From patchwork Wed Dec 10 20:58:03 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 5472381 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id A732E9F444 for ; Wed, 10 Dec 2014 21:02:01 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B99852018E for ; Wed, 10 Dec 2014 21:02:00 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D2CC22017D for ; Wed, 10 Dec 2014 21:01:59 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XyoMO-0005jd-VD; Wed, 10 Dec 2014 20:59:48 +0000 Received: from mail-ig0-x234.google.com ([2607:f8b0:4001:c05::234]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XyoLR-0004zP-Ah for linux-arm-kernel@lists.infradead.org; Wed, 10 Dec 2014 20:58:52 +0000 Received: by mail-ig0-f180.google.com with SMTP id h15so3676838igd.1 for ; Wed, 10 Dec 2014 12:58:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=b5vGNprpqtxmgYW6KvEIFdElsN0IQZWgImgimLrZPp0=; b=k6Z2yqEyUq+Cdn+1M3mrjRoWhN4vGAgsc82gqdAhSCQnO1LKElWvhJoJ3GmjRw5QRz G+DoSJbSdM80HR0R/r2gy9x89QadAaujXsm2WHgI28KsLZ4GUeAs/WcCIobVBSfUmMfK amhmzM3wg/fdc1WtVgZ8BaWp1Y9OqTv3GlMjA= 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=b5vGNprpqtxmgYW6KvEIFdElsN0IQZWgImgimLrZPp0=; b=iDYRCUjK7ewd2jM5s9Z6znOOC2Em+aRbWuPMKPrU6Ew+bfpQbrc7Pt2CZpGl8xgX18 Bz+LhNlqojWUWuqCCga/2o9S5VCYUQbazUuWKLYGA4izQYFe5qMtB0q7cpyJmIPfiLTw 5e2tqzmncTwvXuNAkEZr/yUwKRHCZ13Eqfuy1JMpYK4YFSKwJndXF527Dww1OC3vIUcn 8OnJwCsxJ0GGGeWFkRHQme4tjlugd27UsMfFbNoeErBVIO3ec0y84GGEfbQgH+hvlSHa FjJOrMre2GR4kaFG7VTF4NnPcBVjBis6hrMw2Dw/+6/Po9m9kyRpThEiuIhCvPJyS7s5 99GA== X-Gm-Message-State: ALoCoQlHuggTjI6kfwlV6t4Lt0mOriidTJxsu30P2UcHZupAAjzXy5X3Nmk45ErXeiSeSkNA8HXD X-Received: by 10.50.79.135 with SMTP id j7mr10243672igx.14.1418245108273; Wed, 10 Dec 2014 12:58:28 -0800 (PST) Received: from tictac.mtv.corp.google.com ([172.22.65.76]) by mx.google.com with ESMTPSA id m15sm2091454iom.44.2014.12.10.12.58.27 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 10 Dec 2014 12:58:27 -0800 (PST) From: Doug Anderson To: Ulf Hansson , Mark Brown , Heiko Stuebner , Jaehoon Chung , Seungwon Jeon Subject: [PATCH 2/4] mmc: core: Add mmc_regulator_set_vqmmc() Date: Wed, 10 Dec 2014 12:58:03 -0800 Message-Id: <1418245085-9754-2-git-send-email-dianders@chromium.org> X-Mailer: git-send-email 2.2.0.rc0.207.ga3a616c In-Reply-To: <1418245085-9754-1-git-send-email-dianders@chromium.org> References: <1418245085-9754-1-git-send-email-dianders@chromium.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141210_125849_446231_F19B81A7 X-CRM114-Status: GOOD ( 15.84 ) X-Spam-Score: -0.8 (/) Cc: andrew_gabbasov@mentor.com, Alexandru Stan , Andrew Bresticker , linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org, Doug Anderson , chris@printf.net, linux-rockchip@lists.infradead.org, tim.kryger@gmail.com, Alim Akhtar , adrian.hunter@intel.com, Sonny Rao , johan.rudholm@axis.com, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID, T_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 This adds logic to the MMC core to set VQMMC. This is expected to be called by MMC drivers like dw_mmc as part of (or instead of) their start_signal_voltage_switch() callback. A few notes: * When setting the signal voltage to 3.3V we do our best to make VQMMC and VMMC match. It's been reported that this makes some old cards happy since they were tested back in the day before UHS when VQMMC and VMMC were provided by the same regulator. A nice side effect of this is that we don't end up on the hairy edge of VQMMC (2.7V), which some EEs claim is a little too close to the minimum for comfort. * When setting the signal voltage to 1.8V or 1.2V we aim for that specific voltage instead of picking the lowest one in the range. * We very purposely don't print errors in mmc_regulator_set_vqmmc(). There are cases where the MMC core will try several different voltages and we don't want to pollute the logs. Signed-off-by: Doug Anderson --- drivers/mmc/core/core.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/mmc/host.h | 7 +++++++ 2 files changed, 60 insertions(+) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 9584bff..d0da480 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1333,6 +1333,59 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc, } EXPORT_SYMBOL_GPL(mmc_regulator_set_ocr); +static int mmc_regulator_set_voltage_if_supported(struct regulator *regulator, + int min_uV, int ideal_uV, + int max_uV) +{ + /* + * Check if supported first to avoid errors since we may try several + * signal levels during power up and don't want to show errors. + */ + if (!regulator_is_supported_voltage(regulator, min_uV, max_uV)) + return -EINVAL; + + return regulator_set_closest_voltage(regulator, min_uV, ideal_uV, + max_uV); +} + +/** + * mmc_regulator_set_vqmmc - Set VQMMC as per the ios + * + * For 3.3V signaling, we try to match vqmmc to vmmc as closely as possible. + * That will match the behavior of old boards where vqmmc and vmmc were supplied + * by the same supply. + * + * For 1.2V and 1.8V signaling we'll try to get as close as possible to the + * requested voltage. This is definitely a good idea for UHS where there's a + * separate regulator on the card that's trying to make 1.8V and it's best if + * we match. + * + * This function is expected to be used by a controller's + * start_signal_voltage_switch() function. + */ +int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios) +{ + /* If no vqmmc supply then we can't change the voltage */ + if (IS_ERR(mmc->supply.vqmmc)) + return -EINVAL; + + switch (ios->signal_voltage) { + case MMC_SIGNAL_VOLTAGE_120: + return mmc_regulator_set_voltage_if_supported( + mmc->supply.vqmmc, 1100000, 1200000, 1300000); + case MMC_SIGNAL_VOLTAGE_180: + return mmc_regulator_set_voltage_if_supported( + mmc->supply.vqmmc, 1700000, 1800000, 1950000); + case MMC_SIGNAL_VOLTAGE_330: + return mmc_regulator_set_voltage_if_supported( + mmc->supply.vqmmc, 2700000, + regulator_get_voltage(mmc->supply.vmmc), 3600000); + default: + return -EINVAL; + } +} +EXPORT_SYMBOL_GPL(mmc_regulator_set_vqmmc); + #endif /* CONFIG_REGULATOR */ int mmc_regulator_get_supply(struct mmc_host *mmc) diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 9f32270..524d6fc 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -416,6 +416,7 @@ int mmc_regulator_get_ocrmask(struct regulator *supply); int mmc_regulator_set_ocr(struct mmc_host *mmc, struct regulator *supply, unsigned short vdd_bit); +int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios); #else static inline int mmc_regulator_get_ocrmask(struct regulator *supply) { @@ -428,6 +429,12 @@ static inline int mmc_regulator_set_ocr(struct mmc_host *mmc, { return 0; } + +static inline int mmc_regulator_set_vqmmc(struct mmc_host *mmc, + struct mmc_ios *ios) +{ + return -EINVAL; +} #endif int mmc_regulator_get_supply(struct mmc_host *mmc);