Commit Graph

5 Commits

Author SHA1 Message Date
Jaya Kumar b32bfc3843 broadsheetfb: support storing waveform
This patch adds waveform storing capability to broadsheetfb. It uses the
firmware class to retrieve the waveform, and the request to initiate the
waveform storing is done via a driver sysfs entry, loadstore_waveform.

Broadsheet is a framebuffer device.  It is slightly different from a
typical framebuffer controller that drives a normal TFT-LCD display.  Most
E-Ink display panels require a waveform in order to function.  That is, in
order to drive the state of a pixel to black, gray, or white, a specific
waveform is utilized.  Basically, that waveform represents the specific
E-field wiggling needed to get the pixel to its optimal state given
current temperature, and its previous state.  TN/IPS-LCDs use a similar
concept but the driving waveform is sufficiently simple that it is
internalized in the TFT source/gate driver.

These E-Ink waveforms are specific to a production batch.  That is, a
batch of display films are produced, then they get characterized and a
waveform is generated for that batch.  Broadsheet, typically, is attached
to its private SPI flash which is then flashed with this waveform.

Users won't be able to see the waveform and typically won't ever need to
know about it.  If however, the display panel attached to broadsheet is
changed out, then they will need to update their waveform.  That would
typically be done at a factory or repair facility rather than by a user.

[akpm@linux-foundation.org: fix printk warning]
Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:34 -08:00
Jaya Kumar 2afb189817 broadsheetfb: add MMIO hooks
Allow boards with GP-MMIO controllers to provide hooks to broadsheetfb in
order to offload cmd/data writes and data reads instead of relying only on
host based GPIO wiggling.

Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:34 -08:00
Jaya Kumar c1c341a060 broadsheetfb: add multiple panel type support
Update broadsheetfb to add support for multiple panel types.  The 3.7" and
6" are known to work but the 9.7" is untested due to lack of hardware.

Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:32 -08:00
Konrad Rzeszutek Wilk a9b5ff99c3 fb-defio: Inhibit VM_IO flag to be set on vmalloc-ed framebuffers.
The framebuffers (screenbase) these drivers present are actually
vmalloc-ed pages. There is no need for them to have the VM_IO flag set.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Jaya Kumar <jayakumar.lkml@gmail.com>
2009-12-03 17:30:42 -08:00
Jaya Kumar 0d4ff4df34 [ARM] 5353/1: fbdev: add E-Ink Broadsheet controller support v3
This patch adds support for the E-Ink Broadsheet display controller.

Cc: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-10 11:27:59 +00:00