drivers/i2c/busses/i2c-designware-platdrv.c - arm/linux - Git at Google

 /*
  * Synopsys DesignWare I2C adapter driver (master only).
  *
  * Based on the TI DAVINCI I2C adapter driver.
  *
  * Copyright (C) 2006 Texas Instruments.
  * Copyright (C) 2007 MontaVista Software Inc.
  * Copyright (C) 2009 Provigent Ltd.
  *
  * ----------------------------------------------------------------------------
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  * ----------------------------------------------------------------------------
  *
  */
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/i2c.h>
 #include <linux/clk.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/err.h>
 #include <linux/interrupt.h>
 #include <linux/of.h>
 #include <linux/of_i2c.h>
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
 #include "i2c-designware-core.h"

 static struct i2c_algorithm i2c_dw_algo = {
 	.master_xfer	= i2c_dw_xfer,
 	.functionality	= i2c_dw_func,
 };
 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
 {
 	return clk_get_rate(dev->clk)/1000;
 }

 #ifdef CONFIG_ACPI
 static int dw_i2c_acpi_configure(struct platform_device *pdev)
 {
 	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);

 	if (!ACPI_HANDLE(&pdev->dev))
 		return -ENODEV;

 	dev->adapter.nr = -1;
 	dev->tx_fifo_depth = 32;
 	dev->rx_fifo_depth = 32;
 	return 0;
 }

 static const struct acpi_device_id dw_i2c_acpi_match[] = {
 	{ "INT33C2", 0 },
 	{ "INT33C3", 0 },
 	{ "80860F41", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
 #else
 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
 {
 	return -ENODEV;
 }
 #endif

 static int dw_i2c_probe(struct platform_device *pdev)
 {
 	struct dw_i2c_dev *dev;
 	struct i2c_adapter *adap;
 	struct resource *mem;
 	int irq, r;

 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
 		dev_err(&pdev->dev, "no irq resource?\n");
 		return irq; /* -ENXIO */
 	}

 	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
 	if (!dev)
 		return -ENOMEM;

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

 	init_completion(&dev->cmd_complete);
 	mutex_init(&dev->lock);
 	dev->dev = &pdev->dev;
 	dev->irq = irq;
 	platform_set_drvdata(pdev, dev);

 	dev->clk = devm_clk_get(&pdev->dev, NULL);
 	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;

 	if (IS_ERR(dev->clk))
 		return PTR_ERR(dev->clk);
 	clk_prepare_enable(dev->clk);

 	if (pdev->dev.of_node) {
 		u32 ht = 0;
 		u32 ic_clk = dev->get_clk_rate_khz(dev);

 		of_property_read_u32(pdev->dev.of_node,
 					"i2c-sda-hold-time-ns", &ht);
 		dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000,
 					     1000000);
 	}

 	dev->functionality =
 		I2C_FUNC_I2C |
 		I2C_FUNC_10BIT_ADDR |
 		I2C_FUNC_SMBUS_BYTE |
 		I2C_FUNC_SMBUS_BYTE_DATA |
 		I2C_FUNC_SMBUS_WORD_DATA |
 		I2C_FUNC_SMBUS_I2C_BLOCK;
 	dev->master_cfg =  DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
 		DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;

 	/* Try first if we can configure the device from ACPI */
 	r = dw_i2c_acpi_configure(pdev);
 	if (r) {
 		u32 param1 = i2c_dw_read_comp_param(dev);

 		dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
 		dev->rx_fifo_depth = ((param1 >> 8)  & 0xff) + 1;
 		dev->adapter.nr = pdev->id;
 	}
 	r = i2c_dw_init(dev);
 	if (r)
 		return r;

 	i2c_dw_disable_int(dev);
 	r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
 			pdev->name, dev);
 	if (r) {
 		dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
 		return r;
 	}

 	adap = &dev->adapter;
 	i2c_set_adapdata(adap, dev);
 	adap->owner = THIS_MODULE;
 	adap->class = I2C_CLASS_HWMON;
 	strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
 			sizeof(adap->name));
 	adap->algo = &i2c_dw_algo;
 	adap->dev.parent = &pdev->dev;
 	adap->dev.of_node = pdev->dev.of_node;

 	r = i2c_add_numbered_adapter(adap);
 	if (r) {
 		dev_err(&pdev->dev, "failure adding adapter\n");
 		return r;
 	}
 	of_i2c_register_devices(adap);
 	acpi_i2c_register_devices(adap);

 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_active(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);

 	return 0;
 }

 static int dw_i2c_remove(struct platform_device *pdev)
 {
 	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);

 	pm_runtime_get_sync(&pdev->dev);

 	i2c_del_adapter(&dev->adapter);

 	i2c_dw_disable(dev);

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

 	return 0;
 }

 #ifdef CONFIG_OF
 static const struct of_device_id dw_i2c_of_match[] = {
 	{ .compatible = "snps,designware-i2c", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
 #endif

 #ifdef CONFIG_PM
 static int dw_i2c_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);

 	clk_disable_unprepare(i_dev->clk);

 	return 0;
 }

 static int dw_i2c_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);

 	clk_prepare_enable(i_dev->clk);
 	i2c_dw_init(i_dev);

 	return 0;
 }
 #endif

 static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume);

 /* work with hotplug and coldplug */
 MODULE_ALIAS("platform:i2c_designware");

 static struct platform_driver dw_i2c_driver = {
 	.remove		= dw_i2c_remove,
 	.driver		= {
 		.name	= "i2c_designware",
 		.owner	= THIS_MODULE,
 		.of_match_table = of_match_ptr(dw_i2c_of_match),
 		.acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 		.pm	= &dw_i2c_dev_pm_ops,
 	},
 };

 static int __init dw_i2c_init_driver(void)
 {
 	return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
 }
 subsys_initcall(dw_i2c_init_driver);

 static void __exit dw_i2c_exit_driver(void)
 {
 	platform_driver_unregister(&dw_i2c_driver);
 }
 module_exit(dw_i2c_exit_driver);

 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
 MODULE_LICENSE("GPL");
	/*
	* Synopsys DesignWare I2C adapter driver (master only).
	*
	* Based on the TI DAVINCI I2C adapter driver.
	*
	* Copyright (C) 2006 Texas Instruments.
	* Copyright (C) 2007 MontaVista Software Inc.
	* Copyright (C) 2009 Provigent Ltd.
	*
	* ----------------------------------------------------------------------------
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	* ----------------------------------------------------------------------------
	*
	*/
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/delay.h>
	#include <linux/i2c.h>
	#include <linux/clk.h>
	#include <linux/errno.h>
	#include <linux/sched.h>
	#include <linux/err.h>
	#include <linux/interrupt.h>
	#include <linux/of.h>
	#include <linux/of_i2c.h>
	#include <linux/platform_device.h>
	#include <linux/pm.h>
	#include <linux/pm_runtime.h>
	#include <linux/io.h>
	#include <linux/slab.h>
	#include <linux/acpi.h>
	#include "i2c-designware-core.h"

	static struct i2c_algorithm i2c_dw_algo = {
	.master_xfer = i2c_dw_xfer,
	.functionality = i2c_dw_func,
	};
	static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
	{
	return clk_get_rate(dev->clk)/1000;
	}

	#ifdef CONFIG_ACPI
	static int dw_i2c_acpi_configure(struct platform_device *pdev)
	{
	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);

	if (!ACPI_HANDLE(&pdev->dev))
	return -ENODEV;

	dev->adapter.nr = -1;
	dev->tx_fifo_depth = 32;
	dev->rx_fifo_depth = 32;
	return 0;
	}

	static const struct acpi_device_id dw_i2c_acpi_match[] = {
	{ "INT33C2", 0 },
	{ "INT33C3", 0 },
	{ "80860F41", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
	#else
	static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
	{
	return -ENODEV;
	}
	#endif

	static int dw_i2c_probe(struct platform_device *pdev)
	{
	struct dw_i2c_dev *dev;
	struct i2c_adapter *adap;
	struct resource *mem;
	int irq, r;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
	dev_err(&pdev->dev, "no irq resource?\n");
	return irq; /* -ENXIO */
	}

	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
	if (!dev)
	return -ENOMEM;

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

	init_completion(&dev->cmd_complete);
	mutex_init(&dev->lock);
	dev->dev = &pdev->dev;
	dev->irq = irq;
	platform_set_drvdata(pdev, dev);

	dev->clk = devm_clk_get(&pdev->dev, NULL);
	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;

	if (IS_ERR(dev->clk))
	return PTR_ERR(dev->clk);
	clk_prepare_enable(dev->clk);

	if (pdev->dev.of_node) {
	u32 ht = 0;
	u32 ic_clk = dev->get_clk_rate_khz(dev);

	of_property_read_u32(pdev->dev.of_node,
	"i2c-sda-hold-time-ns", &ht);
	dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000,
	1000000);
	}

	dev->functionality =
	I2C_FUNC_I2C \|
	I2C_FUNC_10BIT_ADDR \|
	I2C_FUNC_SMBUS_BYTE \|
	I2C_FUNC_SMBUS_BYTE_DATA \|
	I2C_FUNC_SMBUS_WORD_DATA \|
	I2C_FUNC_SMBUS_I2C_BLOCK;
	dev->master_cfg = DW_IC_CON_MASTER \| DW_IC_CON_SLAVE_DISABLE \|
	DW_IC_CON_RESTART_EN \| DW_IC_CON_SPEED_FAST;

	/* Try first if we can configure the device from ACPI */
	r = dw_i2c_acpi_configure(pdev);
	if (r) {
	u32 param1 = i2c_dw_read_comp_param(dev);

	dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
	dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
	dev->adapter.nr = pdev->id;
	}
	r = i2c_dw_init(dev);
	if (r)
	return r;

	i2c_dw_disable_int(dev);
	r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
	pdev->name, dev);
	if (r) {
	dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
	return r;
	}

	adap = &dev->adapter;
	i2c_set_adapdata(adap, dev);
	adap->owner = THIS_MODULE;
	adap->class = I2C_CLASS_HWMON;
	strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
	sizeof(adap->name));
	adap->algo = &i2c_dw_algo;
	adap->dev.parent = &pdev->dev;
	adap->dev.of_node = pdev->dev.of_node;

	r = i2c_add_numbered_adapter(adap);
	if (r) {
	dev_err(&pdev->dev, "failure adding adapter\n");
	return r;
	}
	of_i2c_register_devices(adap);
	acpi_i2c_register_devices(adap);

	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
	pm_runtime_use_autosuspend(&pdev->dev);
	pm_runtime_set_active(&pdev->dev);
	pm_runtime_enable(&pdev->dev);

	return 0;
	}

	static int dw_i2c_remove(struct platform_device *pdev)
	{
	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);

	pm_runtime_get_sync(&pdev->dev);

	i2c_del_adapter(&dev->adapter);

	i2c_dw_disable(dev);

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

	return 0;
	}

	#ifdef CONFIG_OF
	static const struct of_device_id dw_i2c_of_match[] = {
	{ .compatible = "snps,designware-i2c", },
	{},
	};
	MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
	#endif

	#ifdef CONFIG_PM
	static int dw_i2c_suspend(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);

	clk_disable_unprepare(i_dev->clk);

	return 0;
	}

	static int dw_i2c_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);

	clk_prepare_enable(i_dev->clk);
	i2c_dw_init(i_dev);

	return 0;
	}
	#endif

	static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume);

	/* work with hotplug and coldplug */
	MODULE_ALIAS("platform:i2c_designware");

	static struct platform_driver dw_i2c_driver = {
	.remove = dw_i2c_remove,
	.driver = {
	.name = "i2c_designware",
	.owner = THIS_MODULE,
	.of_match_table = of_match_ptr(dw_i2c_of_match),
	.acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
	.pm = &dw_i2c_dev_pm_ops,
	},
	};

	static int __init dw_i2c_init_driver(void)
	{
	return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
	}
	subsys_initcall(dw_i2c_init_driver);

	static void __exit dw_i2c_exit_driver(void)
	{
	platform_driver_unregister(&dw_i2c_driver);
	}
	module_exit(dw_i2c_exit_driver);

	MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
	MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
	MODULE_LICENSE("GPL");