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  *
  23  */
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/delay.h>
  27 #include <linux/dmi.h>
  28 #include <linux/i2c.h>
  29 #include <linux/clk.h>
  30 #include <linux/clk-provider.h>
  31 #include <linux/errno.h>
  32 #include <linux/sched.h>
  33 #include <linux/err.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/of.h>
  36 #include <linux/platform_device.h>
  37 #include <linux/pm.h>
  38 #include <linux/pm_runtime.h>
  39 #include <linux/property.h>
  40 #include <linux/io.h>
  41 #include <linux/slab.h>
  42 #include <linux/acpi.h>
  43 #include <linux/platform_data/i2c-designware.h>
  44 #include "i2c-designware-core.h"
  45
  46 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
  47 {
  48         return clk_get_rate(dev->clk)/1000;
  49 }
  50
  51 #ifdef CONFIG_ACPI
  52 /*
  53  * The HCNT/LCNT information coming from ACPI should be the most accurate
  54  * for given platform. However, some systems get it wrong. On such systems
  55  * we get better results by calculating those based on the input clock.
  56  */
  57 static const struct dmi_system_id dw_i2c_no_acpi_params[] = {
  58         {
  59                 .ident = "Dell Inspiron 7348",
  60                 .matches = {
  61                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
  62                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"),
  63                 },
  64         },
  65         { }
  66 };
  67
  68 static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
  69                                u16 *hcnt, u16 *lcnt, u32 *sda_hold)
  70 {
  71         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
  72         acpi_handle handle = ACPI_HANDLE(&pdev->dev);
  73         union acpi_object *obj;
  74
  75         if (dmi_check_system(dw_i2c_no_acpi_params))
  76                 return;
  77
  78         if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
  79                 return;
  80
  81         obj = (union acpi_object *)buf.pointer;
  82         if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) {
  83                 const union acpi_object *objs = obj->package.elements;
  84
  85                 *hcnt = (u16)objs[0].integer.value;
  86                 *lcnt = (u16)objs[1].integer.value;
  87                 if (sda_hold)
  88                         *sda_hold = (u32)objs[2].integer.value;
  89         }
  90
  91         kfree(buf.pointer);
  92 }
  93
  94 static int dw_i2c_acpi_configure(struct platform_device *pdev)
  95 {
  96         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
  97         const struct acpi_device_id *id;
  98
  99         dev->adapter.nr = -1;
 100         dev->tx_fifo_depth = 32;
 101         dev->rx_fifo_depth = 32;
 102
 103         /*
 104          * Try to get SDA hold time and *CNT values from an ACPI method if
 105          * it exists for both supported speed modes.
 106          */
 107         dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, NULL);
 108         dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt,
 109                            &dev->sda_hold_time);
 110         dw_i2c_acpi_params(pdev, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, NULL);
 111         dw_i2c_acpi_params(pdev, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, NULL);
 112
 113         id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
 114         if (id && id->driver_data)
 115                 dev->accessor_flags |= (u32)id->driver_data;
 116
 117         return 0;
 118 }
 119
 120 static const struct acpi_device_id dw_i2c_acpi_match[] = {
 121         { "INT33C2", 0 },
 122         { "INT33C3", 0 },
 123         { "INT3432", 0 },
 124         { "INT3433", 0 },
 125         { "80860F41", 0 },
 126         { "808622C1", 0 },
 127         { "AMD0010", ACCESS_INTR_MASK },
 128         { "AMDI0010", ACCESS_INTR_MASK },
 129         { "AMDI0510", 0 },
 130         { "APMC0D0F", 0 },
 131         { }
 132 };
 133 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
 134 #else
 135 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
 136 {
 137         return -ENODEV;
 138 }
 139 #endif
 140
 141 static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare)
 142 {
 143         if (IS_ERR(i_dev->clk))
 144                 return PTR_ERR(i_dev->clk);
 145
 146         if (prepare)
 147                 return clk_prepare_enable(i_dev->clk);
 148
 149         clk_disable_unprepare(i_dev->clk);
 150         return 0;
 151 }
 152
 153 static int dw_i2c_plat_probe(struct platform_device *pdev)
 154 {
 155         struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
 156         struct dw_i2c_dev *dev;
 157         struct i2c_adapter *adap;
 158         struct resource *mem;
 159         int irq, r;
 160         u32 acpi_speed, ht = 0;
 161
 162         irq = platform_get_irq(pdev, 0);
 163         if (irq < 0)
 164                 return irq;
 165
 166         dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
 167         if (!dev)
 168                 return -ENOMEM;
 169
 170         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 171         dev->base = devm_ioremap_resource(&pdev->dev, mem);
 172         if (IS_ERR(dev->base))
 173                 return PTR_ERR(dev->base);
 174
 175         dev->dev = &pdev->dev;
 176         dev->irq = irq;
 177         platform_set_drvdata(pdev, dev);
 178
 179         if (pdata) {
 180                 dev->clk_freq = pdata->i2c_scl_freq;
 181         } else {
 182                 device_property_read_u32(&pdev->dev, "i2c-sda-hold-time-ns",
 183                                          &ht);
 184                 device_property_read_u32(&pdev->dev, "i2c-sda-falling-time-ns",
 185                                          &dev->sda_falling_time);
 186                 device_property_read_u32(&pdev->dev, "i2c-scl-falling-time-ns",
 187                                          &dev->scl_falling_time);
 188                 device_property_read_u32(&pdev->dev, "clock-frequency",
 189                                          &dev->clk_freq);
 190         }
 191
 192         acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
 193         /*
 194          * Find bus speed from the "clock-frequency" device property, ACPI
 195          * or by using fast mode if neither is set.
 196          */
 197         if (acpi_speed && dev->clk_freq)
 198                 dev->clk_freq = min(dev->clk_freq, acpi_speed);
 199         else if (acpi_speed || dev->clk_freq)
 200                 dev->clk_freq = max(dev->clk_freq, acpi_speed);
 201         else
 202                 dev->clk_freq = 400000;
 203
 204         if (has_acpi_companion(&pdev->dev))
 205                 dw_i2c_acpi_configure(pdev);
 206
 207         /*
 208          * Only standard mode at 100kHz, fast mode at 400kHz,
 209          * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
 210          */
 211         if (dev->clk_freq != 100000 && dev->clk_freq != 400000
 212             && dev->clk_freq != 1000000 && dev->clk_freq != 3400000) {
 213                 dev_err(&pdev->dev,
 214                         "Only 100kHz, 400kHz, 1MHz and 3.4MHz supported");
 215                 return -EINVAL;
 216         }
 217
 218         r = i2c_dw_eval_lock_support(dev);
 219         if (r)
 220                 return r;
 221
 222         dev->functionality =
 223                 I2C_FUNC_I2C |
 224                 I2C_FUNC_10BIT_ADDR |
 225                 I2C_FUNC_SMBUS_BYTE |
 226                 I2C_FUNC_SMBUS_BYTE_DATA |
 227                 I2C_FUNC_SMBUS_WORD_DATA |
 228                 I2C_FUNC_SMBUS_BLOCK_DATA |
 229                 I2C_FUNC_SMBUS_I2C_BLOCK;
 230
 231         dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
 232                           DW_IC_CON_RESTART_EN;
 233
 234         switch (dev->clk_freq) {
 235         case 100000:
 236                 dev->master_cfg |= DW_IC_CON_SPEED_STD;
 237                 break;
 238         case 3400000:
 239                 dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
 240                 break;
 241         default:
 242                 dev->master_cfg |= DW_IC_CON_SPEED_FAST;
 243         }
 244
 245         dev->clk = devm_clk_get(&pdev->dev, NULL);
 246         if (!i2c_dw_plat_prepare_clk(dev, true)) {
 247                 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
 248
 249                 if (!dev->sda_hold_time && ht)
 250                         dev->sda_hold_time = div_u64(
 251                                 (u64)dev->get_clk_rate_khz(dev) * ht + 500000,
 252                                 1000000);
 253         }
 254
 255         if (!dev->tx_fifo_depth) {
 256                 u32 param1 = i2c_dw_read_comp_param(dev);
 257
 258                 dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
 259                 dev->rx_fifo_depth = ((param1 >> 8)  & 0xff) + 1;
 260                 dev->adapter.nr = pdev->id;
 261         }
 262
 263         adap = &dev->adapter;
 264         adap->owner = THIS_MODULE;
 265         adap->class = I2C_CLASS_DEPRECATED;
 266         ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 267         adap->dev.of_node = pdev->dev.of_node;
 268
 269         if (dev->pm_runtime_disabled) {
 270                 pm_runtime_forbid(&pdev->dev);
 271         } else {
 272                 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 273                 pm_runtime_use_autosuspend(&pdev->dev);
 274                 pm_runtime_set_active(&pdev->dev);
 275                 pm_runtime_enable(&pdev->dev);
 276         }
 277
 278         r = i2c_dw_probe(dev);
 279         if (r && !dev->pm_runtime_disabled)
 280                 pm_runtime_disable(&pdev->dev);
 281
 282         return r;
 283 }
 284
 285 static int dw_i2c_plat_remove(struct platform_device *pdev)
 286 {
 287         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 288
 289         pm_runtime_get_sync(&pdev->dev);
 290
 291         i2c_del_adapter(&dev->adapter);
 292
 293         i2c_dw_disable(dev);
 294
 295         pm_runtime_dont_use_autosuspend(&pdev->dev);
 296         pm_runtime_put_sync(&pdev->dev);
 297         if (!dev->pm_runtime_disabled)
 298                 pm_runtime_disable(&pdev->dev);
 299
 300         return 0;
 301 }
 302
 303 #ifdef CONFIG_OF
 304 static const struct of_device_id dw_i2c_of_match[] = {
 305         { .compatible = "snps,designware-i2c", },
 306         {},
 307 };
 308 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
 309 #endif
 310
 311 #ifdef CONFIG_PM_SLEEP
 312 static int dw_i2c_plat_prepare(struct device *dev)
 313 {
 314         return pm_runtime_suspended(dev);
 315 }
 316
 317 static void dw_i2c_plat_complete(struct device *dev)
 318 {
 319         if (dev->power.direct_complete)
 320                 pm_request_resume(dev);
 321 }
 322 #else
 323 #define dw_i2c_plat_prepare     NULL
 324 #define dw_i2c_plat_complete    NULL
 325 #endif
 326
 327 #ifdef CONFIG_PM
 328 static int dw_i2c_plat_suspend(struct device *dev)
 329 {
 330         struct platform_device *pdev = to_platform_device(dev);
 331         struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
 332
 333         i2c_dw_disable(i_dev);
 334         i2c_dw_plat_prepare_clk(i_dev, false);
 335
 336         return 0;
 337 }
 338
 339 static int dw_i2c_plat_resume(struct device *dev)
 340 {
 341         struct platform_device *pdev = to_platform_device(dev);
 342         struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
 343
 344         i2c_dw_plat_prepare_clk(i_dev, true);
 345
 346         if (!i_dev->pm_runtime_disabled)
 347                 i2c_dw_init(i_dev);
 348
 349         return 0;
 350 }
 351
 352 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 353         .prepare = dw_i2c_plat_prepare,
 354         .complete = dw_i2c_plat_complete,
 355         SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
 356         SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
 357 };
 358
 359 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
 360 #else
 361 #define DW_I2C_DEV_PMOPS NULL
 362 #endif
 363
 364 /* work with hotplug and coldplug */
 365 MODULE_ALIAS("platform:i2c_designware");
 366
 367 static struct platform_driver dw_i2c_driver = {
 368         .probe = dw_i2c_plat_probe,
 369         .remove = dw_i2c_plat_remove,
 370         .driver         = {
 371                 .name   = "i2c_designware",
 372                 .of_match_table = of_match_ptr(dw_i2c_of_match),
 373                 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 374                 .pm     = DW_I2C_DEV_PMOPS,
 375         },
 376 };
 377
 378 static int __init dw_i2c_init_driver(void)
 379 {
 380         return platform_driver_register(&dw_i2c_driver);
 381 }
 382 subsys_initcall(dw_i2c_init_driver);
 383
 384 static void __exit dw_i2c_exit_driver(void)
 385 {
 386         platform_driver_unregister(&dw_i2c_driver);
 387 }
 388 module_exit(dw_i2c_exit_driver);
 389
 390 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 391 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
 392 MODULE_LICENSE("GPL");