The (gnu) stty program is part of the official repository:
root@jwd2:~# opkg list | grep stty coreutils-stty - 8.16-1 - Full version of standard GNU stty utility. Normally, you would not use this package, since the functionality in BusyBox is more than sufficient.
The comment is a bit misleading because the BusyBox implementation doesn’t have an stty functionality (as far as I know); also, on boot time the uart is set to 250000 baud;
dmesg | grep ttyATH0 [ 0.000000] Kernel command line: board=Yun console=ttyATH0,250000 mtdparts=spi0.0:256k(u-boot)ro,64k(u-boot-env)ro,14656k(rootfs),1280k(kernel),64k(nvram),64k(art),15936k@0x50000(firmware) rootfstype=squashfs,jffs2 noinitrd
Now run ‘stty -F /dev/ttyATH0’; gnu stty reports a baudrate of 230400; even if you explicitly try to set it to 250000 baud (which is was already set to).
It isn’t much of a problem because I want to run that serial bus as fast as possible (250000BD?) but it this a limitation of the gnu implementation of stty?