1 /* 2 * Synopsys DesignWare I2C adapter driver (master only). 3 * 4 * Based on the TI DAVINCI I2C adapter driver. 5 * 6 * Copyright (C) 2006 Texas Instruments. 7 * Copyright (C) 2007 MontaVista Software Inc. 8 * Copyright (C) 2009 Provigent Ltd. 9 * 10 * ---------------------------------------------------------------------------- 11 * 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. 16 * 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. 21 * 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 * ---------------------------------------------------------------------------- 26 * 27 */ 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> 39 #include <linux/pm.h> 40 #include <linux/pm_runtime.h> 41 #include <linux/io.h> 42 #include <linux/slab.h> 43 #include <linux/acpi.h> 44 #include "i2c-designware-core.h" 45 46 static struct i2c_algorithm i2c_dw_algo = { 47 .master_xfer = i2c_dw_xfer, 48 .functionality = i2c_dw_func, 49 }; 50 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev) 51 { 52 return clk_get_rate(dev->clk)/1000; 53 } 54 55 #ifdef CONFIG_ACPI 56 static int dw_i2c_acpi_configure(struct platform_device *pdev) 57 { 58 struct dw_i2c_dev *dev = platform_get_drvdata(pdev); 59 60 if (!ACPI_HANDLE(&pdev->dev)) 61 return -ENODEV; 62 63 dev->adapter.nr = -1; 64 dev->tx_fifo_depth = 32; 65 dev->rx_fifo_depth = 32; 66 return 0; 67 } 68 69 static const struct acpi_device_id dw_i2c_acpi_match[] = { 70 { "INT33C2", 0 }, 71 { "INT33C3", 0 }, 72 { "80860F41", 0 }, 73 { } 74 }; 75 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); 76 #else 77 static inline int dw_i2c_acpi_configure(struct platform_device *pdev) 78 { 79 return -ENODEV; 80 } 81 #endif 82 83 static int dw_i2c_probe(struct platform_device *pdev) 84 { 85 struct dw_i2c_dev *dev; 86 struct i2c_adapter *adap; 87 struct resource *mem; 88 int irq, r; 89 90 /* NOTE: driver uses the static register mapping */ 91 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 92 if (!mem) { 93 dev_err(&pdev->dev, "no mem resource?\n"); 94 return -EINVAL; 95 } 96 97 irq = platform_get_irq(pdev, 0); 98 if (irq < 0) { 99 dev_err(&pdev->dev, "no irq resource?\n"); 100 return irq; /* -ENXIO */ 101 } 102 103 dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); 104 if (!dev) 105 return -ENOMEM; 106 107 dev->base = devm_ioremap_resource(&pdev->dev, mem); 108 if (IS_ERR(dev->base)) 109 return PTR_ERR(dev->base); 110 111 init_completion(&dev->cmd_complete); 112 mutex_init(&dev->lock); 113 dev->dev = &pdev->dev; 114 dev->irq = irq; 115 platform_set_drvdata(pdev, dev); 116 117 dev->clk = devm_clk_get(&pdev->dev, NULL); 118 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; 119 120 if (IS_ERR(dev->clk)) 121 return PTR_ERR(dev->clk); 122 clk_prepare_enable(dev->clk); 123 124 dev->functionality = 125 I2C_FUNC_I2C | 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; 133 134 /* Try first if we can configure the device from ACPI */ 135 r = dw_i2c_acpi_configure(pdev); 136 if (r) { 137 u32 param1 = i2c_dw_read_comp_param(dev); 138 139 dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; 140 dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1; 141 dev->adapter.nr = pdev->id; 142 } 143 r = i2c_dw_init(dev); 144 if (r) 145 return r; 146 147 i2c_dw_disable_int(dev); 148 r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED, 149 pdev->name, dev); 150 if (r) { 151 dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq); 152 return r; 153 } 154 155 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", 160 sizeof(adap->name)); 161 adap->algo = &i2c_dw_algo; 162 adap->dev.parent = &pdev->dev; 163 adap->dev.of_node = pdev->dev.of_node; 164 165 r = i2c_add_numbered_adapter(adap); 166 if (r) { 167 dev_err(&pdev->dev, "failure adding adapter\n"); 168 return r; 169 } 170 of_i2c_register_devices(adap); 171 acpi_i2c_register_devices(adap); 172 173 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); 177 178 return 0; 179 } 180 181 static int dw_i2c_remove(struct platform_device *pdev) 182 { 183 struct dw_i2c_dev *dev = platform_get_drvdata(pdev); 184 185 pm_runtime_get_sync(&pdev->dev); 186 187 i2c_del_adapter(&dev->adapter); 188 189 i2c_dw_disable(dev); 190 191 pm_runtime_put(&pdev->dev); 192 pm_runtime_disable(&pdev->dev); 193 194 return 0; 195 } 196 197 #ifdef CONFIG_OF 198 static const struct of_device_id dw_i2c_of_match[] = { 199 { .compatible = "snps,designware-i2c", }, 200 {}, 201 }; 202 MODULE_DEVICE_TABLE(of, dw_i2c_of_match); 203 #endif 204 205 #ifdef CONFIG_PM 206 static int dw_i2c_suspend(struct device *dev) 207 { 208 struct platform_device *pdev = to_platform_device(dev); 209 struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev); 210 211 clk_disable_unprepare(i_dev->clk); 212 213 return 0; 214 } 215 216 static int dw_i2c_resume(struct device *dev) 217 { 218 struct platform_device *pdev = to_platform_device(dev); 219 struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev); 220 221 clk_prepare_enable(i_dev->clk); 222 i2c_dw_init(i_dev); 223 224 return 0; 225 } 226 #endif 227 228 static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume); 229 230 /* work with hotplug and coldplug */ 231 MODULE_ALIAS("platform:i2c_designware"); 232 233 static struct platform_driver dw_i2c_driver = { 234 .remove = dw_i2c_remove, 235 .driver = { 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, 241 }, 242 }; 243 244 static int __init dw_i2c_init_driver(void) 245 { 246 return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe); 247 } 248 subsys_initcall(dw_i2c_init_driver); 249 250 static void __exit dw_i2c_exit_driver(void) 251 { 252 platform_driver_unregister(&dw_i2c_driver); 253 } 254 module_exit(dw_i2c_exit_driver); 255 256 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); 257 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); 258 MODULE_LICENSE("GPL"); 259