Re: [PATCH v3 4/6] ARM: dts: imx6q{dl}: fix the wrong RTS/CTS pad name

[Huang Shijie <b32955@freescale.com>]

于 2013年07月08日 15:50, Russell King - ARM Linux 写道:
> On Sun, Jul 07, 2013 at 01:51:14PM +0200, Lothar Waßmann wrote:
>> Hi,
>>
>> Shawn Guo writes:
>>> On Fri, Jul 05, 2013 at 02:12:30PM +0800, Huang Shijie wrote:
>>>> There is something wrong with the RTS/CTS pads:
>>>>    The RTS pad is assigned with the CTS's value;
>>>>    while the CTS pad is assigned with the RTS's value.
>>>>
>>> So basically, you are saying that select_input should be set up for CTS
>>> rather than RTS.  It seems that the people who generated the macro got
>>> the wrong input from developer.
>>>
>> programming 'select_input' only makes sense for inputs, not outputs.
>> Since CTS is an output signal, select_input only makes sense for the
>> RTS function of the pads.
> Note: If you are a DTE, then RTS is an output, CTS is an input.  If you
> are a DCE, then RTS is an input and CTS is an output (normally on a
> standard UART, you just swap the wiring for RTS and CTS but really that's
> all that is going on.)  So swapping them in software should be acceptable
> too, provided you're not having to disable any auto flow control facilities.
>
thanks for explanation.


Huang Shijie

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