fbdev/core: Use list_for_each_entry() helper

Convert list_for_each() to list_for_each_entry() so that the pos
list_head pointer and list_entry() call are no longer needed, which
can reduce a few lines of code. No functional changed.

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>

fbdev: modedb: Add 1920x1080 at 60 Hz video mode

Add typical resolution for Full-HD monitors.

Signed-off-by: Helge Deller <deller@gmx.de>

fbdev: Read video= option with fb_get_option() in modedb

Get the kernel's global video= parameter with fb_get_option(). Done
to unexport the internal fbdev state fb_mode_config. 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/20230209135509.7786-6-tzimmermann@suse.de

fbdev: Ditch fb_edid_add_monspecs

It's dead code ever since

commit 34280340b1dc74c521e636f45cd728f9abf56ee2
Author: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Fri Dec 4 17:01:43 2015 +0100

fbdev: Remove unused SH-Mobile HDMI driver

Also with this gone we can remove the cea_modes db. This entire thing
is massively incomplete anyway, compared to the CEA parsing that
drm_edid.c does.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Tavis Ormandy <taviso@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190721201956.941-1-daniel.vetter@ffwll.ch

fbdev: fix divide error in fb_var_to_videomode

To fix following divide-by-zero error found by Syzkaller:

divide error: 0000 [#1] SMP PTI
CPU: 7 PID: 8447 Comm: test Kdump: loaded Not tainted 4.19.24-8.al7.x86_64 #1
Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
RIP: 0010:fb_var_to_videomode+0xae/0xc0
Code: 04 44 03 46 78 03 4e 7c 44 03 46 68 03 4e 70 89 ce d1 ee 69 c0 e8 03 00 00 f6 c2 01 0f 45 ce 83 e2 02 8d 34 09 0f 45 ce 31 d2 <41> f7 f0 31 d2 f7 f1 89 47 08 f3 c3 66 0f 1f 44 00 00 0f 1f 44 00
RSP: 0018:ffffb7e189347bf0 EFLAGS: 00010246
RAX: 00000000e1692410 RBX: ffffb7e189347d60 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb7e189347c10
RBP: ffff99972a091c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000100
R13: 0000000000010000 R14: 00007ffd66baf6d0 R15: 0000000000000000
FS: 00007f2054d11740(0000) GS:ffff99972fbc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f205481fd20 CR3: 00000004288a0001 CR4: 00000000001606a0
Call Trace:
fb_set_var+0x257/0x390
? lookup_fast+0xbb/0x2b0
? fb_open+0xc0/0x140
? chrdev_open+0xa6/0x1a0
do_fb_ioctl+0x445/0x5a0
do_vfs_ioctl+0x92/0x5f0
? __alloc_fd+0x3d/0x160
ksys_ioctl+0x60/0x90
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x5b/0x190
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f20548258d7
Code: 44 00 00 48 8b 05 b9 15 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 15 2d 00 f7 d8 64 89 01 48

It can be triggered easily with following test code:

#include <linux/fb.h>
#include <fcntl.h>
#include <sys/ioctl.h>
int main(void)
{
struct fb_var_screeninfo var = {.activate = 0x100, .pixclock = 60};
int fd = open("/dev/fb0", O_RDWR);
if (fd < 0)
return 1;

if (ioctl(fd, FBIOPUT_VSCREENINFO, &var))
return 1;

return 0;
}

Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Cc: Fredrik Noring <noring@nocrew.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbdev: fix modedb docs in fb_find_mode

Fix up the indenting that confused sphinx. To make sure we
don't have to make the examples unreadable with escaping just
put them in as block quotes, that seems the simplest solution.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[b.zolnierkie: ported over fbdev changes]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbdev: Distinguish between interlaced and progressive modes

I discovered the problem when developing a frame buffer driver for the
PlayStation 2 (not yet merged), using the following video modes for the
PlayStation 3 in drivers/video/fbdev/ps3fb.c:

}, {
/* 1080if */
"1080if", 50, 1920, 1080, 13468, 148, 484, 36, 4, 88, 5,
FB_SYNC_BROADCAST, FB_VMODE_INTERLACED
}, {
/* 1080pf */
"1080pf", 50, 1920, 1080, 6734, 148, 484, 36, 4, 88, 5,
FB_SYNC_BROADCAST, FB_VMODE_NONINTERLACED
},

In ps3fb_probe, the mode_option module parameter is used with fb_find_mode
but it can only select the interlaced variant of 1920x1080 since the loop
matching the modes does not take the difference between interlaced and
progressive modes into account.

In short, without the patch, progressive 1920x1080 cannot be chosen as a
mode_option parameter since fb_find_mode (falsely) thinks interlace is a
perfect match.

Signed-off-by: Fredrik Noring <noring@nocrew.org>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
[b.zolnierkie: updated patch description]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

fbdev: fix cea_modes array size

CEA defines 64 modes, indexed from 1 to 64. modedb has cea_modes arrays,
which contains 64 entries. However, the code uses the CEA indices
directly, i.e. the first mode is at cea_modes[1]. This means the array
is one too short.

This does not cause references to uninitialized memory as the code in
fbmon only allows indexes up to 63, and the cea_modes does not contain
an entry for the mode 64 so it could not be used in any case.

However, the code contains a check 'if (idx > ARRAY_SIZE(cea_modes)',
and while that check is a no-op as at that point idx cannot be >= 63, it
upsets static checkers.

Fix this by increasing the cea_array size to be 65, and change the code
to allow mode 64.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

video: fbdev: Fix sparse warning messages

Use NULL instead of 0 for the last entry of dmt_modes struct.
Supresses "sparse: Using plain integer as NULL pointer" warning.

Signed-off-by: David Ung <davidu@nvidia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

video: fbdev: Check Standard Timing against DMT

Add the VESA Display Monitor Timing (DMT) table.
During parsing of Standard Timings, it compare the 2 byte STD code
with DMT to see what the VESA mode should be. If there is no entry
in the vesa_modes table or no match found, it fallsback to the
GTF timings.

Signed-off-by: David Ung <davidu@nvidia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

video: fbdev: Add additional vesa modes

Add high resolution modes to vesa_modes struct.

Signed-off-by: David Ung <davidu@nvidia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

video/fbdev: Always built-in video= cmdline parsing

In drm/i915 we want to get at the video= cmdline modes even when we
don't have fbdev support enabled, so that users can always override
the kernel's initial mode selection.

But that gives us a direct depency upon the parsing code in the fbdev
subsystem. Since it's so little code just extract these 2 functions
and always build them in.

Whiel at it fix the checkpatch fail in this code.

v2: Also move fb_mode_option. Spotted by the kbuild.

v3: Review from Geert:
- Keep the old copyright notice from fb_mem.c, although I have no
idea what exactly applies.
- Only compile this when needed.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

--

I prefer if we can merge this through drm-next since we'll use it
there in follow-up patches.
-Daniel

fbdev: move fbdev core files to separate directory

Instead of having fbdev framework core files at the root fbdev
directory, mixed with random fbdev device drivers, move the fbdev core
files to a separate core directory. This makes it much clearer which of
the files are actually part of the fbdev framework, and which are part
of device drivers.

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>