On Mon, May 28, 2012 at 07:48:57PM +0200, Roland Stigge wrote: > On 28/05/12 18:31, Russell King - ARM Linux wrote: > >>>> So maybe 16750 is the better choice for me, anyway. Already supported in > >>>> of-serial. Works for now, but need more testing. Another hint is that > >>>> 16750 is advertised as "IP core for Soc" which matches the case of LPC32xx. > >>> > >>> 16750 also has automatic hardware flow control support, selectable through > >>> bit 5 in the MCR register. If your UART has that, then it's probably a > >>> 16750 derivative rather than a 16550 or 16650 derivative. > >>> > >>> 16650s have an EFR register at offset 2, selectable by writing 0xBF into > >>> the LCR register, which the 16750 doesn't have. 16650 also has automatic > >>> hardware flow control, bit this is selected through a couple of bits in > >>> the EFR. > >> > >> The 4 LPC32xx's "Standard" UARTs have neither of those. > >> > >> Is it ok to use "ns16650", i.e. PORT_16650, or do I need to introduce a > >> FIFO depth configuration? > > > > I think you need a new type, because as I said above, 16650s have that > > additional EFR, and we will attempt to access that register which > > isn't present in yours. > > I actually meant 16750 instead of 16650, sorry, but this basically means > the same - I would refer to extensions that are actually not there... > > Now, introducing a new type, can I add to 8250.c's uart_config[] by > introducing a new type (no. 22) after PORT_XR17D15X? Unfortunately, > there are the "ARM specific type numbers" after current PORT_MAX_8250 > (21), but those are not listed in 8250.c's uart_config[]. Or how am I > supposed to add a new type? If it's 8250, stick it in with the group, otherwise the array will become stupidly large. That's why there's a separation of the two. -- 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
