Monday, August 16, 2010

Week 12 report

Report for the week  09-8-10 to 16-8-10

I was busy this week with some urgent college work, so could not put in as much time.

* Improved the documentation on the elinux wiki page.

* Made a patch and submitted it to the linux-omap mailing list for review. I sent in the patch this morning so am still waiting for some opinions about it. I am hoping I have got the basics right.

* I will try and put some more time into testing the pwm speaker driver.

Monday, August 9, 2010

Week 11 report

Report for the week  02-8-10 to 09-8-10

* I misunderstood the ioctl() interface thinking that I could issue these calls from the kernel space as well. But later discovered that these can only be used from the userspace. This was causing the compile errors I mentioned in the last week's report. With this out of the way I can now build the pwm speaker driver.

* The pwm driver can now be used even in the kernel space with the addition of some EXPORT_SYMBOL() commands. Not all of the features are available through this right now but I will look into this.

* I have been testing the pwm speaker driver with not a lot of success but hopefully it will get fixed this week.

* Improve the documentation on the wiki as well as the repo.

Monday, August 2, 2010

Week 10 report

Report for the week  26-7-10 to 02-8-10

* I managed to modify the pcsp driver (/usr/src/linux/drivers/pcsp). It works through two files pcsp.c and pcsp_lib.c. The first one mainly initialises the alsa device and does more or less book keeping work. The second file accesses pcm data from the dma region  and sets up pwm signal correspondingly as Hunyue pointed before. There is also a lot of stuff for accessing the hardware timers which I have stripped out.
I am having some compiling problems right now using this makefile ( ) and, these files pwmsp.c(  and pwmsp_lib.c ( ). It gives me these errors .

After fixing these compiling errors, I will test this driver and make a demo for this.