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

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Synopsys DesignWare I2C adapter driver.
   4  *
   5  * Based on the TI DAVINCI I2C adapter driver.
   6  *
   7  * Copyright (C) 2006 Texas Instruments.
   8  * Copyright (C) 2007 MontaVista Software Inc.
   9  * Copyright (C) 2009 Provigent Ltd.
  10  */
  11 #include <linux/acpi.h>
  12 #include <linux/clk-provider.h>
  13 #include <linux/clk.h>
  14 #include <linux/delay.h>
  15 #include <linux/dmi.h>
  16 #include <linux/err.h>
  17 #include <linux/errno.h>
  18 #include <linux/i2c.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/io.h>
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/of.h>
  24 #include <linux/platform_data/i2c-designware.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/pm.h>
  27 #include <linux/pm_runtime.h>
  28 #include <linux/property.h>
  29 #include <linux/reset.h>
  30 #include <linux/sched.h>
  31 #include <linux/slab.h>
  32 #include <linux/suspend.h>
  33
  34 #include "i2c-designware-core.h"
  35
  36 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
  37 {
  38         return clk_get_rate(dev->clk)/1000;
  39 }
  40
  41 #ifdef CONFIG_ACPI
  42 /*
  43  * The HCNT/LCNT information coming from ACPI should be the most accurate
  44  * for given platform. However, some systems get it wrong. On such systems
  45  * we get better results by calculating those based on the input clock.
  46  */
  47 static const struct dmi_system_id dw_i2c_no_acpi_params[] = {
  48         {
  49                 .ident = "Dell Inspiron 7348",
  50                 .matches = {
  51                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
  52                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"),
  53                 },
  54         },
  55         { }
  56 };
  57
  58 static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
  59                                u16 *hcnt, u16 *lcnt, u32 *sda_hold)
  60 {
  61         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
  62         acpi_handle handle = ACPI_HANDLE(&pdev->dev);
  63         union acpi_object *obj;
  64
  65         if (dmi_check_system(dw_i2c_no_acpi_params))
  66                 return;
  67
  68         if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
  69                 return;
  70
  71         obj = (union acpi_object *)buf.pointer;
  72         if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) {
  73                 const union acpi_object *objs = obj->package.elements;
  74
  75                 *hcnt = (u16)objs[0].integer.value;
  76                 *lcnt = (u16)objs[1].integer.value;
  77                 *sda_hold = (u32)objs[2].integer.value;
  78         }
  79
  80         kfree(buf.pointer);
  81 }
  82
  83 static int dw_i2c_acpi_configure(struct platform_device *pdev)
  84 {
  85         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
  86         struct i2c_timings *t = &dev->timings;
  87         u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0;
  88         acpi_handle handle = ACPI_HANDLE(&pdev->dev);
  89         const struct acpi_device_id *id;
  90         struct acpi_device *adev;
  91         const char *uid;
  92
  93         dev->adapter.nr = -1;
  94         dev->tx_fifo_depth = 32;
  95         dev->rx_fifo_depth = 32;
  96
  97         /*
  98          * Try to get SDA hold time and *CNT values from an ACPI method for
  99          * selected speed modes.
 100          */
 101         dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht);
 102         dw_i2c_acpi_params(pdev, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht);
 103         dw_i2c_acpi_params(pdev, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht);
 104         dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht);
 105
 106         switch (t->bus_freq_hz) {
 107         case 100000:
 108                 dev->sda_hold_time = ss_ht;
 109                 break;
 110         case 1000000:
 111                 dev->sda_hold_time = fp_ht;
 112                 break;
 113         case 3400000:
 114                 dev->sda_hold_time = hs_ht;
 115                 break;
 116         case 400000:
 117         default:
 118                 dev->sda_hold_time = fs_ht;
 119                 break;
 120         }
 121
 122         id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
 123         if (id && id->driver_data)
 124                 dev->flags |= (u32)id->driver_data;
 125
 126         if (acpi_bus_get_device(handle, &adev))
 127                 return -ENODEV;
 128
 129         /*
 130          * Cherrytrail I2C7 gets used for the PMIC which gets accessed
 131          * through ACPI opregions during late suspend / early resume
 132          * disable pm for it.
 133          */
 134         uid = adev->pnp.unique_id;
 135         if ((dev->flags & MODEL_CHERRYTRAIL) && !strcmp(uid, "7"))
 136                 dev->pm_disabled = true;
 137
 138         return 0;
 139 }
 140
 141 static const struct acpi_device_id dw_i2c_acpi_match[] = {
 142         { "INT33C2", 0 },
 143         { "INT33C3", 0 },
 144         { "INT3432", 0 },
 145         { "INT3433", 0 },
 146         { "80860F41", 0 },
 147         { "808622C1", MODEL_CHERRYTRAIL },
 148         { "AMD0010", ACCESS_INTR_MASK },
 149         { "AMDI0010", ACCESS_INTR_MASK },
 150         { "AMDI0510", 0 },
 151         { "APMC0D0F", 0 },
 152         { "HISI02A1", 0 },
 153         { "HISI02A2", 0 },
 154         { }
 155 };
 156 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
 157 #else
 158 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
 159 {
 160         return -ENODEV;
 161 }
 162 #endif
 163
 164 static void i2c_dw_configure_master(struct dw_i2c_dev *dev)
 165 {
 166         struct i2c_timings *t = &dev->timings;
 167
 168         dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY;
 169
 170         dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
 171                           DW_IC_CON_RESTART_EN;
 172
 173         dev->mode = DW_IC_MASTER;
 174
 175         switch (t->bus_freq_hz) {
 176         case 100000:
 177                 dev->master_cfg |= DW_IC_CON_SPEED_STD;
 178                 break;
 179         case 3400000:
 180                 dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
 181                 break;
 182         default:
 183                 dev->master_cfg |= DW_IC_CON_SPEED_FAST;
 184         }
 185 }
 186
 187 static void i2c_dw_configure_slave(struct dw_i2c_dev *dev)
 188 {
 189         dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY;
 190
 191         dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL |
 192                          DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED;
 193
 194         dev->mode = DW_IC_SLAVE;
 195 }
 196
 197 static void dw_i2c_set_fifo_size(struct dw_i2c_dev *dev, int id)
 198 {
 199         u32 param, tx_fifo_depth, rx_fifo_depth;
 200
 201         /*
 202          * Try to detect the FIFO depth if not set by interface driver,
 203          * the depth could be from 2 to 256 from HW spec.
 204          */
 205         param = i2c_dw_read_comp_param(dev);
 206         tx_fifo_depth = ((param >> 16) & 0xff) + 1;
 207         rx_fifo_depth = ((param >> 8)  & 0xff) + 1;
 208         if (!dev->tx_fifo_depth) {
 209                 dev->tx_fifo_depth = tx_fifo_depth;
 210                 dev->rx_fifo_depth = rx_fifo_depth;
 211                 dev->adapter.nr = id;
 212         } else if (tx_fifo_depth >= 2) {
 213                 dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
 214                                 tx_fifo_depth);
 215                 dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
 216                                 rx_fifo_depth);
 217         }
 218 }
 219
 220 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
 221 {
 222         pm_runtime_disable(dev->dev);
 223
 224         if (dev->pm_disabled)
 225                 pm_runtime_put_noidle(dev->dev);
 226 }
 227
 228 static int dw_i2c_plat_probe(struct platform_device *pdev)
 229 {
 230         struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
 231         struct i2c_adapter *adap;
 232         struct dw_i2c_dev *dev;
 233         struct i2c_timings *t;
 234         u32 acpi_speed;
 235         struct resource *mem;
 236         int i, irq, ret;
 237         static const int supported_speeds[] = {
 238                 0, 100000, 400000, 1000000, 3400000
 239         };
 240
 241         irq = platform_get_irq(pdev, 0);
 242         if (irq < 0)
 243                 return irq;
 244
 245         dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
 246         if (!dev)
 247                 return -ENOMEM;
 248
 249         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 250         dev->base = devm_ioremap_resource(&pdev->dev, mem);
 251         if (IS_ERR(dev->base))
 252                 return PTR_ERR(dev->base);
 253
 254         dev->dev = &pdev->dev;
 255         dev->irq = irq;
 256         platform_set_drvdata(pdev, dev);
 257
 258         dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
 259         if (IS_ERR(dev->rst)) {
 260                 if (PTR_ERR(dev->rst) == -EPROBE_DEFER)
 261                         return -EPROBE_DEFER;
 262         } else {
 263                 reset_control_deassert(dev->rst);
 264         }
 265
 266         t = &dev->timings;
 267         if (pdata)
 268                 t->bus_freq_hz = pdata->i2c_scl_freq;
 269         else
 270                 i2c_parse_fw_timings(&pdev->dev, t, false);
 271
 272         acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
 273         /*
 274          * Some DSTDs use a non standard speed, round down to the lowest
 275          * standard speed.
 276          */
 277         for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) {
 278                 if (acpi_speed < supported_speeds[i])
 279                         break;
 280         }
 281         acpi_speed = supported_speeds[i - 1];
 282
 283         /*
 284          * Find bus speed from the "clock-frequency" device property, ACPI
 285          * or by using fast mode if neither is set.
 286          */
 287         if (acpi_speed && t->bus_freq_hz)
 288                 t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
 289         else if (acpi_speed || t->bus_freq_hz)
 290                 t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
 291         else
 292                 t->bus_freq_hz = 400000;
 293
 294         if (has_acpi_companion(&pdev->dev))
 295                 dw_i2c_acpi_configure(pdev);
 296
 297         /*
 298          * Only standard mode at 100kHz, fast mode at 400kHz,
 299          * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
 300          */
 301         if (t->bus_freq_hz != 100000 && t->bus_freq_hz != 400000 &&
 302             t->bus_freq_hz != 1000000 && t->bus_freq_hz != 3400000) {
 303                 dev_err(&pdev->dev,
 304                         "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
 305                         t->bus_freq_hz);
 306                 ret = -EINVAL;
 307                 goto exit_reset;
 308         }
 309
 310         ret = i2c_dw_probe_lock_support(dev);
 311         if (ret)
 312                 goto exit_reset;
 313
 314         if (i2c_detect_slave_mode(&pdev->dev))
 315                 i2c_dw_configure_slave(dev);
 316         else
 317                 i2c_dw_configure_master(dev);
 318
 319         dev->clk = devm_clk_get(&pdev->dev, NULL);
 320         if (!i2c_dw_prepare_clk(dev, true)) {
 321                 u64 clk_khz;
 322
 323                 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
 324                 clk_khz = dev->get_clk_rate_khz(dev);
 325
 326                 if (!dev->sda_hold_time && t->sda_hold_ns)
 327                         dev->sda_hold_time =
 328                                 div_u64(clk_khz * t->sda_hold_ns + 500000, 1000000);
 329         }
 330
 331         dw_i2c_set_fifo_size(dev, pdev->id);
 332
 333         adap = &dev->adapter;
 334         adap->owner = THIS_MODULE;
 335         adap->class = I2C_CLASS_DEPRECATED;
 336         ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 337         adap->dev.of_node = pdev->dev.of_node;
 338
 339         dev_pm_set_driver_flags(&pdev->dev,
 340                                 DPM_FLAG_SMART_PREPARE |
 341                                 DPM_FLAG_SMART_SUSPEND |
 342                                 DPM_FLAG_LEAVE_SUSPENDED);
 343
 344         /* The code below assumes runtime PM to be disabled. */
 345         WARN_ON(pm_runtime_enabled(&pdev->dev));
 346
 347         pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 348         pm_runtime_use_autosuspend(&pdev->dev);
 349         pm_runtime_set_active(&pdev->dev);
 350
 351         if (dev->pm_disabled)
 352                 pm_runtime_get_noresume(&pdev->dev);
 353
 354         pm_runtime_enable(&pdev->dev);
 355
 356         if (dev->mode == DW_IC_SLAVE)
 357                 ret = i2c_dw_probe_slave(dev);
 358         else
 359                 ret = i2c_dw_probe(dev);
 360
 361         if (ret)
 362                 goto exit_probe;
 363
 364         return ret;
 365
 366 exit_probe:
 367         dw_i2c_plat_pm_cleanup(dev);
 368 exit_reset:
 369         if (!IS_ERR_OR_NULL(dev->rst))
 370                 reset_control_assert(dev->rst);
 371         return ret;
 372 }
 373
 374 static int dw_i2c_plat_remove(struct platform_device *pdev)
 375 {
 376         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 377
 378         pm_runtime_get_sync(&pdev->dev);
 379
 380         i2c_del_adapter(&dev->adapter);
 381
 382         dev->disable(dev);
 383
 384         pm_runtime_dont_use_autosuspend(&pdev->dev);
 385         pm_runtime_put_sync(&pdev->dev);
 386         dw_i2c_plat_pm_cleanup(dev);
 387
 388         if (!IS_ERR_OR_NULL(dev->rst))
 389                 reset_control_assert(dev->rst);
 390
 391         i2c_dw_remove_lock_support(dev);
 392
 393         return 0;
 394 }
 395
 396 #ifdef CONFIG_OF
 397 static const struct of_device_id dw_i2c_of_match[] = {
 398         { .compatible = "snps,designware-i2c", },
 399         {},
 400 };
 401 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
 402 #endif
 403
 404 #ifdef CONFIG_PM_SLEEP
 405 static int dw_i2c_plat_prepare(struct device *dev)
 406 {
 407         /*
 408          * If the ACPI companion device object is present for this device, it
 409          * may be accessed during suspend and resume of other devices via I2C
 410          * operation regions, so tell the PM core and middle layers to avoid
 411          * skipping system suspend/resume callbacks for it in that case.
 412          */
 413         return !has_acpi_companion(dev);
 414 }
 415
 416 static void dw_i2c_plat_complete(struct device *dev)
 417 {
 418         /*
 419          * The device can only be in runtime suspend at this point if it has not
 420          * been resumed throughout the ending system suspend/resume cycle, so if
 421          * the platform firmware might mess up with it, request the runtime PM
 422          * framework to resume it.
 423          */
 424         if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
 425                 pm_request_resume(dev);
 426 }
 427 #else
 428 #define dw_i2c_plat_prepare     NULL
 429 #define dw_i2c_plat_complete    NULL
 430 #endif
 431
 432 #ifdef CONFIG_PM
 433 static int dw_i2c_plat_suspend(struct device *dev)
 434 {
 435         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 436
 437         if (i_dev->pm_disabled)
 438                 return 0;
 439
 440         i_dev->disable(i_dev);
 441         i2c_dw_prepare_clk(i_dev, false);
 442
 443         return 0;
 444 }
 445
 446 static int dw_i2c_plat_resume(struct device *dev)
 447 {
 448         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 449
 450         if (!i_dev->pm_disabled)
 451                 i2c_dw_prepare_clk(i_dev, true);
 452
 453         i_dev->init(i_dev);
 454
 455         return 0;
 456 }
 457
 458 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 459         .prepare = dw_i2c_plat_prepare,
 460         .complete = dw_i2c_plat_complete,
 461         SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
 462         SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
 463 };
 464
 465 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
 466 #else
 467 #define DW_I2C_DEV_PMOPS NULL
 468 #endif
 469
 470 /* Work with hotplug and coldplug */
 471 MODULE_ALIAS("platform:i2c_designware");
 472
 473 static struct platform_driver dw_i2c_driver = {
 474         .probe = dw_i2c_plat_probe,
 475         .remove = dw_i2c_plat_remove,
 476         .driver         = {
 477                 .name   = "i2c_designware",
 478                 .of_match_table = of_match_ptr(dw_i2c_of_match),
 479                 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 480                 .pm     = DW_I2C_DEV_PMOPS,
 481         },
 482 };
 483
 484 static int __init dw_i2c_init_driver(void)
 485 {
 486         return platform_driver_register(&dw_i2c_driver);
 487 }
 488 subsys_initcall(dw_i2c_init_driver);
 489
 490 static void __exit dw_i2c_exit_driver(void)
 491 {
 492         platform_driver_unregister(&dw_i2c_driver);
 493 }
 494 module_exit(dw_i2c_exit_driver);
 495
 496 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 497 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
 498 MODULE_LICENSE("GPL");