0001 ===========
0002 Metronomefb
0003 ===========
0004
0005 Maintained by Jaya Kumar <jayakumar.lkml.gmail.com>
0006
0007 Last revised: Mar 10, 2008
0008
0009 Metronomefb is a driver for the Metronome display controller. The controller
0010 is from E-Ink Corporation. It is intended to be used to drive the E-Ink
0011 Vizplex display media. E-Ink hosts some details of this controller and the
0012 display media here http://www.e-ink.com/products/matrix/metronome.html .
0013
0014 Metronome is interfaced to the host CPU through the AMLCD interface. The
0015 host CPU generates the control information and the image in a framebuffer
0016 which is then delivered to the AMLCD interface by a host specific method.
0017 The display and error status are each pulled through individual GPIOs.
0018
0019 Metronomefb is platform independent and depends on a board specific driver
0020 to do all physical IO work. Currently, an example is implemented for the
0021 PXA board used in the AM-200 EPD devkit. This example is am200epd.c
0022
0023 Metronomefb requires waveform information which is delivered via the AMLCD
0024 interface to the metronome controller. The waveform information is expected to
0025 be delivered from userspace via the firmware class interface. The waveform file
0026 can be compressed as long as your udev or hotplug script is aware of the need
0027 to uncompress it before delivering it. metronomefb will ask for metronome.wbf
0028 which would typically go into /lib/firmware/metronome.wbf depending on your
0029 udev/hotplug setup. I have only tested with a single waveform file which was
0030 originally labeled 23P01201_60_WT0107_MTC. I do not know what it stands for.
0031 Caution should be exercised when manipulating the waveform as there may be
0032 a possibility that it could have some permanent effects on the display media.
0033 I neither have access to nor know exactly what the waveform does in terms of
0034 the physical media.
0035
0036 Metronomefb uses the deferred IO interface so that it can provide a memory
0037 mappable frame buffer. It has been tested with tinyx (Xfbdev). It is known
0038 to work at this time with xeyes, xclock, xloadimage, xpdf.
