From patchwork Thu Jan 5 09:31:21 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shawn Lin X-Patchwork-Id: 9498783 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 87D5760235 for ; Thu, 5 Jan 2017 09:33:22 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6C6102815E for ; Thu, 5 Jan 2017 09:33:22 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5E48C28179; Thu, 5 Jan 2017 09:33:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RCVD_IN_SORBS_SPAM,URIBL_BLACK autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id F1E252815E for ; Thu, 5 Jan 2017 09:33:21 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1cP4Q7-0001fR-Bx; Thu, 05 Jan 2017 09:33:15 +0000 Received: from lucky1.263xmail.com ([211.157.147.134]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cP4Q3-0001Rm-KL for linux-rockchip@lists.infradead.org; Thu, 05 Jan 2017 09:33:13 +0000 Received: from shawn.lin?rock-chips.com (unknown [192.168.167.11]) by lucky1.263xmail.com (Postfix) with ESMTP id A38951040; Thu, 5 Jan 2017 17:32:44 +0800 (CST) X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 Received: from localhost.localdomain (localhost [127.0.0.1]) by smtp.263.net (Postfix) with ESMTP id D4A28417; Thu, 5 Jan 2017 17:32:43 +0800 (CST) X-RL-SENDER: shawn.lin@rock-chips.com X-FST-TO: kishon@ti.com X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: shawn.lin@rock-chips.com X-UNIQUE-TAG: X-ATTACHMENT-NUM: 0 X-SENDER: lintao@rock-chips.com X-DNS-TYPE: 0 Received: from localhost.localdomain (unknown [58.22.7.114]) by smtp.263.net (Postfix) whith ESMTP id 16642WID1SX; Thu, 05 Jan 2017 17:32:44 +0800 (CST) From: Shawn Lin To: Kishon Vijay Abraham I Subject: [PATCH 1/2] Documentation: phy: introduce new optional property to specify drive impedance Date: Thu, 5 Jan 2017 17:31:21 +0800 Message-Id: <1483608682-226716-1-git-send-email-shawn.lin@rock-chips.com> X-Mailer: git-send-email 1.9.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170105_013311_878558_389DAA2F X-CRM114-Status: UNSURE ( 4.73 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Heiko Stuebner , Shawn Lin , Douglas Anderson , linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org, Rob Herring MIME-Version: 1.0 Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+patchwork-linux-rockchip=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP We need to modify the drive impedance according to the different hardware condition. So let's expose this to the DT. Signed-off-by: Shawn Lin --- Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt index e3ea557..731aeb9 100644 --- a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt +++ b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt @@ -14,6 +14,11 @@ specified by name: access to it), it is strongly suggested. - clocks: Should have a phandle to the card clock exported by the SDHCI driver. +Optional Properties: +- drive_impedance: Must be one of 33, 40, 50, 66, 100. This property allows + different boards to specify their own drive impedance depending on the + hardware condition. + Example: