From patchwork Mon Jun 2 09:09:55 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Srinivas Kandagatla X-Patchwork-Id: 4280641 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3CDA9BEEA7 for ; Mon, 2 Jun 2014 09:11:24 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6A85B202EB for ; Mon, 2 Jun 2014 09:11:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8963420158 for ; Mon, 2 Jun 2014 09:11:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753705AbaFBJKF (ORCPT ); Mon, 2 Jun 2014 05:10:05 -0400 Received: from mail-we0-f177.google.com ([74.125.82.177]:64372 "EHLO mail-we0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753690AbaFBJKC (ORCPT ); Mon, 2 Jun 2014 05:10:02 -0400 Received: by mail-we0-f177.google.com with SMTP id x48so4641003wes.8 for ; Mon, 02 Jun 2014 02:10:00 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=f9qQR8hnKanvTi/6BjuJyPcepbdporSonwldRDOPIWU=; b=OJfqU1OZl5FJKnOhGh1eBwe8Z5PbdmxwTt+Wj7OfnXvGKsx1Us6lzs24U4G3MPQS5J s+KrYEScsjLM2Vb/qMXE90vDBVC3mF8XjykvdbIG/3QMxzh8Gfrn65uMJAtM2KqwCD36 M19S1BzlH9ip16UDESq0dXkjsRkAMdQL4vCsEPOcQcMqHCsKODZUVkfDM7wkKAtgTj/K bRCDXVhTkNZq7PIA4GvXUtUWvz1mCDZCV0X/uKcFtasvEV8vobiaIFIjB82YBXosGLmd WGshMG6dx4ICUxjWfFLB9Cz8chmlTOUDFY6lt4ye8Zx0mDbQ6eNxvHhr//nsZ7iJjoHa 0A3A== X-Gm-Message-State: ALoCoQlZZX9OfgdeDtw/tL9pCyaTXaX2ikdZVVfbvidZMYydKd4ppBo+9tKQWZSbnroaAhKZ1mRe X-Received: by 10.180.8.136 with SMTP id r8mr20112794wia.60.1401700200641; Mon, 02 Jun 2014 02:10:00 -0700 (PDT) Received: from srini-ThinkPad-X1-Carbon-2nd.dlink.com (host-78-149-12-106.as13285.net. [78.149.12.106]) by mx.google.com with ESMTPSA id s9sm30829832wix.13.2014.06.02.02.09.58 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 02 Jun 2014 02:09:59 -0700 (PDT) From: srinivas.kandagatla@linaro.org To: Russell King , Ulf Hansson , linux-mmc@vger.kernel.org Cc: Chris Ball , linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linus.walleij@linaro.org, Srinivas Kandagatla Subject: [PATCH v6 10/12] mmc: mmci: add explicit clk control Date: Mon, 2 Jun 2014 10:09:55 +0100 Message-Id: <1401700195-11834-1-git-send-email-srinivas.kandagatla@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1401699818-11329-1-git-send-email-srinivas.kandagatla@linaro.org> References: <1401699818-11329-1-git-send-email-srinivas.kandagatla@linaro.org> Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Srinivas Kandagatla On Controllers like Qcom SD card controller where cclk is mclk and mclk should be directly controlled by the driver. This patch adds support to control mclk directly in the driver, and also adds explicit_mclk_control flag in variant structure giving more flexibility to the driver. Signed-off-by: Srinivas Kandagatla Reviewed-by: Linus Walleij --- drivers/mmc/host/mmci.c | 30 +++++++++++++++++++++++++++--- drivers/mmc/host/mmci.h | 2 ++ 2 files changed, 29 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index 55d39d2..08715ab 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -72,6 +72,7 @@ static unsigned int fmax = 515633; * @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock * @busy_detect: true if busy detection on dat0 is supported * @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply + * @explicit_mclk_control: enable explicit mclk control in driver. */ struct variant_data { unsigned int clkreg; @@ -93,6 +94,7 @@ struct variant_data { bool pwrreg_clkgate; bool busy_detect; bool pwrreg_nopower; + bool explicit_mclk_control; }; static struct variant_data variant_arm = { @@ -286,7 +288,9 @@ static void mmci_set_clkreg(struct mmci_host *host, unsigned int desired) host->cclk = 0; if (desired) { - if (desired >= host->mclk) { + if (variant->explicit_mclk_control) { + host->cclk = host->mclk; + } else if (desired >= host->mclk) { clk = MCI_CLK_BYPASS; if (variant->st_clkdiv) clk |= MCI_ST_UX500_NEG_EDGE; @@ -1325,6 +1329,18 @@ static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) if (!ios->clock && variant->pwrreg_clkgate) pwr &= ~MCI_PWR_ON; + if (host->variant->explicit_mclk_control && + ios->clock != host->clock_cache) { + int rc = clk_set_rate(host->clk, ios->clock); + if (rc < 0) { + dev_err(mmc_dev(host->mmc), + "Error setting clock rate (%d)\n", rc); + } else { + host->mclk = clk_get_rate(host->clk); + host->clock_cache = ios->clock; + } + } + spin_lock_irqsave(&host->lock, flags); mmci_set_clkreg(host, ios->clock); @@ -1500,9 +1516,12 @@ static int mmci_probe(struct amba_device *dev, * The ARM and ST versions of the block have slightly different * clock divider equations which means that the minimum divider * differs too. + * on Qualcomm like controllers get the nearest minimum clock to 100Khz */ if (variant->st_clkdiv) mmc->f_min = DIV_ROUND_UP(host->mclk, 257); + else if (variant->explicit_mclk_control) + mmc->f_min = clk_round_rate(host->clk, 100000); else mmc->f_min = DIV_ROUND_UP(host->mclk, 512); /* @@ -1512,9 +1531,14 @@ static int mmci_probe(struct amba_device *dev, * the block, of course. */ if (mmc->f_max) - mmc->f_max = min(host->mclk, mmc->f_max); + mmc->f_max = variant->explicit_mclk_control ? + min(variant->f_max, mmc->f_max) : + min(host->mclk, mmc->f_max); else - mmc->f_max = min(host->mclk, fmax); + mmc->f_max = variant->explicit_mclk_control ? + fmax : min(host->mclk, fmax); + + dev_dbg(mmc_dev(mmc), "clocking block at %u Hz\n", mmc->f_max); /* Get regulators and the supported OCR mask */ diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h index d38a99d..ef34617 100644 --- a/drivers/mmc/host/mmci.h +++ b/drivers/mmc/host/mmci.h @@ -208,6 +208,8 @@ struct mmci_host { spinlock_t lock; unsigned int mclk; + /* cached value of requested clk in set_ios */ + unsigned int clock_cache; unsigned int cclk; u32 pwr_reg; u32 pwr_reg_add;