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/pm_runtime.h>
42 #include <linux/slab.h>
43 #include <linux/acpi.h>
44 #include "i2c-designware-core.h"
46 static struct i2c_algorithm i2c_dw_algo = {
47 .master_xfer = i2c_dw_xfer,
48 .functionality = i2c_dw_func,
50 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
52 return clk_get_rate(dev->clk)/1000;
56 static int dw_i2c_acpi_configure(struct platform_device *pdev)
58 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
60 if (!ACPI_HANDLE(&pdev->dev))
64 dev->tx_fifo_depth = 32;
65 dev->rx_fifo_depth = 32;
69 static const struct acpi_device_id dw_i2c_acpi_match[] = {
75 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
77 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
83 static int dw_i2c_probe(struct platform_device *pdev)
85 struct dw_i2c_dev *dev;
86 struct i2c_adapter *adap;
90 /* NOTE: driver uses the static register mapping */
91 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
93 dev_err(&pdev->dev, "no mem resource?\n");
97 irq = platform_get_irq(pdev, 0);
99 dev_err(&pdev->dev, "no irq resource?\n");
100 return irq; /* -ENXIO */
103 dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
107 dev->base = devm_ioremap_resource(&pdev->dev, mem);
108 if (IS_ERR(dev->base))
109 return PTR_ERR(dev->base);
111 init_completion(&dev->cmd_complete);
112 mutex_init(&dev->lock);
113 dev->dev = &pdev->dev;
115 platform_set_drvdata(pdev, dev);
117 dev->clk = devm_clk_get(&pdev->dev, NULL);
118 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
120 if (IS_ERR(dev->clk))
121 return PTR_ERR(dev->clk);
122 clk_prepare_enable(dev->clk);
126 I2C_FUNC_10BIT_ADDR |
127 I2C_FUNC_SMBUS_BYTE |
128 I2C_FUNC_SMBUS_BYTE_DATA |
129 I2C_FUNC_SMBUS_WORD_DATA |
130 I2C_FUNC_SMBUS_I2C_BLOCK;
131 dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
132 DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
134 /* Try first if we can configure the device from ACPI */
135 r = dw_i2c_acpi_configure(pdev);
137 u32 param1 = i2c_dw_read_comp_param(dev);
139 dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
140 dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
141 dev->adapter.nr = pdev->id;
143 r = i2c_dw_init(dev);
147 i2c_dw_disable_int(dev);
148 r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
151 dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
155 adap = &dev->adapter;
156 i2c_set_adapdata(adap, dev);
157 adap->owner = THIS_MODULE;
158 adap->class = I2C_CLASS_HWMON;
159 strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
161 adap->algo = &i2c_dw_algo;
162 adap->dev.parent = &pdev->dev;
163 adap->dev.of_node = pdev->dev.of_node;
165 r = i2c_add_numbered_adapter(adap);
167 dev_err(&pdev->dev, "failure adding adapter\n");
170 of_i2c_register_devices(adap);
171 acpi_i2c_register_devices(adap);
173 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
174 pm_runtime_use_autosuspend(&pdev->dev);
175 pm_runtime_set_active(&pdev->dev);
176 pm_runtime_enable(&pdev->dev);
181 static int dw_i2c_remove(struct platform_device *pdev)
183 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
185 pm_runtime_get_sync(&pdev->dev);
187 i2c_del_adapter(&dev->adapter);
191 pm_runtime_put(&pdev->dev);
192 pm_runtime_disable(&pdev->dev);
198 static const struct of_device_id dw_i2c_of_match[] = {
199 { .compatible = "snps,designware-i2c", },
202 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
206 static int dw_i2c_suspend(struct device *dev)
208 struct platform_device *pdev = to_platform_device(dev);
209 struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
211 clk_disable_unprepare(i_dev->clk);
216 static int dw_i2c_resume(struct device *dev)
218 struct platform_device *pdev = to_platform_device(dev);
219 struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
221 clk_prepare_enable(i_dev->clk);
228 static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume);
230 /* work with hotplug and coldplug */
231 MODULE_ALIAS("platform:i2c_designware");
233 static struct platform_driver dw_i2c_driver = {
234 .remove = dw_i2c_remove,
236 .name = "i2c_designware",
237 .owner = THIS_MODULE,
238 .of_match_table = of_match_ptr(dw_i2c_of_match),
239 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
240 .pm = &dw_i2c_dev_pm_ops,
244 static int __init dw_i2c_init_driver(void)
246 return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
248 subsys_initcall(dw_i2c_init_driver);
250 static void __exit dw_i2c_exit_driver(void)
252 platform_driver_unregister(&dw_i2c_driver);
254 module_exit(dw_i2c_exit_driver);
256 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
257 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
258 MODULE_LICENSE("GPL");