Diffstat (limited to 'Documentation/fb/metronomefb.txt')
1 files changed, 36 insertions, 0 deletions
diff --git a/Documentation/fb/metronomefb.txt b/Documentation/fb/metronomefb.txt
new file mode 100644
@@ -0,0 +1,36 @@
+Maintained by Jaya Kumar <jayakumar.lkml.gmail.com>
+Last revised: Mar 10, 2008
+Metronomefb is a driver for the Metronome display controller. The controller
+is from E-Ink Corporation. It is intended to be used to drive the E-Ink
+Vizplex display media. E-Ink hosts some details of this controller and the
+display media here http://www.e-ink.com/products/matrix/metronome.html .
+Metronome is interfaced to the host CPU through the AMLCD interface. The
+host CPU generates the control information and the image in a framebuffer
+which is then delivered to the AMLCD interface by a host specific method.
+The display and error status are each pulled through individual GPIOs.
+Metronomefb is platform independent and depends on a board specific driver
+to do all physical IO work. Currently, an example is implemented for the
+PXA board used in the AM-200 EPD devkit. This example is am200epd.c
+Metronomefb requires waveform information which is delivered via the AMLCD
+interface to the metronome controller. The waveform information is expected to
+be delivered from userspace via the firmware class interface. The waveform file
+can be compressed as long as your udev or hotplug script is aware of the need
+to uncompress it before delivering it. metronomefb will ask for metronome.wbf
+which would typically go into /lib/firmware/metronome.wbf depending on your
+udev/hotplug setup. I have only tested with a single waveform file which was
+originally labeled 23P01201_60_WT0107_MTC. I do not know what it stands for.
+Caution should be exercised when manipulating the waveform as there may be
+a possibility that it could have some permanent effects on the display media.
+I neither have access to nor know exactly what the waveform does in terms of
+the physical media.
+Metronomefb uses the deferred IO interface so that it can provide a memory
+mappable frame buffer. It has been tested with tinyx (Xfbdev). It is known
+to work at this time with xeyes, xclock, xloadimage, xpdf.