framebuffer driver

Sudip Mukherjee sudipm.mukherjee at gmail.com
Sat Dec 13 05:24:42 EST 2014


another update.
For testing I disabled my on-board graphics. so when system is booting
up, it is not having any /dev/fb0 . I am now connecting to it through
ssh and loading the module. after module is inserted the board is
initialized and I got my /dev/fb0, I have also attached the dmesg. But
the monitor is still blank. :(

any hints please ...

thanks
sudip



On Fri, Dec 12, 2014 at 4:13 PM, Sudip Mukherjee
<sudipm.mukherjee at gmail.com> wrote:
> an update .. I am getting the debug messages from ioctl ... by mistake
> I placed the debugging messages in FBIOGET_CON2FBMAP.
> so if ioctl is executing, on pressing alt+ctrl+F2 the console should
> display on the second monitor (if i am wrong), but nothing is showing
> on that.
>
> sudip
>
>
> On Fri, Dec 12, 2014 at 1:38 PM, Sudip Mukherjee
> <sudipm.mukherjee at gmail.com> wrote:
>> Hi,
>> I have started with a pci based vga card. after booting i can see the
>> card in lspci , and after loading the driver as a module i can see
>> that the driver is linked with the device using lspci -k.
>>
>> for initial testing, i am using the ioctl command FBIOPUT_CON2FBMAP ,
>> which is supposed to map a console to a particular framebuffer. But on
>> switching to that console I am not getting anything in the monitor. To
>> test if ioctl is getting executed, i inserted some debugging messages
>> as pr_err() in that particular case of the ioctl function in
>> drivers/video/fbdev/core/fbmem.c , but after calling the ioctl again i
>> am not getting those debug messages in dmesg.
>> Now i am in doubt about what is happening.. if ioctl is executed then
>> my debug messages should have been printed.
>>
>> Can anyone please give me some hints about how to test this new vga
>> card... and also why the debug messages from ioctl is not getting
>> printed ..
>>
>> i think its almost a similar thing as https://lkml.org/lkml/2009/12/2/288
>>
>>
>> thanks
>> sudip



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