From patchwork Tue Aug 6 20:43:46 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gerhard Sittig X-Patchwork-Id: 2839596 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id F344DBF535 for ; Tue, 6 Aug 2013 20:47:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1D01D20184 for ; Tue, 6 Aug 2013 20:47:00 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2C6CB2017D for ; Tue, 6 Aug 2013 20:46:59 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V6o90-0006Ra-Qe; 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Tue, 6 Aug 2013 22:45:11 +0200 (CEST) X-Auth-Info: 8EWG9I6oATV7va4P6YueHefyVvmsVwgH8gj3PTyA57Y= Received: from localhost (host-82-135-33-74.customer.m-online.net [82.135.33.74]) by mail.mnet-online.de (Postfix) with ESMTPA; Tue, 6 Aug 2013 22:45:11 +0200 (CEST) From: Gerhard Sittig To: linuxppc-dev@lists.ozlabs.org, Anatolij Gustschin , Mike Turquette , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org Subject: [PATCH v4 06/31] i2c: mpc: cleanup clock API use Date: Tue, 6 Aug 2013 22:43:46 +0200 Message-Id: <1375821851-31609-7-git-send-email-gsi@denx.de> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1375821851-31609-1-git-send-email-gsi@denx.de> References: <1374495298-22019-1-git-send-email-gsi@denx.de> <1375821851-31609-1-git-send-email-gsi@denx.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130806_164534_130112_8EAE1620 X-CRM114-Status: GOOD ( 13.16 ) X-Spam-Score: -0.2 (/) Cc: Detlev Zundel , Wolfram Sang , Greg Kroah-Hartman , Gerhard Sittig , Rob Herring , Mark Brown , Marc Kleine-Budde , Pantelis Antoniou , David Woodhouse , Wolfgang Grandegger , Mauro Carvalho Chehab X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,KHOP_BIG_TO_CC, RCVD_IN_DNSWL_MED,RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP make the MPC I2C driver get, prepare and enable the peripheral clock during probe ('per' for access to the peripheral's registers); disable and unprepare the clock upon remove(), put is done by the devm approach; hold a reference to the clock over the period of use clock lookup is non-fatal in this implementation as not all platforms may provide clock specs in their device tree, but enable errors for specified clocks are considered fatal Signed-off-by: Gerhard Sittig --- drivers/i2c/busses/i2c-mpc.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c index 7607dc0..4b00dd0 100644 --- a/drivers/i2c/busses/i2c-mpc.c +++ b/drivers/i2c/busses/i2c-mpc.c @@ -21,6 +21,7 @@ #include #include +#include #include #include #include @@ -67,6 +68,7 @@ struct mpc_i2c { #ifdef CONFIG_PM u8 fdr, dfsrr; #endif + struct clk *clk_per; }; struct mpc_i2c_divider { @@ -623,6 +625,8 @@ static int fsl_i2c_probe(struct platform_device *op) u32 clock = MPC_I2C_CLOCK_LEGACY; int result = 0; int plen; + struct clk *clk; + int err; match = of_match_device(mpc_i2c_of_match, &op->dev); if (!match) @@ -653,6 +657,21 @@ static int fsl_i2c_probe(struct platform_device *op) } } + /* + * enable clock for the I2C peripheral (non fatal), + * keep a reference upon successful allocation + */ + clk = devm_clk_get(&op->dev, "per"); + if (!IS_ERR(clk)) { + err = clk_prepare_enable(clk); + if (err) { + dev_err(&op->dev, "failed to enable clock\n"); + goto fail_request; + } else { + i2c->clk_per = clk; + } + } + if (of_get_property(op->dev.of_node, "fsl,preserve-clocking", NULL)) { clock = MPC_I2C_CLOCK_PRESERVE; } else { @@ -696,6 +715,8 @@ static int fsl_i2c_probe(struct platform_device *op) return result; fail_add: + if (i2c->clk_per) + clk_disable_unprepare(i2c->clk_per); free_irq(i2c->irq, i2c); fail_request: irq_dispose_mapping(i2c->irq); @@ -711,6 +732,9 @@ static int fsl_i2c_remove(struct platform_device *op) i2c_del_adapter(&i2c->adap); + if (i2c->clk_per) + clk_disable_unprepare(i2c->clk_per); + if (i2c->irq) free_irq(i2c->irq, i2c);