From mboxrd@z Thu Jan 1 00:00:00 1970 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=-12.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 96CD0C5DF9D for ; Thu, 29 Oct 2020 08:13:33 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2DD2D20720 for ; Thu, 29 Oct 2020 08:13:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="gaOJwxZk" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2DD2D20720 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0BCAD6E89C; Thu, 29 Oct 2020 08:13:03 +0000 (UTC) Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by gabe.freedesktop.org (Postfix) with ESMTPS id 105ED6E47A for ; Thu, 29 Oct 2020 01:11:59 +0000 (UTC) Received: by mail-pf1-x443.google.com with SMTP id 13so952844pfy.4 for ; Wed, 28 Oct 2020 18:11:59 -0700 (PDT) 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 :mime-version:content-transfer-encoding; bh=43Z65rMPFX7c5zSWXhXV75KBPOJpzYr19A/FVKbG0kQ=; b=gaOJwxZk2SVJy0xnoCB5dJaUR2mO3wYx5WgvqbszDB+92yPQcR+9mAXUCZ37z0UeLK qn+adoLcNXZKQXVDF6Q2qBOgMMVrEIcfvQO2IFKoAr3uHfs5WbIakf8WIKWYfs5yXDFe a2FALBeE2ogDfGw4nVwVwqvUEVweX9YoNCC2c= 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=43Z65rMPFX7c5zSWXhXV75KBPOJpzYr19A/FVKbG0kQ=; b=aS2QkAFZ7KVlMUovKJgITxJqXnZ63FdZwJpK4UpX5uP/BkPo5xqTMx/6tgh2/ypkmx Qr+8USYWf6a7JcaH2yUWuLqASV6keosBfJbJ+93w1rEHnudslk123ltay2kiyiyKehQI mFbiAov24bFRpLpBwq4Tb4PgaJqnJC9Udg+RrYNl6mBG8Au11BYont3rSfcrwA+Y4f5E MTvkP6irccMWW4oXfo1UB6bG7Xqg5SIgW68ghY60wTDMb/XzaekuHMBXcRFSlh+8sPV2 IHImsrLPmDZOfdubuQDnSExmc1Xuvkvos58YCFL4CLfjYyhyreLDuumhMYCIh/I05Lif fy+Q== X-Gm-Message-State: AOAM533et+y5OarVVgEC2DeU908+RbCz8a0vwMXr4ivQV21t4m36cu8H 3Sy5SSYHLYNoRQP5xD5buSJRhA== X-Google-Smtp-Source: ABdhPJwytjkLPYk5jIPzS5cqIs63+UiSyMI+LTRDpm9VkQgZeuEE+mrdjewTHVF7UHozLGy7FvTPrw== X-Received: by 2002:a62:1e43:0:b029:164:9ac2:f54e with SMTP id e64-20020a621e430000b02901649ac2f54emr1562015pfe.61.1603933918770; Wed, 28 Oct 2020 18:11:58 -0700 (PDT) Received: from smtp.gmail.com ([2620:15c:202:201:3e52:82ff:fe6c:83ab]) by smtp.gmail.com with ESMTPSA id e6sm781769pfn.190.2020.10.28.18.11.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Oct 2020 18:11:58 -0700 (PDT) From: Stephen Boyd To: Andrzej Hajda , Neil Armstrong Subject: [PATCH 2/4] drm/bridge: ti-sn65dsi86: Make polling a busy loop Date: Wed, 28 Oct 2020 18:11:52 -0700 Message-Id: <20201029011154.1515687-3-swboyd@chromium.org> X-Mailer: git-send-email 2.29.1.341.ge80a0c044ae-goog In-Reply-To: <20201029011154.1515687-1-swboyd@chromium.org> References: <20201029011154.1515687-1-swboyd@chromium.org> MIME-Version: 1.0 X-Mailman-Approved-At: Thu, 29 Oct 2020 08:12:48 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jernej Skrabec , Jonas Karlman , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Douglas Anderson , Sean Paul , Laurent Pinchart Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" There's no reason we need to wait here to poll a register over i2c. The i2c bus is inherently slow and delays are practically part of the protocol because we have to wait for the device to respond to any request for a register. Let's rely on the sleeping of the i2c controller instead of adding any sort of delay here in the bridge driver. Cc: Douglas Anderson Cc: Laurent Pinchart Cc: Jonas Karlman Cc: Jernej Skrabec Cc: Sean Paul Signed-off-by: Stephen Boyd --- drivers/gpu/drm/bridge/ti-sn65dsi86.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c index 87726b9e446f..8276fa50138f 100644 --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c @@ -881,9 +881,9 @@ static ssize_t ti_sn_aux_transfer(struct drm_dp_aux *aux, regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val | AUX_CMD_SEND); + /* Zero delay loop because i2c transactions are slow already */ ret = regmap_read_poll_timeout(pdata->regmap, SN_AUX_CMD_REG, val, - !(val & AUX_CMD_SEND), 200, - 50 * 1000); + !(val & AUX_CMD_SEND), 0, 50 * 1000); if (ret) return ret; -- Sent by a computer, using git, on the internet _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel