From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755470AbaIQMUz (ORCPT ); Wed, 17 Sep 2014 08:20:55 -0400 Received: from mailout32.mail01.mtsvc.net ([216.70.64.70]:45802 "EHLO n23.mail01.mtsvc.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754904AbaIQMUx (ORCPT ); Wed, 17 Sep 2014 08:20:53 -0400 Message-ID: <54197C99.8030601@hurleysoftware.com> Date: Wed, 17 Sep 2014 08:20:41 -0400 From: Peter Hurley User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.1.1 MIME-Version: 1.0 To: Sebastian Andrzej Siewior CC: Heikki Krogerus , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, tony@atomide.com, balbi@ti.com, gregkh@linuxfoundation.org, Alan Cox Subject: Re: [PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround for AM33xx References: <1410377411-26656-1-git-send-email-bigeasy@linutronix.de> <1410377411-26656-10-git-send-email-bigeasy@linutronix.de> <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> In-Reply-To: <54186B89.8050505@linutronix.de> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Authenticated-User: 990527 peter@hurleysoftware.com X-MT-ID: 8FA290C2A27252AACF65DBC4A42F3CE3735FB2A4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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