2 * Synopsys DesignWare I2C adapter driver (master only).
4 * Based on the TI DAVINCI I2C adapter driver.
6 * Copyright (C) 2006 Texas Instruments.
7 * Copyright (C) 2007 MontaVista Software Inc.
8 * Copyright (C) 2009 Provigent Ltd.
10 * ----------------------------------------------------------------------------
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 * ----------------------------------------------------------------------------
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/delay.h>
31 #include <linux/i2c.h>
32 #include <linux/clk.h>
33 #include <linux/errno.h>
34 #include <linux/sched.h>
35 #include <linux/err.h>
36 #include <linux/interrupt.h>
37 #include <linux/of_i2c.h>
38 #include <linux/platform_device.h>
40 #include <linux/slab.h>
41 #include "i2c-designware-core.h"
43 static struct i2c_algorithm i2c_dw_algo = {
44 .master_xfer = i2c_dw_xfer,
45 .functionality = i2c_dw_func,
47 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
49 return clk_get_rate(dev->clk)/1000;
52 static int __devinit dw_i2c_probe(struct platform_device *pdev)
54 struct dw_i2c_dev *dev;
55 struct i2c_adapter *adap;
56 struct resource *mem, *ioarea;
59 /* NOTE: driver uses the static register mapping */
60 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
62 dev_err(&pdev->dev, "no mem resource?\n");
66 irq = platform_get_irq(pdev, 0);
68 dev_err(&pdev->dev, "no irq resource?\n");
69 return irq; /* -ENXIO */
72 ioarea = request_mem_region(mem->start, resource_size(mem),
75 dev_err(&pdev->dev, "I2C region already claimed\n");
79 dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL);
82 goto err_release_region;
85 init_completion(&dev->cmd_complete);
86 mutex_init(&dev->lock);
87 dev->dev = get_device(&pdev->dev);
89 platform_set_drvdata(pdev, dev);
91 dev->clk = clk_get(&pdev->dev, NULL);
92 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
94 if (IS_ERR(dev->clk)) {
102 I2C_FUNC_10BIT_ADDR |
103 I2C_FUNC_SMBUS_BYTE |
104 I2C_FUNC_SMBUS_BYTE_DATA |
105 I2C_FUNC_SMBUS_WORD_DATA |
106 I2C_FUNC_SMBUS_I2C_BLOCK;
107 dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
108 DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
110 dev->base = ioremap(mem->start, resource_size(mem));
111 if (dev->base == NULL) {
112 dev_err(&pdev->dev, "failure mapping io resources\n");
114 goto err_unuse_clocks;
117 u32 param1 = i2c_dw_read_comp_param(dev);
119 dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
120 dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
122 r = i2c_dw_init(dev);
126 i2c_dw_disable_int(dev);
127 r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev);
129 dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
133 adap = &dev->adapter;
134 i2c_set_adapdata(adap, dev);
135 adap->owner = THIS_MODULE;
136 adap->class = I2C_CLASS_HWMON;
137 strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
139 adap->algo = &i2c_dw_algo;
140 adap->dev.parent = &pdev->dev;
141 adap->dev.of_node = pdev->dev.of_node;
144 r = i2c_add_numbered_adapter(adap);
146 dev_err(&pdev->dev, "failure adding adapter\n");
149 of_i2c_register_devices(adap);
154 free_irq(dev->irq, dev);
158 clk_disable(dev->clk);
162 platform_set_drvdata(pdev, NULL);
163 put_device(&pdev->dev);
166 release_mem_region(mem->start, resource_size(mem));
171 static int __devexit dw_i2c_remove(struct platform_device *pdev)
173 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
174 struct resource *mem;
176 platform_set_drvdata(pdev, NULL);
177 i2c_del_adapter(&dev->adapter);
178 put_device(&pdev->dev);
180 clk_disable(dev->clk);
185 free_irq(dev->irq, dev);
188 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
189 release_mem_region(mem->start, resource_size(mem));
194 static const struct of_device_id dw_i2c_of_match[] = {
195 { .compatible = "snps,designware-i2c", },
198 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
201 /* work with hotplug and coldplug */
202 MODULE_ALIAS("platform:i2c_designware");
204 static struct platform_driver dw_i2c_driver = {
205 .remove = __devexit_p(dw_i2c_remove),
207 .name = "i2c_designware",
208 .owner = THIS_MODULE,
209 .of_match_table = of_match_ptr(dw_i2c_of_match),
213 static int __init dw_i2c_init_driver(void)
215 return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
217 subsys_initcall(dw_i2c_init_driver);
219 static void __exit dw_i2c_exit_driver(void)
221 platform_driver_unregister(&dw_i2c_driver);
223 module_exit(dw_i2c_exit_driver);
225 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
226 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
227 MODULE_LICENSE("GPL");