fbdev: offb: Simplify offb_init_fb()

Turn a strcpy()+strncat()+'\0' into an equivalent snprintf().

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Helge Deller <deller@gmx.de>

fbdev/offb: Use fbdev I/O helpers

Set struct fb_ops and with FB_DEFAULT_IOMEM_OPS, fbdev's initializer
for I/O memory. Sets the callbacks to the cfb_ and fb_io_ functions.
Select the correct modules with Kconfig's FB_IOMEM_HELPERS token.

The macro and token set the currently selected values, so there is
no functional change.

v3:
* use _IOMEM_ in commit message
v2:
* updated to use _IOMEM_ tokens

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230803184034.6456-29-tzimmermann@suse.de

fbdev: Remove FBINFO_DEFAULT from framebuffer_alloc()'ed structs

The flag FBINFO_DEFAULT is 0 and has no effect, as struct fbinfo.flags
has been allocated to zero by framebuffer_alloc(). So do not set it.

Flags should signal differences from the default values. After cleaning
up all occurrences of FBINFO_DEFAULT, the token will be removed.

v4:
* clarify commit message (Geert, Dan)
v2:
* fix commit message (Miguel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ferenc Bakonyi <fero@drama.obuda.kando.hu>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Antonino Daplas <adaplas@gmail.com>
Cc: Maik Broemme <mbroemme@libmpq.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Kristoffer Ericson <kristoffer.ericson@gmail.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Steve Glendinning <steve.glendinning@shawell.net>
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230715185343.7193-6-tzimmermann@suse.de

fbdev: offb: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Helge Deller <deller@gmx.de>

fbdev: Use of_property_read_bool() for boolean properties

It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties.
Convert reading boolean properties to to of_property_read_bool().

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>

fbdev/offb: Do not use struct fb_info.apertures

Acquire ownership of the firmware scanout buffer by calling Linux'
aperture helpers. Remove the use of struct fb_info.apertures and do
not set FBINFO_MISC_FIRMWARE; both of which previously configured
buffer ownership.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219160516.23436-14-tzimmermann@suse.de

fbdev/offb: Allocate struct offb_par with framebuffer_alloc()

Move the palette array into struct offb_par and allocate both via
framebuffer_alloc(), as intended by fbdev. No functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221219160516.23436-13-tzimmermann@suse.de

video: fbdev: offb: Include missing linux/platform_device.h

A lot of drivers were getting platform and of headers
indirectly via headers like asm/pci.h or asm/prom.h

Most of them were fixed during 5.19 cycle but a newissue was
introduced by commit 52b1b46c39ae ("of: Create platform devices
for OF framebuffers")

Include missing platform_device.h to allow cleaning asm/pci.h

Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f75b383673663e27f6b57e50b4abfb9fe3780b00.1657264228.git.christophe.leroy@csgroup.eu

of: Create platform devices for OF framebuffers

Create a platform device for each OF-declared framebuffer and have
offb bind to these devices. Allows for real hot-unplugging and other
drivers besides offb.

Originally, offb created framebuffer devices while initializing its
module by parsing the OF device tree. No actual Linux device was set
up. This tied OF framebuffers to offb and makes writing other drivers
for the OF framebuffers complicated. The absence of a Linux device
further prevented real hot-unplugging. Adding a distinct platform
device for each OF framebuffer solves both problems. Specifically, a
DRM driver can now provide graphics output for modern userspace.

Some of the offb init code is now located in the OF initialization.
There's now also an implementation of of_platform_default_populate_init(),
which was missing before. The OF side creates different devices for
either OF display nodes or BootX displays as they require different
handling by the driver. The offb drivers picks up each type of device
and runs the appropriate fbdev initialization.

Tested with OF display nodes on qemu's ppc64le target.

v3:
* declare variable 'node' with function scope (Rob)
v2:
* run PPC code as part of existing initialization (Rob)
* add a few more error warnings (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220419100405.12600-2-tzimmermann@suse.de

video: fbdev: offb: fix warning comparing pointer to 0

Fix the following coccicheck warning:
drivers/video/fbdev/offb.c:415:13-14: WARNING comparing pointer to 0

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Signed-off-by: Helge Deller <deller@gmx.de>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

fbdev: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200707210539.GA12530@embeddedor

video: constify fb ops across all drivers

Now that the fbops member of struct fb_info is const, we can start
making the ops const as well.

This does not cover all drivers; some actually modify the fbops struct,
for example to adjust for different configurations, and others do more
involved things that I'd rather not touch in practically obsolete
drivers. Mostly this is the low hanging fruit where we can add "const"
and be done with it.

v3:
- un-constify atyfb, mb862xx, nvidia and uvesabf (0day)

v2:
- fix typo (Christophe de Dinechin)
- use "static const" instead of "const static" in mx3fb.c
- also constify smscufx.c

Cc: linux-fbdev@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ce67f14435f3af498f2e8bf35ce4be11f7504132.1575390740.git.jani.nikula@intel.com

video: offb: annotate implicit fall throughs

There is a plan to build the kernel with -Wimplicit-fallthrough and
these places in the code produced warnings (W=1). Fix them up.

This commit remove the following warnings:

drivers/video/fbdev/offb.c:211:5: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/video/fbdev/offb.c:142:3: warning: this statement may fall through [-Wimplicit-fallthrough=]

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbdev: Use of_node_name_eq for node name comparisons

Convert string compares of DT node names to use of_node_name_eq helper
instead. This removes direct access to the node name pointer.

For instances using of_node_cmp, this has the side effect of now using
case sensitive comparisons. This should not matter for any FDT based
system which omap is.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbdev: offb: Fix OF node name handling

Commit 5c63e407aaab ("fbdev: Convert to using %pOFn instead of
device_node.name") changed how the OF FB driver handles the OF node
name. This missed the case where the node name is passed to
offb_init_palette_hacks(). This results in a NULL ptr dereference
in strncmp and breaks any system except ones using bootx with no display
node.

Fix this by making offb_init_palette_hacks() use the OF node pointer and
use of_node_name_prefix() helper function instead for node name
comparisons. This helps in moving all OF node name accesses to helper
functions in preparation to remove struct device_node.name pointer.

Fixes: 5c63e407aaab ("fbdev: Convert to using %pOFn instead of device_node.name")
Reported-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Mathieu Malaterre <malat@debian.org>
Cc: stable@vger.kernel.org # v4.19+
Cc: Elimar Riesebieter <riesebie@lxtec.de>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbdev: Convert to using %pOFn instead of device_node.name

In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

video: offb: Deallocate the color map

The function offb_destroy did not deallocate the color map leaving some
memory around after destruction. Call the color map deallocate function to
remove the memory leak.

Handle another case where color map should have been deallocated during an
error code path.

Fix memory leaks reported by kmemleak:

# dmesg
...
[ 1884.719941] kmemleak: 3 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
# cat /sys/kernel/debug/kmemleak
unreferenced object 0xde3d9000 (size 512):
comm "swapper", pid 1, jiffies 4294892827 (age 1906.784s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 aa aa aa aa aa aa aa aa ................
55 55 55 55 55 55 55 55 ff ff ff ff ff ff ff ff UUUUUUUU........
backtrace:
[<f1433400>] fb_alloc_cmap_gfp+0x54/0x15c
[<cb6b409b>] offb_init_nodriver+0x8e8/0xa3c
[<b5a1c019>] offb_init+0xd0/0x164
[<322f82a3>] do_one_initcall+0x4c/0x178
[<b592db9f>] kernel_init_freeable+0x138/0x1cc
[<2a17fa0e>] kernel_init+0x24/0x118
[<4079749a>] ret_from_kernel_thread+0x5c/0x64
unreferenced object 0xde3d9200 (size 512):
comm "swapper", pid 1, jiffies 4294892827 (age 1906.784s)
hex dump (first 32 bytes):
00 00 00 00 aa aa aa aa 00 00 00 00 55 55 aa aa ............UU..
55 55 55 55 ff ff ff ff 55 55 55 55 ff ff ff ff UUUU....UUUU....
backtrace:
[<4bf3594d>] fb_alloc_cmap_gfp+0x6c/0x15c
[<cb6b409b>] offb_init_nodriver+0x8e8/0xa3c
[<b5a1c019>] offb_init+0xd0/0x164
[<322f82a3>] do_one_initcall+0x4c/0x178
[<b592db9f>] kernel_init_freeable+0x138/0x1cc
[<2a17fa0e>] kernel_init+0x24/0x118
[<4079749a>] ret_from_kernel_thread+0x5c/0x64
unreferenced object 0xde3d9600 (size 512):
comm "swapper", pid 1, jiffies 4294892827 (age 1906.784s)
hex dump (first 32 bytes):
00 00 aa aa 00 00 aa aa 00 00 aa aa 00 00 aa aa ................
55 55 ff ff 55 55 ff ff 55 55 ff ff 55 55 ff ff UU..UU..UU..UU..
backtrace:
[<23a3ea03>] fb_alloc_cmap_gfp+0x84/0x15c
[<cb6b409b>] offb_init_nodriver+0x8e8/0xa3c
[<b5a1c019>] offb_init+0xd0/0x164
[<322f82a3>] do_one_initcall+0x4c/0x178
[<b592db9f>] kernel_init_freeable+0x138/0x1cc
[<2a17fa0e>] kernel_init+0x24/0x118
[<4079749a>] ret_from_kernel_thread+0x5c/0x64

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

video: fbdev: Convert to using %pOF instead of full_name

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

video: fbdev: offb: switch to using for_each_node_by_type

Instead of open-coding loops let's switch to a nice macro.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

video: fbdev: offb: Call pci_enable_device() before using the PCI VGA device

Currently the offb module will use the PCI VGA device as frame
buffer device without calling something like pci_enable_device().
However, this would cause some problem if we disable memory
decoding of the upstream bridge before. When the console driver
issued memory access to the VGA device, the access cannot be
supported by the bridge which will cause EEH error on Power machine.

Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

PCI: Remove includes of asm/pci-bridge.h

Drivers should include asm/pci-bridge.h only when they need the arch-
specific things provided there. Outside of the arch/ directories, the only
drivers that actually need things provided by asm/pci-bridge.h are the
powerpc RPA hotplug drivers in drivers/pci/hotplug/rpa*.

Remove the includes of asm/pci-bridge.h from the other drivers, adding an
include of linux/pci.h if necessary.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Revert "offb: Add palette hack for little endian"

This reverts commit e1edf18b20076da83dd231dbd2146cbbc31c0b14.

This patch was a misguided attempt at fixing offb for LE ppc64
kernels on BE qemu but is just wrong ... it breaks real LE/LE
setups, LE with real HW, and existing mixed endian systems
that did the fight thing with the appropriate device-tree
property. Bad reviewing on my part, sorry.

The right fix is to either make qemu change its endian when
the guest changes endian (working on that) or to use the
existing foreign endian support.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org> [v3.13+]
---

video: move fbdev to drivers/video/fbdev

The drivers/video directory is a mess. It contains generic video related
files, directories for backlight, console, linux logo, lots of fbdev
device drivers, fbdev framework files.

Make some order into the chaos by creating drivers/video/fbdev
directory, and move all fbdev related files there.

No functionality is changed, although I guess it is possible that some
subtle Makefile build order related issue could be created by this
patch.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>