On Tue, Oct 29, 2013 at 06:42:49PM +0100, Frank Schäfer wrote: > Am 29.10.2013 18:12, schrieb Frank Schäfer: > > Am 29.10.2013 10:07, schrieb Mika Westerberg: > >> On Mon, Oct 28, 2013 at 07:50:44PM +0100, Frank Schäfer wrote: > >>> Mika Westerberg has reported that the fixed+improved divisor based baud rate > >>> encoding method doesn't work anymore with his HXD device. > >>> So until we've found out what's going on, reintroduce the old encoding algorithm > >>> and use it for this and all newer chips for baud rates > 115200 baud. > >>> Also switch back to the direct encoding method for baud rates <= 115200, because > >>> it's unclear if the old divisor based encoding algorithm works for them. > >>> > >>> Reported-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> > >>> Signed-off-by: Frank Schäfer <fschaefer.oss@xxxxxxxxxxxxxx> > >> Tried this and with 115200 it works and fixes the problem. However, with > >> speeds like 230400 and 460800 it still corrupts data. > > Well, with this patch we go back to what we did since kernel 3.1 (since > > commit 8d48fdf689fe "USB: PL2303: correctly handle baudrates above > > 115200"), so you should face the same problems with these kernels, too. > I've double checked that. With this patch applied to 3.12-rc the baud > rate encoding is exactly the same as in 3.11 (for HXD chips). > > Are you sure your test setup is reliable / comparable ? Could you please > re-check your results ? I re-tested with 3.11 and 3.12-rc7 with this patch applied. With 3.11 all tried speeds (115200, 230400 and 460800) work fine. With 3.12-rc7 + this patch, 115200 works but 230400 and 460800 corrupt data. My test setup is such that I just start getty on ttyUSB0 with given speed and then connect to it using picocom. Once logged in, command like 'ls' will return listing that is corrupted somehow: [root@tbt02 /]# ls NH$�j�I[0m/ init* linuxrc@ opt/ run@ tmp/r/ etc/ lib/ media/ proc/ sbin/ usr/ It is supposed to look like: [root@tbt02 /]# ls bin/ home/ lib32@ mnt/ root/ sys/ var/ dev/ init* linuxrc@ opt/ run@ tmp/ etc/ lib/ media/ proc/ sbin/ usr/ -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
