From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5C3C3C46CD2 for ; Tue, 30 Jan 2024 12:30:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:In-Reply-To:References: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=liTYVqRCswZ6iZfR+tlQmkZJx4T4RrGlUk/r0JDvncQ=; b=dyE2kx61ORx1qA cSUijutqv0yprUmk/P6CSOjYcK/ctht58FjbMhvCV2AMUdSC25AegRDwjVhK70UEUaZGYyFHpnCHM yKjYzKCh6lowLwYP/SLIS7rPfShlNs0K37iwdAf9G5GdVg1bllPKDFmu749QqyeabXDAKZclI6k+U LR0k1nrd+JRr7HTbm5UF7NMaXgBuZJ7zchfLMP1ILufI2eA4AT1femb81Rzft++RQmbXYmeK0SrjI e3xPDqsKH4qA4sOjNG5VVYsijrxGw4ubV+Bpnd60WLNJ2J1TqbODR3+YKv9Y0bdyHMiEintEoA4ag EDjOTQjwwnnn1TcJKSCA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rUnGD-0000000Gfev-08iq; Tue, 30 Jan 2024 12:30:41 +0000 Received: from mx2.securetransport.de ([2a03:4000:13:6c7::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rUnG8-0000000Gfe9-3A2S; Tue, 30 Jan 2024 12:30:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dh-electronics.com; s=dhelectronicscom; t=1706617791; bh=LWCEE7Ky7ZqC2xZnLL48J6mdU/wI6QANLum+jdUp8h0=; h=From:To:CC:Subject:Date:References:In-Reply-To:From; b=NgId3XpE+F7hU3JeeLXAjPrhKu+VadeUAbULAkoAsMkzesjEieSKAiGsfiyrPNtA+ qw+d1amDXOCQd5vbru+vg78kXzeNnsGlYQPP6qvSwJRYcgj50+xQlIR6q1jqxaV5Zk SLrv9M0tovDUYBwzTGhkOsceeFUxwzFE1NNE59qcbLxdvqg92rGdJpFPTw9BDvdVaZ ahJkQfTRibb211YJNJQo0vDS56xkNAx04VcAkFhCp1fwxSaSShTX8RM3ZVIsGsl8zv BAF0CiYnEJr2jSuF2Ehn+1sW4AXxy/tVSK0bwDI7TemAp6QAVnFZzOG7VZO7C2kUvV YJeC2zlJhtMAg== X-secureTransport-forwarded: yes From: Christoph Niedermaier Complaints-To: abuse@cubewerk.de To: Farouk Bouabid , Lino Sanfilippo , Greg Kroah-Hartman , Jiri Slaby , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiko Stuebner CC: Rob Herring , "linux-kernel@vger.kernel.org" , "linux-serial@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-rockchip@lists.infradead.org" , "quentin.schulz@theobroma-systems.com" , Heiko Stuebner Subject: RE: [PATCH v5 2/6] serial: 8250: Support separate rs485 rx-enable GPIO Thread-Topic: [PATCH v5 2/6] serial: 8250: Support separate rs485 rx-enable GPIO Thread-Index: AQHaUH1C9lFNHAGCbEecDp85JK6VnLDscmeAgAP+JYCAAd4lkA== Date: Tue, 30 Jan 2024 12:29:47 +0000 Message-ID: <3d31b17ffd4a4f02aaaa1b6c33a09009@dh-electronics.com> References: <20240126-dev-rx-enable-v5-0-5d934eda05ca@theobroma-systems.com> <20240126-dev-rx-enable-v5-2-5d934eda05ca@theobroma-systems.com> <098216ce-50b3-43e4-ad1a-42228c58b761@gmx.de> <37522087-d3ac-4cc7-b11b-c844d36206ba@theobroma-systems.com> In-Reply-To: <37522087-d3ac-4cc7-b11b-c844d36206ba@theobroma-systems.com> Accept-Language: de-DE, en-US Content-Language: de-DE X-MS-Has-Attach: X-MS-TNEF-Correlator: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240130_043037_050070_68804395 X-CRM114-Status: GOOD ( 13.32 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org From: Farouk Bouabid Sent: Monday, January 29, 2024 9:57 AM Hi, > On 26.01.24 20:58, Lino Sanfilippo wrote: >> [Some people who received this message don't often get email from linosanfilippo@gmx.de. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] >> >> Hi, >> >> On 26.01.24 18:27, Farouk Bouabid wrote: >>> From: Heiko Stuebner >>> >>> The RE signal is used to control the duplex mode of transmissions, >>> aka receiving data while sending in full duplex mode, while stopping >>> receiving data in half-duplex mode. >>> >>> On a number of boards the !RE signal is tied to ground so reception >>> is always enabled except if the UART allows disabling the receiver. >>> This can be taken advantage of to implement half-duplex mode - like >>> done on 8250_bcm2835aux. >>> >>> Another solution is to tie !RE to RTS always forcing half-duplex mode. >>> >>> And finally there is the option to control the RE signal separately, >>> like done here by introducing a new rs485-specific gpio that can be >>> set depending on the RX_DURING_TX setting in the common em485 callbacks. >>> >> we just added the rx_during_tx_gpio to the serial core. >> Why cant you use this GPIO for your purpose? >> >> Regards, >> Lino. > What we are trying to implement is a gpio that emulates the RTS signal > itself as we do not have a dedicated RTS signal that can be controlled > through MCR. The rx during tx state in our case is a fixed state of > "NO_RX_WHILE_TX" Why can't the property rts-gpios be used here for this purpose? Regards Christoph _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip