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 int txgbe_i2c_request_regs(struct dw_i2c_dev *dev) 172 { 173 dev->map = dev_get_regmap(dev->dev->parent, NULL); 174 if (!dev->map) 175 return -ENODEV; 176 177 return 0; 178 } 179 180 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev) 181 { 182 pm_runtime_disable(dev->dev); 183 184 if (dev->shared_with_punit) 185 pm_runtime_put_noidle(dev->dev); 186 } 187 188 static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev) 189 { 190 struct platform_device *pdev = to_platform_device(dev->dev); 191 int ret; 192 193 switch (dev->flags & MODEL_MASK) { 194 case MODEL_BAIKAL_BT1: 195 ret = bt1_i2c_request_regs(dev); 196 break; 197 case MODEL_WANGXUN_SP: 198 ret = txgbe_i2c_request_regs(dev); 199 break; 200 default: 201 dev->base = devm_platform_ioremap_resource(pdev, 0); 202 ret = PTR_ERR_OR_ZERO(dev->base); 203 break; 204 } 205 206 return ret; 207 } 208 209 static const struct dmi_system_id dw_i2c_hwmon_class_dmi[] = { 210 { 211 .ident = "Qtechnology QT5222", 212 .matches = { 213 DMI_MATCH(DMI_SYS_VENDOR, "Qtechnology"), 214 DMI_MATCH(DMI_PRODUCT_NAME, "QT5222"), 215 }, 216 }, 217 { } /* terminate list */ 218 }; 219 220 static const struct i2c_dw_semaphore_callbacks i2c_dw_semaphore_cb_table[] = { 221 #ifdef CONFIG_I2C_DESIGNWARE_BAYTRAIL 222 { 223 .probe = i2c_dw_baytrail_probe_lock_support, 224 }, 225 #endif 226 #ifdef CONFIG_I2C_DESIGNWARE_AMDPSP 227 { 228 .probe = i2c_dw_amdpsp_probe_lock_support, 229 }, 230 #endif 231 {} 232 }; 233 234 static int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) 235 { 236 const struct i2c_dw_semaphore_callbacks *ptr; 237 int i = 0; 238 int ret; 239 240 ptr = i2c_dw_semaphore_cb_table; 241 242 dev->semaphore_idx = -1; 243 244 while (ptr->probe) { 245 ret = ptr->probe(dev); 246 if (ret) { 247 /* 248 * If there is no semaphore device attached to this 249 * controller, we shouldn't abort general i2c_controller 250 * probe. 251 */ 252 if (ret != -ENODEV) 253 return ret; 254 255 i++; 256 ptr++; 257 continue; 258 } 259 260 dev->semaphore_idx = i; 261 break; 262 } 263 264 return 0; 265 } 266 267 static void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev) 268 { 269 if (dev->semaphore_idx < 0) 270 return; 271 272 if (i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove) 273 i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove(dev); 274 } 275 276 static int dw_i2c_plat_probe(struct platform_device *pdev) 277 { 278 struct i2c_adapter *adap; 279 struct dw_i2c_dev *dev; 280 struct i2c_timings *t; 281 int irq, ret; 282 283 irq = platform_get_irq(pdev, 0); 284 if (irq < 0) 285 return irq; 286 287 dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); 288 if (!dev) 289 return -ENOMEM; 290 291 dev->flags = (uintptr_t)device_get_match_data(&pdev->dev); 292 if (device_property_present(&pdev->dev, "wx,i2c-snps-model")) 293 dev->flags = MODEL_WANGXUN_SP | ACCESS_POLLING; 294 295 dev->dev = &pdev->dev; 296 dev->irq = irq; 297 platform_set_drvdata(pdev, dev); 298 299 ret = dw_i2c_plat_request_regs(dev); 300 if (ret) 301 return ret; 302 303 dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL); 304 if (IS_ERR(dev->rst)) 305 return PTR_ERR(dev->rst); 306 307 reset_control_deassert(dev->rst); 308 309 t = &dev->timings; 310 i2c_parse_fw_timings(&pdev->dev, t, false); 311 312 i2c_dw_adjust_bus_speed(dev); 313 314 if (pdev->dev.of_node) 315 dw_i2c_of_configure(pdev); 316 317 if (has_acpi_companion(&pdev->dev)) 318 i2c_dw_acpi_configure(&pdev->dev); 319 320 ret = i2c_dw_validate_speed(dev); 321 if (ret) 322 goto exit_reset; 323 324 ret = i2c_dw_probe_lock_support(dev); 325 if (ret) 326 goto exit_reset; 327 328 i2c_dw_configure(dev); 329 330 /* Optional interface clock */ 331 dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk"); 332 if (IS_ERR(dev->pclk)) { 333 ret = PTR_ERR(dev->pclk); 334 goto exit_reset; 335 } 336 337 dev->clk = devm_clk_get_optional(&pdev->dev, NULL); 338 if (IS_ERR(dev->clk)) { 339 ret = PTR_ERR(dev->clk); 340 goto exit_reset; 341 } 342 343 ret = i2c_dw_prepare_clk(dev, true); 344 if (ret) 345 goto exit_reset; 346 347 if (dev->clk) { 348 u64 clk_khz; 349 350 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; 351 clk_khz = dev->get_clk_rate_khz(dev); 352 353 if (!dev->sda_hold_time && t->sda_hold_ns) 354 dev->sda_hold_time = 355 DIV_S64_ROUND_CLOSEST(clk_khz * t->sda_hold_ns, MICRO); 356 } 357 358 adap = &dev->adapter; 359 adap->owner = THIS_MODULE; 360 adap->class = dmi_check_system(dw_i2c_hwmon_class_dmi) ? 361 I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED; 362 ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev)); 363 adap->dev.of_node = pdev->dev.of_node; 364 adap->nr = -1; 365 366 if (dev->flags & ACCESS_NO_IRQ_SUSPEND) { 367 dev_pm_set_driver_flags(&pdev->dev, 368 DPM_FLAG_SMART_PREPARE); 369 } else { 370 dev_pm_set_driver_flags(&pdev->dev, 371 DPM_FLAG_SMART_PREPARE | 372 DPM_FLAG_SMART_SUSPEND); 373 } 374 375 device_enable_async_suspend(&pdev->dev); 376 377 /* The code below assumes runtime PM to be disabled. */ 378 WARN_ON(pm_runtime_enabled(&pdev->dev)); 379 380 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); 381 pm_runtime_use_autosuspend(&pdev->dev); 382 pm_runtime_set_active(&pdev->dev); 383 384 if (dev->shared_with_punit) 385 pm_runtime_get_noresume(&pdev->dev); 386 387 pm_runtime_enable(&pdev->dev); 388 389 ret = i2c_dw_probe(dev); 390 if (ret) 391 goto exit_probe; 392 393 return ret; 394 395 exit_probe: 396 dw_i2c_plat_pm_cleanup(dev); 397 exit_reset: 398 reset_control_assert(dev->rst); 399 return ret; 400 } 401 402 static void dw_i2c_plat_remove(struct platform_device *pdev) 403 { 404 struct dw_i2c_dev *dev = platform_get_drvdata(pdev); 405 406 pm_runtime_get_sync(&pdev->dev); 407 408 i2c_del_adapter(&dev->adapter); 409 410 dev->disable(dev); 411 412 pm_runtime_dont_use_autosuspend(&pdev->dev); 413 pm_runtime_put_sync(&pdev->dev); 414 dw_i2c_plat_pm_cleanup(dev); 415 416 i2c_dw_remove_lock_support(dev); 417 418 reset_control_assert(dev->rst); 419 } 420 421 static int dw_i2c_plat_prepare(struct device *dev) 422 { 423 /* 424 * If the ACPI companion device object is present for this device, it 425 * may be accessed during suspend and resume of other devices via I2C 426 * operation regions, so tell the PM core and middle layers to avoid 427 * skipping system suspend/resume callbacks for it in that case. 428 */ 429 return !has_acpi_companion(dev); 430 } 431 432 static int dw_i2c_plat_runtime_suspend(struct device *dev) 433 { 434 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 435 436 if (i_dev->shared_with_punit) 437 return 0; 438 439 i_dev->disable(i_dev); 440 i2c_dw_prepare_clk(i_dev, false); 441 442 return 0; 443 } 444 445 static int dw_i2c_plat_suspend(struct device *dev) 446 { 447 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 448 449 i2c_mark_adapter_suspended(&i_dev->adapter); 450 451 return dw_i2c_plat_runtime_suspend(dev); 452 } 453 454 static int dw_i2c_plat_runtime_resume(struct device *dev) 455 { 456 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 457 458 if (!i_dev->shared_with_punit) 459 i2c_dw_prepare_clk(i_dev, true); 460 461 i_dev->init(i_dev); 462 463 return 0; 464 } 465 466 static int dw_i2c_plat_resume(struct device *dev) 467 { 468 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 469 470 dw_i2c_plat_runtime_resume(dev); 471 i2c_mark_adapter_resumed(&i_dev->adapter); 472 473 return 0; 474 } 475 476 static const struct dev_pm_ops dw_i2c_dev_pm_ops = { 477 .prepare = pm_sleep_ptr(dw_i2c_plat_prepare), 478 LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume) 479 RUNTIME_PM_OPS(dw_i2c_plat_runtime_suspend, dw_i2c_plat_runtime_resume, NULL) 480 }; 481 482 /* Work with hotplug and coldplug */ 483 MODULE_ALIAS("platform:i2c_designware"); 484 485 static struct platform_driver dw_i2c_driver = { 486 .probe = dw_i2c_plat_probe, 487 .remove_new = dw_i2c_plat_remove, 488 .driver = { 489 .name = "i2c_designware", 490 .of_match_table = of_match_ptr(dw_i2c_of_match), 491 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match), 492 .pm = pm_ptr(&dw_i2c_dev_pm_ops), 493 }, 494 }; 495 496 static int __init dw_i2c_init_driver(void) 497 { 498 return platform_driver_register(&dw_i2c_driver); 499 } 500 subsys_initcall(dw_i2c_init_driver); 501 502 static void __exit dw_i2c_exit_driver(void) 503 { 504 platform_driver_unregister(&dw_i2c_driver); 505 } 506 module_exit(dw_i2c_exit_driver); 507 508 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); 509 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); 510 MODULE_LICENSE("GPL"); 511