[media] exynos4-is: Add FIMC-IS ISP I2C bus driver

/*

 * Samsung EXYNOS4x12 FIMC-IS (Imaging Subsystem) driver

 *

 * Copyright (C) 2013 Samsung Electronics Co., Ltd.

 *

 * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

#include <linux/clk.h>

#include <linux/module.h>

#include <linux/of_i2c.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>

#include <linux/slab.h>

#include "fimc-is-i2c.h"

struct fimc_is_i2c {

	struct i2c_adapter adapter;

	struct clk *clock;

};

/*

 * An empty algorithm is used as the actual I2C bus controller driver

 * is implemented in the FIMC-IS subsystem firmware and the host CPU

 * doesn't access the I2C bus controller.

 */

static const struct i2c_algorithm fimc_is_i2c_algorithm;

static int fimc_is_i2c_probe(struct platform_device *pdev)

{

	struct device_node *node = pdev->dev.of_node;

	struct fimc_is_i2c *isp_i2c;

	struct i2c_adapter *i2c_adap;

	int ret;

	isp_i2c = devm_kzalloc(&pdev->dev, sizeof(*isp_i2c), GFP_KERNEL);

	if (!isp_i2c)

		return -ENOMEM;

	isp_i2c->clock = devm_clk_get(&pdev->dev, "i2c_isp");

	if (IS_ERR(isp_i2c->clock)) {

		dev_err(&pdev->dev, "failed to get the clock\n");

		return PTR_ERR(isp_i2c->clock);

	}

	i2c_adap = &isp_i2c->adapter;

	i2c_adap->dev.of_node = node;

	i2c_adap->dev.parent = &pdev->dev;

	strlcpy(i2c_adap->name, "exynos4x12-isp-i2c", sizeof(i2c_adap->name));

	i2c_adap->owner = THIS_MODULE;

	i2c_adap->algo = &fimc_is_i2c_algorithm;

	i2c_adap->class = I2C_CLASS_SPD;

	ret = i2c_add_adapter(i2c_adap);

	if (ret < 0) {

		dev_err(&pdev->dev, "failed to add I2C bus %s\n",

						node->full_name);

		return ret;

	}

	platform_set_drvdata(pdev, isp_i2c);

	pm_runtime_enable(&pdev->dev);

	pm_runtime_enable(&i2c_adap->dev);

	of_i2c_register_devices(i2c_adap);

	return 0;

}

static int fimc_is_i2c_remove(struct platform_device *pdev)

{

	struct fimc_is_i2c *isp_i2c = platform_get_drvdata(pdev);

	pm_runtime_disable(&isp_i2c->adapter.dev);

	pm_runtime_disable(&pdev->dev);

	i2c_del_adapter(&isp_i2c->adapter);

	return 0;

}

static int fimc_is_i2c_suspend(struct device *dev)

{

	struct fimc_is_i2c *isp_i2c = dev_get_drvdata(dev);

	clk_disable_unprepare(isp_i2c->clock);

	return 0;

}

static int fimc_is_i2c_resume(struct device *dev)

{

	struct fimc_is_i2c *isp_i2c = dev_get_drvdata(dev);

	return clk_prepare_enable(isp_i2c->clock);

}

UNIVERSAL_DEV_PM_OPS(fimc_is_i2c_pm_ops, fimc_is_i2c_suspend,

		     fimc_is_i2c_resume, NULL);

static const struct of_device_id fimc_is_i2c_of_match[] = {

	{ .compatible = FIMC_IS_I2C_COMPATIBLE },

	{ },

};

MODULE_DEVICE_TABLE(of, fimc_is_i2c_of_match);

static struct platform_driver fimc_is_i2c_driver = {

	.probe		= fimc_is_i2c_probe,

	.remove		= fimc_is_i2c_remove,

	.driver = {

		.of_match_table = fimc_is_i2c_of_match,

		.name		= "fimc-isp-i2c",

		.owner		= THIS_MODULE,

		.pm		= &fimc_is_i2c_pm_ops,

	}

};

int fimc_is_register_i2c_driver(void)

{

	return platform_driver_register(&fimc_is_i2c_driver);

}

EXPORT_SYMBOL(fimc_is_register_i2c_driver);

void fimc_is_unregister_i2c_driver(void)

{

	platform_driver_unregister(&fimc_is_i2c_driver);

}

EXPORT_SYMBOL(fimc_is_unregister_i2c_driver);

/*

 * Samsung EXYNOS4x12 FIMC-IS (Imaging Subsystem) driver

 *

 * Copyright (C) 2013 Samsung Electronics Co., Ltd.

 * Sylwester Nawrocki <s.nawrocki@samsung.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

#define FIMC_IS_I2C_COMPATIBLE	"samsung,exynos4212-i2c-isp"

int fimc_is_register_i2c_driver(void);

void fimc_is_unregister_i2c_driver(void);