Hi Dong, On Fri, Jan 27, 2017 at 6:38 AM, DongCV <cv-dong@xxxxxxxxxxx> wrote: > I've tested the linux v4.10-rc2 for Gen2 Lager and found two issues about > DISPLAY-UNIT: Does not support 640x480 resolution & Does not support 16-bit > for color numbers. > > "root@linaro-naro:~# fbset -xres 640 -yres 480 -laced 0 > ioctl FBIOPUT_VSCREENINFO: Invalid argument" > > "root@linaro-naro:~# fbset -depth 16 -rgba 5,6,5,0 > ioctl FBIOPUT_VSCREENINFO: Invalid argument" > > > And I found the patch which I think it is the cause of this issues. > The commit name is '865afb1 drm/fb-helper: reject any changes to the fbdev' > If I reverted this patch and retested it on H2 board, the issue will be > gone! > > Please have a look at the attached testlog file for detail. Do you get the correct output on the display after reverting that patch? Cfr. Laurent Pinchart's answer in the thread "Re: The failure summary report of GEN2 for linux stable v4.10-rc2": | I confirm your analysis. However, I think this isn't a new issue. Before | the aforementioned patch, running | | # fbset -xres 640 -yres 480 -laced 0 | # fbset -depth 16 -rgba 5,6,5,0 | | didn't produce any error, but didn't either resize the display to | 640x480 or changed the pixel format. With the patch applied, the | commands are rejected as they should be, as they wouldn't produce the | expected results. The new behaviour is thus in my opinion correct. http://www.mail-archive.com/linux-renesas-soc@xxxxxxxxxxxxxxx/msg10879.html Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx 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