Question about serial console code

Marcel Moolenaar xcllnt at mac.com
Mon Jun 18 15:40:16 UTC 2007


On Jun 17, 2007, at 11:59 PM, Christian Kandeler wrote:

>> If the UART has no FIFO (in the 16550-sense), then sc_txfifosz
>> is still 1.
>
> But where is this set? The ns8250_bus_probe() function returns  
> early when it
> detects a FIFO-less device, leaving sc_txfifosz at its pre- 
> initialized value
> (i.e. zero). And it doesn't seem to get set anywhere else, either.

Uhm, on line 817 in uart_dev_ns8250.c, which falls in function
uart_bus_probe(), both the rx and tx fifo sizes are set to 1.
This is for the case there's no fifo.
FYI,

-- 
Marcel Moolenaar
xcllnt at mac.com




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