drivers/qtn/i2cbus/i2c-qtn-platdrv.c - kernel/quantenna - Git at Google

 /*
  * Quantenna 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.
  * Copyright (C) 2014 Quantenna Communications Inc.
  *
  * ----------------------------------------------------------------------------
  *
  * 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/version.h>
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/i2c.h>
 #include <linux/clk.h>
 #include <linux/gpio.h>
 #include <linux/errno.h>
 #include <linux/sched.h>
 #include <linux/err.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <asm/board/platform.h>
 #include <asm/board/clock.h>
 #include <ruby/gpio.h>
 #include "i2c-qtn-core.h"

 static int i2c_xfer_noop = 0;

 static int qtn_i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 {
 	if (i2c_xfer_noop) {
 		return -EAGAIN;
 	}

 	return i2c_dw_xfer(adap, msgs, num);
 }

 static struct i2c_algorithm i2c_dw_algo = {
 	.master_xfer	= qtn_i2c_dw_xfer,
 	.functionality	= i2c_dw_func,
 };
 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
 {
 	return qtn_clk_get_rate(dev->clk)/1000;
 }

 static int dw_i2c_probe(struct platform_device *pdev)
 {
 	struct dw_i2c_dev *dev;
 	struct i2c_adapter *adap;
 	struct resource *mem = NULL;
 	unsigned long mem_res_size = 0;
 	int irq, r;
 	u32 param1;

 	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;

 #ifndef TOPAZ_AMBER_IP
 	r = gpio_request(RUBY_GPIO_I2C_SCL, "i2c-scl");
 	if (r) {
 			dev_err(&pdev->dev, "fail to request gpio i2c scl pin #%d\n", RUBY_GPIO_I2C_SCL);
 			goto fail_ret;
 	}

 	r = gpio_request(RUBY_GPIO_I2C_SDA, "i2c-sda");
 	if (r) {
 			dev_err(&pdev->dev, "fail to request gpio i2c sda pin #%d\n", RUBY_GPIO_I2C_SDA);
 			goto fail_ret;
 	}

 	gpio_config(RUBY_GPIO_I2C_SCL, RUBY_GPIO_ALT_INPUT);
 	gpio_config(RUBY_GPIO_I2C_SDA, RUBY_GPIO_ALT_INPUT);
 #else
 	/*
 	 * In Amber GPIO pins are not shared. No need to set up alternate function.
 	 */
 #endif

 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!mem) {
 		dev_err(&pdev->dev, "couldn't get memory resource\n");
 		r = -ENODEV;
 		goto fail_ret;
 	}
 	mem_res_size = resource_size(mem);

 	if (!devm_request_mem_region(&pdev->dev, mem->start, mem_res_size, pdev->name)) {
 		dev_err(&pdev->dev, "can't request region for resource %pR\n", mem);
 		mem = NULL;
 		r = -EBUSY;
 		goto fail_ret;
 	}

 	dev->base = devm_ioremap_nocache(&pdev->dev, mem->start, mem_res_size);
 	if (IS_ERR(dev->base)) {
 		dev_err(&pdev->dev, "failed to map controller\n");
 		r = PTR_ERR(dev->base);
 		goto fail_ret;
 	}

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

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

 	if (IS_ERR(dev->clk)) {
 		dev_err(&pdev->dev, "no clk found\n");
 		r = PTR_ERR(dev->clk);
 		goto fail_ret;
 	}

 	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;

 	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)
 		goto fail_ret;

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

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

 	r = i2c_add_numbered_adapter(adap);
 	if (r) {
 		dev_err(&pdev->dev, "failure adding adapter\n");
 		free_irq(dev->irq, dev);
 		goto fail_ret;
 	}

 	return 0;

 fail_ret:
 	if (dev->base)
 		devm_iounmap(&pdev->dev, dev->base);

 	if (mem)
 		devm_release_mem_region(&pdev->dev, mem->start, mem_res_size);

 	kfree(dev);
 	return r;
 }

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

 	free_irq(dev->irq, dev);
 	i2c_del_adapter(&dev->adapter);

 	i2c_dw_disable(dev);

 #ifndef TOPAZ_AMBER_IP
 	gpio_free(RUBY_GPIO_I2C_SCL);
 	gpio_free(RUBY_GPIO_I2C_SDA);
 #else
 	/*
 	 * In Amber GPIO pins are not shared. No need to set up alternate function.
 	 */
 #endif

 	return 0;
 }

 static ssize_t qtn_i2c_xfer_noop_show(struct device_driver *ddrv, char *buf)
 {
 	return sprintf(buf, "%d\n", i2c_xfer_noop);
 }

 static ssize_t qtn_i2c_xfer_noop_store(struct device_driver *ddrv, const char *buf, size_t count)
 {
 	if (count > 0) {
 		i2c_xfer_noop = (buf[0] == '1');
 	}
 	if (i2c_xfer_noop) {
 		pr_info("%s suppressing i2c bus activity\n", ddrv->name);
 	}
 	return count;
 }

 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4,7,0)
 DRIVER_ATTR(i2c_xfer_noop, S_IRUSR | S_IWUSR, qtn_i2c_xfer_noop_show, qtn_i2c_xfer_noop_store);
 #else
 DRIVER_ATTR(i2c_xfer_noop, S_IRUGO | S_IWUGO, qtn_i2c_xfer_noop_show, qtn_i2c_xfer_noop_store);
 #endif

 static struct platform_driver qtn_i2c_driver = {
 	.probe = dw_i2c_probe,
 	.remove = dw_i2c_remove,
 	.driver		= {
 		.name	= "qtn-i2c",
 		.owner	= THIS_MODULE,
 	},
 };

 static int __init qtn_i2c_init_driver(void)
 {
 	int ret;

 	ret = platform_driver_probe(&qtn_i2c_driver, dw_i2c_probe);
 	if (ret < 0) {
 		return ret;
 	}

 	if (driver_create_file(&qtn_i2c_driver.driver, &driver_attr_i2c_xfer_noop) < 0) {
 		pr_err("qtn-i2c %s: could not register sysfs driver file\n", __FUNCTION__);
 	}

 	return 0;
 }
 module_init(qtn_i2c_init_driver);

 static void __exit dw_i2c_exit_driver(void)
 {
 	driver_remove_file(&qtn_i2c_driver.driver, &driver_attr_i2c_xfer_noop);
 	platform_driver_unregister(&qtn_i2c_driver);
 }
 module_exit(dw_i2c_exit_driver);

 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 MODULE_AUTHOR("Quantenna Communications");
 MODULE_DESCRIPTION("Quantenna I2C Adapter");
 MODULE_LICENSE("GPL");
	/*
	* Quantenna 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.
	* Copyright (C) 2014 Quantenna Communications Inc.
	*
	* ----------------------------------------------------------------------------
	*
	* 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/version.h>
	#include <linux/module.h>
	#include <linux/delay.h>
	#include <linux/i2c.h>
	#include <linux/clk.h>
	#include <linux/gpio.h>
	#include <linux/errno.h>
	#include <linux/sched.h>
	#include <linux/err.h>
	#include <linux/interrupt.h>
	#include <linux/platform_device.h>
	#include <linux/io.h>
	#include <linux/slab.h>
	#include <asm/board/platform.h>
	#include <asm/board/clock.h>
	#include <ruby/gpio.h>
	#include "i2c-qtn-core.h"

	static int i2c_xfer_noop = 0;

	static int qtn_i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
	{
	if (i2c_xfer_noop) {
	return -EAGAIN;
	}

	return i2c_dw_xfer(adap, msgs, num);
	}

	static struct i2c_algorithm i2c_dw_algo = {
	.master_xfer = qtn_i2c_dw_xfer,
	.functionality = i2c_dw_func,
	};
	static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
	{
	return qtn_clk_get_rate(dev->clk)/1000;
	}

	static int dw_i2c_probe(struct platform_device *pdev)
	{
	struct dw_i2c_dev *dev;
	struct i2c_adapter *adap;
	struct resource *mem = NULL;
	unsigned long mem_res_size = 0;
	int irq, r;
	u32 param1;

	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;

	#ifndef TOPAZ_AMBER_IP
	r = gpio_request(RUBY_GPIO_I2C_SCL, "i2c-scl");
	if (r) {
	dev_err(&pdev->dev, "fail to request gpio i2c scl pin #%d\n", RUBY_GPIO_I2C_SCL);
	goto fail_ret;
	}

	r = gpio_request(RUBY_GPIO_I2C_SDA, "i2c-sda");
	if (r) {
	dev_err(&pdev->dev, "fail to request gpio i2c sda pin #%d\n", RUBY_GPIO_I2C_SDA);
	goto fail_ret;
	}

	gpio_config(RUBY_GPIO_I2C_SCL, RUBY_GPIO_ALT_INPUT);
	gpio_config(RUBY_GPIO_I2C_SDA, RUBY_GPIO_ALT_INPUT);
	#else
	/*
	* In Amber GPIO pins are not shared. No need to set up alternate function.
	*/
	#endif

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem) {
	dev_err(&pdev->dev, "couldn't get memory resource\n");
	r = -ENODEV;
	goto fail_ret;
	}
	mem_res_size = resource_size(mem);

	if (!devm_request_mem_region(&pdev->dev, mem->start, mem_res_size, pdev->name)) {
	dev_err(&pdev->dev, "can't request region for resource %pR\n", mem);
	mem = NULL;
	r = -EBUSY;
	goto fail_ret;
	}

	dev->base = devm_ioremap_nocache(&pdev->dev, mem->start, mem_res_size);
	if (IS_ERR(dev->base)) {
	dev_err(&pdev->dev, "failed to map controller\n");
	r = PTR_ERR(dev->base);
	goto fail_ret;
	}

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

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

	if (IS_ERR(dev->clk)) {
	dev_err(&pdev->dev, "no clk found\n");
	r = PTR_ERR(dev->clk);
	goto fail_ret;
	}

	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;

	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)
	goto fail_ret;

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

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

	r = i2c_add_numbered_adapter(adap);
	if (r) {
	dev_err(&pdev->dev, "failure adding adapter\n");
	free_irq(dev->irq, dev);
	goto fail_ret;
	}

	return 0;

	fail_ret:
	if (dev->base)
	devm_iounmap(&pdev->dev, dev->base);

	if (mem)
	devm_release_mem_region(&pdev->dev, mem->start, mem_res_size);

	kfree(dev);
	return r;
	}

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

	free_irq(dev->irq, dev);
	i2c_del_adapter(&dev->adapter);

	i2c_dw_disable(dev);

	#ifndef TOPAZ_AMBER_IP
	gpio_free(RUBY_GPIO_I2C_SCL);
	gpio_free(RUBY_GPIO_I2C_SDA);
	#else
	/*
	* In Amber GPIO pins are not shared. No need to set up alternate function.
	*/
	#endif

	return 0;
	}

	static ssize_t qtn_i2c_xfer_noop_show(struct device_driver ddrv, char buf)
	{
	return sprintf(buf, "%d\n", i2c_xfer_noop);
	}

	static ssize_t qtn_i2c_xfer_noop_store(struct device_driver ddrv, const char buf, size_t count)
	{
	if (count > 0) {
	i2c_xfer_noop = (buf[0] == '1');
	}
	if (i2c_xfer_noop) {
	pr_info("%s suppressing i2c bus activity\n", ddrv->name);
	}
	return count;
	}

	#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,7,0)
	DRIVER_ATTR(i2c_xfer_noop, S_IRUSR \| S_IWUSR, qtn_i2c_xfer_noop_show, qtn_i2c_xfer_noop_store);
	#else
	DRIVER_ATTR(i2c_xfer_noop, S_IRUGO \| S_IWUGO, qtn_i2c_xfer_noop_show, qtn_i2c_xfer_noop_store);
	#endif

	static struct platform_driver qtn_i2c_driver = {
	.probe = dw_i2c_probe,
	.remove = dw_i2c_remove,
	.driver = {
	.name = "qtn-i2c",
	.owner = THIS_MODULE,
	},
	};

	static int __init qtn_i2c_init_driver(void)
	{
	int ret;

	ret = platform_driver_probe(&qtn_i2c_driver, dw_i2c_probe);
	if (ret < 0) {
	return ret;
	}

	if (driver_create_file(&qtn_i2c_driver.driver, &driver_attr_i2c_xfer_noop) < 0) {
	pr_err("qtn-i2c %s: could not register sysfs driver file\n", __FUNCTION__);
	}

	return 0;
	}
	module_init(qtn_i2c_init_driver);

	static void __exit dw_i2c_exit_driver(void)
	{
	driver_remove_file(&qtn_i2c_driver.driver, &driver_attr_i2c_xfer_noop);
	platform_driver_unregister(&qtn_i2c_driver);
	}
	module_exit(dw_i2c_exit_driver);

	MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
	MODULE_AUTHOR("Quantenna Communications");
	MODULE_DESCRIPTION("Quantenna I2C Adapter");
	MODULE_LICENSE("GPL");