From patchwork Thu Sep 2 21:51:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 12472931 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C248EC433EF for ; Thu, 2 Sep 2021 21:52:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF6746112E for ; Thu, 2 Sep 2021 21:52:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347750AbhIBVxf (ORCPT ); Thu, 2 Sep 2021 17:53:35 -0400 Received: from relay10.mail.gandi.net ([217.70.178.230]:37681 "EHLO relay10.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347728AbhIBVx3 (ORCPT ); Thu, 2 Sep 2021 17:53:29 -0400 Received: (Authenticated sender: miquel.raynal@bootlin.com) by relay10.mail.gandi.net (Postfix) with ESMTPSA id B680D240005; Thu, 2 Sep 2021 21:52:27 +0000 (UTC) From: Miquel Raynal To: Jonathan Cameron , Lars-Peter Clausen , Peter Meerwald-Stadler , Rob Herring , Dmitry Torokhov , Lee Jones , bcousson@baylibre.com, Tony Lindgren Cc: linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-input@vger.kernel.org, linux-omap@vger.kernel.org, Thomas Petazzoni , Vignesh Raghavendra , Lokesh Vutla , Tero Kristo , Ryan Barnett , Grygorii Strashko , Jason Reeder , Miquel Raynal Subject: [PATCH v2 21/46] mfd: ti_am335x_tscadc: Reorder the initialization steps Date: Thu, 2 Sep 2021 23:51:19 +0200 Message-Id: <20210902215144.507243-22-miquel.raynal@bootlin.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210902215144.507243-1-miquel.raynal@bootlin.com> References: <20210902215144.507243-1-miquel.raynal@bootlin.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org TI AM335X TRM [1] states that most of the configuration should be set in the control register in the first place, before actually enabling the hardware with the subsystem enable bit. So far only half of the configuration was made in the first step (before enabling the "subsystem"), which does not make really sense. Also, the probe and the resume patch were acting differently. Let's harmonize all this by following these steps: 1/ Configure the CLKDIV register 2/ Configure the CTRL register 3/ Configure the idle configuration 4/ Really enable the device by rewriting the CTRL register with the subsystem enable bit set. [1] https://www.ti.com/lit/pdf/spruh73 Signed-off-by: Miquel Raynal Reviewed-by: Jonathan Cameron --- drivers/mfd/ti_am335x_tscadc.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c index 5f189da99468..61f878c7593b 100644 --- a/drivers/mfd/ti_am335x_tscadc.c +++ b/drivers/mfd/ti_am335x_tscadc.c @@ -221,8 +221,6 @@ static int ti_tscadc_probe(struct platform_device *pdev) /* Set the control register bits */ ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID; - regmap_write(tscadc->regmap, REG_CTRL, ctrl); - if (tsc_wires > 0) { tscadc->tsc_wires = tsc_wires; if (tsc_wires == 5) @@ -230,6 +228,7 @@ static int ti_tscadc_probe(struct platform_device *pdev) else ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB; } + regmap_write(tscadc->regmap, REG_CTRL, ctrl); tscadc_idle_config(tscadc); @@ -315,9 +314,9 @@ static int __maybe_unused tscadc_resume(struct device *dev) pm_runtime_get_sync(dev); /* context restore */ - ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID; - regmap_write(tscadc->regmap, REG_CTRL, ctrl); + regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div); + ctrl = CNTRLREG_STEPCONFIGWRT | CNTRLREG_STEPID; if (tscadc->tsc_wires > 0) { if (tscadc->tsc_wires == 5) ctrl |= CNTRLREG_5WIRE | CNTRLREG_TSCENB; @@ -325,13 +324,13 @@ static int __maybe_unused tscadc_resume(struct device *dev) ctrl |= CNTRLREG_4WIRE | CNTRLREG_TSCENB; } + regmap_write(tscadc->regmap, REG_CTRL, ctrl); + tscadc_idle_config(tscadc); ctrl |= CNTRLREG_TSCSSENB; regmap_write(tscadc->regmap, REG_CTRL, ctrl); - regmap_write(tscadc->regmap, REG_CLKDIV, tscadc->clk_div); - return 0; }