ -14,6 +14,7 @@ int fbcon_mode_deleted(struct fb_info *info,
>  void fbcon_new_modelist(struct fb_info *info);
>  void fbcon_get_requirement(struct fb_info *info,
>  			   struct fb_blit_caps *caps);
> +void fbcon_fb_blanked(struct fb_info *info, int blank);
>  #else
>  static inline void fb_console_init(void) {}
>  static inline void fb_console_exit(void) {}
> @@ -27,6 +28,7 @@ static inline int fbcon_mode_deleted(struct fb_info *info,
>  static inline void fbcon_new_modelist(struct fb_info *info) {}
>  static inline void fbcon_get_requirement(struct fb_info *info,
>  					 struct fb_blit_caps *caps) {}
> +static inline void fbcon_fb_blanked(struct fb_info *info, int blank) {}
>  #endif
>  
>  #endif /* _LINUX_FBCON_H */
> -- 
> 2.20.1
> 

Re: [PATCH 24/33] Revert "backlight/fbcon: Add FB_EVENT_CONBLANK"

[Daniel Vetter]

Hi Daniel,

On Fri, May 24, 2019 at 3:14 PM Daniel Thompson
<daniel.thompson@linaro.org> wrote:
>
> On Fri, May 24, 2019 at 10:53:45AM +0200, Daniel Vetter wrote:
> > This reverts commit 994efacdf9a087b52f71e620b58dfa526b0cf928.
> >
> > The justification is that if hw blanking fails (i.e. fbops->fb_blank)
> > fails, then we still want to shut down the backlight. Which is exactly
> > _not_ what fb_blank() does and so rather inconsistent if we end up
> > with different behaviour between fbcon and direct fbdev usage. Given
> > that the entire notifier maze is getting in the way anyway I figured
> > it's simplest to revert this not well justified commit.
> >
> > v2: Add static inline to the dummy version.
> >
> > Cc: Richard Purdie <rpurdie@rpsys.net>
> > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
> > Cc: Lee Jones <lee.jones@linaro.org>
> > Cc: Daniel Thompson <daniel.thompson@linaro.org>
> > Cc: Jingoo Han <jingoohan1@gmail.com>
> > Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Cc: Hans de Goede <hdegoede@redhat.com>
> > Cc: Yisheng Xie <ysxie@foxmail.com>
> > Cc: linux-fbdev@vger.kernel.org
>
> Hi Daniel
>
> When this goes round again could you add me to the covering letter?
>
> I looked at all three of the patches and no objections on my side but
> I'm reluctant to send out acks because I'm not sure I understood the
> wider picture well enough.

It's one of these patch series with some many different subsystems and
people you can't cc the cover to all of them or mailing lists start
rejecting you because too many recipients. I tried to spam sufficient
mailng lists, but I guess not enough.

Cover letter of version one, which tries to explain the full big picture:

https://lists.freedesktop.org/archives/dri-devel/2019-May/218362.html

tldr; I have a multi-year plan to improve fbcon locking, because the
current thing is a bit a mess.

Cover letter of this version, where I detail a bit more the details
fixed in this one here:

https://lists.freedesktop.org/archives/dri-devel/2019-May/218984.html

I can also bounce these to you if you want.

Thanks, Daniel

>
>
> Daniel.
>
>
> > ---
> >  drivers/video/backlight/backlight.c |  2 +-
> >  drivers/video/fbdev/core/fbcon.c    | 14 +-------------
> >  drivers/video/fbdev/core/fbmem.c    |  1 +
> >  include/linux/fb.h                  |  4 +---
> >  include/linux/fbcon.h               |  2 ++
> >  5 files changed, 6 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
> > index deb824bef6e2..c55590ec0057 100644
> > --- a/drivers/video/backlight/backlight.c
> > +++ b/drivers/video/backlight/backlight.c
> > @@ -46,7 +46,7 @@ static int fb_notifier_callback(struct notifier_block *self,
> >       int fb_blank = 0;
> >
> >       /* If we aren't interested in this event, skip it immediately ... */
> > -     if (event != FB_EVENT_BLANK && event != FB_EVENT_CONBLANK)
> > +     if (event != FB_EVENT_BLANK)
> >               return 0;
> >
> >       bd = container_of(self, struct backlight_device, fb_notif);
> > diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
> > index 259cdd118475..d9f545f1a81b 100644
> > --- a/drivers/video/fbdev/core/fbcon.c
> > +++ b/drivers/video/fbdev/core/fbcon.c
> > @@ -2350,8 +2350,6 @@ static int fbcon_switch(struct vc_data *vc)
> >  static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
> >                               int blank)
> >  {
> > -     struct fb_event event;
> > -
> >       if (blank) {
> >               unsigned short charmask = vc->vc_hi_font_mask ?
> >                       0x1ff : 0xff;
> > @@ -2362,13 +2360,6 @@ static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info,
> >               fbcon_clear(vc, 0, 0, vc->vc_rows, vc->vc_cols);
> >               vc->vc_video_erase_char = oldc;
> >       }
> > -
> > -
> > -     lock_fb_info(info);
> > -     event.info = info;
> > -     event.data = &blank;
> > -     fb_notifier_call_chain(FB_EVENT_CONBLANK, &event);
> > -     unlock_fb_info(info);
> >  }
> >
> >  static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
> > @@ -3240,7 +3231,7 @@ int fbcon_fb_registered(struct fb_info *info)
> >       return ret;
> >  }
> >
> > -static void fbcon_fb_blanked(struct fb_info *info, int blank)
> > +void fbcon_fb_blanked(struct fb_info *info, int blank)
> >  {
> >       struct fbcon_ops *ops = info->fbcon_par;
> >       struct vc_data *vc;
> > @@ -3344,9 +3335,6 @@ static int fbcon_event_notify(struct notifier_block *self,
> >               con2fb = event->data;
> >               con2fb->framebuffer = con2fb_map[con2fb->console - 1];
> >               break;
> > -     case FB_EVENT_BLANK:
> > -             fbcon_fb_blanked(info, *(int *)event->data);
> > -             break;
> >       case FB_EVENT_REMAP_ALL_CONSOLE:
> >               idx = info->node;
> >               fbcon_remap_all(idx);
> > diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
> > index ddc0c16b8bbf..9366fbe99a58 100644
> > --- a/drivers/video/fbdev/core/fbmem.c
> > +++ b/drivers/video/fbdev/core/fbmem.c
> > @@ -1068,6 +1068,7 @@ fb_blank(struct fb_info *info, int blank)
> >       event.data = &blank;
> >
> >       early_ret = fb_notifier_call_chain(FB_EARLY_EVENT_BLANK, &event);
> > +     fbcon_fb_blanked(info, blank);
> >
> >       if (info->fbops->fb_blank)
> >               ret = info->fbops->fb_blank(blank, info);
> > diff --git a/include/linux/fb.h b/include/linux/fb.h
> > index 0d86aa31bf8d..1e66fac3124f 100644
> > --- a/include/linux/fb.h
> > +++ b/include/linux/fb.h
> > @@ -137,12 +137,10 @@ struct fb_cursor_user {
> >  #define FB_EVENT_GET_CONSOLE_MAP        0x07
> >  /*      CONSOLE-SPECIFIC: set console to framebuffer mapping */
> >  #define FB_EVENT_SET_CONSOLE_MAP        0x08
> > -/*      A hardware display blank change occurred */
> > +/*      A display blank is requested       */
> >  #define FB_EVENT_BLANK                  0x09
> >  /*      Private modelist is to be replaced */
> >  #define FB_EVENT_MODE_CHANGE_ALL     0x0B
> > -/*   A software display blank change occurred */
> > -#define FB_EVENT_CONBLANK               0x0C
> >  /*      CONSOLE-SPECIFIC: remap all consoles to new fb - for vga_switcheroo */
> >  #define FB_EVENT_REMAP_ALL_CONSOLE      0x0F
> >  /*      A hardware display blank early change occurred */
> > diff --git a/include/linux/fbcon.h b/include/linux/fbcon.h
> > index 305e4f2eddac..d67d7ec51ef9 100644
> > --- a/include/linux/fbcon.h
> > +++ b/include/linux/fbcon.h
> > @@ -14,6 +14,7 @@ int fbcon_mode_deleted(struct fb_info *info,
> >  void fbcon_new_modelist(struct fb_info *info);
> >  void fbcon_get_requirement(struct fb_info *info,
> >                          struct fb_blit_caps *caps);
> > +void fbcon_fb_blanked(struct fb_info *info, int blank);
> >  #else
> >  static inline void fb_console_init(void) {}
> >  static inline void fb_console_exit(void) {}
> > @@ -27,6 +28,7 @@ static inline int fbcon_mode_deleted(struct fb_info *info,
> >  static inline void fbcon_new_modelist(struct fb_info *info) {}
> >  static inline void fbcon_get_requirement(struct fb_info *info,
> >                                        struct fb_blit_caps *caps) {}
> > +static inline void fbcon_fb_blanked(struct fb_info *info, int blank) {}
> >  #endif
> >
> >  #endif /* _LINUX_FBCON_H */
> > --
> > 2.20.1
> >



-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch

Re: [PATCH 24/33] Revert "backlight/fbcon: Add FB_EVENT_CONBLANK"

[Bartlomiej Zolnierkiewicz]

On 5/24/19 5:28 PM, Daniel Vetter wrote:
> Hi Daniel,
> 
> On Fri, May 24, 2019 at 3:14 PM Daniel Thompson
> <daniel.thompson@linaro.org> wrote:
>>
>> On Fri, May 24, 2019 at 10:53:45AM +0200, Daniel Vetter wrote:
>>> This reverts commit 994efacdf9a087b52f71e620b58dfa526b0cf928.
>>>
>>> The justification is that if hw blanking fails (i.e. fbops->fb_blank)
>>> fails, then we still want to shut down the backlight. Which is exactly
>>> _not_ what fb_blank() does and so rather inconsistent if we end up
>>> with different behaviour between fbcon and direct fbdev usage. Given
>>> that the entire notifier maze is getting in the way anyway I figured
>>> it's simplest to revert this not well justified commit.
>>>
>>> v2: Add static inline to the dummy version.
>>>
>>> Cc: Richard Purdie <rpurdie@rpsys.net>
>>> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
>>> Cc: Lee Jones <lee.jones@linaro.org>
>>> Cc: Daniel Thompson <daniel.thompson@linaro.org>
>>> Cc: Jingoo Han <jingoohan1@gmail.com>
>>> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
>>> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
>>> Cc: Hans de Goede <hdegoede@redhat.com>
>>> Cc: Yisheng Xie <ysxie@foxmail.com>
>>> Cc: linux-fbdev@vger.kernel.org
>>
>> Hi Daniel
>>
>> When this goes round again could you add me to the covering letter?
>>
>> I looked at all three of the patches and no objections on my side but
>> I'm reluctant to send out acks because I'm not sure I understood the
>> wider picture well enough.
> 
> It's one of these patch series with some many different subsystems and
> people you can't cc the cover to all of them or mailing lists start
> rejecting you because too many recipients. I tried to spam sufficient
> mailng lists, but I guess not enough.

BTW Not all relevant patches were posted to linux-fbdev and me (i.e.
"[PATCH 05/33] fbdev/sa1100fb: Remove dead code") - I found them on
other mailing lists but it requires some additional work from me to
find / process them. If possible please Cc: linux-fbdev & me on all
patches in the patchset. Thanks!

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

[PATCH 18/33] fbdev: make unregister/unlink functions not fail

[Daniel Vetter]

Except for driver bugs (which we'll catch with a WARN_ON) this is only
to report failures of the new driver taking over the console. There's
nothing the outgoing driver can do about that, and no one ever
bothered to actually look at these return values. So remove them all.

v2: fixup unregister_framebuffer in savagefb, fbtft, ivtvfb, and neofb
drivers, reported by kbuild.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Peter Rosin <peda@axentia.se>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/media/pci/ivtv/ivtvfb.c              |  6 +-
 drivers/staging/fbtft/fbtft-core.c           |  4 +-
 drivers/video/fbdev/core/fbmem.c             | 73 ++++++--------------
 drivers/video/fbdev/neofb.c                  |  9 +--
 drivers/video/fbdev/savage/savagefb_driver.c |  9 +--
 include/linux/fb.h                           |  4 +-
 6 files changed, 31 insertions(+), 74 deletions(-)

diff --git a/drivers/media/pci/ivtv/ivtvfb.c b/drivers/media/pci/ivtv/ivtvfb.c
index cfd21040d0e3..6435c72ff58e 100644
--- a/drivers/media/pci/ivtv/ivtvfb.c
+++ b/drivers/media/pci/ivtv/ivtvfb.c
@@ -1258,11 +1258,7 @@ static int ivtvfb_callback_cleanup(struct device *dev, void *p)
 	struct osd_info *oi = itv->osd_info;
 
 	if (itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT) {
-		if (unregister_framebuffer(&itv->osd_info->ivtvfb_info)) {
-			IVTVFB_WARN("Framebuffer %d is in use, cannot unload\n",
-				       itv->instance);
-			return 0;
-		}
+		unregister_framebuffer(&itv->osd_info->ivtvfb_info);
 		IVTVFB_INFO("Unregister framebuffer %d\n", itv->instance);
 		itv->ivtvfb_restore = NULL;
 		ivtvfb_blank(FB_BLANK_VSYNC_SUSPEND, &oi->ivtvfb_info);
diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index 9b07badf4c6c..7cbc1bdd2d8a 100644
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -891,7 +891,9 @@ int fbtft_unregister_framebuffer(struct fb_info *fb_info)
 	if (par->fbtftops.unregister_backlight)
 		par->fbtftops.unregister_backlight(par);
 	fbtft_sysfs_exit(par);
-	return unregister_framebuffer(fb_info);
+	unregister_framebuffer(fb_info);
+
+	return 0;
 }
 EXPORT_SYMBOL(fbtft_unregister_framebuffer);
 
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c
index f3fc2e5b193c..f3bcad30d3ba 100644
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1590,13 +1590,13 @@ static bool fb_do_apertures_overlap(struct apertures_struct *gena,
 	return false;
 }
 
-static int do_unregister_framebuffer(struct fb_info *fb_info);
+static void do_unregister_framebuffer(struct fb_info *fb_info);
 
 #define VGA_FB_PHYS 0xA0000
-static int do_remove_conflicting_framebuffers(struct apertures_struct *a,
-					      const char *name, bool primary)
+static void do_remove_conflicting_framebuffers(struct apertures_struct *a,
+					       const char *name, bool primary)
 {
-	int i, ret;
+	int i;
 
 	/* check all firmware fbs and kick off if the base addr overlaps */
 	for_each_registered_fb(i) {
@@ -1612,13 +1612,9 @@ static int do_remove_conflicting_framebuffers(struct apertures_struct *a,
 
 			printk(KERN_INFO "fb%d: switching to %s from %s\n",
 			       i, name, registered_fb[i]->fix.id);
-			ret = do_unregister_framebuffer(registered_fb[i]);
-			if (ret)
-				return ret;
+			do_unregister_framebuffer(registered_fb[i]);
 		}
 	}
-
-	return 0;
 }
 
 static bool lockless_register_fb;
@@ -1634,11 +1630,9 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 	if (fb_check_foreignness(fb_info))
 		return -ENOSYS;
 
-	ret = do_remove_conflicting_framebuffers(fb_info->apertures,
-						 fb_info->fix.id,
-						 fb_is_primary_device(fb_info));
-	if (ret)
-		return ret;
+	do_remove_conflicting_framebuffers(fb_info->apertures,
+					   fb_info->fix.id,
+					   fb_is_primary_device(fb_info));
 
 	if (num_registered_fb = FB_MAX)
 		return -ENXIO;
@@ -1714,32 +1708,25 @@ static int do_register_framebuffer(struct fb_info *fb_info)
 	return ret;
 }
 
-static int unbind_console(struct fb_info *fb_info)
+static void unbind_console(struct fb_info *fb_info)
 {
 	int i = fb_info->node;
 
-	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
-		return -EINVAL;
+	if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
+		return;
 
 	console_lock();
 	lock_fb_info(fb_info);
 	fbcon_fb_unbind(fb_info);
 	unlock_fb_info(fb_info);
 	console_unlock();
-
-	return 0;
 }
 
-static int __unlink_framebuffer(struct fb_info *fb_info);
+static void __unlink_framebuffer(struct fb_info *fb_info);
 
-static int do_unregister_framebuffer(struct fb_info *fb_info)
+static void do_unregister_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
-	ret = unbind_console(fb_info);
-
-	if (ret)
-		return -EINVAL;
+	unbind_console(fb_info);
 
 	pm_vt_switch_unregister(fb_info->dev);
 
@@ -1764,36 +1751,27 @@ static int do_unregister_framebuffer(struct fb_info *fb_info)
 
 	/* this may free fb info */
 	put_fb_info(fb_info);
-	return 0;
 }
 
-static int __unlink_framebuffer(struct fb_info *fb_info)
+static void __unlink_framebuffer(struct fb_info *fb_info)
 {
 	int i;
 
 	i = fb_info->node;
-	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
-		return -EINVAL;
+	if (WARN_ON(i < 0 || i >= FB_MAX || registered_fb[i] != fb_info))
+		return;
 
 	if (fb_info->dev) {
 		device_destroy(fb_class, MKDEV(FB_MAJOR, i));
 		fb_info->dev = NULL;
 	}
-
-	return 0;
 }
 
-int unlink_framebuffer(struct fb_info *fb_info)
+void unlink_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
-	ret = __unlink_framebuffer(fb_info);
-	if (ret)
-		return ret;
+	__unlink_framebuffer(fb_info);
 
 	unbind_console(fb_info);
-
-	return 0;
 }
 EXPORT_SYMBOL(unlink_framebuffer);
 
@@ -1810,7 +1788,6 @@ EXPORT_SYMBOL(unlink_framebuffer);
 int remove_conflicting_framebuffers(struct apertures_struct *a,
 				    const char *name, bool primary)
 {
-	int ret;
 	bool do_free = false;
 
 	if (!a) {
@@ -1824,13 +1801,13 @@ int remove_conflicting_framebuffers(struct apertures_struct *a,
 	}
 
 	mutex_lock(&registration_lock);
-	ret = do_remove_conflicting_framebuffers(a, name, primary);
+	do_remove_conflicting_framebuffers(a, name, primary);
 	mutex_unlock(&registration_lock);
 
 	if (do_free)
 		kfree(a);
 
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL(remove_conflicting_framebuffers);
 
@@ -1927,16 +1904,12 @@ EXPORT_SYMBOL(register_framebuffer);
  *      that the driver implements fb_open() and fb_release() to
  *      check that no processes are using the device.
  */
-int
+void
 unregister_framebuffer(struct fb_info *fb_info)
 {
-	int ret;
-
 	mutex_lock(&registration_lock);
-	ret = do_unregister_framebuffer(fb_info);
+	do_unregister_framebuffer(fb_info);
 	mutex_unlock(&registration_lock);
-
-	return ret;
 }
 EXPORT_SYMBOL(unregister_framebuffer);
 
diff --git a/drivers/video/fbdev/neofb.c b/drivers/video/fbdev/neofb.c
index 5d3a444083f7..b770946a0920 100644
--- a/drivers/video/fbdev/neofb.c
+++ b/drivers/video/fbdev/neofb.c
@@ -2122,14 +2122,7 @@ static void neofb_remove(struct pci_dev *dev)
 	DBG("neofb_remove");
 
 	if (info) {
-		/*
-		 * If unregister_framebuffer fails, then
-		 * we will be leaving hooks that could cause
-		 * oopsen laying around.
-		 */
-		if (unregister_framebuffer(info))
-			printk(KERN_WARNING
-			       "neofb: danger danger!  Oopsen imminent!\n");
+		unregister_framebuffer(info);
 
 		neo_unmap_video(info);
 		fb_destroy_modedb(info->monspecs.modedb);
diff --git a/drivers/video/fbdev/savage/savagefb_driver.c b/drivers/video/fbdev/savage/savagefb_driver.c
index 47b78f0138c3..512789f5f884 100644
--- a/drivers/video/fbdev/savage/savagefb_driver.c
+++ b/drivers/video/fbdev/savage/savagefb_driver.c
@@ -2333,14 +2333,7 @@ static void savagefb_remove(struct pci_dev *dev)
 	DBG("savagefb_remove");
 
 	if (info) {
-		/*
-		 * If unregister_framebuffer fails, then
-		 * we will be leaving hooks that could cause
-		 * oopsen laying around.
-		 */
-		if (unregister_framebuffer(info))
-			printk(KERN_WARNING "savagefb: danger danger! "
-			       "Oopsen imminent!\n");
+		unregister_framebuffer(info);
 
 #ifdef CONFIG_FB_SAVAGE_I2C
 		savagefb_delete_i2c_busses(info);
diff --git a/include/linux/fb.h b/include/linux/fb.h
index b6ce041d9e13..b90cf7d56bd8 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -634,8 +634,8 @@ extern ssize_t fb_sys_write(struct fb_info *info, const char __user *buf,
 
 /* drivers/video/fbmem.c */
 extern int register_framebuffer(struct fb_info *fb_info);
-extern int unregister_framebuffer(struct fb_info *fb_info);
-extern int unlink_framebuffer(struct fb_info *fb_info);
+extern void unregister_framebuffer(struct fb_info *fb_info);
+extern void unlink_framebuffer(struct fb_info *fb_info);
 extern int remove_conflicting_pci_framebuffers(struct pci_dev *pdev, int res_id,
 					       const char *name);
 extern int remove_conflicting_framebuffers(struct apertures_struct *a,
-- 
2.20.1