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/mfd/syscon.h>
  23 #include <linux/module.h>
  24 #include <linux/of.h>
  25 #include <linux/platform_data/i2c-designware.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/pm.h>
  28 #include <linux/pm_runtime.h>
  29 #include <linux/property.h>
  30 #include <linux/regmap.h>
  31 #include <linux/reset.h>
  32 #include <linux/sched.h>
  33 #include <linux/slab.h>
  34 #include <linux/suspend.h>
  35
  36 #include "i2c-designware-core.h"
  37
  38 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
  39 {
  40         return clk_get_rate(dev->clk)/1000;
  41 }
  42
  43 #ifdef CONFIG_ACPI
  44 static const struct acpi_device_id dw_i2c_acpi_match[] = {
  45         { "INT33C2", 0 },
  46         { "INT33C3", 0 },
  47         { "INT3432", 0 },
  48         { "INT3433", 0 },
  49         { "80860F41", ACCESS_NO_IRQ_SUSPEND },
  50         { "808622C1", ACCESS_NO_IRQ_SUSPEND },
  51         { "AMD0010", ACCESS_INTR_MASK },
  52         { "AMDI0010", ACCESS_INTR_MASK },
  53         { "AMDI0510", 0 },
  54         { "APMC0D0F", 0 },
  55         { "HISI02A1", 0 },
  56         { "HISI02A2", 0 },
  57         { "HISI02A3", 0 },
  58         { "HYGO0010", ACCESS_INTR_MASK },
  59         { }
  60 };
  61 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
  62 #endif
  63
  64 #ifdef CONFIG_OF
  65 #define BT1_I2C_CTL                     0x100
  66 #define BT1_I2C_CTL_ADDR_MASK           GENMASK(7, 0)
  67 #define BT1_I2C_CTL_WR                  BIT(8)
  68 #define BT1_I2C_CTL_GO                  BIT(31)
  69 #define BT1_I2C_DI                      0x104
  70 #define BT1_I2C_DO                      0x108
  71
  72 static int bt1_i2c_read(void *context, unsigned int reg, unsigned int *val)
  73 {
  74         struct dw_i2c_dev *dev = context;
  75         int ret;
  76
  77         /*
  78          * Note these methods shouldn't ever fail because the system controller
  79          * registers are memory mapped. We check the return value just in case.
  80          */
  81         ret = regmap_write(dev->sysmap, BT1_I2C_CTL,
  82                            BT1_I2C_CTL_GO | (reg & BT1_I2C_CTL_ADDR_MASK));
  83         if (ret)
  84                 return ret;
  85
  86         return regmap_read(dev->sysmap, BT1_I2C_DO, val);
  87 }
  88
  89 static int bt1_i2c_write(void *context, unsigned int reg, unsigned int val)
  90 {
  91         struct dw_i2c_dev *dev = context;
  92         int ret;
  93
  94         ret = regmap_write(dev->sysmap, BT1_I2C_DI, val);
  95         if (ret)
  96                 return ret;
  97
  98         return regmap_write(dev->sysmap, BT1_I2C_CTL,
  99                 BT1_I2C_CTL_GO | BT1_I2C_CTL_WR | (reg & BT1_I2C_CTL_ADDR_MASK));
 100 }
 101
 102 static struct regmap_config bt1_i2c_cfg = {
 103         .reg_bits = 32,
 104         .val_bits = 32,
 105         .reg_stride = 4,
 106         .fast_io = true,
 107         .reg_read = bt1_i2c_read,
 108         .reg_write = bt1_i2c_write,
 109         .max_register = DW_IC_COMP_TYPE,
 110 };
 111
 112 static int bt1_i2c_request_regs(struct dw_i2c_dev *dev)
 113 {
 114         dev->sysmap = syscon_node_to_regmap(dev->dev->of_node->parent);
 115         if (IS_ERR(dev->sysmap))
 116                 return PTR_ERR(dev->sysmap);
 117
 118         dev->map = devm_regmap_init(dev->dev, NULL, dev, &bt1_i2c_cfg);
 119         return PTR_ERR_OR_ZERO(dev->map);
 120 }
 121
 122 #define MSCC_ICPU_CFG_TWI_DELAY         0x0
 123 #define MSCC_ICPU_CFG_TWI_DELAY_ENABLE  BIT(0)
 124 #define MSCC_ICPU_CFG_TWI_SPIKE_FILTER  0x4
 125
 126 static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev)
 127 {
 128         writel((dev->sda_hold_time << 1) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE,
 129                dev->ext + MSCC_ICPU_CFG_TWI_DELAY);
 130
 131         return 0;
 132 }
 133
 134 static int dw_i2c_of_configure(struct platform_device *pdev)
 135 {
 136         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 137
 138         switch (dev->flags & MODEL_MASK) {
 139         case MODEL_MSCC_OCELOT:
 140                 dev->ext = devm_platform_ioremap_resource(pdev, 1);
 141                 if (!IS_ERR(dev->ext))
 142                         dev->set_sda_hold_time = mscc_twi_set_sda_hold_time;
 143                 break;
 144         default:
 145                 break;
 146         }
 147
 148         return 0;
 149 }
 150
 151 static const struct of_device_id dw_i2c_of_match[] = {
 152         { .compatible = "snps,designware-i2c", },
 153         { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
 154         { .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 },
 155         {},
 156 };
 157 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
 158 #else
 159 static int bt1_i2c_request_regs(struct dw_i2c_dev *dev)
 160 {
 161         return -ENODEV;
 162 }
 163
 164 static inline int dw_i2c_of_configure(struct platform_device *pdev)
 165 {
 166         return -ENODEV;
 167 }
 168 #endif
 169
 170 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
 171 {
 172         pm_runtime_disable(dev->dev);
 173
 174         if (dev->shared_with_punit)
 175                 pm_runtime_put_noidle(dev->dev);
 176 }
 177
 178 static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev)
 179 {
 180         struct platform_device *pdev = to_platform_device(dev->dev);
 181         int ret;
 182
 183         switch (dev->flags & MODEL_MASK) {
 184         case MODEL_BAIKAL_BT1:
 185                 ret = bt1_i2c_request_regs(dev);
 186                 break;
 187         default:
 188                 dev->base = devm_platform_ioremap_resource(pdev, 0);
 189                 ret = PTR_ERR_OR_ZERO(dev->base);
 190                 break;
 191         }
 192
 193         return ret;
 194 }
 195
 196 static const struct dmi_system_id dw_i2c_hwmon_class_dmi[] = {
 197         {
 198                 .ident = "Qtechnology QT5222",
 199                 .matches = {
 200                         DMI_MATCH(DMI_SYS_VENDOR, "Qtechnology"),
 201                         DMI_MATCH(DMI_PRODUCT_NAME, "QT5222"),
 202                 },
 203         },
 204         { } /* terminate list */
 205 };
 206
 207 static int dw_i2c_plat_probe(struct platform_device *pdev)
 208 {
 209         struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
 210         struct i2c_adapter *adap;
 211         struct dw_i2c_dev *dev;
 212         struct i2c_timings *t;
 213         int irq, ret;
 214
 215         irq = platform_get_irq(pdev, 0);
 216         if (irq < 0)
 217                 return irq;
 218
 219         dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
 220         if (!dev)
 221                 return -ENOMEM;
 222
 223         dev->flags = (uintptr_t)device_get_match_data(&pdev->dev);
 224         dev->dev = &pdev->dev;
 225         dev->irq = irq;
 226         platform_set_drvdata(pdev, dev);
 227
 228         ret = dw_i2c_plat_request_regs(dev);
 229         if (ret)
 230                 return ret;
 231
 232         dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
 233         if (IS_ERR(dev->rst))
 234                 return PTR_ERR(dev->rst);
 235
 236         reset_control_deassert(dev->rst);
 237
 238         t = &dev->timings;
 239         if (pdata)
 240                 t->bus_freq_hz = pdata->i2c_scl_freq;
 241         else
 242                 i2c_parse_fw_timings(&pdev->dev, t, false);
 243
 244         i2c_dw_adjust_bus_speed(dev);
 245
 246         if (pdev->dev.of_node)
 247                 dw_i2c_of_configure(pdev);
 248
 249         if (has_acpi_companion(&pdev->dev))
 250                 i2c_dw_acpi_configure(&pdev->dev);
 251
 252         ret = i2c_dw_validate_speed(dev);
 253         if (ret)
 254                 goto exit_reset;
 255
 256         ret = i2c_dw_probe_lock_support(dev);
 257         if (ret)
 258                 goto exit_reset;
 259
 260         i2c_dw_configure(dev);
 261
 262         /* Optional interface clock */
 263         dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
 264         if (IS_ERR(dev->pclk)) {
 265                 ret = PTR_ERR(dev->pclk);
 266                 goto exit_reset;
 267         }
 268
 269         dev->clk = devm_clk_get_optional(&pdev->dev, NULL);
 270         if (IS_ERR(dev->clk)) {
 271                 ret = PTR_ERR(dev->clk);
 272                 goto exit_reset;
 273         }
 274
 275         ret = i2c_dw_prepare_clk(dev, true);
 276         if (ret)
 277                 goto exit_reset;
 278
 279         if (dev->clk) {
 280                 u64 clk_khz;
 281
 282                 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
 283                 clk_khz = dev->get_clk_rate_khz(dev);
 284
 285                 if (!dev->sda_hold_time && t->sda_hold_ns)
 286                         dev->sda_hold_time =
 287                                 div_u64(clk_khz * t->sda_hold_ns + 500000, 1000000);
 288         }
 289
 290         adap = &dev->adapter;
 291         adap->owner = THIS_MODULE;
 292         adap->class = dmi_check_system(dw_i2c_hwmon_class_dmi) ?
 293                                         I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED;
 294         ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 295         adap->dev.of_node = pdev->dev.of_node;
 296         adap->nr = -1;
 297
 298         if (dev->flags & ACCESS_NO_IRQ_SUSPEND) {
 299                 dev_pm_set_driver_flags(&pdev->dev,
 300                                         DPM_FLAG_SMART_PREPARE |
 301                                         DPM_FLAG_MAY_SKIP_RESUME);
 302         } else {
 303                 dev_pm_set_driver_flags(&pdev->dev,
 304                                         DPM_FLAG_SMART_PREPARE |
 305                                         DPM_FLAG_SMART_SUSPEND |
 306                                         DPM_FLAG_MAY_SKIP_RESUME);
 307         }
 308
 309         /* The code below assumes runtime PM to be disabled. */
 310         WARN_ON(pm_runtime_enabled(&pdev->dev));
 311
 312         pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
 313         pm_runtime_use_autosuspend(&pdev->dev);
 314         pm_runtime_set_active(&pdev->dev);
 315
 316         if (dev->shared_with_punit)
 317                 pm_runtime_get_noresume(&pdev->dev);
 318
 319         pm_runtime_enable(&pdev->dev);
 320
 321         ret = i2c_dw_probe(dev);
 322         if (ret)
 323                 goto exit_probe;
 324
 325         return ret;
 326
 327 exit_probe:
 328         dw_i2c_plat_pm_cleanup(dev);
 329 exit_reset:
 330         reset_control_assert(dev->rst);
 331         return ret;
 332 }
 333
 334 static int dw_i2c_plat_remove(struct platform_device *pdev)
 335 {
 336         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
 337
 338         pm_runtime_get_sync(&pdev->dev);
 339
 340         i2c_del_adapter(&dev->adapter);
 341
 342         dev->disable(dev);
 343
 344         pm_runtime_dont_use_autosuspend(&pdev->dev);
 345         pm_runtime_put_sync(&pdev->dev);
 346         dw_i2c_plat_pm_cleanup(dev);
 347
 348         reset_control_assert(dev->rst);
 349
 350         return 0;
 351 }
 352
 353 #ifdef CONFIG_PM_SLEEP
 354 static int dw_i2c_plat_prepare(struct device *dev)
 355 {
 356         /*
 357          * If the ACPI companion device object is present for this device, it
 358          * may be accessed during suspend and resume of other devices via I2C
 359          * operation regions, so tell the PM core and middle layers to avoid
 360          * skipping system suspend/resume callbacks for it in that case.
 361          */
 362         return !has_acpi_companion(dev);
 363 }
 364
 365 static void dw_i2c_plat_complete(struct device *dev)
 366 {
 367         /*
 368          * The device can only be in runtime suspend at this point if it has not
 369          * been resumed throughout the ending system suspend/resume cycle, so if
 370          * the platform firmware might mess up with it, request the runtime PM
 371          * framework to resume it.
 372          */
 373         if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
 374                 pm_request_resume(dev);
 375 }
 376 #else
 377 #define dw_i2c_plat_prepare     NULL
 378 #define dw_i2c_plat_complete    NULL
 379 #endif
 380
 381 #ifdef CONFIG_PM
 382 static int dw_i2c_plat_suspend(struct device *dev)
 383 {
 384         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 385
 386         i_dev->suspended = true;
 387
 388         if (i_dev->shared_with_punit)
 389                 return 0;
 390
 391         i_dev->disable(i_dev);
 392         i2c_dw_prepare_clk(i_dev, false);
 393
 394         return 0;
 395 }
 396
 397 static int dw_i2c_plat_resume(struct device *dev)
 398 {
 399         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
 400
 401         if (!i_dev->shared_with_punit)
 402                 i2c_dw_prepare_clk(i_dev, true);
 403
 404         i_dev->init(i_dev);
 405         i_dev->suspended = false;
 406
 407         return 0;
 408 }
 409
 410 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 411         .prepare = dw_i2c_plat_prepare,
 412         .complete = dw_i2c_plat_complete,
 413         SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
 414         SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
 415 };
 416
 417 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
 418 #else
 419 #define DW_I2C_DEV_PMOPS NULL
 420 #endif
 421
 422 /* Work with hotplug and coldplug */
 423 MODULE_ALIAS("platform:i2c_designware");
 424
 425 static struct platform_driver dw_i2c_driver = {
 426         .probe = dw_i2c_plat_probe,
 427         .remove = dw_i2c_plat_remove,
 428         .driver         = {
 429                 .name   = "i2c_designware",
 430                 .of_match_table = of_match_ptr(dw_i2c_of_match),
 431                 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 432                 .pm     = DW_I2C_DEV_PMOPS,
 433         },
 434 };
 435
 436 static int __init dw_i2c_init_driver(void)
 437 {
 438         return platform_driver_register(&dw_i2c_driver);
 439 }
 440 subsys_initcall(dw_i2c_init_driver);
 441
 442 static void __exit dw_i2c_exit_driver(void)
 443 {
 444         platform_driver_unregister(&dw_i2c_driver);
 445 }
 446 module_exit(dw_i2c_exit_driver);
 447
 448 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
 449 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
 450 MODULE_LICENSE("GPL");