From patchwork Thu Mar 9 06:42:08 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiner Kallweit X-Patchwork-Id: 736851 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3vf1lM5cTfz9sNK for ; Thu, 9 Mar 2017 18:11:11 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="ExWR/Vug"; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752447AbdCIHLL (ORCPT ); Thu, 9 Mar 2017 02:11:11 -0500 Received: from mail-wr0-f195.google.com ([209.85.128.195]:35716 "EHLO mail-wr0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751355AbdCIHLK (ORCPT ); Thu, 9 Mar 2017 02:11:10 -0500 Received: by mail-wr0-f195.google.com with SMTP id u108so6747659wrb.2 for ; Wed, 08 Mar 2017 23:11:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=3UVrOL7pq5HQ1ycHwqFQIeNRiblp2VPNSWrWyoIkNYs=; b=ExWR/Vuges3StOU8OnIL+ysvvH7oiNqx1JHqLThToCoBzKZOseR6E6qIegHQJGN+Sb Ax8yhO155pILYHqtSkSd6IUHoFLz6COCy3QJDqJRqMG6EAf++FtVTm+E/Kyl2hPsKGbh Dq+7GMMmEyAAVocD2X0GOtgasN3afYdYJVl2hnffyC8D9oiVkoqbHa+sMY1jTM4e2+HJ 5KtnXtvMEtzpq8UIfP95nPA4iqVtUSqpzjg2BKnbAvFkrVTbJmRbnqGKPdk/dTqf17Zq YMExI9yrTqaxXk0xl/tlUYWsEHqvob1RG4NVhVyRhN0szwCBnQNbmVxco7u1TqIZXfo/ DBow== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=3UVrOL7pq5HQ1ycHwqFQIeNRiblp2VPNSWrWyoIkNYs=; b=cxEH9xxmJtZp3P44P3q6EE0hfWEFMK+LENKFFJ6TdjkaKecDoSxSw1NU05ABwrU0ey jpaR2kt5LDBYaVi0L6kzeB9qZuTFrD7N1qtefL8VIGsjPy5J4zVPthL7gMnRD3XuIwBp a3dtIqX0MHgMu6Jx9PYNS8hH0ELogAxkdpYu2YCA6NaSJW/C5VYeOiqREn6uKDQ1ie5C s1hNRmLTR+e05HhcYeD0OL961jmkYszMP5DeKjm1mff0K7MWydAH1ystMfWGyst7+zXA r1lpx+DOQRkNXLA0HGolgsl52aC+K9AuyRSIlO/j7OTw+Y4J44j2SgWQhUhJyRiJEs1X QwqQ== X-Gm-Message-State: AMke39leme4s+WB0XrcpdUeT8qaVxzAeEM+Aqm9PvEezjIRo+cQw/SZFhSXvjDPXBcyfNQ== X-Received: by 10.223.139.83 with SMTP id v19mr8670961wra.142.1489042904598; Wed, 08 Mar 2017 23:01:44 -0800 (PST) Received: from ?IPv6:2003:c6:ebdc:4000:b589:624b:5134:aa75? (p200300C6EBDC4000B589624B5134AA75.dip0.t-ipconnect.de. [2003:c6:ebdc:4000:b589:624b:5134:aa75]) by smtp.googlemail.com with ESMTPSA id o15sm26075142wmd.10.2017.03.08.23.01.43 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 08 Mar 2017 23:01:44 -0800 (PST) Subject: [PATCH v2 05/10] i2c: meson: set clock divider in probe instead of setting it for each transfer To: Wolfram Sang , Jerome Brunet References: Cc: "linux-i2c@vger.kernel.org" , linux-amlogic@lists.infradead.org From: Heiner Kallweit Message-ID: <5fcfa996-5986-1856-d6f7-a979b7c5d5c9@gmail.com> Date: Thu, 9 Mar 2017 07:42:08 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org The bus frequency won't change, therefore we can set the clock divider in probe already and we don't have to set it for each transfer. Signed-off-by: Heiner Kallweit --- v2: - no changes --- drivers/i2c/busses/i2c-meson.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c index a5764be5..594fec22 100644 --- a/drivers/i2c/busses/i2c-meson.c +++ b/drivers/i2c/busses/i2c-meson.c @@ -74,7 +74,6 @@ enum { * @error: Flag set when an error is received * @lock: To avoid race conditions between irq handler and xfer code * @done: Completion used to wait for transfer termination - * @timings: Struct including the bus frequency * @tokens: Sequence of tokens to be written to the device * @num_tokens: Number of tokens */ @@ -93,7 +92,6 @@ struct meson_i2c { spinlock_t lock; struct completion done; - struct i2c_timings timings; u32 tokens[2]; int num_tokens; }; @@ -132,12 +130,12 @@ static void meson_i2c_write_tokens(struct meson_i2c *i2c) writel(i2c->tokens[1], i2c->regs + REG_TOK_LIST1); } -static void meson_i2c_set_clk_div(struct meson_i2c *i2c) +static void meson_i2c_set_clk_div(struct meson_i2c *i2c, unsigned int freq) { unsigned long clk_rate = clk_get_rate(i2c->clk); unsigned int div; - div = DIV_ROUND_UP(clk_rate, i2c->timings.bus_freq_hz * 4); + div = DIV_ROUND_UP(clk_rate, freq * 4); /* clock divider has 12 bits */ WARN_ON(div >= (1 << 12)); @@ -149,7 +147,7 @@ static void meson_i2c_set_clk_div(struct meson_i2c *i2c) (div >> 10) << REG_CTRL_CLKDIVEXT_SHIFT); dev_dbg(i2c->dev, "%s: clk %lu, freq %u, div %u\n", __func__, - clk_rate, i2c->timings.bus_freq_hz, div); + clk_rate, freq, div); } static void meson_i2c_get_data(struct meson_i2c *i2c, char *buf, int len) @@ -369,7 +367,6 @@ static int meson_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int i, ret = 0, count = 0; clk_enable(i2c->clk); - meson_i2c_set_clk_div(i2c); for (i = 0; i < num; i++) { ret = meson_i2c_xfer_msg(i2c, msgs + i, i == num - 1); @@ -396,6 +393,7 @@ static const struct i2c_algorithm meson_i2c_algorithm = { static int meson_i2c_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; + struct i2c_timings timings; struct meson_i2c *i2c; struct resource *mem; int irq, ret = 0; @@ -404,7 +402,7 @@ static int meson_i2c_probe(struct platform_device *pdev) if (!i2c) return -ENOMEM; - i2c_parse_fw_timings(&pdev->dev, &i2c->timings, true); + i2c_parse_fw_timings(&pdev->dev, &timings, true); i2c->dev = &pdev->dev; platform_set_drvdata(pdev, i2c); @@ -462,6 +460,8 @@ static int meson_i2c_probe(struct platform_device *pdev) return ret; } + meson_i2c_set_clk_div(i2c, timings.bus_freq_hz); + return 0; }