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->adapter.nr = -1; 90 dev->tx_fifo_depth = 32; 91 dev->rx_fifo_depth = 32; 92 93 /* 94 * Try to get SDA hold time and *CNT values from an ACPI method for 95 * selected speed modes. 96 */ 97 dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht); 98 dw_i2c_acpi_params(pdev, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht); 99 dw_i2c_acpi_params(pdev, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht); 100 dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht); 101 102 switch (t->bus_freq_hz) { 103 case 100000: 104 dev->sda_hold_time = ss_ht; 105 break; 106 case 1000000: 107 dev->sda_hold_time = fp_ht; 108 break; 109 case 3400000: 110 dev->sda_hold_time = hs_ht; 111 break; 112 case 400000: 113 default: 114 dev->sda_hold_time = fs_ht; 115 break; 116 } 117 118 return 0; 119 } 120 121 static const struct acpi_device_id dw_i2c_acpi_match[] = { 122 { "INT33C2", 0 }, 123 { "INT33C3", 0 }, 124 { "INT3432", 0 }, 125 { "INT3433", 0 }, 126 { "80860F41", ACCESS_NO_IRQ_SUSPEND }, 127 { "808622C1", ACCESS_NO_IRQ_SUSPEND | MODEL_CHERRYTRAIL }, 128 { "AMD0010", ACCESS_INTR_MASK }, 129 { "AMDI0010", ACCESS_INTR_MASK }, 130 { "AMDI0510", 0 }, 131 { "APMC0D0F", 0 }, 132 { "HISI02A1", 0 }, 133 { "HISI02A2", 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, int id) 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 dev->adapter.nr = id; 237 } else if (tx_fifo_depth >= 2) { 238 dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth, 239 tx_fifo_depth); 240 dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth, 241 rx_fifo_depth); 242 } 243 } 244 245 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev) 246 { 247 pm_runtime_disable(dev->dev); 248 249 if (dev->shared_with_punit) 250 pm_runtime_put_noidle(dev->dev); 251 } 252 253 static int dw_i2c_plat_probe(struct platform_device *pdev) 254 { 255 struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev); 256 struct i2c_adapter *adap; 257 struct dw_i2c_dev *dev; 258 struct i2c_timings *t; 259 u32 acpi_speed; 260 struct resource *mem; 261 int i, irq, ret; 262 static const int supported_speeds[] = { 263 0, 100000, 400000, 1000000, 3400000 264 }; 265 266 irq = platform_get_irq(pdev, 0); 267 if (irq < 0) 268 return irq; 269 270 dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); 271 if (!dev) 272 return -ENOMEM; 273 274 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); 275 dev->base = devm_ioremap_resource(&pdev->dev, mem); 276 if (IS_ERR(dev->base)) 277 return PTR_ERR(dev->base); 278 279 dev->dev = &pdev->dev; 280 dev->irq = irq; 281 platform_set_drvdata(pdev, dev); 282 283 dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL); 284 if (IS_ERR(dev->rst)) { 285 if (PTR_ERR(dev->rst) == -EPROBE_DEFER) 286 return -EPROBE_DEFER; 287 } else { 288 reset_control_deassert(dev->rst); 289 } 290 291 t = &dev->timings; 292 if (pdata) 293 t->bus_freq_hz = pdata->i2c_scl_freq; 294 else 295 i2c_parse_fw_timings(&pdev->dev, t, false); 296 297 acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev); 298 /* 299 * Some DSTDs use a non standard speed, round down to the lowest 300 * standard speed. 301 */ 302 for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) { 303 if (acpi_speed < supported_speeds[i]) 304 break; 305 } 306 acpi_speed = supported_speeds[i - 1]; 307 308 /* 309 * Find bus speed from the "clock-frequency" device property, ACPI 310 * or by using fast mode if neither is set. 311 */ 312 if (acpi_speed && t->bus_freq_hz) 313 t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed); 314 else if (acpi_speed || t->bus_freq_hz) 315 t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed); 316 else 317 t->bus_freq_hz = 400000; 318 319 dev->flags |= (uintptr_t)device_get_match_data(&pdev->dev); 320 321 if (pdev->dev.of_node) 322 dw_i2c_of_configure(pdev); 323 324 if (has_acpi_companion(&pdev->dev)) 325 dw_i2c_acpi_configure(pdev); 326 327 /* 328 * Only standard mode at 100kHz, fast mode at 400kHz, 329 * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported. 330 */ 331 if (t->bus_freq_hz != 100000 && t->bus_freq_hz != 400000 && 332 t->bus_freq_hz != 1000000 && t->bus_freq_hz != 3400000) { 333 dev_err(&pdev->dev, 334 "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n", 335 t->bus_freq_hz); 336 ret = -EINVAL; 337 goto exit_reset; 338 } 339 340 ret = i2c_dw_probe_lock_support(dev); 341 if (ret) 342 goto exit_reset; 343 344 if (i2c_detect_slave_mode(&pdev->dev)) 345 i2c_dw_configure_slave(dev); 346 else 347 i2c_dw_configure_master(dev); 348 349 dev->clk = devm_clk_get(&pdev->dev, NULL); 350 if (!i2c_dw_prepare_clk(dev, true)) { 351 u64 clk_khz; 352 353 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; 354 clk_khz = dev->get_clk_rate_khz(dev); 355 356 if (!dev->sda_hold_time && t->sda_hold_ns) 357 dev->sda_hold_time = 358 div_u64(clk_khz * t->sda_hold_ns + 500000, 1000000); 359 } 360 361 dw_i2c_set_fifo_size(dev, pdev->id); 362 363 adap = &dev->adapter; 364 adap->owner = THIS_MODULE; 365 adap->class = I2C_CLASS_DEPRECATED; 366 ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev)); 367 adap->dev.of_node = pdev->dev.of_node; 368 369 dev_pm_set_driver_flags(&pdev->dev, 370 DPM_FLAG_SMART_PREPARE | 371 DPM_FLAG_SMART_SUSPEND | 372 DPM_FLAG_LEAVE_SUSPENDED); 373 374 /* The code below assumes runtime PM to be disabled. */ 375 WARN_ON(pm_runtime_enabled(&pdev->dev)); 376 377 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); 378 pm_runtime_use_autosuspend(&pdev->dev); 379 pm_runtime_set_active(&pdev->dev); 380 381 if (dev->shared_with_punit) 382 pm_runtime_get_noresume(&pdev->dev); 383 384 pm_runtime_enable(&pdev->dev); 385 386 if (dev->mode == DW_IC_SLAVE) 387 ret = i2c_dw_probe_slave(dev); 388 else 389 ret = i2c_dw_probe(dev); 390 391 if (ret) 392 goto exit_probe; 393 394 return ret; 395 396 exit_probe: 397 dw_i2c_plat_pm_cleanup(dev); 398 exit_reset: 399 if (!IS_ERR_OR_NULL(dev->rst)) 400 reset_control_assert(dev->rst); 401 return ret; 402 } 403 404 static int dw_i2c_plat_remove(struct platform_device *pdev) 405 { 406 struct dw_i2c_dev *dev = platform_get_drvdata(pdev); 407 408 pm_runtime_get_sync(&pdev->dev); 409 410 i2c_del_adapter(&dev->adapter); 411 412 dev->disable(dev); 413 414 pm_runtime_dont_use_autosuspend(&pdev->dev); 415 pm_runtime_put_sync(&pdev->dev); 416 dw_i2c_plat_pm_cleanup(dev); 417 418 if (!IS_ERR_OR_NULL(dev->rst)) 419 reset_control_assert(dev->rst); 420 421 return 0; 422 } 423 424 #ifdef CONFIG_PM_SLEEP 425 static int dw_i2c_plat_prepare(struct device *dev) 426 { 427 /* 428 * If the ACPI companion device object is present for this device, it 429 * may be accessed during suspend and resume of other devices via I2C 430 * operation regions, so tell the PM core and middle layers to avoid 431 * skipping system suspend/resume callbacks for it in that case. 432 */ 433 return !has_acpi_companion(dev); 434 } 435 436 static void dw_i2c_plat_complete(struct device *dev) 437 { 438 /* 439 * The device can only be in runtime suspend at this point if it has not 440 * been resumed throughout the ending system suspend/resume cycle, so if 441 * the platform firmware might mess up with it, request the runtime PM 442 * framework to resume it. 443 */ 444 if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) 445 pm_request_resume(dev); 446 } 447 #else 448 #define dw_i2c_plat_prepare NULL 449 #define dw_i2c_plat_complete NULL 450 #endif 451 452 #ifdef CONFIG_PM 453 static int dw_i2c_plat_suspend(struct device *dev) 454 { 455 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); 456 457 if (i_dev->shared_with_punit) 458 return 0; 459 460 i_dev->disable(i_dev); 461 i2c_dw_prepare_clk(i_dev, false); 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 if (!i_dev->shared_with_punit) 471 i2c_dw_prepare_clk(i_dev, true); 472 473 i_dev->init(i_dev); 474 475 return 0; 476 } 477 478 static const struct dev_pm_ops dw_i2c_dev_pm_ops = { 479 .prepare = dw_i2c_plat_prepare, 480 .complete = dw_i2c_plat_complete, 481 SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume) 482 SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL) 483 }; 484 485 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops) 486 #else 487 #define DW_I2C_DEV_PMOPS NULL 488 #endif 489 490 /* Work with hotplug and coldplug */ 491 MODULE_ALIAS("platform:i2c_designware"); 492 493 static struct platform_driver dw_i2c_driver = { 494 .probe = dw_i2c_plat_probe, 495 .remove = dw_i2c_plat_remove, 496 .driver = { 497 .name = "i2c_designware", 498 .of_match_table = of_match_ptr(dw_i2c_of_match), 499 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match), 500 .pm = DW_I2C_DEV_PMOPS, 501 }, 502 }; 503 504 static int __init dw_i2c_init_driver(void) 505 { 506 return platform_driver_register(&dw_i2c_driver); 507 } 508 subsys_initcall(dw_i2c_init_driver); 509 510 static void __exit dw_i2c_exit_driver(void) 511 { 512 platform_driver_unregister(&dw_i2c_driver); 513 } 514 module_exit(dw_i2c_exit_driver); 515 516 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); 517 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); 518 MODULE_LICENSE("GPL"); 519