From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1906823-1518710898-5-4790253613351037441 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1518710898; b=FLVbCrnnyQweIMw0raEAL51lo+PA97Qf/j/n+POuwfKpbGU +ZZC2me27jSLIfpqEDntyaw4YotVUI9tdkxFj4esbWgrvZxYQu9rHD1f9H3O+Brn sii5132cv3yh07LLe9nz7fOtRIpL7J+LwDaByxypp3BM218ZHMqbJuVI2qI9Bykr 0BdhpeT+HBODRk9biofMavyOgvUt4MOudlRroxtuFT0NAiU403GgfUHlEv7gzuaw ltrsSwWFRG9wGCI12m5hZGAvbsV6bj/LC+VsllVqRmB0zWn/XWCeLBS404FPox39 89i2XwRybDEL/2L1SbiHUIQqr5oGdo+uaH4gKww== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1518710898; bh=7BXcOCWnrE7NBfxr3gIzV/irzk ypEqpaGcazBTq/4yU=; b=AlaTh+iWwKjLfs8XdK1n1ePhLmt0m1eEi5aGT7WeFd 5+ZW9f3dXFEzmA9tJORDadG3BQDlxIWy1IMrkRw6Qya3DAR/fdTVMplKl3q8OWTG dDyAgUga/uH36V+nTWBdamz5UnvbZ6mnYPgxy7NtHaGBVvN8iHHHE/yqh80+RIM/ nnMyyfQiGaetV2dM321NNNf2nkIUrJr9YRT9ScXeXDyegDtQooW/JdUjfDRDLKA2 SC7N/185qu0TdQ2C3IWqzrfQqmixaUrVhYXSAhA29TmXMqVdjXyNFgn+OKMmTGBT CLVLe37ZbFN4L88ad1QOQIYulWiXuEUzflQP/lr2OVjw== ARC-Authentication-Results: i=1; mx5.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx5.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033898AbeBOQIO (ORCPT ); Thu, 15 Feb 2018 11:08:14 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:35010 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1424492AbeBOPpe (ORCPT ); Thu, 15 Feb 2018 10:45:34 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hans Verkuil , Rob Herring , Mauro Carvalho Chehab Subject: [PATCH 4.15 152/202] media: dt-bindings/media/cec-gpio.txt: mention the CEC/HPD max voltages Date: Thu, 15 Feb 2018 16:17:32 +0100 Message-Id: <20180215151720.914665776@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180215151712.768794354@linuxfoundation.org> References: <20180215151712.768794354@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hans Verkuil commit dac15ed62dc9d7898d3695a3c393d6f712d66185 upstream. Mention the maximum voltages of the CEC and HPD lines. Since in the example these lines are connected to a Raspberry Pi and the Rpi GPIO lines are 3.3V it is a good idea to warn against directly connecting the HPD to the Raspberry Pi's GPIO line. Signed-off-by: Hans Verkuil Reviewed-by: Rob Herring Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- Documentation/devicetree/bindings/media/cec-gpio.txt | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/Documentation/devicetree/bindings/media/cec-gpio.txt +++ b/Documentation/devicetree/bindings/media/cec-gpio.txt @@ -4,6 +4,10 @@ The HDMI CEC GPIO module supports CEC im is hooked up to a pull-up GPIO line and - optionally - the HPD line is hooked up to another GPIO line. +Please note: the maximum voltage for the CEC line is 3.63V, for the HPD +line it is 5.3V. So you may need some sort of level conversion circuitry +when connecting them to a GPIO line. + Required properties: - compatible: value must be "cec-gpio". - cec-gpios: gpio that the CEC line is connected to. The line should be @@ -21,7 +25,7 @@ the following property is optional: Example for the Raspberry Pi 3 where the CEC line is connected to pin 26 aka BCM7 aka CE1 on the GPIO pin header and the HPD line is -connected to pin 11 aka BCM17: +connected to pin 11 aka BCM17 (some level shifter is needed for this!): #include