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
  89         dev->tx_fifo_depth = 32;
  90         dev->rx_fifo_depth = 32;
  91
  92         /*
  93          * Try to get SDA hold time and *CNT values from an ACPI method for
  94          * selected speed modes.
  95          */
  96         dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht);
  97         dw_i2c_acpi_params(pdev, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht);
  98         dw_i2c_acpi_params(pdev, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht);
  99         dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht);
 100
 101         switch (t->bus_freq_hz) {
 102         case I2C_MAX_STANDARD_MODE_FREQ:
 103                 dev->sda_hold_time = ss_ht;
 104                 break;
 105         case I2C_MAX_FAST_MODE_PLUS_FREQ:
 106                 dev->sda_hold_time = fp_ht;
 107                 break;
 108         case I2C_MAX_HIGH_SPEED_MODE_FREQ:
 109                 dev->sda_hold_time = hs_ht;
 110                 break;
 111         case I2C_MAX_FAST_MODE_FREQ:
 112         default:
 113                 dev->sda_hold_time = fs_ht;
 114                 break;
 115         }
 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", ACCESS_NO_IRQ_SUSPEND },
 126         { "808622C1", ACCESS_NO_IRQ_SUSPEND | MODEL_CHERRYTRAIL },
 127         { "AMD0010", ACCESS_INTR_MASK },
 128         { "AMDI0010", ACCESS_INTR_MASK },
 129         { "AMDI0510", 0 },
 130         { "APMC0D0F", 0 },
 131         { "HISI02A1", 0 },
 132         { "HISI02A2", 0 },
 133         { "HISI02A3", 0 },
 134         { }
 135 };
 136 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
 137 #else
 138 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
 139 {
 140         return -ENODEV;
 141 }
 142 #endif
 143
 144 #ifdef CONFIG_OF
 145 #define MSCC_ICPU_CFG_TWI_DELAY         0x0
 146 #define MSCC_ICPU_CFG_TWI_DELAY_ENABLE  BIT(0)
 147 #define MSCC_ICPU_CFG_TWI_SPIKE_FILTER  0x4
 148
 149 static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev)
 150 {
 151         writel((dev->sda_hold_time << 1) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE,
 152                dev->ext + MSCC_ICPU_CFG_TWI_DELAY);
 153
 154         return 0;
 155 }
 156
 157 static int dw_i2c_of_configure(struct platform_device *pdev)
 158 {
 159         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 160         struct resource *mem;
 161
 162         switch (dev->flags & MODEL_MASK) {
 163         case MODEL_MSCC_OCELOT:
 164                 mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 165                 dev->ext = devm_ioremap_resource(&pdev->dev, mem);
 166                 if (!IS_ERR(dev->ext))
 167                         dev->set_sda_hold_time = mscc_twi_set_sda_hold_time;
 168                 break;
 169         default:
 170                 break;
 171         }
 172
 173         return 0;
 174 }
 175
 176 static const struct of_device_id dw_i2c_of_match[] = {
 177         { .compatible = "snps,designware-i2c", },
 178         { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
 179         {},
 180 };
 181 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
 182 #else
 183 static inline int dw_i2c_of_configure(struct platform_device *pdev)
 184 {
 185         return -ENODEV;
 186 }
 187 #endif
 188
 189 static void i2c_dw_configure_master(struct dw_i2c_dev *dev)
 190 {
 191         struct i2c_timings *t = &dev->timings;
 192
 193         dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY;
 194
 195         dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
 196                           DW_IC_CON_RESTART_EN;
 197
 198         dev->mode = DW_IC_MASTER;
 199
 200         switch (t->bus_freq_hz) {
 201         case I2C_MAX_STANDARD_MODE_FREQ:
 202                 dev->master_cfg |= DW_IC_CON_SPEED_STD;
 203                 break;
 204         case I2C_MAX_HIGH_SPEED_MODE_FREQ:
 205                 dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
 206                 break;
 207         default:
 208                 dev->master_cfg |= DW_IC_CON_SPEED_FAST;
 209         }
 210 }
 211
 212 static void i2c_dw_configure_slave(struct dw_i2c_dev *dev)
 213 {
 214         dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY;
 215
 216         dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL |
 217                          DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED;
 218
 219         dev->mode = DW_IC_SLAVE;
 220 }
 221
 222 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
 223 {
 224         pm_runtime_disable(dev->dev);
 225
 226         if (dev->shared_with_punit)
 227                 pm_runtime_put_noidle(dev->dev);
 228 }
 229
 230 static const u32 supported_speeds[] = {
 231         I2C_MAX_HIGH_SPEED_MODE_FREQ,
 232         I2C_MAX_FAST_MODE_PLUS_FREQ,
 233         I2C_MAX_FAST_MODE_FREQ,
 234         I2C_MAX_STANDARD_MODE_FREQ,
 235 };
 236
 237 static int dw_i2c_plat_probe(struct platform_device *pdev)
 238 {
 239         struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
 240         struct i2c_adapter *adap;
 241         struct dw_i2c_dev *dev;
 242         struct i2c_timings *t;
 243         u32 acpi_speed;
 244         struct resource *mem;
 245         int i, irq, ret;
 246
 247         irq = platform_get_irq(pdev, 0);
 248         if (irq < 0)
 249                 return irq;
 250
 251         dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
 252         if (!dev)
 253                 return -ENOMEM;
 254
 255         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 256         dev->base = devm_ioremap_resource(&pdev->dev, mem);
 257         if (IS_ERR(dev->base))
 258                 return PTR_ERR(dev->base);
 259
 260         dev->dev = &pdev->dev;
 261         dev->irq = irq;
 262         platform_set_drvdata(pdev, dev);
 263
 264         dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
 265         if (IS_ERR(dev->rst))
 266                 return PTR_ERR(dev->rst);
 267
 268         reset_control_deassert(dev->rst);
 269
 270         t = &dev->timings;
 271         if (pdata)
 272                 t->bus_freq_hz = pdata->i2c_scl_freq;
 273         else
 274                 i2c_parse_fw_timings(&pdev->dev, t, false);
 275
 276         acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
 277         /*
 278          * Some DSTDs use a non standard speed, round down to the lowest
 279          * standard speed.
 280          */
 281         for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) {
 282                 if (acpi_speed >= supported_speeds[i])
 283                         break;
 284         }
 285         acpi_speed = i < ARRAY_SIZE(supported_speeds) ? supported_speeds[i] : 0;
 286
 287         /*
 288          * Find bus speed from the "clock-frequency" device property, ACPI
 289          * or by using fast mode if neither is set.
 290          */
 291         if (acpi_speed && t->bus_freq_hz)
 292                 t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
 293         else if (acpi_speed || t->bus_freq_hz)
 294                 t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
 295         else
 296                 t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
 297
 298         dev->flags |= (uintptr_t)device_get_match_data(&pdev->dev);
 299
 300         if (pdev->dev.of_node)
 301                 dw_i2c_of_configure(pdev);
 302
 303         if (has_acpi_companion(&pdev->dev))
 304                 dw_i2c_acpi_configure(pdev);
 305
 306         /*
 307          * Only standard mode at 100kHz, fast mode at 400kHz,
 308          * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
 309          */
 310         for (i = 0; i < ARRAY_SIZE(supported_speeds); i++) {
 311                 if (t->bus_freq_hz == supported_speeds[i])
 312                         break;
 313         }
 314         if (i == ARRAY_SIZE(supported_speeds)) {
 315                 dev_err(&pdev->dev,
 316                         "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
 317                         t->bus_freq_hz);
 318                 ret = -EINVAL;
 319                 goto exit_reset;
 320         }
 321
 322         ret = i2c_dw_probe_lock_support(dev);
 323         if (ret)
 324                 goto exit_reset;
 325
 326         if (i2c_detect_slave_mode(&pdev->dev))
 327                 i2c_dw_configure_slave(dev);
 328         else
 329                 i2c_dw_configure_master(dev);
 330
 331         /* Optional interface clock */
 332         dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
 333         if (IS_ERR(dev->pclk)) {
 334                 ret = PTR_ERR(dev->pclk);
 335                 goto exit_reset;
 336         }
 337
 338         dev->clk = devm_clk_get(&pdev->dev, NULL);
 339         if (!i2c_dw_prepare_clk(dev, true)) {
 340                 u64 clk_khz;
 341
 342                 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
 343                 clk_khz = dev->get_clk_rate_khz(dev);
 344
 345                 if (!dev->sda_hold_time && t->sda_hold_ns)
 346                         dev->sda_hold_time =
 347                                 div_u64(clk_khz * t->sda_hold_ns + 500000, 1000000);
 348         }
 349
 350         adap = &dev->adapter;
 351         adap->owner = THIS_MODULE;
 352         adap->class = I2C_CLASS_DEPRECATED;
 353         ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 354         adap->dev.of_node = pdev->dev.of_node;
 355         adap->nr = -1;
 356
 357         if (dev->flags & ACCESS_NO_IRQ_SUSPEND) {
 358                 dev_pm_set_driver_flags(&pdev->dev,
 359                                         DPM_FLAG_SMART_PREPARE |
 360                                         DPM_FLAG_LEAVE_SUSPENDED);
 361         } else {
 362                 dev_pm_set_driver_flags(&pdev->dev,
 363                                         DPM_FLAG_SMART_PREPARE |
 364                                         DPM_FLAG_SMART_SUSPEND |
 365                                         DPM_FLAG_LEAVE_SUSPENDED);
 366         }
 367
 368         /* The code below assumes runtime PM to be disabled. */
 369         WARN_ON(pm_runtime_enabled(&pdev->dev));
 370
 371         pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 372         pm_runtime_use_autosuspend(&pdev->dev);
 373         pm_runtime_set_active(&pdev->dev);
 374
 375         if (dev->shared_with_punit)
 376                 pm_runtime_get_noresume(&pdev->dev);
 377
 378         pm_runtime_enable(&pdev->dev);
 379
 380         if (dev->mode == DW_IC_SLAVE)
 381                 ret = i2c_dw_probe_slave(dev);
 382         else
 383                 ret = i2c_dw_probe(dev);
 384
 385         if (ret)
 386                 goto exit_probe;
 387
 388         return ret;
 389
 390 exit_probe:
 391         dw_i2c_plat_pm_cleanup(dev);
 392 exit_reset:
 393         reset_control_assert(dev->rst);
 394         return ret;
 395 }
 396
 397 static int dw_i2c_plat_remove(struct platform_device *pdev)
 398 {
 399         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 400
 401         pm_runtime_get_sync(&pdev->dev);
 402
 403         i2c_del_adapter(&dev->adapter);
 404
 405         dev->disable(dev);
 406
 407         pm_runtime_dont_use_autosuspend(&pdev->dev);
 408         pm_runtime_put_sync(&pdev->dev);
 409         dw_i2c_plat_pm_cleanup(dev);
 410
 411         reset_control_assert(dev->rst);
 412
 413         return 0;
 414 }
 415
 416 #ifdef CONFIG_PM_SLEEP
 417 static int dw_i2c_plat_prepare(struct device *dev)
 418 {
 419         /*
 420          * If the ACPI companion device object is present for this device, it
 421          * may be accessed during suspend and resume of other devices via I2C
 422          * operation regions, so tell the PM core and middle layers to avoid
 423          * skipping system suspend/resume callbacks for it in that case.
 424          */
 425         return !has_acpi_companion(dev);
 426 }
 427
 428 static void dw_i2c_plat_complete(struct device *dev)
 429 {
 430         /*
 431          * The device can only be in runtime suspend at this point if it has not
 432          * been resumed throughout the ending system suspend/resume cycle, so if
 433          * the platform firmware might mess up with it, request the runtime PM
 434          * framework to resume it.
 435          */
 436         if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
 437                 pm_request_resume(dev);
 438 }
 439 #else
 440 #define dw_i2c_plat_prepare     NULL
 441 #define dw_i2c_plat_complete    NULL
 442 #endif
 443
 444 #ifdef CONFIG_PM
 445 static int dw_i2c_plat_suspend(struct device *dev)
 446 {
 447         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 448
 449         i_dev->suspended = true;
 450
 451         if (i_dev->shared_with_punit)
 452                 return 0;
 453
 454         i_dev->disable(i_dev);
 455         i2c_dw_prepare_clk(i_dev, false);
 456
 457         return 0;
 458 }
 459
 460 static int dw_i2c_plat_resume(struct device *dev)
 461 {
 462         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 463
 464         if (!i_dev->shared_with_punit)
 465                 i2c_dw_prepare_clk(i_dev, true);
 466
 467         i_dev->init(i_dev);
 468         i_dev->suspended = false;
 469
 470         return 0;
 471 }
 472
 473 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 474         .prepare = dw_i2c_plat_prepare,
 475         .complete = dw_i2c_plat_complete,
 476         SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
 477         SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
 478 };
 479
 480 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
 481 #else
 482 #define DW_I2C_DEV_PMOPS NULL
 483 #endif
 484
 485 /* Work with hotplug and coldplug */
 486 MODULE_ALIAS("platform:i2c_designware");
 487
 488 static struct platform_driver dw_i2c_driver = {
 489         .probe = dw_i2c_plat_probe,
 490         .remove = dw_i2c_plat_remove,
 491         .driver         = {
 492                 .name   = "i2c_designware",
 493                 .of_match_table = of_match_ptr(dw_i2c_of_match),
 494                 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 495                 .pm     = DW_I2C_DEV_PMOPS,
 496         },
 497 };
 498
 499 static int __init dw_i2c_init_driver(void)
 500 {
 501         return platform_driver_register(&dw_i2c_driver);
 502 }
 503 subsys_initcall(dw_i2c_init_driver);
 504
 505 static void __exit dw_i2c_exit_driver(void)
 506 {
 507         platform_driver_unregister(&dw_i2c_driver);
 508 }
 509 module_exit(dw_i2c_exit_driver);
 510
 511 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 512 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
 513 MODULE_LICENSE("GPL");