drivers/i2c/busses/i2c-designware-platdrv.c

   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         { }
  73 };
  74 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
  75 #else
  76 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
  77 {
  78         return -ENODEV;
  79 }
  80 #endif
  81
  82 static int dw_i2c_probe(struct platform_device *pdev)
  83 {
  84         struct dw_i2c_dev *dev;
  85         struct i2c_adapter *adap;
  86         struct resource *mem;
  87         int irq, r;
  88
  89         /* NOTE: driver uses the static register mapping */
  90         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  91         if (!mem) {
  92                 dev_err(&pdev->dev, "no mem resource?\n");
  93                 return -EINVAL;
  94         }
  95
  96         irq = platform_get_irq(pdev, 0);
  97         if (irq < 0) {
  98                 dev_err(&pdev->dev, "no irq resource?\n");
  99                 return irq; /* -ENXIO */
 100         }
 101
 102         dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
 103         if (!dev)
 104                 return -ENOMEM;
 105
 106         dev->base = devm_ioremap_resource(&pdev->dev, mem);
 107         if (IS_ERR(dev->base))
 108                 return PTR_ERR(dev->base);
 109
 110         init_completion(&dev->cmd_complete);
 111         mutex_init(&dev->lock);
 112         dev->dev = &pdev->dev;
 113         dev->irq = irq;
 114         platform_set_drvdata(pdev, dev);
 115
 116         dev->clk = devm_clk_get(&pdev->dev, NULL);
 117         dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
 118
 119         if (IS_ERR(dev->clk))
 120                 return PTR_ERR(dev->clk);
 121         clk_prepare_enable(dev->clk);
 122
 123         dev->functionality =
 124                 I2C_FUNC_I2C |
 125                 I2C_FUNC_10BIT_ADDR |
 126                 I2C_FUNC_SMBUS_BYTE |
 127                 I2C_FUNC_SMBUS_BYTE_DATA |
 128                 I2C_FUNC_SMBUS_WORD_DATA |
 129                 I2C_FUNC_SMBUS_I2C_BLOCK;
 130         dev->master_cfg =  DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
 131                 DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
 132
 133         /* Try first if we can configure the device from ACPI */
 134         r = dw_i2c_acpi_configure(pdev);
 135         if (r) {
 136                 u32 param1 = i2c_dw_read_comp_param(dev);
 137
 138                 dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
 139                 dev->rx_fifo_depth = ((param1 >> 8)  & 0xff) + 1;
 140                 dev->adapter.nr = pdev->id;
 141         }
 142         r = i2c_dw_init(dev);
 143         if (r)
 144                 return r;
 145
 146         i2c_dw_disable_int(dev);
 147         r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED,
 148                         pdev->name, dev);
 149         if (r) {
 150                 dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
 151                 return r;
 152         }
 153
 154         adap = &dev->adapter;
 155         i2c_set_adapdata(adap, dev);
 156         adap->owner = THIS_MODULE;
 157         adap->class = I2C_CLASS_HWMON;
 158         strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
 159                         sizeof(adap->name));
 160         adap->algo = &i2c_dw_algo;
 161         adap->dev.parent = &pdev->dev;
 162         adap->dev.of_node = pdev->dev.of_node;
 163
 164         r = i2c_add_numbered_adapter(adap);
 165         if (r) {
 166                 dev_err(&pdev->dev, "failure adding adapter\n");
 167                 return r;
 168         }
 169         of_i2c_register_devices(adap);
 170         acpi_i2c_register_devices(adap);
 171
 172         pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 173         pm_runtime_use_autosuspend(&pdev->dev);
 174         pm_runtime_set_active(&pdev->dev);
 175         pm_runtime_enable(&pdev->dev);
 176
 177         return 0;
 178 }
 179
 180 static int dw_i2c_remove(struct platform_device *pdev)
 181 {
 182         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 183
 184         pm_runtime_get_sync(&pdev->dev);
 185
 186         i2c_del_adapter(&dev->adapter);
 187
 188         i2c_dw_disable(dev);
 189
 190         pm_runtime_put(&pdev->dev);
 191         pm_runtime_disable(&pdev->dev);
 192
 193         return 0;
 194 }
 195
 196 #ifdef CONFIG_OF
 197 static const struct of_device_id dw_i2c_of_match[] = {
 198         { .compatible = "snps,designware-i2c", },
 199         {},
 200 };
 201 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
 202 #endif
 203
 204 #ifdef CONFIG_PM
 205 static int dw_i2c_suspend(struct device *dev)
 206 {
 207         struct platform_device *pdev = to_platform_device(dev);
 208         struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
 209
 210         clk_disable_unprepare(i_dev->clk);
 211
 212         return 0;
 213 }
 214
 215 static int dw_i2c_resume(struct device *dev)
 216 {
 217         struct platform_device *pdev = to_platform_device(dev);
 218         struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
 219
 220         clk_prepare_enable(i_dev->clk);
 221         i2c_dw_init(i_dev);
 222
 223         return 0;
 224 }
 225 #endif
 226
 227 static SIMPLE_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume);
 228
 229 /* work with hotplug and coldplug */
 230 MODULE_ALIAS("platform:i2c_designware");
 231
 232 static struct platform_driver dw_i2c_driver = {
 233         .remove         = dw_i2c_remove,
 234         .driver         = {
 235                 .name   = "i2c_designware",
 236                 .owner  = THIS_MODULE,
 237                 .of_match_table = of_match_ptr(dw_i2c_of_match),
 238                 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 239                 .pm     = &dw_i2c_dev_pm_ops,
 240         },
 241 };
 242
 243 static int __init dw_i2c_init_driver(void)
 244 {
 245         return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
 246 }
 247 subsys_initcall(dw_i2c_init_driver);
 248
 249 static void __exit dw_i2c_exit_driver(void)
 250 {
 251         platform_driver_unregister(&dw_i2c_driver);
 252 }
 253 module_exit(dw_i2c_exit_driver);
 254
 255 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 256 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
 257 MODULE_LICENSE("GPL");