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 100000:
 103                 dev->sda_hold_time = ss_ht;
 104                 break;
 105         case 1000000:
 106                 dev->sda_hold_time = fp_ht;
 107                 break;
 108         case 3400000:
 109                 dev->sda_hold_time = hs_ht;
 110                 break;
 111         case 400000:
 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 100000:
 202                 dev->master_cfg |= DW_IC_CON_SPEED_STD;
 203                 break;
 204         case 3400000:
 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_set_fifo_size(struct dw_i2c_dev *dev)
 223 {
 224         u32 param, tx_fifo_depth, rx_fifo_depth;
 225
 226         /*
 227          * Try to detect the FIFO depth if not set by interface driver,
 228          * the depth could be from 2 to 256 from HW spec.
 229          */
 230         param = i2c_dw_read_comp_param(dev);
 231         tx_fifo_depth = ((param >> 16) & 0xff) + 1;
 232         rx_fifo_depth = ((param >> 8)  & 0xff) + 1;
 233         if (!dev->tx_fifo_depth) {
 234                 dev->tx_fifo_depth = tx_fifo_depth;
 235                 dev->rx_fifo_depth = rx_fifo_depth;
 236         } else if (tx_fifo_depth >= 2) {
 237                 dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
 238                                 tx_fifo_depth);
 239                 dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
 240                                 rx_fifo_depth);
 241         }
 242 }
 243
 244 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
 245 {
 246         pm_runtime_disable(dev->dev);
 247
 248         if (dev->shared_with_punit)
 249                 pm_runtime_put_noidle(dev->dev);
 250 }
 251
 252 static int dw_i2c_plat_probe(struct platform_device *pdev)
 253 {
 254         struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
 255         struct i2c_adapter *adap;
 256         struct dw_i2c_dev *dev;
 257         struct i2c_timings *t;
 258         u32 acpi_speed;
 259         struct resource *mem;
 260         int i, irq, ret;
 261         static const int supported_speeds[] = {
 262                 0, 100000, 400000, 1000000, 3400000
 263         };
 264
 265         irq = platform_get_irq(pdev, 0);
 266         if (irq < 0)
 267                 return irq;
 268
 269         dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
 270         if (!dev)
 271                 return -ENOMEM;
 272
 273         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 274         dev->base = devm_ioremap_resource(&pdev->dev, mem);
 275         if (IS_ERR(dev->base))
 276                 return PTR_ERR(dev->base);
 277
 278         dev->dev = &pdev->dev;
 279         dev->irq = irq;
 280         platform_set_drvdata(pdev, dev);
 281
 282         dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
 283         if (IS_ERR(dev->rst))
 284                 return PTR_ERR(dev->rst);
 285
 286         reset_control_deassert(dev->rst);
 287
 288         t = &dev->timings;
 289         if (pdata)
 290                 t->bus_freq_hz = pdata->i2c_scl_freq;
 291         else
 292                 i2c_parse_fw_timings(&pdev->dev, t, false);
 293
 294         acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
 295         /*
 296          * Some DSTDs use a non standard speed, round down to the lowest
 297          * standard speed.
 298          */
 299         for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) {
 300                 if (acpi_speed < supported_speeds[i])
 301                         break;
 302         }
 303         acpi_speed = supported_speeds[i - 1];
 304
 305         /*
 306          * Find bus speed from the "clock-frequency" device property, ACPI
 307          * or by using fast mode if neither is set.
 308          */
 309         if (acpi_speed && t->bus_freq_hz)
 310                 t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
 311         else if (acpi_speed || t->bus_freq_hz)
 312                 t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
 313         else
 314                 t->bus_freq_hz = 400000;
 315
 316         dev->flags |= (uintptr_t)device_get_match_data(&pdev->dev);
 317
 318         if (pdev->dev.of_node)
 319                 dw_i2c_of_configure(pdev);
 320
 321         if (has_acpi_companion(&pdev->dev))
 322                 dw_i2c_acpi_configure(pdev);
 323
 324         /*
 325          * Only standard mode at 100kHz, fast mode at 400kHz,
 326          * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
 327          */
 328         if (t->bus_freq_hz != 100000 && t->bus_freq_hz != 400000 &&
 329             t->bus_freq_hz != 1000000 && t->bus_freq_hz != 3400000) {
 330                 dev_err(&pdev->dev,
 331                         "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
 332                         t->bus_freq_hz);
 333                 ret = -EINVAL;
 334                 goto exit_reset;
 335         }
 336
 337         ret = i2c_dw_probe_lock_support(dev);
 338         if (ret)
 339                 goto exit_reset;
 340
 341         if (i2c_detect_slave_mode(&pdev->dev))
 342                 i2c_dw_configure_slave(dev);
 343         else
 344                 i2c_dw_configure_master(dev);
 345
 346         /* Optional interface clock */
 347         dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
 348         if (IS_ERR(dev->pclk)) {
 349                 ret = PTR_ERR(dev->pclk);
 350                 goto exit_reset;
 351         }
 352
 353         dev->clk = devm_clk_get(&pdev->dev, NULL);
 354         if (!i2c_dw_prepare_clk(dev, true)) {
 355                 u64 clk_khz;
 356
 357                 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
 358                 clk_khz = dev->get_clk_rate_khz(dev);
 359
 360                 if (!dev->sda_hold_time && t->sda_hold_ns)
 361                         dev->sda_hold_time =
 362                                 div_u64(clk_khz * t->sda_hold_ns + 500000, 1000000);
 363         }
 364
 365         dw_i2c_set_fifo_size(dev);
 366
 367         adap = &dev->adapter;
 368         adap->owner = THIS_MODULE;
 369         adap->class = I2C_CLASS_DEPRECATED;
 370         ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 371         adap->dev.of_node = pdev->dev.of_node;
 372         adap->nr = -1;
 373
 374         dev_pm_set_driver_flags(&pdev->dev,
 375                                 DPM_FLAG_SMART_PREPARE |
 376                                 DPM_FLAG_SMART_SUSPEND |
 377                                 DPM_FLAG_LEAVE_SUSPENDED);
 378
 379         /* The code below assumes runtime PM to be disabled. */
 380         WARN_ON(pm_runtime_enabled(&pdev->dev));
 381
 382         pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 383         pm_runtime_use_autosuspend(&pdev->dev);
 384         pm_runtime_set_active(&pdev->dev);
 385
 386         if (dev->shared_with_punit)
 387                 pm_runtime_get_noresume(&pdev->dev);
 388
 389         pm_runtime_enable(&pdev->dev);
 390
 391         if (dev->mode == DW_IC_SLAVE)
 392                 ret = i2c_dw_probe_slave(dev);
 393         else
 394                 ret = i2c_dw_probe(dev);
 395
 396         if (ret)
 397                 goto exit_probe;
 398
 399         return ret;
 400
 401 exit_probe:
 402         dw_i2c_plat_pm_cleanup(dev);
 403 exit_reset:
 404         reset_control_assert(dev->rst);
 405         return ret;
 406 }
 407
 408 static int dw_i2c_plat_remove(struct platform_device *pdev)
 409 {
 410         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 411
 412         pm_runtime_get_sync(&pdev->dev);
 413
 414         i2c_del_adapter(&dev->adapter);
 415
 416         dev->disable(dev);
 417
 418         pm_runtime_dont_use_autosuspend(&pdev->dev);
 419         pm_runtime_put_sync(&pdev->dev);
 420         dw_i2c_plat_pm_cleanup(dev);
 421
 422         reset_control_assert(dev->rst);
 423
 424         return 0;
 425 }
 426
 427 #ifdef CONFIG_PM_SLEEP
 428 static int dw_i2c_plat_prepare(struct device *dev)
 429 {
 430         /*
 431          * If the ACPI companion device object is present for this device, it
 432          * may be accessed during suspend and resume of other devices via I2C
 433          * operation regions, so tell the PM core and middle layers to avoid
 434          * skipping system suspend/resume callbacks for it in that case.
 435          */
 436         return !has_acpi_companion(dev);
 437 }
 438
 439 static void dw_i2c_plat_complete(struct device *dev)
 440 {
 441         /*
 442          * The device can only be in runtime suspend at this point if it has not
 443          * been resumed throughout the ending system suspend/resume cycle, so if
 444          * the platform firmware might mess up with it, request the runtime PM
 445          * framework to resume it.
 446          */
 447         if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
 448                 pm_request_resume(dev);
 449 }
 450 #else
 451 #define dw_i2c_plat_prepare     NULL
 452 #define dw_i2c_plat_complete    NULL
 453 #endif
 454
 455 #ifdef CONFIG_PM
 456 static int dw_i2c_plat_suspend(struct device *dev)
 457 {
 458         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 459
 460         i_dev->suspended = true;
 461
 462         if (i_dev->shared_with_punit)
 463                 return 0;
 464
 465         i_dev->disable(i_dev);
 466         i2c_dw_prepare_clk(i_dev, false);
 467
 468         return 0;
 469 }
 470
 471 static int dw_i2c_plat_resume(struct device *dev)
 472 {
 473         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 474
 475         if (!i_dev->shared_with_punit)
 476                 i2c_dw_prepare_clk(i_dev, true);
 477
 478         i_dev->init(i_dev);
 479         i_dev->suspended = false;
 480
 481         return 0;
 482 }
 483
 484 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 485         .prepare = dw_i2c_plat_prepare,
 486         .complete = dw_i2c_plat_complete,
 487         SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
 488         SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
 489 };
 490
 491 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
 492 #else
 493 #define DW_I2C_DEV_PMOPS NULL
 494 #endif
 495
 496 /* Work with hotplug and coldplug */
 497 MODULE_ALIAS("platform:i2c_designware");
 498
 499 static struct platform_driver dw_i2c_driver = {
 500         .probe = dw_i2c_plat_probe,
 501         .remove = dw_i2c_plat_remove,
 502         .driver         = {
 503                 .name   = "i2c_designware",
 504                 .of_match_table = of_match_ptr(dw_i2c_of_match),
 505                 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 506                 .pm     = DW_I2C_DEV_PMOPS,
 507         },
 508 };
 509
 510 static int __init dw_i2c_init_driver(void)
 511 {
 512         return platform_driver_register(&dw_i2c_driver);
 513 }
 514 subsys_initcall(dw_i2c_init_driver);
 515
 516 static void __exit dw_i2c_exit_driver(void)
 517 {
 518         platform_driver_unregister(&dw_i2c_driver);
 519 }
 520 module_exit(dw_i2c_exit_driver);
 521
 522 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 523 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
 524 MODULE_LICENSE("GPL");