summaryrefslogtreecommitdiffstats
path: root/include/linux/fbcon.h
Commit message (Collapse)AuthorAgeFilesLines
* fbcon: Prevent that screen size is smaller than font sizeHelge Deller2022-07-071-0/+4
| | | | | | | | | | | | | | | | We need to prevent that users configure a screen size which is smaller than the currently selected font size. Otherwise rendering chars on the screen will access memory outside the graphics memory region. This patch adds a new function fbcon_modechange_possible() which implements this check and which later may be extended with other checks if necessary. The new function is called from the FBIOPUT_VSCREENINFO ioctl handler in fbmem.c, which will return -EINVAL if userspace asked for a too small screen size. Signed-off-by: Helge Deller <deller@gmx.de> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: stable@vger.kernel.org # v5.4+
* fbcon: Call con2fb_map functions directlyDaniel Vetter2019-06-121-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These are actually fbcon ioctls which just happen to be exposed through /dev/fb*. They completely ignore which fb_info they're called on, and I think the userspace tool even hardcodes to /dev/fb0. Hence just forward the entire thing to fbcon.c wholesale. Note that this patch drops the fb_lock/unlock on the set side. Since the ioctl can operate on any fb (as passed in through con2fb.framebuffer) this is bogus. Also note that fbcon.c in general never calls fb_lock on anything, so this has been badly broken already. With this the last user of the fbcon notifier callback is gone, and we can garbage collect that too. v2: add missing uaccess.h include (alpha fails to compile otherwise), reported by kbuild. v3: Remember to also drop the #defines (Maarten) v4: Add the static inline to dummy functions. 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: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> 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> Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-31-daniel.vetter@ffwll.ch
* vgaswitcheroo: call fbcon_remap_all directlyDaniel Vetter2019-06-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | 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> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-30-daniel.vetter@ffwll.ch
* fbcon: replace FB_EVENT_MODE_CHANGE/_ALL with direct callsDaniel Vetter2019-06-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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. v4: Add missing #include <fbcon.h> to sh_mob (Sam). Cc: Sam Ravnborg <sam@ravnborg.org> 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> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> 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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-29-daniel.vetter@ffwll.ch
* Revert "backlight/fbcon: Add FB_EVENT_CONBLANK"Daniel Vetter2019-06-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> Reviewed-by: Sam Ravnborg <sam@ravnborg.org> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Acked-by: Daniel Thompson <daniel.thompson@linaro.org> 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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-25-daniel.vetter@ffwll.ch
* fbdev: Call fbcon_get_requirement directlyDaniel Vetter2019-06-121-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | 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> 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: 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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-24-daniel.vetter@ffwll.ch
* fbcon: Call fbcon_mode_deleted/new_modelist directlyDaniel Vetter2019-06-121-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> 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: 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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-23-daniel.vetter@ffwll.ch
* fbdev: directly call fbcon_suspended/resumedDaniel Vetter2019-06-121-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | 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> 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: 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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-22-daniel.vetter@ffwll.ch
* fbcon: call fbcon_fb_bind directlyDaniel Vetter2019-06-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | 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> 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: 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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-18-daniel.vetter@ffwll.ch
* fbcon: call fbcon_fb_(un)registered directlyDaniel Vetter2019-06-121-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> 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: 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 Link: https://patchwork.freedesktop.org/patch/msgid/20190528090304.9388-11-daniel.vetter@ffwll.ch
* fbcon: mark dummy functions 'inline'Arnd Bergmann2017-08-071-2/+2
| | | | | | | | | | | | | | | | | The newly introduced fb_console_init/exit declarations have a dummy alternative that is marked 'static' in the header but not inline, leading to a warning whenever the header gets included: In file included from drivers/video/fbdev/core/fbmem.c:35:0: include/linux/fbcon.h:9:13: error: 'fb_console_exit' defined but not used [-Werror=unused-function] This adds the intended 'inline'. Fixes: 6104c37094e7 ("fbcon: Make fbcon a built-time depency for fbdev") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Sean Paul <seanpaul@chromium.org> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
* fbcon: Make fbcon a built-time depency for fbdevDaniel Vetter2017-08-011-0/+12
There's a bunch of folks who're trying to make printk less contended and faster, but there's a problem: printk uses the console_lock, and the console lock has become the BKL for all things fbdev/fbcon, which in turn pulled in half the drm subsystem under that lock. That's awkward. There reasons for that is probably just a historical accident: - fbcon is a runtime option of fbdev, i.e. at runtime you can pick whether your fbdev driver instances are used as kernel consoles. Unfortunately this wasn't implemented with some module option, but through some module loading magic: As long as you don't load fbcon.ko, there's no fbdev console support, but loading it (in any order wrt fbdev drivers) will create console instances for all fbdev drivers. - This was implemented through a notifier chain. fbcon.ko enumerates all fbdev instances at load time and also registers itself as listener in the fbdev notifier. The fbdev core tries to register new fbdev instances with fbcon using the notifier. - On top of that the modifier chain is also used at runtime by the fbdev subsystem to e.g. control backlights for panels. - The problem is that the notifier puts a mutex locking context between fbdev and fbcon, which mixes up the locking contexts for both the runtime usage and the register time usage to notify fbcon. And at runtime fbcon (through the fbdev core) might call into the notifier from a printk critical section while console_lock is held. - This means console_lock must be an outer lock for the entire fbdev subsystem, which also means it must be acquired when registering a new framebuffer driver as the outermost lock since we might call into fbcon (through the notifier) which would result in a locking inversion if fbcon would acquire the console_lock from its notifier callback (which it needs to register the console). - console_lock can be held anywhere, since printk can be called anywhere, and through the above story, plus drm/kms being an fbdev driver, we pull in a shocking amount of locking hiercharchy underneath the console_lock. Which makes cleaning up printk really hard (not even splitting console_lock into an rwsem is all that useful due to this). There's various ways to address this, but the cleanest would be to make fbcon a compile-time option, where fbdev directly calls the fbcon register functions from register_framebuffer, or dummy static inline versions if fbcon is disabled. Maybe augmented with a runtime knob to disable fbcon, if that's needed (for debugging perhaps). But this could break some users who rely on the magic "loading fbcon.ko enables/disables fbdev framebuffers at runtime" thing, even if that's unlikely. Hence we must be careful: 1. Create a compile-time dependency between fbcon and fbdev in the least minimal way. This is what this patch does. 2. Wait at least 1 year to give possible users time to scream about how we broke their setup. Unlikely, since all distros make fbcon compile-in, and embedded platforms only compile stuff they know they need anyway. But still. 3. Convert the notifier to direct functions calls, with dummy static inlines if fbcon is disabled. We'll still need the fb notifier for the other uses (like backlights), but we can probably move it into the fb core (atm it must be built-into vmlinux). 4. Push console_lock down the call-chain, until it is down in console_register again. 5. Finally start to clean up and rework the printk/console locking. For context of this saga see commit 50e244cc793d511b86adea24972f3a7264cae114 Author: Alan Cox <alan@linux.intel.com> Date: Fri Jan 25 10:28:15 2013 +1000 fb: rework locking to fix lock ordering on takeover plus the pile of commits on top that tried to make this all work without terminally upsetting lockdep. We've uncovered all this when console_lock lockdep annotations where added in commit daee779718a319ff9f83e1ba3339334ac650bb22 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Sat Sep 22 19:52:11 2012 +0200 console: implement lockdep support for console_lock On the patch itself: - Switch CONFIG_FRAMEBUFFER_CONSOLE to be a boolean, using the overall CONFIG_FB tristate to decided whether it should be a module or built-in. - At first I thought I could force the build depency with just a dummy symbol that fbcon.ko exports and fb.ko uses. But that leads to a module depency cycle (it works fine when built-in). Since this tight binding is the entire goal the simplest solution is to move all the fbcon modules (and there's a bunch of optinal source-files which are each modules of their own, for no good reason) into the overall fb.ko core module. That's a bit more than what I would have liked to do in this patch, but oh well. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>