1. 12 Mar, 2010 3 commits
    • Jaya Kumar's avatar
      broadsheetfb: support storing waveform · b32bfc38
      Jaya Kumar authored
      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: default avatarJaya Kumar <jayakumar.lkml@gmail.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      b32bfc38
    • Jaya Kumar's avatar
      broadsheetfb: add MMIO hooks · 2afb1898
      Jaya Kumar authored
      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: default avatarJaya Kumar <jayakumar.lkml@gmail.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2afb1898
    • Jaya Kumar's avatar
      broadsheetfb: add multiple panel type support · c1c341a0
      Jaya Kumar authored
      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: default avatarJaya 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c1c341a0
  2. 10 Feb, 2009 1 commit