i2c-imx.c

	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;

	i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
			PINCTRL_STATE_DEFAULT);
	i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
			"gpio");
	rinfo->sda_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
			"sda-gpios", 0, NULL);
	rinfo->scl_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
			"scl-gpios", 0, NULL);

	if (!gpio_is_valid(rinfo->sda_gpio) ||
	    !gpio_is_valid(rinfo->scl_gpio) ||
	    IS_ERR(i2c_imx->pinctrl_pins_default) ||
	    IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
		dev_dbg(&pdev->dev, "recovery information incomplete\n");
		return;
	}

	dev_dbg(&pdev->dev, "using scl-gpio %d and sda-gpio %d for recovery\n",
			rinfo->sda_gpio, rinfo->scl_gpio);

	rinfo->prepare_recovery = i2c_imx_prepare_recovery;
	rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
	rinfo->recover_bus = i2c_generic_gpio_recovery;
	i2c_imx->adapter.bus_recovery_info = rinfo;
}

static u32 i2c_imx_func(struct i2c_adapter *adapter)
{
	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
		| I2C_FUNC_SMBUS_READ_BLOCK_DATA;
}

static struct i2c_algorithm i2c_imx_algo = {
	.master_xfer	= i2c_imx_xfer,
	.functionality	= i2c_imx_func,
};

static int i2c_imx_probe(struct platform_device *pdev)
{
	const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids,
							   &pdev->dev);
	struct imx_i2c_struct *i2c_imx;
	struct resource *res;
	struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
	void __iomem *base;
	int irq, ret;
	dma_addr_t phy_addr;

	dev_dbg(&pdev->dev, "<%s>\n", __func__);

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_err(&pdev->dev, "can't get irq number\n");
		return irq;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(base))
		return PTR_ERR(base);

	phy_addr = (dma_addr_t)res->start;
	i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL);
	if (!i2c_imx)
		return -ENOMEM;

	if (of_id)
		i2c_imx->hwdata = of_id->data;
	else
		i2c_imx->hwdata = (struct imx_i2c_hwdata *)
				platform_get_device_id(pdev)->driver_data;

	/* Setup i2c_imx driver structure */
	strlcpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name));
	i2c_imx->adapter.owner		= THIS_MODULE;
	i2c_imx->adapter.algo		= &i2c_imx_algo;
	i2c_imx->adapter.dev.parent	= &pdev->dev;
	i2c_imx->adapter.nr		= pdev->id;
	i2c_imx->adapter.dev.of_node	= pdev->dev.of_node;
	i2c_imx->base			= base;

	/* Get I2C clock */
	i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(i2c_imx->clk)) {
		dev_err(&pdev->dev, "can't get I2C clock\n");
		return PTR_ERR(i2c_imx->clk);
	}

	ret = clk_prepare_enable(i2c_imx->clk);
	if (ret) {
		dev_err(&pdev->dev, "can't enable I2C clock, ret=%d\n", ret);
		return ret;
	}

	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
	if (IS_ERR(i2c_imx->pinctrl)) {
		ret = PTR_ERR(i2c_imx->pinctrl);
		goto clk_disable;
	}

	/* Request IRQ */
	ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
				pdev->name, i2c_imx);
	if (ret) {
		dev_err(&pdev->dev, "can't claim irq %d\n", irq);
		goto clk_disable;
	}

	/* Init queue */
	init_waitqueue_head(&i2c_imx->queue);

	/* Set up adapter data */
	i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);

	/* Set up platform driver data */
	platform_set_drvdata(pdev, i2c_imx);

	pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
	pm_runtime_use_autosuspend(&pdev->dev);
	pm_runtime_set_active(&pdev->dev);
	pm_runtime_enable(&pdev->dev);

	ret = pm_runtime_get_sync(&pdev->dev);
	if (ret < 0)
		goto rpm_disable;

	/* Set up clock divider */
	i2c_imx->bitrate = IMX_I2C_BIT_RATE;
	ret = of_property_read_u32(pdev->dev.of_node,
				   "clock-frequency", &i2c_imx->bitrate);
	if (ret < 0 && pdata && pdata->bitrate)
		i2c_imx->bitrate = pdata->bitrate;

	/* Set up chip registers to defaults */
	imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
			i2c_imx, IMX_I2C_I2CR);
	imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);

	i2c_imx_init_recovery_info(i2c_imx, pdev);

	/* Add I2C adapter */
	ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
	if (ret < 0) {
		dev_err(&pdev->dev, "registration failed\n");
		goto rpm_disable;
	}

	pm_runtime_mark_last_busy(&pdev->dev);
	pm_runtime_put_autosuspend(&pdev->dev);

	dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq);
	dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
	dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
		i2c_imx->adapter.name);
	dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");

	/* Init DMA config if supported */
	i2c_imx_dma_request(i2c_imx, phy_addr);

	return 0;   /* Return OK */

rpm_disable:
	pm_runtime_put_noidle(&pdev->dev);
	pm_runtime_disable(&pdev->dev);
	pm_runtime_set_suspended(&pdev->dev);
	pm_runtime_dont_use_autosuspend(&pdev->dev);

clk_disable:
	clk_disable_unprepare(i2c_imx->clk);
	return ret;
}

static int i2c_imx_remove(struct platform_device *pdev)
{
	struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
	int ret;

	ret = pm_runtime_get_sync(&pdev->dev);
	if (ret < 0)
		return ret;

	/* remove adapter */
	dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
	i2c_del_adapter(&i2c_imx->adapter);

	if (i2c_imx->dma)
		i2c_imx_dma_free(i2c_imx);

	/* setup chip registers to defaults */
	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR);
	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);

	clk_disable_unprepare(i2c_imx->clk);

	pm_runtime_put_noidle(&pdev->dev);
	pm_runtime_disable(&pdev->dev);

	return 0;
}

#ifdef CONFIG_PM
static int i2c_imx_runtime_suspend(struct device *dev)
{
	struct imx_i2c_struct *i2c_imx  = dev_get_drvdata(dev);

	clk_disable_unprepare(i2c_imx->clk);

	return 0;
}

static int i2c_imx_runtime_resume(struct device *dev)
{
	struct imx_i2c_struct *i2c_imx  = dev_get_drvdata(dev);
	int ret;

	ret = clk_prepare_enable(i2c_imx->clk);
	if (ret)
		dev_err(dev, "can't enable I2C clock, ret=%d\n", ret);

	return ret;
}

static const struct dev_pm_ops i2c_imx_pm_ops = {
	SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend,
			   i2c_imx_runtime_resume, NULL)
};
#define I2C_IMX_PM_OPS (&i2c_imx_pm_ops)
#else
#define I2C_IMX_PM_OPS NULL
#endif /* CONFIG_PM */

static struct platform_driver i2c_imx_driver = {
	.probe = i2c_imx_probe,
	.remove = i2c_imx_remove,
	.driver = {
		.name = DRIVER_NAME,
		.pm = I2C_IMX_PM_OPS,
		.of_match_table = i2c_imx_dt_ids,
	},
	.id_table = imx_i2c_devtype,
};

static int __init i2c_adap_imx_init(void)
{
	return platform_driver_register(&i2c_imx_driver);
}
subsys_initcall(i2c_adap_imx_init);

static void __exit i2c_adap_imx_exit(void)
{
	platform_driver_unregister(&i2c_imx_driver);
}
module_exit(i2c_adap_imx_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Darius Augulis");
MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
MODULE_ALIAS("platform:" DRIVER_NAME);