From mboxrd@z Thu Jan 1 00:00:00 1970
From: peter@hurleysoftware.com (Peter Hurley)
Date: Wed, 17 Sep 2014 08:20:41 -0400
Subject: [PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround
for AM33xx
In-Reply-To: <54186B89.8050505@linutronix.de>
References: <1410377411-26656-1-git-send-email-bigeasy@linutronix.de>
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<20140911111721.GB17476@xps8300> <54118AAB.2010205@linutronix.de>
<5411967A.6090406@hurleysoftware.com> <54119AAA.9080907@linutronix.de>
<5411B33F.10405@hurleysoftware.com> <54171B85.5060209@linutronix.de>
<54186B89.8050505@linutronix.de>
Message-ID: <54197C99.8030601@hurleysoftware.com>
To: linux-arm-kernel@lists.infradead.org
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On 09/16/2014 12:55 PM, Sebastian Andrzej Siewior wrote:
> On 09/15/2014 07:01 PM, Sebastian Andrzej Siewior wrote:
>> On 09/11/2014 04:35 PM, Peter Hurley wrote:
>>> I do need to find out if omap hardware sets UART_MSR_DCTS when auto CTS
>>> is on. Would you mind running the debug patch below with HW flow control on?
>>
>> I didn't forget about this. However I told minicom to use hardware flow
>> control (and I see the driver set the HW bit) but I haven't seen that
>> uart_handle_cts_change() has been invoked at all. I'm going to check
>> two other boards and report then.
>
> No, I don't get into this at all function.
Ok, good to know. Thanks for testing that.
> So I connected my am335x-evm
> with beagle board xm because both of them have an old fashion UART
> connector (instead those uart-to-usb). Both configured with HW-Flow and
> I haven't seen the function invoked but I saw "port->icount.overrun"
> being incremented. This shouldn't happen. So I am a little puzzled here?
Yeah, that's weird. Do you have a break-out box to confirm that RTS/CTS are
being driven?
Regards,
Peter Hurley