Project name and homepage: Linux kernel
Assignment
Solve strange bugs affecting Linux user experience on Hewlett-Packard iPAQ hx4700 Pocket PC. First bug, that was affecting touchscreen and SD card reader revolved around voltage regulator API, namely the removal of so called REGULATOR_DUMMY configuration option, is already resolved and patch accepted to mainline kernel.
Subsequent response from the device maintainer
Another bug prevents me from properly setting the maximum clock frequency of Intel XScale PXA27x processor. There is a kernel module called pxa2xx-cpufreq and it accepts pxa27x_maxfreq parameter, that should server that purpose, however, for some reason not yet known to me this parameter gets “consumed” along the way and it is not parsed by the module and this error message can be found in the kernel log:
PXA CPU 27x max frequency not defined (pxa27x_maxfreq), assuming pxa271 with 416000kHz maxfreq
EDIT: This is not in fact a bug. The parameter should be passed on the kernel line like this “pxa2xx-cpufreq.pxa27x_maxfreq=624”, because pxa2xx-cpufreq is a module.
- My communication with developers in a public mailing list archive
- Version control repository with the actual state of my work
- My commit in the project repository
Second try for a patch
I found out, that the HP ProBook 440 G3 laptop incorporates ST LIS3LV02DL accelerometer and there is a module called “hp_accel”, that makes the accelerometer appear as a joystick device, so it could be used to play games like ExtremeTuxRacer. Unfortunately on this specific laptop model, the sensor is soldered upside down on the PCB, so I needed to swap the axis accordingly. The patch has been merged into mainline kernel.
- My communication with developers in a public mailing list archive
- Patch queued up for mainline in Darren Hart’s tree
- Merge from Darren Hart’s tree into mainline
- My commit in the project repository
Presentation
OpenHub