Commit b3bfce2b authored by Gerhard Sittig's avatar Gerhard Sittig Committed by Wolfram Sang
Browse files

i2c: mpc: cleanup clock API use 



make the MPC I2C driver get, prepare and enable the gated clock item for
register access during probe; 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 failure to enable a
clock when specified is considered fatal

Signed-off-by: default avatarGerhard Sittig <gsi@denx.de>
Signed-off-by: default avatarAnatolij Gustschin <agust@denx.de>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 498c0146

drivers/i2c/busses/i2c-mpc.c

+24 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#include <linux/of_platform.h>

#include <linux/slab.h>



#include <linux/clk.h>

#include <linux/io.h>

#include <linux/fsl_devices.h>

#include <linux/i2c.h>
@@ -66,6 +67,7 @@ struct mpc_i2c { 
#ifdef CONFIG_PM_SLEEP

	u8 fdr, dfsrr;

#endif

	struct clk *clk_per;

};



struct mpc_i2c_divider {
@@ -622,6 +624,8 @@ static int fsl_i2c_probe(struct platform_device *op) 
	int result = 0;

	int plen;

	struct resource res;

	struct clk *clk;

	int err;



	match = of_match_device(mpc_i2c_of_match, &op->dev);

	if (!match)
@@ -652,6 +656,21 @@ 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, NULL);

	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 {
@@ -697,6 +716,8 @@ 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);
@@ -712,6 +733,9 @@ 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);

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