Show loaded Drivers

toredo · 05-06-2010, 03:47 AM

Hello,

I have a device /dev/ttyS4 and i wanna know which driver it uses.

The problem is:
If i compile a new kernel with the same configuration-file the device /dev/ttyS4 is away.

So i wanna know which driver it uses.

Can someone help me?

regards
toredo

deadeyes · 05-06-2010, 08:17 AM

What you can do is do a long listing of the file and look at the major and minor device number.
Then you can create these manually and see if that works.
ls -l /dev/ttyS0
crw-rw---- 1 root uucp 4, 64 May 6 2010 /dev/ttyS0
So a character device using major device 4 and minor device number 64 IIRC.
With mknod you can make a new device file.

I think the functionality is something like RS232 in the kernel config but I am not sure at all, this has been a long time since I used it.

Shadow_7 · 05-06-2010, 09:25 AM

*tty*'s are probably in inittab.

$ cat /etc/inittab

You can view them in ps with their launching syntax.

$ ps wafu

getty is a normal driver, but there are other tty handlers.

$ find /sbin/ -iname '*tty*'
$ dpkg -l '*tty*'

Shadow_7 · 05-06-2010, 09:29 AM

There's a few win-modems that create /dev/tty??#'s as well.

wvdial might help tell you what you've got. although it only works if you have said drivers to test against.

martian something for my lucent modems. A few linuxant things for conexant modems and other things. Not that common with broadband and standard DHCP or WiFi devices these days.

toredo · 05-07-2010, 01:08 AM

thx for the answers.

i have found it, i didn't patch the kernelen:

Quote:

...
+ /* USART1 on ttyS4. (Rx, Tx only) */
+ at91_register_uart(AT91SAM9260_ID_US4, 4, 0);
...

regards
toredo