1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Cadence USBSS and USBSSP DRD Driver. 4 * 5 * Copyright (C) 2018-2020 Cadence. 6 * Copyright (C) 2019 Texas Instruments 7 * 8 * Author: Pawel Laszczak <pawell@cadence.com> 9 * Roger Quadros <rogerq@ti.com> 10 * 11 */ 12 #include <linux/kernel.h> 13 #include <linux/interrupt.h> 14 #include <linux/delay.h> 15 #include <linux/iopoll.h> 16 #include <linux/usb/otg.h> 17 18 #include "drd.h" 19 #include "core.h" 20 21 /** 22 * cdns_set_mode - change mode of OTG Core 23 * @cdns: pointer to context structure 24 * @mode: selected mode from cdns_role 25 * 26 * Returns 0 on success otherwise negative errno 27 */ 28 static int cdns_set_mode(struct cdns *cdns, enum usb_dr_mode mode) 29 { 30 void __iomem *override_reg; 31 u32 reg; 32 33 switch (mode) { 34 case USB_DR_MODE_PERIPHERAL: 35 break; 36 case USB_DR_MODE_HOST: 37 break; 38 case USB_DR_MODE_OTG: 39 dev_dbg(cdns->dev, "Set controller to OTG mode\n"); 40 41 if (cdns->version == CDNSP_CONTROLLER_V2) 42 override_reg = &cdns->otg_cdnsp_regs->override; 43 else if (cdns->version == CDNS3_CONTROLLER_V1) 44 override_reg = &cdns->otg_v1_regs->override; 45 else 46 override_reg = &cdns->otg_v0_regs->ctrl1; 47 48 reg = readl(override_reg); 49 50 if (cdns->version != CDNS3_CONTROLLER_V0) 51 reg |= OVERRIDE_IDPULLUP; 52 else 53 reg |= OVERRIDE_IDPULLUP_V0; 54 55 writel(reg, override_reg); 56 57 if (cdns->version == CDNS3_CONTROLLER_V1) { 58 /* 59 * Enable work around feature built into the 60 * controller to address issue with RX Sensitivity 61 * est (EL_17) for USB2 PHY. The issue only occures 62 * for 0x0002450D controller version. 63 */ 64 if (cdns->phyrst_a_enable) { 65 reg = readl(&cdns->otg_v1_regs->phyrst_cfg); 66 reg |= PHYRST_CFG_PHYRST_A_ENABLE; 67 writel(reg, &cdns->otg_v1_regs->phyrst_cfg); 68 } 69 } 70 71 /* 72 * Hardware specification says: "ID_VALUE must be valid within 73 * 50ms after idpullup is set to '1" so driver must wait 74 * 50ms before reading this pin. 75 */ 76 usleep_range(50000, 60000); 77 break; 78 default: 79 dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode); 80 return -EINVAL; 81 } 82 83 return 0; 84 } 85 86 int cdns_get_id(struct cdns *cdns) 87 { 88 int id; 89 90 id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE; 91 dev_dbg(cdns->dev, "OTG ID: %d", id); 92 93 return id; 94 } 95 96 int cdns_get_vbus(struct cdns *cdns) 97 { 98 int vbus; 99 100 vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID); 101 dev_dbg(cdns->dev, "OTG VBUS: %d", vbus); 102 103 return vbus; 104 } 105 106 void cdns_clear_vbus(struct cdns *cdns) 107 { 108 u32 reg; 109 110 if (cdns->version != CDNSP_CONTROLLER_V2) 111 return; 112 113 reg = readl(&cdns->otg_cdnsp_regs->override); 114 reg |= OVERRIDE_SESS_VLD_SEL; 115 writel(reg, &cdns->otg_cdnsp_regs->override); 116 } 117 EXPORT_SYMBOL_GPL(cdns_clear_vbus); 118 119 void cdns_set_vbus(struct cdns *cdns) 120 { 121 u32 reg; 122 123 if (cdns->version != CDNSP_CONTROLLER_V2) 124 return; 125 126 reg = readl(&cdns->otg_cdnsp_regs->override); 127 reg &= ~OVERRIDE_SESS_VLD_SEL; 128 writel(reg, &cdns->otg_cdnsp_regs->override); 129 } 130 EXPORT_SYMBOL_GPL(cdns_set_vbus); 131 132 bool cdns_is_host(struct cdns *cdns) 133 { 134 if (cdns->dr_mode == USB_DR_MODE_HOST) 135 return true; 136 else if (cdns_get_id(cdns) == CDNS3_ID_HOST) 137 return true; 138 139 return false; 140 } 141 142 bool cdns_is_device(struct cdns *cdns) 143 { 144 if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) 145 return true; 146 else if (cdns->dr_mode == USB_DR_MODE_OTG) 147 if (cdns_get_id(cdns) == CDNS3_ID_PERIPHERAL) 148 return true; 149 150 return false; 151 } 152 153 /** 154 * cdns_otg_disable_irq - Disable all OTG interrupts 155 * @cdns: Pointer to controller context structure 156 */ 157 static void cdns_otg_disable_irq(struct cdns *cdns) 158 { 159 writel(0, &cdns->otg_irq_regs->ien); 160 } 161 162 /** 163 * cdns_otg_enable_irq - enable id and sess_valid interrupts 164 * @cdns: Pointer to controller context structure 165 */ 166 static void cdns_otg_enable_irq(struct cdns *cdns) 167 { 168 writel(OTGIEN_ID_CHANGE_INT | OTGIEN_VBUSVALID_RISE_INT | 169 OTGIEN_VBUSVALID_FALL_INT, &cdns->otg_irq_regs->ien); 170 } 171 172 /** 173 * cdns_drd_host_on - start host. 174 * @cdns: Pointer to controller context structure. 175 * 176 * Returns 0 on success otherwise negative errno. 177 */ 178 int cdns_drd_host_on(struct cdns *cdns) 179 { 180 u32 val, ready_bit; 181 int ret; 182 183 /* Enable host mode. */ 184 writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS, 185 &cdns->otg_regs->cmd); 186 187 if (cdns->version == CDNSP_CONTROLLER_V2) 188 ready_bit = OTGSTS_CDNSP_XHCI_READY; 189 else 190 ready_bit = OTGSTS_CDNS3_XHCI_READY; 191 192 dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n"); 193 ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val, 194 val & ready_bit, 1, 100000); 195 196 if (ret) 197 dev_err(cdns->dev, "timeout waiting for xhci_ready\n"); 198 199 phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_HOST); 200 phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_HOST); 201 return ret; 202 } 203 204 /** 205 * cdns_drd_host_off - stop host. 206 * @cdns: Pointer to controller context structure. 207 */ 208 void cdns_drd_host_off(struct cdns *cdns) 209 { 210 u32 val; 211 212 writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP | 213 OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF, 214 &cdns->otg_regs->cmd); 215 216 /* Waiting till H_IDLE state.*/ 217 readl_poll_timeout_atomic(&cdns->otg_regs->state, val, 218 !(val & OTGSTATE_HOST_STATE_MASK), 219 1, 2000000); 220 phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID); 221 phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID); 222 } 223 224 /** 225 * cdns_drd_gadget_on - start gadget. 226 * @cdns: Pointer to controller context structure. 227 * 228 * Returns 0 on success otherwise negative errno 229 */ 230 int cdns_drd_gadget_on(struct cdns *cdns) 231 { 232 u32 reg = OTGCMD_OTG_DIS; 233 u32 ready_bit; 234 int ret, val; 235 236 /* switch OTG core */ 237 writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd); 238 239 dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n"); 240 241 if (cdns->version == CDNSP_CONTROLLER_V2) 242 ready_bit = OTGSTS_CDNSP_DEV_READY; 243 else 244 ready_bit = OTGSTS_CDNS3_DEV_READY; 245 246 ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val, 247 val & ready_bit, 1, 100000); 248 if (ret) { 249 dev_err(cdns->dev, "timeout waiting for dev_ready\n"); 250 return ret; 251 } 252 253 phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_DEVICE); 254 phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_DEVICE); 255 return 0; 256 } 257 EXPORT_SYMBOL_GPL(cdns_drd_gadget_on); 258 259 /** 260 * cdns_drd_gadget_off - stop gadget. 261 * @cdns: Pointer to controller context structure. 262 */ 263 void cdns_drd_gadget_off(struct cdns *cdns) 264 { 265 u32 val; 266 267 /* 268 * Driver should wait at least 10us after disabling Device 269 * before turning-off Device (DEV_BUS_DROP). 270 */ 271 usleep_range(20, 30); 272 writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP | 273 OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF, 274 &cdns->otg_regs->cmd); 275 /* Waiting till DEV_IDLE state.*/ 276 readl_poll_timeout_atomic(&cdns->otg_regs->state, val, 277 !(val & OTGSTATE_DEV_STATE_MASK), 278 1, 2000000); 279 phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID); 280 phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID); 281 } 282 EXPORT_SYMBOL_GPL(cdns_drd_gadget_off); 283 284 /** 285 * cdns_init_otg_mode - initialize drd controller 286 * @cdns: Pointer to controller context structure 287 * 288 * Returns 0 on success otherwise negative errno 289 */ 290 static int cdns_init_otg_mode(struct cdns *cdns) 291 { 292 int ret; 293 294 cdns_otg_disable_irq(cdns); 295 /* clear all interrupts */ 296 writel(~0, &cdns->otg_irq_regs->ivect); 297 298 ret = cdns_set_mode(cdns, USB_DR_MODE_OTG); 299 if (ret) 300 return ret; 301 302 cdns_otg_enable_irq(cdns); 303 304 return 0; 305 } 306 307 /** 308 * cdns_drd_update_mode - initialize mode of operation 309 * @cdns: Pointer to controller context structure 310 * 311 * Returns 0 on success otherwise negative errno 312 */ 313 int cdns_drd_update_mode(struct cdns *cdns) 314 { 315 int ret; 316 317 switch (cdns->dr_mode) { 318 case USB_DR_MODE_PERIPHERAL: 319 ret = cdns_set_mode(cdns, USB_DR_MODE_PERIPHERAL); 320 break; 321 case USB_DR_MODE_HOST: 322 ret = cdns_set_mode(cdns, USB_DR_MODE_HOST); 323 break; 324 case USB_DR_MODE_OTG: 325 ret = cdns_init_otg_mode(cdns); 326 break; 327 default: 328 dev_err(cdns->dev, "Unsupported mode of operation %d\n", 329 cdns->dr_mode); 330 return -EINVAL; 331 } 332 333 return ret; 334 } 335 336 static irqreturn_t cdns_drd_thread_irq(int irq, void *data) 337 { 338 struct cdns *cdns = data; 339 340 cdns_hw_role_switch(cdns); 341 342 return IRQ_HANDLED; 343 } 344 345 /** 346 * cdns_drd_irq - interrupt handler for OTG events 347 * 348 * @irq: irq number for cdns core device 349 * @data: structure of cdns 350 * 351 * Returns IRQ_HANDLED or IRQ_NONE 352 */ 353 static irqreturn_t cdns_drd_irq(int irq, void *data) 354 { 355 irqreturn_t ret = IRQ_NONE; 356 struct cdns *cdns = data; 357 u32 reg; 358 359 if (cdns->dr_mode != USB_DR_MODE_OTG) 360 return IRQ_NONE; 361 362 if (cdns->in_lpm) 363 return ret; 364 365 reg = readl(&cdns->otg_irq_regs->ivect); 366 367 if (!reg) 368 return IRQ_NONE; 369 370 if (reg & OTGIEN_ID_CHANGE_INT) { 371 dev_dbg(cdns->dev, "OTG IRQ: new ID: %d\n", 372 cdns_get_id(cdns)); 373 374 ret = IRQ_WAKE_THREAD; 375 } 376 377 if (reg & (OTGIEN_VBUSVALID_RISE_INT | OTGIEN_VBUSVALID_FALL_INT)) { 378 dev_dbg(cdns->dev, "OTG IRQ: new VBUS: %d\n", 379 cdns_get_vbus(cdns)); 380 381 ret = IRQ_WAKE_THREAD; 382 } 383 384 writel(~0, &cdns->otg_irq_regs->ivect); 385 return ret; 386 } 387 388 int cdns_drd_init(struct cdns *cdns) 389 { 390 void __iomem *regs; 391 u32 state; 392 int ret; 393 394 regs = devm_ioremap_resource(cdns->dev, &cdns->otg_res); 395 if (IS_ERR(regs)) 396 return PTR_ERR(regs); 397 398 /* Detection of DRD version. Controller has been released 399 * in three versions. All are very similar and are software compatible, 400 * but they have same changes in register maps. 401 * The first register in oldest version is command register and it's 402 * read only. Driver should read 0 from it. On the other hand, in v1 403 * and v2 the first register contains device ID number which is not 404 * set to 0. Driver uses this fact to detect the proper version of 405 * controller. 406 */ 407 cdns->otg_v0_regs = regs; 408 if (!readl(&cdns->otg_v0_regs->cmd)) { 409 cdns->version = CDNS3_CONTROLLER_V0; 410 cdns->otg_v1_regs = NULL; 411 cdns->otg_cdnsp_regs = NULL; 412 cdns->otg_regs = regs; 413 cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *) 414 &cdns->otg_v0_regs->ien; 415 writel(1, &cdns->otg_v0_regs->simulate); 416 dev_dbg(cdns->dev, "DRD version v0 (%08x)\n", 417 readl(&cdns->otg_v0_regs->version)); 418 } else { 419 cdns->otg_v0_regs = NULL; 420 cdns->otg_v1_regs = regs; 421 cdns->otg_cdnsp_regs = regs; 422 423 cdns->otg_regs = (void __iomem *)&cdns->otg_v1_regs->cmd; 424 425 if (readl(&cdns->otg_cdnsp_regs->did) == OTG_CDNSP_DID) { 426 cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *) 427 &cdns->otg_cdnsp_regs->ien; 428 cdns->version = CDNSP_CONTROLLER_V2; 429 } else { 430 cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *) 431 &cdns->otg_v1_regs->ien; 432 writel(1, &cdns->otg_v1_regs->simulate); 433 cdns->version = CDNS3_CONTROLLER_V1; 434 } 435 436 dev_dbg(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n", 437 readl(&cdns->otg_v1_regs->did), 438 readl(&cdns->otg_v1_regs->rid)); 439 } 440 441 state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts)); 442 443 /* Update dr_mode according to STRAP configuration. */ 444 cdns->dr_mode = USB_DR_MODE_OTG; 445 446 if ((cdns->version == CDNSP_CONTROLLER_V2 && 447 state == OTGSTS_CDNSP_STRAP_HOST) || 448 (cdns->version != CDNSP_CONTROLLER_V2 && 449 state == OTGSTS_STRAP_HOST)) { 450 dev_dbg(cdns->dev, "Controller strapped to HOST\n"); 451 cdns->dr_mode = USB_DR_MODE_HOST; 452 } else if ((cdns->version == CDNSP_CONTROLLER_V2 && 453 state == OTGSTS_CDNSP_STRAP_GADGET) || 454 (cdns->version != CDNSP_CONTROLLER_V2 && 455 state == OTGSTS_STRAP_GADGET)) { 456 dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n"); 457 cdns->dr_mode = USB_DR_MODE_PERIPHERAL; 458 } 459 460 ret = devm_request_threaded_irq(cdns->dev, cdns->otg_irq, 461 cdns_drd_irq, 462 cdns_drd_thread_irq, 463 IRQF_SHARED, 464 dev_name(cdns->dev), cdns); 465 if (ret) { 466 dev_err(cdns->dev, "couldn't get otg_irq\n"); 467 return ret; 468 } 469 470 state = readl(&cdns->otg_regs->sts); 471 if (OTGSTS_OTG_NRDY(state)) { 472 dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n"); 473 return -ENODEV; 474 } 475 476 return 0; 477 } 478 479 int cdns_drd_exit(struct cdns *cdns) 480 { 481 cdns_otg_disable_irq(cdns); 482 483 return 0; 484 } 485 486 487 /* Indicate the cdns3 core was power lost before */ 488 bool cdns_power_is_lost(struct cdns *cdns) 489 { 490 if (cdns->version == CDNS3_CONTROLLER_V0) { 491 if (!(readl(&cdns->otg_v0_regs->simulate) & BIT(0))) 492 return true; 493 } else { 494 if (!(readl(&cdns->otg_v1_regs->simulate) & BIT(0))) 495 return true; 496 } 497 return false; 498 } 499 EXPORT_SYMBOL_GPL(cdns_power_is_lost); 500