diff options
Diffstat (limited to 'fb.c')
| -rw-r--r-- | fb.c | 96 |
1 files changed, 96 insertions, 0 deletions
@@ -0,0 +1,96 @@ +#include <fcntl.h> +#include <stdio.h> +#include <sys/mman.h> +#include <unistd.h> + +#include <linux/fb.h> +#include <sys/ioctl.h> + +#include "fb.h" +#include "gpio.h" + +struct imx_epdc_fb_mode { + struct fb_videomode *vmode; + int vscan_holdoff; + int sdoed_width; + int sdoed_delay; + int sdoez_width; + int sdoez_delay; + int gdclk_hp_offs; + int gdsp_offs; + int gdoe_offs; + int gdclk_offs; + int num_ce; +}; + +static char *fbaddr; + +void dumpsi(const char *ctl, int io, struct fb_var_screeninfo *si) +{ + printf("- %s\n", ctl); + printf("\tioctl returned %d\n", io); + printf("\txres: %d\n", si->xres); + printf("\tyres: %d\n", si->yres); + printf("\txres_virtual: %d\n", si->xres_virtual); + printf("\tyres_virtual: %d\n", si->yres_virtual); + printf("\txoffset: %d\n", si->xoffset); + printf("\tyoffset: %d\n", si->yoffset); + printf("\tbits_per_pixel: %d\n", si->bits_per_pixel); + printf("\tgrayscale: %d\n", si->grayscale); +} + +void dumpfsi(const char *ctl, int io, struct fb_fix_screeninfo *fsi) +{ + printf("- %s\n", ctl); + printf("\tioctl returned %d\n", io); + printf("\tid: %16s\n", fsi->id); + printf("\tsmem_len: %d\n", fsi->smem_len); + printf("\ttype: %d\n", fsi->type); + printf("\ttype_aux: %d\n", fsi->type_aux); + printf("\tvisual: %d\n", fsi->visual); + printf("\txpanstep: %d\n", fsi->xpanstep); + printf("\typanstep: %d\n", fsi->ypanstep); + printf("\tywrapstep: %d\n", fsi->ywrapstep); + printf("\tline_length: %d\n", fsi->line_length); + printf("\tmmio_start: %lu\n", fsi->mmio_start); + printf("\tmmio_len: %d\n", fsi->mmio_len); + printf("\taccel: %d\n", fsi->accel); + printf("\tcapabilities: %d\n", fsi->capabilities); +} + +void fb_init(void) +{ + printf("enabling left display\n"); + gpio_set(ENABLE_LEFT_DISPLAY); + printf("enabling right display\n"); + gpio_set(ENABLE_RIGHT_DISPLAY); + + + printf("mapping framebuffer...\n"); + struct fb_var_screeninfo si = { 0 }; + + int fbfd = open("/dev/fb0", O_RDWR); + + struct fb_fix_screeninfo fsi; + int io = ioctl(fbfd, FBIOGET_FSCREENINFO, &fsi); + dumpfsi("FBIOGET_FSCREENINFO", io, &fsi); + + io = ioctl(fbfd, FBIOGET_VSCREENINFO, &si); + dumpsi("FBIOEGET_VSCREENINFO", io, &si); + + si.bits_per_pixel = 8; + si.grayscale = 1; + si.activate = FB_ACTIVATE_FORCE; + + io = ioctl(fbfd, FBIOPUT_VSCREENINFO, &si); + dumpsi("FBIOPUT_VSCREENINFO", io, &si); + + fbaddr = mmap(NULL, fsi.smem_len, PROT_READ | PROT_WRITE, MAP_PRIVATE, fbfd, 0); + + for (unsigned int i = 0; i < fsi.smem_len; i++) { + fbaddr[i] = i % 2 == 0 ? '\0' : '\xff'; + } + + close(fbfd); + printf("at %p\n", fbaddr); +} |