From patchwork Wed Jan 25 20:28:08 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Brandt X-Patchwork-Id: 9537909 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 2DB7C6046A 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 17E7D280CF for ; Wed, 25 Jan 2017 20:28:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 03349280B0; Wed, 25 Jan 2017 20:28:53 +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 4701727FB0 for ; Wed, 25 Jan 2017 20:28:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752325AbdAYU2q (ORCPT ); Wed, 25 Jan 2017 15:28:46 -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 S1752566AbdAYU2o (ORCPT ); Wed, 25 Jan 2017 15:28:44 -0500 Received: from unknown (HELO relmlir3.idc.renesas.com) ([10.200.68.153]) by relmlie2.idc.renesas.com with ESMTP; 26 Jan 2017 05:28:37 +0900 Received: from relmlac3.idc.renesas.com (relmlac3.idc.renesas.com [10.200.69.23]) by relmlir3.idc.renesas.com (Postfix) with ESMTP id 03DA741EFF; Thu, 26 Jan 2017 05:28:37 +0900 (JST) Received: by relmlac3.idc.renesas.com (Postfix, from userid 0) id EBE4818070; Thu, 26 Jan 2017 05:28:36 +0900 (JST) Received: from relmlac3.idc.renesas.com (localhost [127.0.0.1]) by relmlac3.idc.renesas.com (Postfix) with ESMTP id E6C481806F; Thu, 26 Jan 2017 05:28:36 +0900 (JST) Received: from relmlii1.idc.renesas.com [10.200.68.65] by relmlac3.idc.renesas.com with ESMTP id FAG20516; Thu, 26 Jan 2017 05:28:36 +0900 X-IronPort-AV: E=Sophos;i="5.33,285,1477926000"; d="scan'208";a="231842109" Received: from unknown (HELO rtamta01.rta.renesas.com) ([143.103.48.75]) by relmlii1.idc.renesas.com with ESMTP; 26 Jan 2017 05:28:35 +0900 Received: from localhost.localdomain (unknown [172.27.49.212]) by rtamta01.rta.renesas.com (Postfix) with ESMTP id 5029C3B9; Wed, 25 Jan 2017 20:28:30 +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 1/3] mmc: sh_mobile_sdhi: add support for 2 clocks Date: Wed, 25 Jan 2017 15:28:08 -0500 Message-Id: <20170125202810.16876-2-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 Some controllers have 2 clock sources instead of 1. The 2nd clock is for the internal card detect logic and must be enabled/disabled along with the main core clock for proper operation. Signed-off-by: Chris Brandt --- v5: * call clk_disable_unprepare even if clk_cd is NULL v4: * add technical explanation within probe routine v3: * add more clarification to the commit log v2: * changed clk2 to clk_cd * disable clk if clk_cd enable fails * changed clock name from "carddetect" to "cd" --- drivers/mmc/host/sh_mobile_sdhi.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c index 59db14b..d964a0d 100644 --- a/drivers/mmc/host/sh_mobile_sdhi.c +++ b/drivers/mmc/host/sh_mobile_sdhi.c @@ -143,6 +143,7 @@ MODULE_DEVICE_TABLE(of, sh_mobile_sdhi_of_match); struct sh_mobile_sdhi { struct clk *clk; + struct clk *clk_cd; struct tmio_mmc_data mmc_data; struct tmio_mmc_dma dma_priv; struct pinctrl *pinctrl; @@ -190,6 +191,12 @@ static int sh_mobile_sdhi_clk_enable(struct tmio_mmc_host *host) if (ret < 0) return ret; + ret = clk_prepare_enable(priv->clk_cd); + if (ret < 0) { + clk_disable_unprepare(priv->clk); + return ret; + } + /* * The clock driver may not know what maximum frequency * actually works, so it should be set with the max-frequency @@ -255,6 +262,7 @@ static void sh_mobile_sdhi_clk_disable(struct tmio_mmc_host *host) struct sh_mobile_sdhi *priv = host_to_priv(host); clk_disable_unprepare(priv->clk); + clk_disable_unprepare(priv->clk_cd); } static int sh_mobile_sdhi_card_busy(struct mmc_host *mmc) @@ -572,6 +580,21 @@ static int sh_mobile_sdhi_probe(struct platform_device *pdev) goto eprobe; } + /* + * Some controllers provide a 2nd clock just to run the internal card + * detection logic. Unfortunately, the existing driver architecture does + * not support a separation of clocks for runtime PM usage. When + * native hotplug is used, the tmio driver assumes that the core + * must continue to run for card detect to stay active, so we cannot + * disable it. + * Additionally, it is prohibited to supply a clock to the core but not + * to the card detect circuit. That leaves us with if separate clocks + * are presented, we must treat them both as virtually 1 clock. + */ + priv->clk_cd = devm_clk_get(&pdev->dev, "cd"); + if (IS_ERR(priv->clk_cd)) + priv->clk_cd = NULL; + priv->pinctrl = devm_pinctrl_get(&pdev->dev); if (!IS_ERR(priv->pinctrl)) { priv->pins_default = pinctrl_lookup_state(priv->pinctrl,