From mboxrd@z Thu Jan 1 00:00:00 1970 From: Huang Shijie Subject: Re: [PATCH v3 4/6] ARM: dts: imx6q{dl}: fix the wrong RTS/CTS pad name Date: Mon, 8 Jul 2013 16:54:36 +0800 Message-ID: <51DA7E4C.4050507@freescale.com> References: <1373004752-21302-1-git-send-email-b32955@freescale.com> <1373004752-21302-5-git-send-email-b32955@freescale.com> <20130706050803.GC30164@S2101-09.ap.freescale.net> <20953.22066.706534.773272@ipc1.ka-ro> <20130708075004.GR24642@n2100.arm.linux Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from tx2ehsobe005.messaging.microsoft.com ([65.55.88.15]:28843 "EHLO tx2outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751719Ab3GHIup convert rfc822-to-8bit (ORCPT ); Mon, 8 Jul 2013 04:50:45 -0400 In-Reply-To: <20130708075004.GR24642@n2100.arm.linux.org.uk> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Russell King - ARM Linux Cc: =?UTF-8?B?TG90aGFyIFdhw59tYW5u?= , Shawn Guo , linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, gregkh@linuxfoundation.org =E4=BA=8E 2013=E5=B9=B407=E6=9C=8808=E6=97=A5 15:50, Russell King - ARM= Linux =E5=86=99=E9=81=93: > On Sun, Jul 07, 2013 at 01:51:14PM +0200, Lothar Wa=C3=9Fmann 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 y= ou > 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 th= at's > all that is going on.) So swapping them in software should be accept= able > too, provided you're not having to disable any auto flow control faci= lities. > thanks for explanation. Huang Shijie -- To unsubscribe from this list: send the line "unsubscribe linux-serial"= in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: b32955@freescale.com (Huang Shijie) Date: Mon, 8 Jul 2013 16:54:36 +0800 Subject: [PATCH v3 4/6] ARM: dts: imx6q{dl}: fix the wrong RTS/CTS pad name In-Reply-To: <20130708075004.GR24642@n2100.arm.linux.org.uk> References: <1373004752-21302-1-git-send-email-b32955@freescale.com> <1373004752-21302-5-git-send-email-b32955@freescale.com> <20130706050803.GC30164@S2101-09.ap.freescale.net> <20953.22066.706534.773272@ipc1.ka-ro> <20130708075004.GR24642@n2100.arm.linux Message-ID: <51DA7E4C.4050507@freescale.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org ? 2013?07?08? 15:50, Russell King - ARM Linux ??: > On Sun, Jul 07, 2013 at 01:51:14PM +0200, Lothar Wa?mann 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