From patchwork Thu Apr 8 13:11:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linus Walleij X-Patchwork-Id: 12191065 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 0BBF7C433B4 for ; Thu, 8 Apr 2021 13:12:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CEC6B61154 for ; Thu, 8 Apr 2021 13:12:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231508AbhDHNMi (ORCPT ); Thu, 8 Apr 2021 09:12:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231474AbhDHNMh (ORCPT ); Thu, 8 Apr 2021 09:12:37 -0400 Received: from mail-lj1-x22b.google.com (mail-lj1-x22b.google.com [IPv6:2a00:1450:4864:20::22b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 83BFCC061761 for ; Thu, 8 Apr 2021 06:12:25 -0700 (PDT) Received: by mail-lj1-x22b.google.com with SMTP id z8so2168725ljm.12 for ; Thu, 08 Apr 2021 06:12:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=n+BE/ls2y9st49pyD89waC8wDozI9Ea/Mpt87FhjcNo=; b=kw3NapkTQ27jXn9jWYbeeDpaIVzhbrfRKlcFIYK9shi/Zh1Q5vcXsp1M5LrZMMExJn 51ezyf91LZ10qeBNOjRwpaedDb+lPG0KIeOF9FWZHh/y8hnKsoagyRkIvVH0XeGdqUXG jMobSES+lg2Agzx7FigEA/YAlWAP6MgtiChwscmU8lZwizKPM27IY/Okc4Jsy3wrD08I Lov59tMkIemFasjnij2Gqey7fpNSOzNXNIrTeOrpyAxsmP/Cm4LxmBAUbyQUPAwzhXlt QE/upTeXhLQGHXUKuoPAUDtR+8qN3JDN3CLM3Q8A9Tcg2jtohI+QuXp7VOozhUwafHPj 2hCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=n+BE/ls2y9st49pyD89waC8wDozI9Ea/Mpt87FhjcNo=; b=GsXllaGSZHJkHwhXmec0v1jweoGJ0IbzazFXOz9Qg3DHDPBLEYQ1ymzxoIiYwxLbDf fDE+pDe+1p9ANXHc495XXHZGGRE5vzVFiyK9GX3VEHrba5E9wejpzBlf6DNr2uF25+KX ZeKfSqpi9Q3lu2nCty5wDtcVuSV1h052qTiZwfs+5Cs2emRSNrF2sDXh2roVrQUnh3om ASPW8/9KclFzchUVilqpRPIxzYruTBFX23dRn1YWoxR9atzIxRkW7yWkhV5elfJrE8Ca KFs0whUZ32XOQKOVjkoLIQGVjk+8zjmxL2yF7OrB14gYv233fUSfKxfjGCAQtfH/MKAg dWjQ== X-Gm-Message-State: AOAM532iFNH4vy3Gpyvh7fwdx6Dn0K4Yyd9KaSMXhY4pK8BL4VcrlDAm gm2l3pCCYnCT+6JcI0z9bjZ3vQ== X-Google-Smtp-Source: ABdhPJygTfMDZ5mheXkfSeujRbvov6DXFah4qDiW9+6Kopcbd7BknAwqzBZBvJPYyCnGHAMn113MLw== X-Received: by 2002:a05:651c:119b:: with SMTP id w27mr5593776ljo.237.1617887543685; Thu, 08 Apr 2021 06:12:23 -0700 (PDT) Received: from localhost.localdomain (c-14cb225c.014-348-6c756e10.bbcust.telenor.se. [92.34.203.20]) by smtp.gmail.com with ESMTPSA id z7sm126936ljm.102.2021.04.08.06.12.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 08 Apr 2021 06:12:23 -0700 (PDT) From: Linus Walleij To: Ferruh Yigit , Dmitry Torokhov , Javier Martinez Canillas Cc: Henrik Rydberg , linux-input@vger.kernel.org, Linus Walleij Subject: [PATCH 5/8 v3] Input: cyttsp - Reduce reset pulse timings Date: Thu, 8 Apr 2021 15:11:50 +0200 Message-Id: <20210408131153.3446138-6-linus.walleij@linaro.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210408131153.3446138-1-linus.walleij@linaro.org> References: <20210408131153.3446138-1-linus.walleij@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org The data sheet for CY8CTMA340 specifies that the reset pulse shall be at least 1 ms. Specify 1-2 ms with usleep_range() to cut some slack for the scheduler. Curiously the datasheet does not specify how long we have to wait after a hard reset until the chip is up, but I have found a vendor tree (Samsung GT-S7710) that has code for this touch screen and there this is set to 5 ms so I use this with the same 1 ms fuzz. Reviewed-by: Javier Martinez Canillas Signed-off-by: Linus Walleij --- ChangeLog v1->v3: - Collect Javier's Reviewed-by --- drivers/input/touchscreen/cyttsp_core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/input/touchscreen/cyttsp_core.c b/drivers/input/touchscreen/cyttsp_core.c index 91f8f38b3f06..84f4f1c1a220 100644 --- a/drivers/input/touchscreen/cyttsp_core.c +++ b/drivers/input/touchscreen/cyttsp_core.c @@ -230,10 +230,16 @@ static int cyttsp_set_sysinfo_regs(struct cyttsp *ts) static void cyttsp_hard_reset(struct cyttsp *ts) { if (ts->reset_gpio) { + /* + * According to the CY8CTMA340 datasheet page 21, the external + * reset pulse width should be >= 1 ms. The datasheet does not + * specify how long we have to wait after reset but a vendor + * tree specifies 5 ms here. + */ gpiod_set_value_cansleep(ts->reset_gpio, 1); - msleep(CY_DELAY_DFLT); + usleep_range(1000, 2000); gpiod_set_value_cansleep(ts->reset_gpio, 0); - msleep(CY_DELAY_DFLT); + usleep_range(5000, 6000); } }