From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755028AbaI2QPM (ORCPT ); Mon, 29 Sep 2014 12:15:12 -0400 Received: from www.linutronix.de ([62.245.132.108]:52824 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754015AbaI2QPI convert rfc822-to-8bit (ORCPT ); Mon, 29 Sep 2014 12:15:08 -0400 Date: Mon, 29 Sep 2014 18:15:05 +0200 From: Sebastian Andrzej Siewior To: Peter Hurley 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 Message-ID: <20140929161505.GF13142@linutronix.de> 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> <54197C99.8030601@hurleysoftware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <54197C99.8030601@hurleysoftware.com> X-Key-Id: 97C4700B X-Key-Fingerprint: 09E2 D1F3 9A3A FF13 C3D3 961C 0688 1C1E 97C4 700B User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Peter Hurley | 2014-09-17 08:20:41 [-0400]: >> 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 hereā€¦ > >Yeah, that's weird. Do you have a break-out box to confirm that RTS/CTS are >being driven? => - beagle board According to schematics the board has only RX and TX connected. No RTS/CTS - am335x-evm The schematics say "DNI" next to a resistor on RTS/CTS. DNI stands most likely for "Do Not Install". With a scope it looks like the the wire behind the MAX is open. - beagle bone black Only RX and TX are wired towards the USB2serial device. In short: each device I have has RTS/CTS not working/connected and I can't test HW handshake with HW available. >Regards, >Peter Hurley Sebastian From mboxrd@z Thu Jan 1 00:00:00 1970 From: bigeasy@linutronix.de (Sebastian Andrzej Siewior) Date: Mon, 29 Sep 2014 18:15:05 +0200 Subject: [PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround for AM33xx In-Reply-To: <54197C99.8030601@hurleysoftware.com> 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> <54197C99.8030601@hurleysoftware.com> Message-ID: <20140929161505.GF13142@linutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org * Peter Hurley | 2014-09-17 08:20:41 [-0400]: >> 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? => - beagle board According to schematics the board has only RX and TX connected. No RTS/CTS - am335x-evm The schematics say "DNI" next to a resistor on RTS/CTS. DNI stands most likely for "Do Not Install". With a scope it looks like the the wire behind the MAX is open. - beagle bone black Only RX and TX are wired towards the USB2serial device. In short: each device I have has RTS/CTS not working/connected and I can't test HW handshake with HW available. >Regards, >Peter Hurley Sebastian