Re: [PATCH v1 3/4] max3100: adds console support for MAX3100

[christian pellegrin]

On Mon, Mar 29, 2010 at 4:48 AM, Feng Tang <feng.tang@xxxxxxxxx> wrote:

>> +             tx |= MAX3100_WD | MAX3100_RTS;
>
> Does this imply to have to work with HW flow control? on my platform
> I have to remove the RTS bit to make it work.
>

Finally I had time to check this. If you compare the 8250 (or similar)
data-sheet with the MAX31x0 one you see that the handling of the
RTX/CTS bits is exactly the same (8250 about RTS bit for example:
"When any of these bits are cleared, the associated output is forced
high." and MAX3110: "Request-to-Send Bit. Controls the state of the
RTS output. This bit is reset on power-up (RTS
bit = 0 sets the RTS pin = logic high)."). If you look at the 8250.c
driver (grep for UART_MCR_RTS) you notice that the bit is set on
device open (together with DTR of course). So I think the driver is
doing the right thing here.

-- 
Christian Pellegrin, see http://www.evolware.org/chri/
"Real Programmers don't play tennis, or any other sport which requires
you to change clothes. Mountain climbing is OK, and Real Programmers
wear their climbing boots to work in case a mountain should suddenly
spring up in the middle of the computer room."
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