Re: fbcon gives mirrored fonts on monochrome display

Hi Noralf,

On Thu, Jan 22, 2015 at 8:55 PM, Noralf Trønnes [off-list ref] wrote:

Den 22.01.2015 20:44, skrev Geert Uytterhoeven:

quoted

On Thu, Jan 22, 2015 at 7:47 PM, Noralf Trønnes [off-list ref] wrote:

quoted

I'm playing with a SSD1306 128x64 monochrome display and fbcon gives me
mirrored fonts and some extra lines.
fbdev config:
   info->var.bits_per_pixel = 1;
   info->fix.visual = FB_VISUAL_MONO10;
   info->var.red.length = 1;
   info->var.red.offset = 0;
   info->var.green.length = 1;
   info->var.green.offset = 0;
   info->var.blue.length = 1;
   info->var.blue.offset = 0;
Uses: sys_fillrect, sys_copyarea, sys_imageblit (and deferred_io)

System: Raspberry Pi, ARM, Linux 3.18.3

Does anyone see what this might be?

What's the value on CONFIG_FB_CFB_REV_PIXELS_IN_BYTE in your .config?

$ zgrep CONFIG_FB_CFB_REV_PIXELS_IN_BYTE /proc/config.gz
# CONFIG_FB_CFB_REV_PIXELS_IN_BYTE is not set

quoted

Does your driver set FB_NONSTD_REV_PIX_IN_B?

No it doesn't. I also tried setting it now, with no effect:
info->var.nonstd = FB_NONSTD_REV_PIX_IN_B;

The latter only seems to matter if CONFIG_FB_CFB_REV_PIXELS_IN_BYTE
is set, so please try the config option first.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.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