This patch series implements generic code to rotate the console at 90, 180,
and 270 degrees. The implementation is completely done in the framebuffer
console level, thus no changes to the framebuffer layer or to the drivers
are needed.
Console rotation is required by some Sharp-based devices where the natural
orientation of the display is not at 0 degrees. Also, users that have
displays that can pivot will benefit by having a console in portrait mode
if they so desire.
The choice to implement the code in the console layer rather than in the
framebuffer layer is due to the following reasons:
- it's fast
- it does not require driver changes
- it can coexist with devices that can rotate the display at the hardware level
- it complements graphics applications that can do display rotation
The changes to core fbcon are minimal-- recognition of the console
rotation angle so it can swap directions, origins and axes (xres vs yres,
xpanstep vs ypanstep, xoffset vs yoffset, etc) and storage of the rotation
angle per display. The bulk of the code that does the actual drawing to the
screen are placed in separate files. Each angle of rotation has separate
methods (bmove, clear, putcs, cursor, update_start which is derived from
update_var, and clear_margins). To mimimize processing time, the fontdata
are pre-rotated at each console switch (only if the font or the angle has
changed).
The option can be compiled out (CONFIG_FRAMEBUFFER_CONSOLE_ROTATION = n) if
rotation is not needed.
Choosing the rotation angle can be done in several ways:
1. boot option fbcon=rotate:n, where
n = 0 - normal
n = 1 - 90 degrees (clockwise)
n = 2 - 180 degrees (upside down)
n = 3 - 270 degrees (counterclockwise)
2. echo n > /sys/class/graphics/fb[num]/con_rotate
where n is the same as described above. It sets the angle of rotation
of the current console
3 echo n > /sys/class/graphics/fb[num]/con_rotate_all
where n is the same as described above. Globally sets the angle of
rotation.
GOTCHAS:
The option, especially at angles of 90 and 270 degrees, will exercise
the least used code of drivers. Namely, at these angles, panning is done
in the x-axis, so it can reveal bugs in the driver if xpanstep is set
incorrectly. A workaround is to set xpanstep = 0.
Secondly, at these angles, the framebuffer memory access can be
unaligned if (fontheight * bpp) % 32 ~= 0 which can reveal bugs in the drivers
imageblit, fillrect and copyarea functions. (I think cfbfillrect may have
this buglet). A workaround is to use a standard 8x16 font.
Speed:
The scrolling speed difference between 0 and 180 degrees is minimal,
somewhere areound 1-2%. At 90 or 270 degress, speed drops down to a vicinity
of 30-40%. This is understandable because the blit direction is across the
framebuffer "direction." Scrolling will be helped at these angles if xpanstep
is not equal to zero, use of 8x16 fonts, and setting xres_virtual >= xres * 2.
Note: The code is tested on little-endian only, so I don't know if it will
work in big-endian. Please let me know, it will take only less than a minute
of your time.
This patch prepares fbcon for console rotation and contains the following
changes:
- add rotate field in struct fbcon_ops to keep fbcon's current rotation
angle
- add con_rotate field in struct display to store per-display rotation angle
- create a private copy of the current var to fbcon. This will prevent
fbcon from directly manipulating info->var, especially the fields xoffset,
yoffset and vmode.
- add ability to swap pertinent axes (xres, yres; xpanstep, ypanstep; etc)
depending on the rotation angle
- change global update_var() (function that sets the screen start address)
as an fbcon method update_start. This is required because the axes, start
offset, and/or direction can be reversed depending on the rotation angle.
- add fbcon method rotate_font() which will rotate each character bitmap to
the correct angle of rotation.
- add fbcon boot option 'rotate' to select the angle of rotation at bootime.
Currently does nothing until all patches are applied.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently the fb_find_nearest_mode() function finds a mode with screen
resolution closest to that described by the 'var' argument and with some
arbitrary refresh rate (eg. in the following sequence of refresh rates: 70 60
53 85 75, 53 is selected).
This patch fixes the function so that it looks for the closest mode as far as
both resolution and refresh rate are concerned. The function's first argument
is changed to fb_videomode so that the refresh rate can be specified by the
caller, as fb_var_screeninfo doesn't have any fields that could directly hold
this data.
Signed-off-by: Michal Januszewski <spock@gentoo.org>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If machine has more than 1 driver installed, and they all drive the same
hardware, it's possible that the driver's fb_release() method will attempt to
restore the hardware state to the initial state. This will leave the new
driver in an undefined state. To prevent this problem, initialize the new
driver by calling fb_set_par() when the old driver is released by fbcon.
Signed-off-by: Antonino Daplas<adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Instead of manually filling up the fields in struct fb_var_screeninfo, use the
display_to_var() helper.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Lot's of redundant code scattered throughout fbcon.c. Consolidate them all
into one function, fbcon_update_softback().
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
const-ify the font control structures and data, to make somewhat better
guarantees that these are not modified anywhere in the kernel.
Specifically for a kernel debugger to share this information from the
normal kernel code, such a guarantee seems rather desirable.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: "Antonino A. Daplas" <adaplas@hotpop.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
An adjustment to the SM_DOWN case of fbcon_scroll to match the behavior of
SM_UP.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: "Antonino A. Daplas" <adaplas@hotpop.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If console is blanked or in KD_GRAPHICS mode, delete cursor timer. No sense
flashing the cursor when there's nothing to be seen.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently, the default linux 16-colors are converted to 4-colors by simply
dividing the values by 4. However, this is not necessarily correct since the
first 4 colors are converted to black, rendering them invisible.
So, for black, no conversion; for light colors, convert to gray, for normal
text color, no conversion, and for bright colors, convert to intense white.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently, fbcon assumes that the visual FB_VISUAL_MONO* is always 1 bit.
According to Geert, there are old hardware where it's possible to have
monochrome at 8-bit, but has only 2 colors, black - 0x00 and white - 0xff.
Fix color handlers (fb_get_color_depth, and get_color) for this special case.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add capability to fbdev to listen to the FB_ACTIVATE_ALL flag. If set, it
notifies fbcon that all consoles must be set to the current var.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently even when the cursor is disabled (`setterm -cursor off`), it is
still repainted as a black rectangle the size of a single char. This can
be seen, for example, by chvt'ing to a free tty, disabling the cursor and
doing `dd if=3D/dev/urandom of=3D/dev/fb0`.
The patch changes this behaviour by avoiding painting anything when the
cursor is disabled.
Signed-off-by: Michal Januszewski <spock@gentoo.org>
Cc: <linux-fbdev-devel@lists.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The generic fbcon code tries to register and use the vsync IRQ for
ARM platforms with acornfb, but forgets to disable its own cursor
timer. The result is a flickering flashing cursor.
Remove the code from the fbcon core to register this platform
private interrupt.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes a check after use found by the Coverity checker.
Signed-off-by: Adrian Bunk <bunk@fs.tum.de>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
