| Metronomefb |
| ----------- |
| Maintained by Jaya Kumar <jayakumar.lkml.gmail.com> |
| Last revised: Nov 20, 2007 |
| |
| 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. |
| Currently, that's implemented for the PXA's LCDC controller. The display and |
| error status are each pulled through individual GPIOs. |
| |
| Metronomefb was written for the PXA255/gumstix/lyre combination and |
| therefore currently has board set specific code in it. If other boards based on |
| other architectures are available, then the host specific code can be separated |
| and abstracted out. |
| |
| 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 waveform.wbf |
| which would typically go into /lib/firmware/waveform.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. |
| |
