From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net (mail-out.m-online.net [IPv6:2001:a60:0:28:0:1:25:1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 055EA2C0275 for ; Wed, 7 Aug 2013 06:45:17 +1000 (EST) 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> 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> Cc: Detlev Zundel , Wolfram Sang , Greg Kroah-Hartman , Gerhard Sittig , Rob Herring , Mark Brown , Marc Kleine-Budde , David Woodhouse , Wolfgang Grandegger , Mauro Carvalho Chehab List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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); -- 1.7.10.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: gsi@denx.de (Gerhard Sittig) Date: Tue, 6 Aug 2013 22:43:46 +0200 Subject: [PATCH v4 06/31] i2c: mpc: cleanup clock API use 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> Message-ID: <1375821851-31609-7-git-send-email-gsi@denx.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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); -- 1.7.10.4