Fri, 04 Mar 2011
WM8505 state of play - March 2011
Hardware noteA number of WM8505 netbooks have a hardware bug where the sense line of the MMC/SD slot's write protect switch is reversed. These will sense unprotected SD cards as protected and vice versa. You will not be able to live-boot Bento Linux from a write-protected SD; it will hang when trying to mount the root filesystem, and consequently not load the framebuffer driver, and nothing will appear to happen.
Bento LinuxBento was released with a kernel stolen from an Android device, as that was the only way to get Linux running initially on the 8505 devices. Now that the source has been released, we can change the shortcomings of this kernel, namely compiling in framebuffer console, and removing the Android security model code. Nobody has done this yet (and rereleased the bento fatpart).
VIA's source releaseVIA released some source code for these tablets. A slightly cleaned-up version of the VIA tree has been published by Angus Gratton here. This needs configuring to work properly. Key variable for video is GE_BUFFER_SIZE or similar. A working config is available here (for netbook).
Open source reimplementationA completely open-source effort is underway to get a WM850x port into Linux mainline. This port is spearheaded by Alexey Charkov; its base is here. At this point, in addition to basic booting and serial, it supports video, RTC, keyboard. Tony Prisk has been working on MMC/SD patches, and there are also Ethernet support patches on the mailing list.
Development discussion takes place on a mailing list (here) - this group is for development discussion, not help requests, please!
HelpThe most active place for general help seems to be
posted at: 15:19 | path: /linux/wm8505 | permanent link to this entry