Hi Greg! On Wed, Dec 01, 2010 at 02:16:04PM -0800, Greg KH wrote: > On Wed, Dec 01, 2010 at 05:46:34PM +0100, Matthias Reichl wrote: > > I've got a Lindy 51237 multi I/O card (2 16C950 URATs up to 921kbit > > plus one parallel port) with a Oxford OXuPCI952 chip (PCI vendor > > ID 0x1415, device ID 0x9505). > > > > http://www.lindy-international.com/2-port-rs-232-serial-1-port-parallel-card-pci/51237.html > > http://www.plxtech.com/products/uart/oxupci952 > > > > Kernel 2.6.36.1 doesn't contain any device-specific configuration, > > the "guess code" detects both UARTs at BAR0 and BAR1, > > but with the wrong baudrate (default of 115200 instead of > > 921600 needed for this card). > > > > The card doesn't report any specific (sub-) vendor/device IDs but > > the generic Oxford IDs. So adding an entry to the pci_device_id > > table with a pbn_b0_bt_2_921600 config might break some prior > > working setups (OXuPCI952 with baud_base=115200). > > > > Do you have any policy how to cope with such situations? > > Always set the baud rate to a valid one before using the tty port? Sorry, I meant baud_base (or base_baud in 8250_pci.c), not baudrate :-( Since the baud_base is differing (115200 instead of 921600) setting a baudrate of X results in an actual baudrate of X*8 for this card. It's no problem for me to do a "setserial ... baud_base=921600" or pass a module/kernel parameter to circumvent the problem, but it sure would be nicer if the kernel would have set the baud_base correctly. The problem I'm seeing here is that this card is using a stock OXuPCI952, which can be equipped with any oscillator, and doesn't report any vendor-specific PCI IDs that lets it be distinguished from other stock OXuPCI952 cards - otherwise I've just sent a "[PATCH] Add support for Lindy 51237" to set baud_base=921600 for this specific card. Personally, all 16C950 (compatible) cards I've bought so far were capable of a max. 921kbit/sec (and thus had a baud_base of 921600). So the current default of 115200 doesn't quite match my setup. If I only need a card capable of 115200 bit/sec I usually buy a standard 16550 card (not a 16C950). So, my question is: would you include a patch in the kernel to change the default baud_base from 115200 to 921600 for the OXuPCI952 chip (1415:9505)? so long, Hias -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
