From patchwork Wed Jan 25 20:28:09 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Brandt X-Patchwork-Id: 9537913 X-Patchwork-Delegate: geert@linux-m68k.org 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 9D76E6046A for ; Wed, 25 Jan 2017 20:28:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8F80827F9F for ; Wed, 25 Jan 2017 20:28:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8425F27FBC; Wed, 25 Jan 2017 20:28:54 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DD69028047 for ; Wed, 25 Jan 2017 20:28:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752581AbdAYU2v (ORCPT ); Wed, 25 Jan 2017 15:28:51 -0500 Received: from relmlor3.renesas.com ([210.160.252.173]:50413 "EHLO relmlie2.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752446AbdAYU2p (ORCPT ); Wed, 25 Jan 2017 15:28:45 -0500 Received: from unknown (HELO relmlir4.idc.renesas.com) ([10.200.68.154]) by relmlie2.idc.renesas.com with ESMTP; 26 Jan 2017 05:28:38 +0900 Received: from relmlac3.idc.renesas.com (relmlac3.idc.renesas.com [10.200.69.23]) by relmlir4.idc.renesas.com (Postfix) with ESMTP id 36EE140445; Thu, 26 Jan 2017 05:28:38 +0900 (JST) Received: by relmlac3.idc.renesas.com (Postfix, from userid 0) id 1D31218070; Thu, 26 Jan 2017 05:28:38 +0900 (JST) Received: from relmlac3.idc.renesas.com (localhost [127.0.0.1]) by relmlac3.idc.renesas.com (Postfix) with ESMTP id 15CA31806F; Thu, 26 Jan 2017 05:28:38 +0900 (JST) Received: from relmlii1.idc.renesas.com [10.200.68.65] by relmlac3.idc.renesas.com with ESMTP id FAH20516; Thu, 26 Jan 2017 05:28:38 +0900 X-IronPort-AV: E=Sophos;i="5.33,285,1477926000"; d="scan'208";a="231842111" Received: from unknown (HELO rtamta01.rta.renesas.com) ([143.103.48.75]) by relmlii1.idc.renesas.com with ESMTP; 26 Jan 2017 05:28:36 +0900 Received: from localhost.localdomain (unknown [172.27.49.212]) by rtamta01.rta.renesas.com (Postfix) with ESMTP id 52EA63DB; Wed, 25 Jan 2017 20:28:31 +0000 (UTC) From: Chris Brandt To: Ulf Hansson , Rob Herring , Mark Rutland , Simon Horman , Wolfram Sang , Geert Uytterhoeven Cc: devicetree@vger.kernel.org, linux-mmc@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Chris Brandt Subject: [PATCH v6 2/3] mmc: sh_mobile_sdhi: explain clock bindings Date: Wed, 25 Jan 2017 15:28:09 -0500 Message-Id: <20170125202810.16876-3-chris.brandt@renesas.com> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20170125202810.16876-1-chris.brandt@renesas.com> References: <20170125202810.16876-1-chris.brandt@renesas.com> Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In the case of a single clock source, you don't need names. However, if the controller has 2 clock sources, you need to name them correctly so the driver can find the 2nd one. The 2nd clock is for the internal card detect logic. Signed-off-by: Chris Brandt Reviewed-by: Geert Uytterhoeven Acked-by: Rob Herring --- v5: * add Reviewed-by: Geert Uytterhoeven * list number of clocks for each SoC * remove example because it already exists in mmc.txt v4: * just explain there might be 2 clocks, don't explain how we will use them in the driver v3: * add more clarification about why there are sometimes 2 clocks and what you should do with them. * remove 'status = "disabled"' from example v2: * fix spelling and change wording * changed clock name from "carddetect" to "cd" --- Documentation/devicetree/bindings/mmc/tmio_mmc.txt | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt index a1650ed..4fd8b7a 100644 --- a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt +++ b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt @@ -25,6 +25,19 @@ Required properties: "renesas,sdhi-r8a7795" - SDHI IP on R8A7795 SoC "renesas,sdhi-r8a7796" - SDHI IP on R8A7796 SoC +- clocks: Most controllers only have 1 clock source per channel. However, on + some variations of this controller, the internal card detection + logic that exists in this controller is sectioned off to be run by a + separate second clock source to allow the main core clock to be turned + off to save power. + If 2 clocks are specified by the hardware, you must name them as + "core" and "cd". If the controller only has 1 clock, naming is not + required. + Below is the number clocks for each supported SoC: + 1: SH73A0, R8A73A4, R8A7740, R8A7778, R8A7779, R8A7790 + R8A7791, R8A7792, R8A7793, R8A7794, R8A7795, R8A7796 + 2: R7S72100 + Optional properties: - toshiba,mmc-wrprotect-disable: write-protect detection is unavailable - pinctrl-names: should be "default", "state_uhs"