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_device.h> 26 #include <linux/pm.h> 27 #include <linux/pm_runtime.h> 28 #include <linux/property.h> 29 #include <linux/regmap.h> 30 #include <linux/reset.h> 31 #include <linux/sched.h> 32 #include <linux/slab.h> 33 #include <linux/suspend.h> 34 #include <linux/units.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) / KILO; 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 { "AMDI0019", ACCESS_INTR_MASK | ARBITRATION_SEMAPHORE }, 54 { "AMDI0510", 0 }, 55 { "APMC0D0F", 0 }, 56 { "HISI02A1", 0 }, 57 { "HISI02A2", 0 }, 58 { "HISI02A3", 0 }, 59 { "HYGO0010", ACCESS_INTR_MASK }, 60 { } 61 }; 62 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); 63 #endif 64 65 #ifdef CONFIG_OF 66 #define BT1_I2C_CTL 0x100 67 #define BT1_I2C_CTL_ADDR_MASK GENMASK(7, 0) 68 #define BT1_I2C_CTL_WR BIT(8) 69 #define BT1_I2C_CTL_GO BIT(31) 70 #define BT1_I2C_DI 0x104 71 #define BT1_I2C_DO 0x108 72 73 static int bt1_i2c_read(void *context, unsigned int reg, unsigned int *val) 74 { 75 struct dw_i2c_dev *dev = context; 76 int ret; 77 78 /* 79 * Note these methods shouldn't ever fail because the system controller 80 * registers are memory mapped. We check the return value just in case. 81 */ 82 ret = regmap_write(dev->sysmap, BT1_I2C_CTL, 83 BT1_I2C_CTL_GO | (reg & BT1_I2C_CTL_ADDR_MASK)); 84 if (ret) 85 return ret; 86 87 return regmap_read(dev->sysmap, BT1_I2C_DO, val); 88 } 89 90 static int bt1_i2c_write(void *context, unsigned int reg, unsigned int val) 91 { 92 struct dw_i2c_dev *dev = context; 93 int ret; 94 95 ret = regmap_write(dev->sysmap, BT1_I2C_DI, val); 96 if (ret) 97 return ret; 98 99 return regmap_write(dev->sysmap, BT1_I2C_CTL, 100 BT1_I2C_CTL_GO | BT1_I2C_CTL_WR | (reg & BT1_I2C_CTL_ADDR_MASK)); 101 } 102 103 static struct regmap_config bt1_i2c_cfg = { 104 .reg_bits = 32, 105 .val_bits = 32, 106 .reg_stride = 4, 107 .fast_io = true, 108 .reg_read = bt1_i2c_read, 109 .reg_write = bt1_i2c_write, 110 .max_register = DW_IC_COMP_TYPE, 111 }; 112 113 static int bt1_i2c_request_regs(struct dw_i2c_dev *dev) 114 { 115 dev->sysmap = syscon_node_to_regmap(dev->dev->of_node->parent); 116 if (IS_ERR(dev->sysmap)) 117 return PTR_ERR(dev->sysmap); 118 119 dev->map = devm_regmap_init(dev->dev, NULL, dev, &bt1_i2c_cfg); 120 return PTR_ERR_OR_ZERO(dev->map); 121 } 122 123 #define MSCC_ICPU_CFG_TWI_DELAY 0x0 124 #define MSCC_ICPU_CFG_TWI_DELAY_ENABLE BIT(0) 125 #define MSCC_ICPU_CFG_TWI_SPIKE_FILTER 0x4 126 127 static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev) 128 { 129 writel((dev->sda_hold_time << 1) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE, 130 dev->ext + MSCC_ICPU_CFG_TWI_DELAY); 131 132 return 0; 133 } 134 135 static int dw_i2c_of_configure(struct platform_device *pdev) 136 { 137 struct dw_i2c_dev *dev = platform_get_drvdata(pdev); 138 139 switch (dev->flags & MODEL_MASK) { 140 case MODEL_MSCC_OCELOT: 141 dev->ext = devm_platform_ioremap_resource(pdev, 1); 142 if (!IS_ERR(dev->ext)) 143 dev->set_sda_hold_time = mscc_twi_set_sda_hold_time; 144 break; 145 default: 146 break; 147 } 148 149 return 0; 150 } 151 152 static const struct of_device_id dw_i2c_of_match[] = { 153 { .compatible = "snps,designware-i2c", }, 154 { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT }, 155 { .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 }, 156 {}, 157 }; 158 MODULE_DEVICE_TABLE(of, dw_i2c_of_match); 159 #else 160 static int bt1_i2c_request_regs(struct dw_i2c_dev *dev) 161 { 162 return -ENODEV; 163 } 164 165 static inline int dw_i2c_of_configure(struct platform_device *pdev) 166 { 167 return -ENODEV; 168 } 169 #endif 170 171 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev) 172 { 173 pm_runtime_disable(dev->dev); 174 175 if (dev->shared_with_punit) 176 pm_runtime_put_noidle(dev->dev); 177 } 178 179 static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev) 180 { 181 struct platform_device *pdev = to_platform_device(dev->dev); 182 int ret; 183 184 switch (dev->flags & MODEL_MASK) { 185 case MODEL_BAIKAL_BT1: 186 ret = bt1_i2c_request_regs(dev); 187 break; 188 default: 189 dev->base = devm_platform_ioremap_resource(pdev, 0); 190 ret = PTR_ERR_OR_ZERO(dev->base); 191 break; 192 } 193 194 return ret; 195 } 196 197 static const struct dmi_system_id dw_i2c_hwmon_class_dmi[] = { 198 { 199 .ident = "Qtechnology QT5222", 200 .matches = { 201 DMI_MATCH(DMI_SYS_VENDOR, "Qtechnology"), 202 DMI_MATCH(DMI_PRODUCT_NAME, "QT5222"), 203 }, 204 }, 205 { } /* terminate list */ 206 }; 207 208 static const struct i2c_dw_semaphore_callbacks i2c_dw_semaphore_cb_table[] = { 209 #ifdef CONFIG_I2C_DESIGNWARE_BAYTRAIL 210 { 211 .probe = i2c_dw_baytrail_probe_lock_support, 212 }, 213 #endif 214 #ifdef CONFIG_I2C_DESIGNWARE_AMDPSP 215 { 216 .probe = i2c_dw_amdpsp_probe_lock_support, 217 }, 218 #endif 219 {} 220 }; 221 222 static int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) 223 { 224 const struct i2c_dw_semaphore_callbacks *ptr; 225 int i = 0; 226 int ret; 227 228 ptr = i2c_dw_semaphore_cb_table; 229 230 dev->semaphore_idx = -1; 231 232 while (ptr->probe) { 233 ret = ptr->probe(dev); 234 if (ret) { 235 /* 236 * If there is no semaphore device attached to this 237 * controller, we shouldn't abort general i2c_controller 238 * probe. 239 */ 240 if (ret != -ENODEV) 241 return ret; 242 243 i++; 244 ptr++; 245 continue; 246 } 247 248 dev->semaphore_idx = i; 249 break; 250 } 251 252 return 0; 253 } 254 255 static void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev) 256 { 257 if (dev->semaphore_idx < 0) 258 return; 259 260 if (i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove) 261 i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove(dev); 262 } 263 264 static int dw_i2c_plat_probe(struct platform_device *pdev) 265 { 266 struct i2c_adapter *adap; 267 struct dw_i2c_dev *dev; 268 struct i2c_timings *t; 269 int irq, ret; 270 271 irq = platform_get_irq(pdev, 0); 272 if (irq < 0) 273 return irq; 274 275 dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); 276 if (!dev) 277 return -ENOMEM; 278 279 dev->flags = (uintptr_t)device_get_match_data(&pdev->dev); 280 dev->dev = &pdev->dev; 281 dev->irq = irq; 282 platform_set_drvdata(pdev, dev); 283 284 ret = dw_i2c_plat_request_regs(dev); 285 if (ret) 286 return ret; 287 288 dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL); 289 if (IS_ERR(dev->rst)) 290 return PTR_ERR(dev->rst); 291 292 reset_control_deassert(dev->rst); 293 294 t = &dev->timings; 295 i2c_parse_fw_timings(&pdev->dev, t, false); 296 297 i2c_dw_adjust_bus_speed(dev); 298 299 if (pdev->dev.of_node) 300 dw_i2c_of_configure(pdev); 301 302 if (has_acpi_companion(&pdev->dev)) 303 i2c_dw_acpi_configure(&pdev->dev); 304 305 ret = i2c_dw_validate_speed(dev); 306 if (ret) 307 goto exit_reset; 308 309 ret = i2c_dw_probe_lock_support(dev); 310 if (ret) 311 goto exit_reset; 312 313 i2c_dw_configure(dev); 314 315 /* Optional interface clock */ 316 dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk"); 317 if (IS_ERR(dev->pclk)) { 318 ret = PTR_ERR(dev->pclk); 319 goto exit_reset; 320 } 321 322 dev->clk = devm_clk_get_optional(&pdev->dev, NULL); 323 if (IS_ERR(dev->clk)) { 324 ret = PTR_ERR(dev->clk); 325 goto exit_reset; 326 } 327 328 ret = i2c_dw_prepare_clk(dev, true); 329 if (ret) 330 goto exit_reset; 331 332 if (dev->clk) { 333 u64 clk_khz; 334 335 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; 336 clk_khz = dev->get_clk_rate_khz(dev); 337 338 if (!dev->sda_hold_time && t->sda_hold_ns) 339 dev->sda_hold_time = 340 DIV_S64_ROUND_CLOSEST(clk_khz * t->sda_hold_ns, MICRO); 341 } 342 343 adap = &dev->adapter; 344 adap->owner = THIS_MODULE; 345 adap->class = dmi_check_system(dw_i2c_hwmon_class_dmi) ? 346 I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED; 347 ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev)); 348 adap->dev.of_node = pdev->dev.of_node; 349 adap->nr = -1; 350 351 if (dev->flags & ACCESS_NO_IRQ_SUSPEND) { 352 dev_pm_set_driver_flags(&pdev->dev, 353 DPM_FLAG_SMART_PREPARE); 354 } else { 355 dev_pm_set_driver_flags(&pdev->dev, 356 DPM_FLAG_SMART_PREPARE | 357 DPM_FLAG_SMART_SUSPEND); 358 } 359 360 device_enable_async_suspend(&pdev->dev); 361 362 /* The code below assumes runtime PM to be disabled. */ 363 WARN_ON(pm_runtime_enabled(&pdev->dev)); 364 365 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); 366 pm_runtime_use_autosuspend(&pdev->dev); 367 pm_runtime_set_active(&pdev->dev); 368 369 if (dev->shared_with_punit) 370 pm_runtime_get_noresume(&pdev->dev); 371 372 pm_runtime_enable(&pdev->dev); 373 374 ret = i2c_dw_probe(dev); 375 if (ret) 376 goto exit_probe; 377 378 return ret; 379 380 exit_probe: 381 dw_i2c_plat_pm_cleanup(dev); 382 exit_reset: 383 reset_control_assert(dev->rst); 384 return ret; 385 } 386 387 static int dw_i2c_plat_remove(struct platform_device *pdev) 388 { 389 struct dw_i2c_dev *dev = platform_get_drvdata(pdev); 390 391 pm_runtime_get_sync(&pdev->dev); 392 393 i2c_del_adapter(&dev->adapter); 394 395 dev->disable(dev); 396 397 pm_runtime_dont_use_autosuspend(&pdev->dev); 398 pm_runtime_put_sync(&pdev->dev); 399 dw_i2c_plat_pm_cleanup(dev); 400 401 i2c_dw_remove_lock_support(dev); 402 403 reset_control_assert(dev->rst); 404 405 return 0; 406 } 407 408 #ifdef CONFIG_PM_SLEEP 409 static int dw_i2c_plat_prepare(struct device *dev) 410 { 411 /* 412 * If the ACPI companion device object is present for this device, it 413 * may be accessed during suspend and resume of other devices via I2C 414 * operation regions, so tell the PM core and middle layers to avoid 415 * skipping system suspend/resume callbacks for it in that case. 416 */ 417 return !has_acpi_companion(dev); 418 } 419 #else 420 #define dw_i2c_plat_prepare NULL 421 #endif 422 423 #ifdef CONFIG_PM 424 static int dw_i2c_plat_runtime_suspend(struct device *dev) 425 { 426 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 427 428 if (i_dev->shared_with_punit) 429 return 0; 430 431 i_dev->disable(i_dev); 432 i2c_dw_prepare_clk(i_dev, false); 433 434 return 0; 435 } 436 437 static int __maybe_unused dw_i2c_plat_suspend(struct device *dev) 438 { 439 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 440 441 i2c_mark_adapter_suspended(&i_dev->adapter); 442 443 return dw_i2c_plat_runtime_suspend(dev); 444 } 445 446 static int dw_i2c_plat_runtime_resume(struct device *dev) 447 { 448 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 449 450 if (!i_dev->shared_with_punit) 451 i2c_dw_prepare_clk(i_dev, true); 452 453 i_dev->init(i_dev); 454 455 return 0; 456 } 457 458 static int __maybe_unused dw_i2c_plat_resume(struct device *dev) 459 { 460 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 461 462 dw_i2c_plat_runtime_resume(dev); 463 i2c_mark_adapter_resumed(&i_dev->adapter); 464 465 return 0; 466 } 467 468 static const struct dev_pm_ops dw_i2c_dev_pm_ops = { 469 .prepare = dw_i2c_plat_prepare, 470 SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume) 471 SET_RUNTIME_PM_OPS(dw_i2c_plat_runtime_suspend, dw_i2c_plat_runtime_resume, NULL) 472 }; 473 474 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops) 475 #else 476 #define DW_I2C_DEV_PMOPS NULL 477 #endif 478 479 /* Work with hotplug and coldplug */ 480 MODULE_ALIAS("platform:i2c_designware"); 481 482 static struct platform_driver dw_i2c_driver = { 483 .probe = dw_i2c_plat_probe, 484 .remove = dw_i2c_plat_remove, 485 .driver = { 486 .name = "i2c_designware", 487 .of_match_table = of_match_ptr(dw_i2c_of_match), 488 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match), 489 .pm = DW_I2C_DEV_PMOPS, 490 }, 491 }; 492 493 static int __init dw_i2c_init_driver(void) 494 { 495 return platform_driver_register(&dw_i2c_driver); 496 } 497 subsys_initcall(dw_i2c_init_driver); 498 499 static void __exit dw_i2c_exit_driver(void) 500 { 501 platform_driver_unregister(&dw_i2c_driver); 502 } 503 module_exit(dw_i2c_exit_driver); 504 505 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); 506 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); 507 MODULE_LICENSE("GPL"); 508