Re: Frame buffer use on Coldfire problem
On Wed, 19 Dec 2007, email@example.com wrote:
> I'm running a 2.6.10 kernel on a Coldfire (M5484) and I'm trying to
> get some frame buffer graphics going. The video chip I'm using is a
> Epson S1D13a04 and there was actually a driver for Linux kernel 2.6.8
> from Epson that I was able to port to my kernel. Thought life was good
> but I have yet to get anything on the screen at all. My first attempt
> is listed below. The problem occurs on the memory map (mmap) command.
> Thought the /dev/fb0 device opens and the call to ioctl returns valid
> information, when I call mmap to set up the memory the call fails
> (returns -1). The device resides at physical address 0x44040000.
> screensize = vinfo.xres * vinfo.yres * vinfo.bits_per_pixel / 8;
> fbp = mmap((caddr_t)0, screensize, PROT_READ|PROT_WRITE, MAP_SHARED,
> fbfd, 0);
I guess it fails because screensize is not a multiple of the page size?
For testing frame buffer devices, you can always try fbtest (CVS module
FBdev/utlilities/fbtest (yes, spelling typo in the path name ;-) from
project linux-fbdev.sf.net, cfr.
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- firstname.lastname@example.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds