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>
38 #include <linux/of_i2c.h>
39 #include <linux/platform_device.h>
41 #include <linux/pm_runtime.h>
43 #include <linux/slab.h>
44 #include <linux/acpi.h>
45 #include "i2c-designware-core.h"
47 static struct i2c_algorithm i2c_dw_algo = {
48 .master_xfer = i2c_dw_xfer,
49 .functionality = i2c_dw_func,
51 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
53 return clk_get_rate(dev->clk)/1000;
57 static int dw_i2c_acpi_configure(struct platform_device *pdev)
59 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
61 if (!ACPI_HANDLE(&pdev->dev))
65 dev->tx_fifo_depth = 32;
66 dev->rx_fifo_depth = 32;
70 static const struct acpi_device_id dw_i2c_acpi_match[] = {
76 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
78 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
84 static int dw_i2c_probe(struct platform_device *pdev)
86 struct dw_i2c_dev *dev;
87 struct i2c_adapter *adap;
91 irq = platform_get_irq(pdev, 0);
93 dev_err(&pdev->dev, "no irq resource?\n");
94 return irq; /* -ENXIO */
97 dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
101 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
102 dev->base = devm_ioremap_resource(&pdev->dev, mem);
103 if (IS_ERR(dev->base))
104 return PTR_ERR(dev->base);
106 init_completion(&dev->cmd_complete);
107 mutex_init(&dev->lock);
108 dev->dev = &pdev->dev;
110 platform_set_drvdata(pdev, dev);
112 dev->clk = devm_clk_get(&pdev->dev, NULL);
113 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
115 if (IS_ERR(dev->clk))
116 return PTR_ERR(dev->clk);
117 clk_prepare_enable(dev->clk);
119 if (pdev->dev.of_node) {
121 u32 ic_clk = dev->get_clk_rate_khz(dev);
123 of_property_read_u32(pdev->dev.of_node,
124 "i2c-sda-hold-time-ns", &ht);
125 dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000,
131 I2C_FUNC_10BIT_ADDR |
132 I2C_FUNC_SMBUS_BYTE |
133 I2C_FUNC_SMBUS_BYTE_DATA |
134 I2C_FUNC_SMBUS_WORD_DATA |
135 I2C_FUNC_SMBUS_I2C_BLOCK;
136 dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
137 DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
139 /* Try first if we can configure the device from ACPI */
140 r = dw_i2c_acpi_configure(pdev);
142 u32 param1 = i2c_dw_read_comp_param(dev);
144 dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
145 dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
146 dev->adapter.nr = pdev->id;
148 r = i2c_dw_init(dev);
152 i2c_dw_disable_int(dev);
153 r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
156 dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
160 adap = &dev->adapter;
161 i2c_set_adapdata(adap, dev);
162 adap->owner = THIS_MODULE;
163 adap->class = I2C_CLASS_HWMON;
164 strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
166 adap->algo = &i2c_dw_algo;
167 adap->dev.parent = &pdev->dev;
168 adap->dev.of_node = pdev->dev.of_node;
170 r = i2c_add_numbered_adapter(adap);
172 dev_err(&pdev->dev, "failure adding adapter\n");
175 of_i2c_register_devices(adap);
176 acpi_i2c_register_devices(adap);
178 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
179 pm_runtime_use_autosuspend(&pdev->dev);
180 pm_runtime_set_active(&pdev->dev);
181 pm_runtime_enable(&pdev->dev);
186 static int dw_i2c_remove(struct platform_device *pdev)
188 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
190 pm_runtime_get_sync(&pdev->dev);
192 i2c_del_adapter(&dev->adapter);
196 pm_runtime_put(&pdev->dev);
197 pm_runtime_disable(&pdev->dev);
203 static const struct of_device_id dw_i2c_of_match[] = {
204 { .compatible = "snps,designware-i2c", },
207 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
211 static int dw_i2c_suspend(struct device *dev)
213 struct platform_device *pdev = to_platform_device(dev);
214 struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
216 clk_disable_unprepare(i_dev->clk);
221 static int dw_i2c_resume(struct device *dev)
223 struct platform_device *pdev = to_platform_device(dev);
224 struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
226 clk_prepare_enable(i_dev->clk);
233 static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume);
235 /* work with hotplug and coldplug */
236 MODULE_ALIAS("platform:i2c_designware");
238 static struct platform_driver dw_i2c_driver = {
239 .remove = dw_i2c_remove,
241 .name = "i2c_designware",
242 .owner = THIS_MODULE,
243 .of_match_table = of_match_ptr(dw_i2c_of_match),
244 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
245 .pm = &dw_i2c_dev_pm_ops,
249 static int __init dw_i2c_init_driver(void)
251 return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
253 subsys_initcall(dw_i2c_init_driver);
255 static void __exit dw_i2c_exit_driver(void)
257 platform_driver_unregister(&dw_i2c_driver);
259 module_exit(dw_i2c_exit_driver);
261 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
262 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
263 MODULE_LICENSE("GPL");