From patchwork Thu Apr 16 16:36:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Vasut X-Patchwork-Id: 11493505 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 948F41871 for ; Thu, 16 Apr 2020 16:37:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 879B121D7E for ; Thu, 16 Apr 2020 16:37:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729697AbgDPQhD (ORCPT ); Thu, 16 Apr 2020 12:37:03 -0400 Received: from mail-out.m-online.net ([212.18.0.9]:46287 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728109AbgDPQhC (ORCPT ); Thu, 16 Apr 2020 12:37:02 -0400 Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 4934cq4K1Pz1r6R5; Thu, 16 Apr 2020 18:36:58 +0200 (CEST) Received: from localhost (dynscan1.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 4934cp4Bn5z1qr47; Thu, 16 Apr 2020 18:36:58 +0200 (CEST) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id ZoZDHDCLihue; Thu, 16 Apr 2020 18:36:57 +0200 (CEST) X-Auth-Info: 762ekcraQhPWqvLrHV+UHKpIstfAt+4zYBipCVN2Z4s= Received: from desktop.lan (ip-86-49-35-8.net.upcbroadband.cz [86.49.35.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Thu, 16 Apr 2020 18:36:57 +0200 (CEST) From: Marek Vasut To: linux-mmc@vger.kernel.org Cc: Marek Vasut , Alexandre Torgue , Linus Walleij , Ludovic Barre , Manivannan Sadhasivam , Maxime Coquelin , Patrice Chotard , Patrick Delaunay , Russell King , Ulf Hansson , linux-stm32@st-md-mailman.stormreply.com Subject: [PATCH V2 2/3] mmc: Return 1 from mmc_regulator_set_vqmmc() if switch skipped Date: Thu, 16 Apr 2020 18:36:48 +0200 Message-Id: <20200416163649.336967-2-marex@denx.de> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200416163649.336967-1-marex@denx.de> References: <20200416163649.336967-1-marex@denx.de> MIME-Version: 1.0 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org Adjust mmc_regulator_set_vqmmc() to return 1 if the voltage switch was skipped because the regulator voltage was already correct. This allows drivers to detect such condition and possibly skip various voltage switching extras. Signed-off-by: Marek Vasut Cc: Alexandre Torgue Cc: Linus Walleij Cc: Ludovic Barre Cc: Manivannan Sadhasivam Cc: Maxime Coquelin Cc: Patrice Chotard Cc: Patrick Delaunay Cc: Russell King Cc: Ulf Hansson Cc: linux-stm32@st-md-mailman.stormreply.com To: linux-mmc@vger.kernel.org --- V2: - Rename variable curr_voltage to current_uV - Update mmc_regulator_set_vqmmc() to handle the fact that mmc_regulator_set_voltage_if_supported() can return value > 0 --- drivers/mmc/core/regulator.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/core/regulator.c b/drivers/mmc/core/regulator.c index b6febbcf8978..96b1d15045d6 100644 --- a/drivers/mmc/core/regulator.c +++ b/drivers/mmc/core/regulator.c @@ -136,6 +136,8 @@ static int mmc_regulator_set_voltage_if_supported(struct regulator *regulator, int min_uV, int target_uV, int max_uV) { + int current_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. @@ -143,6 +145,14 @@ static int mmc_regulator_set_voltage_if_supported(struct regulator *regulator, if (!regulator_is_supported_voltage(regulator, min_uV, max_uV)) return -EINVAL; + /* + * The voltage is already set, no need to switch. + * Return 1 to indicate that no switch happened. + */ + current_uV = regulator_get_voltage(regulator); + if (current_uV == target_uV) + return 1; + return regulator_set_voltage_triplet(regulator, min_uV, target_uV, max_uV); } @@ -198,9 +208,10 @@ int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios) * voltage in two steps and try to stay close to vmmc * with a 0.3V tolerance at first. */ - if (!mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc, - min_uV, volt, max_uV)) - return 0; + ret = mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc, + min_uV, volt, max_uV); + if (ret >= 0) + return ret; return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc, 2700000, volt, 3600000);