bertos/cpu/cortex-m3/drv/usb_stm32.c

   1 /**
   2  * \file
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   5  *
   6  * Bertos is free software; you can redistribute it and/or modify
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   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
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  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  * As a special exception, you may use this file as part of a free software
  21  * library without restriction.  Specifically, if other files instantiate
  22  * templates or use macros or inline functions from this file, or you compile
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  24  * file does not by itself cause the resulting executable to be covered by
  25  * the GNU General Public License.  This exception does not however
  26  * invalidate any other reasons why the executable file might be covered by
  27  * the GNU General Public License.
  28  *
  29  * Copyright 2010 Develer S.r.l. (http://www.develer.com/)
  30  *
  31  * -->
  32  *
  33  * \brief STM32 USB driver
  34  *
  35  * \author Andrea Righi <arighi@develer.com>
  36  */
  37
  38 #include "cfg/cfg_usb.h"
  39
  40 #define LOG_LEVEL  USB_LOG_LEVEL
  41 #define LOG_FORMAT USB_LOG_FORMAT
  42
  43 #include <cfg/log.h>
  44 #include <cfg/debug.h>
  45 #include <cfg/macros.h>
  46 #include <cfg/module.h>
  47
  48 #include <cpu/irq.h>
  49 #include <cpu/power.h>
  50
  51 #include <drv/irq_cm3.h>
  52 #include <drv/gpio_stm32.h>
  53 #include <drv/clock_stm32.h>
  54 #include <drv/timer.h>
  55 #include <drv/usb.h>
  56
  57 #include <string.h> /* memcpy() */
  58
  59 #include "usb_stm32.h"
  60
  61 /* XXX: consider to move this to cfg/macros.h */
  62
  63 /* XXX: redefine this to make it usable within C expression */
  64 #define _MIN(a,b)       (((a) < (b)) ? (a) : (b))
  65
  66 /* STM32 USB registers */
  67 struct stm32_usb
  68 {
  69         reg32_t EP0R;
  70         reg32_t EP1R;
  71         reg32_t EP2R;
  72         reg32_t EP3R;
  73         reg32_t EP4R;
  74         reg32_t EP5R;
  75         reg32_t EP6R;
  76         reg32_t EP7R;
  77         reg32_t __reserved[8];
  78         reg32_t CNTR;
  79         reg32_t ISTR;
  80         reg32_t FNR;
  81         reg32_t DADDR;
  82         reg32_t BTABLE;
  83 };
  84
  85 /* Hardware registers */
  86 static struct stm32_usb *usb = (struct stm32_usb *)USB_BASE_ADDR;
  87
  88 /* Endpoint descriptors: used for handling requests to use with endpoints */
  89 static stm32_UsbEp ep_cnfg[EP_MAX_NUM];
  90 STATIC_ASSERT(EP_MAX_NUM <= EP_MAX_HW_NUM);
  91
  92 /* USB EP0 control descriptor */
  93 static const UsbEndpointDesc USB_CtrlEpDescr0 =
  94 {
  95         .bLength = sizeof(USB_CtrlEpDescr0),
  96         .bDescriptorType = USB_DT_ENDPOINT,
  97         .bEndpointAddress = USB_DIR_OUT | 0,
  98         .bmAttributes = USB_ENDPOINT_XFER_CONTROL,
  99         .wMaxPacketSize = USB_EP0_MAX_SIZE,
 100         .bInterval = 0,
 101 };
 102
 103 /* USB EP1 control descriptor */
 104 static const UsbEndpointDesc USB_CtrlEpDescr1 =
 105 {
 106         .bLength = sizeof(USB_CtrlEpDescr1),
 107         .bDescriptorType = USB_DT_ENDPOINT,
 108         .bEndpointAddress = USB_DIR_IN | 0,
 109         .bmAttributes = USB_ENDPOINT_XFER_CONTROL,
 110         .wMaxPacketSize = USB_EP0_MAX_SIZE,
 111         .bInterval = 0,
 112 };
 113
 114 /* USB setup packet */
 115 static UsbCtrlRequest setup_packet;
 116
 117 /* USB device controller: max supported interfaces */
 118 #define USB_MAX_INTERFACE       1
 119
 120 /* USB device controller features */
 121 #define STM32_UDC_FEATURE_SELFPOWERED   BV(0)
 122 #define STM32_UDC_FEATURE_REMOTE_WAKEUP BV(1)
 123
 124 /* Hardware-specific USB device controller structure */
 125 typedef struct stm32_udc
 126 {
 127         uint8_t state;
 128         uint32_t cfg_id;
 129         const UsbConfigDesc *cfg;
 130         uint32_t interfaces;
 131         uint32_t alt[USB_MAX_INTERFACE];
 132         uint32_t address;
 133         uint8_t feature;
 134 } PACKED stm32_udc_t;
 135
 136 /* Hardware-specific USB Device Controller */
 137 static stm32_udc_t udc;
 138
 139 /* Generic USB Device Controller structure */
 140 static UsbDevice *usb_dev;
 141
 142 /* USB packet memory management: list of allocated chunks */
 143 static stm32_UsbMemSlot *mem_use;
 144
 145 /* USB packet memory management: memory buffer metadata */
 146 static stm32_UsbMemSlot memory_buffer[EP_MAX_NUM];
 147
 148 /* Endpoint TX and RX buffers */
 149 /// \cond
 150 /* XXX: use the empty cond section to silent a buggy doxygen warning */
 151 static bool rx_done, tx_done;
 152 static size_t rx_size, tx_size;
 153
 154 #define EP_BUFFER_SIZE _MIN(CONFIG_USB_BUFSIZE, USB_XFER_MAX_SIZE)
 155 STATIC_ASSERT(!(EP_BUFFER_SIZE & 0x03));
 156
 157 static uint8_t ep_buffer[EP_MAX_NUM][EP_BUFFER_SIZE] ALIGNED(4);
 158 /// \endcond
 159
 160 /* Allocate a free block of the packet memory */
 161 static stm32_UsbMemSlot *usb_malloc(void)
 162 {
 163         unsigned int i;
 164
 165         for (i = 0; i < countof(memory_buffer); i++)
 166                 if (memory_buffer[i].Size == 0)
 167                         return &memory_buffer[i];
 168         return NULL;
 169 }
 170
 171 /* Release a block of the packet memory */
 172 static void usb_free(stm32_UsbMemSlot *pPntr)
 173 {
 174         pPntr->Size = 0;
 175 }
 176
 177 /* Allocate a free chunk of the packet memory (inside a block) */
 178 static bool usb_alloc_buffer(uint16_t *pOffset, uint32_t *size,
 179                             int EndPoint)
 180 {
 181         stm32_UsbMemSlot *mem = mem_use,
 182                         *memNext, *mem_useNew;
 183         uint32_t max_size = *size;
 184
 185         /*
 186          * Packet size alignment:
 187          *  - fine-granularity allocation: size alignment by 2;
 188          *  - coarse-granularity allocation: size alignment by 32.
 189          */
 190         if (max_size < 62)
 191                 max_size = ALIGN_UP(max_size, 2);
 192         else
 193                 max_size = ALIGN_UP(max_size, 32);
 194         /*
 195          * Finding free memory chunks from the allocated blocks of the USB
 196          * packet memory.
 197          */
 198         *pOffset = 0;
 199         while (mem != NULL)
 200         {
 201                 /* Offset alignment by 4 */
 202                 *pOffset = ALIGN_UP(mem->Start + mem->Size, 4);
 203                 memNext = mem->next;
 204                 if ((mem->next == NULL) ||
 205                                 (memNext->Start >=
 206                                         *pOffset + max_size))
 207                         break;
 208                 mem = mem->next;
 209         }
 210         /* Check for out-of-memory condition */
 211         if (UNLIKELY((*pOffset + max_size) >= USB_BDT_OFFSET))
 212                 return false;
 213         /*
 214          * Allocate a new memory block, next to the last allocated block.
 215          */
 216         mem_useNew = usb_malloc();
 217         if (UNLIKELY(mem_useNew == NULL))
 218                 return false;
 219         /* Insert the block to the list of allocated blocks */
 220         if (mem_use == NULL)
 221         {
 222                 mem_use = mem_useNew;
 223                 mem_use->next = NULL;
 224         }
 225         else
 226         {
 227                 mem_useNew->next = mem->next;
 228                 mem->next = mem_useNew;
 229         }
 230         /* Update block's metadata */
 231         mem_useNew->ep_addr = EndPoint;
 232         mem_useNew->Start = *pOffset;
 233         mem_useNew->Size = max_size;
 234
 235         *size = max_size;
 236
 237         return true;
 238 }
 239
 240 /* Release a chunk of the packet memory (inside a block) */
 241 static void usb_free_buffer(int EndPoint)
 242 {
 243         stm32_UsbMemSlot *mem, *memPrev = NULL;
 244         mem = mem_use;
 245
 246         while (mem != NULL)
 247         {
 248                 if (mem->ep_addr == EndPoint)
 249                 {
 250                         if (UNLIKELY(memPrev == NULL))
 251                         {
 252                                 /* Free the first element of the list */
 253                                 mem_use = mem_use->next;
 254                                 usb_free(mem);
 255                                 mem = mem_use;
 256                                 continue;
 257                         }
 258                         memPrev->next = mem->next;
 259                         usb_free(mem);
 260                 }
 261                 else
 262                         memPrev = mem;
 263                 mem = memPrev->next;
 264         }
 265 }
 266
 267 /*-------------------------------------------------------------------------*/
 268
 269 /* Connect USB controller */
 270 static void usb_connect(void)
 271 {
 272         stm32_gpioPinWrite((struct stm32_gpio *)GPIOC_BASE, 1 << 11, 0);
 273 }
 274
 275 /* Set USB device address */
 276 static void usb_set_address(uint32_t addr)
 277 {
 278         usb->DADDR = addr | 0x80;
 279 }
 280
 281 /* Suspend USB controller */
 282 static void usb_suspend(void)
 283 {
 284         usb->CNTR |= bmFSUSP | bmLPMODE;
 285 }
 286
 287 /* Resume USB controller */
 288 static void usb_resume(void)
 289 {
 290         uint32_t line_status;
 291
 292         line_status = usb->FNR & 0xc000;
 293         if (!line_status)
 294                 return;
 295         /* check for noise and eventually return to sleep */
 296         if (line_status == 0xc000)
 297                 usb_suspend();
 298         else
 299                 usb->CNTR &= ~(bmFSUSP | bmLPMODE);
 300 }
 301
 302 /* Convert logical EP address to physical EP address */
 303 static int usb_ep_logical_to_hw(uint8_t ep_addr)
 304 {
 305         int addr = (ep_addr & 0x0f) << 1;
 306         return (ep_addr & 0x80) ? addr + 1 : addr;
 307 }
 308
 309 /* Set EP address */
 310 static void ep_ctrl_set_ea(reg32_t *reg, uint32_t val)
 311 {
 312         val &= 0x0f;
 313         val |= *reg & 0x0700;
 314         val |= USB_CTRL_CLEAR_ONLY_MASK;
 315         *reg = val;
 316 }
 317
 318 /* Get EP IN status */
 319 static uint32_t ep_ctrl_get_stat_tx(reg32_t *reg)
 320 {
 321         return (*reg & (0x3UL << 4)) >> 4;
 322 }
 323
 324 /* Set EP IN state */
 325 static void ep_ctrl_set_stat_tx(reg32_t *reg, stm32_UsbEpState val)
 326 {
 327         uint32_t state;
 328         int i;
 329
 330         /*
 331          * The EP can change state between read and write operations from VALID
 332          * to NAK and result of set operation will be invalid.
 333          */
 334         for (i = 0; i < 2; i++)
 335         {
 336                 if (ep_ctrl_get_stat_tx(reg) == val)
 337                         return;
 338                 state = val;
 339                 state <<= 4;
 340                 state ^= *reg;
 341                 state |= USB_CTRL_CLEAR_ONLY_MASK;
 342                 /* Clear the toggle bits without STAT_TX (4,5) */
 343                 state &= ~0x7040;
 344                 *reg = state;
 345         }
 346 }
 347
 348 /* Set EP DTOG_TX bit (IN) */
 349 static void ep_ctrl_set_dtog_tx(reg32_t *reg, uint32_t val)
 350 {
 351         val = val ? (*reg ^ (1UL << 6)) : *reg;
 352         /* Clear the toggle bits without DTOG_TX (6) */
 353         val &= ~0x7030;
 354         val |= USB_CTRL_CLEAR_ONLY_MASK;
 355         *reg = val;
 356 }
 357
 358 /* Clear EP CTR_TX bit (IN) */
 359 static void ep_ctrl_clr_ctr_tx(reg32_t *reg)
 360 {
 361         uint32_t val = *reg;
 362
 363         val &= ~(USB_CTRL_TOGGLE_MASK | 1UL << 7);
 364         /* Set RX_CTR */
 365         val |= 1UL << 15;
 366         *reg = val;
 367 }
 368
 369 /* Clear EP CTR_RX bit (OUT) */
 370 static void ep_ctrl_clr_ctr_rx(reg32_t *reg)
 371 {
 372         uint32_t val = *reg;
 373         val &= ~(USB_CTRL_TOGGLE_MASK | 1UL << 15);
 374         /* Set TX_CTR */
 375         val |= 1UL << 7;
 376         *reg = val;
 377 }
 378
 379 /* Set EP KIND bit */
 380 static void ep_ctrl_set_ep_kind(reg32_t *reg, uint32_t val)
 381 {
 382         val = val ? (1UL << 8) : 0;
 383         val |= *reg & ~(USB_CTRL_TOGGLE_MASK | (1UL << 8));
 384         val |= USB_CTRL_CLEAR_ONLY_MASK;
 385         *reg = val;
 386 }
 387
 388 /* Set EP type */
 389 static int ep_ctrl_set_ep_type(reg32_t *reg, uint8_t val)
 390 {
 391         uint32_t type;
 392
 393         if (UNLIKELY(val >= EP_TYPE_MAX))
 394         {
 395                 ASSERT(0);
 396                 return USB_INVAL_ERROR;
 397         }
 398         type = val;
 399         type <<= 9;
 400         type |= *reg & ~(USB_CTRL_TOGGLE_MASK | (0x3UL << 9));
 401         type |= USB_CTRL_CLEAR_ONLY_MASK;
 402         *reg = type;
 403
 404         return USB_OK;
 405 }
 406
 407 /* Get EP STAT_RX (OUT) */
 408 static uint32_t ep_ctrl_get_stat_rx(reg32_t *reg)
 409 {
 410         uint32_t val = *reg & (0x3UL << 12);
 411         return val >> 12;
 412 }
 413
 414 /* Set EP STAT_RX (OUT) */
 415 static void ep_ctrl_set_stat_rx(reg32_t *reg, stm32_UsbEpState val)
 416 {
 417         uint32_t state;
 418         int i;
 419
 420         /*
 421          * The EP can change state between read and write operations from VALID
 422          * to NAK and result of set operation will be invalid.
 423          */
 424         for (i = 0; i < 2; i++)
 425         {
 426                 if (ep_ctrl_get_stat_rx(reg) == val)
 427                         return;
 428                 state = val;
 429                 state <<= 12;
 430                 state ^= *reg;
 431                 state |= USB_CTRL_CLEAR_ONLY_MASK;
 432                 /* Clear the toggle bits without STAT_RX (12,13) */
 433                 state &= ~0x4070;
 434                 *reg = state;
 435         }
 436 }
 437
 438 /* Set DTOG_RX bit */
 439 static void ep_ctrl_set_dtog_rx(reg32_t *reg, uint32_t val)
 440 {
 441         val = val ? (*reg ^ (1UL << 14)) : *reg;
 442         /* Clear the toggle bits without DTOG_RX (14) */
 443         val &= ~0x3070;
 444         val |= USB_CTRL_CLEAR_ONLY_MASK;
 445         *reg = val;
 446 }
 447
 448 /* Get EP SETUP bit */
 449 static uint32_t ep_ctrl_get_setup(reg32_t *reg)
 450 {
 451         uint32_t val = *reg & (1UL << 11);
 452         return val ? 1 : 0;
 453 }
 454
 455 /* Core endpoint I/O function */
 456 static void __usb_ep_io(int EP)
 457 {
 458         ssize_t Count, CountHold, Offset;
 459         uint32_t *pDst, *pSrc, Data;
 460         stm32_UsbEp *epd = &ep_cnfg[EP];
 461
 462         if (UNLIKELY(epd->hw == NULL))
 463         {
 464                 LOG_ERR("%s: invalid endpoint (EP%d-%s)\n",
 465                                 __func__,
 466                                 EP >> 1,
 467                                 (EP & 0x01) ? "IN" : "OUT");
 468                 ASSERT(0);
 469                 return;
 470         }
 471         if (epd->status != BEGIN_SERVICED && epd->status != NO_SERVICED)
 472                 return;
 473
 474         if (EP & 0x01)
 475         {
 476                 /* EP IN */
 477                 Count = epd->size - epd->offset;
 478                 while (epd->avail_data)
 479                 {
 480                         if (!Count && !(epd->flags & STM32_USB_EP_ZERO_PACKET))
 481                                 break;
 482
 483                         /* Set Status */
 484                         epd->status = BEGIN_SERVICED;
 485                         /* Get data size */
 486                         if ((epd->flags & STM32_USB_EP_ZERO_PACKET) &&
 487                                         (Count == epd->max_size))
 488                                 epd->flags |= STM32_USB_EP_ZERO_PACKET |
 489                                                 STM32_USB_EP_ZERO_POSSIBLE;
 490
 491                         CountHold = Count = MIN(Count, epd->max_size);
 492                         if (!Count)
 493                                 epd->flags |= STM32_USB_EP_ZERO_PACKET;
 494                         Offset = epd->offset;
 495                         epd->offset += Count;
 496                         switch (epd->type)
 497                         {
 498                         case USB_ENDPOINT_XFER_CONTROL:
 499                         case USB_ENDPOINT_XFER_INT:
 500                                 pDst = (uint32_t *)USB_MEM_ADDR(EP_DTB_READ(EP >> 1, ADDR_TX_OFFSET));
 501                                 break;
 502                         case USB_ENDPOINT_XFER_BULK:
 503                                 pDst = (uint32_t *)USB_MEM_ADDR(EP_DTB_READ(EP >> 1, ADDR_TX_OFFSET));
 504                                 break;
 505                         case USB_ENDPOINT_XFER_ISOC:
 506                                 LOG_ERR("%s: isochronous transfer not supported\n",
 507                                         __func__);
 508                                 /* Fallback to default */
 509                         default:
 510                                 ASSERT(0);
 511                                 return;
 512                         }
 513
 514                         /* Write data to packet memory buffer */
 515                         while (Count)
 516                         {
 517                                 Data = *(epd->write_buffer + Offset++);
 518                                 if (--Count)
 519                                 {
 520                                         Data |= (uint32_t)(*(epd->write_buffer + Offset++)) << 8;
 521                                         --Count;
 522                                 }
 523                                 *pDst++ = Data;
 524                         }
 525
 526                         EP_DTB_WRITE(EP >> 1, COUNT_TX_OFFSET, CountHold);
 527                         ep_ctrl_set_stat_tx(epd->hw, EP_VALID);
 528
 529                         --ep_cnfg[EP].avail_data;
 530                         Count = epd->size - epd->offset;
 531                 }
 532                 if (!Count && !(epd->flags & STM32_USB_EP_ZERO_PACKET))
 533                 {
 534                         epd->status = COMPLETE;
 535                         /* call callback function */
 536                         if (epd->complete)
 537                                 epd->complete(EP);
 538                 }
 539         }
 540         else
 541         {
 542                 /* EP OUT */
 543                 while (epd->avail_data)
 544                 {
 545                         /* Get data size and buffer pointer */
 546                         switch (epd->type)
 547                         {
 548                         case USB_ENDPOINT_XFER_CONTROL:
 549                         case USB_ENDPOINT_XFER_INT:
 550                                 /* Get received bytes number */
 551                                 Count = EP_DTB_READ(EP >> 1, COUNT_RX_OFFSET) & 0x3FF;
 552                                 /* Get address of the USB packet buffer for corresponding EP */
 553                                 pSrc = (uint32_t *)USB_MEM_ADDR(EP_DTB_READ(EP >> 1, ADDR_RX_OFFSET));
 554                                 break;
 555                         case USB_ENDPOINT_XFER_BULK:
 556                                 /* Get received bytes number */
 557                                 Count = EP_DTB_READ(EP >> 1, COUNT_RX_OFFSET) & 0x3FF;
 558                                 /* Get address of the USB packet buffer for corresponding EP */
 559                                 pSrc = (uint32_t *)USB_MEM_ADDR(EP_DTB_READ(EP >> 1, ADDR_RX_OFFSET));
 560                                 break;
 561                         case USB_ENDPOINT_XFER_ISOC:
 562                                 LOG_ERR("%s: isochronous transfer not supported\n",
 563                                         __func__);
 564                                 /* Fallback to default */
 565                         default:
 566                                 ASSERT(0);
 567                                 return;
 568                         }
 569
 570                         if (Count > (epd->size - epd->offset))
 571                         {
 572                                 epd->status = BUFFER_OVERRUN;
 573                                 epd->size = ep_cnfg[EP].offset;
 574                                 break;
 575                         }
 576                         else if (Count < ep_cnfg[EP].max_size)
 577                         {
 578                                 epd->status = BUFFER_UNDERRUN;
 579                                 epd->size = ep_cnfg[EP].offset + Count;
 580                         }
 581                         else
 582                                 epd->status = BEGIN_SERVICED;
 583
 584                         Offset = epd->offset;
 585                         epd->offset += Count;
 586
 587                         /* Read data from packet memory buffer */
 588                         while (Count)
 589                         {
 590                                 Data = *pSrc++;
 591                                 *(epd->read_buffer + Offset++) = Data;
 592                                 if (--Count)
 593                                 {
 594                                         Data >>= 8;
 595                                         *(epd->read_buffer + Offset++) = Data;
 596                                         --Count;
 597                                 }
 598                         }
 599
 600                         ep_ctrl_set_stat_rx(epd->hw, EP_VALID);
 601
 602                         --ep_cnfg[EP].avail_data;
 603
 604                         if (*epd->hw & (1UL << 11))
 605                         {
 606                                 ep_cnfg[EP].status = SETUP_OVERWRITE;
 607                                 return;
 608                         }
 609                         if (!(Count = (epd->size - epd->offset)))
 610                         {
 611                                 epd->status = COMPLETE;
 612                                 break;
 613                         }
 614                 }
 615                 if (epd->status != BEGIN_SERVICED && epd->status != NO_SERVICED)
 616                 {
 617                         /* call callback function */
 618                         if (epd->complete)
 619                                 epd->complete(EP);
 620                 }
 621         }
 622 }
 623
 624 /*
 625  * Return the lower value from Host expected size and size and set a flag
 626  * STM32_USB_EP_ZERO_POSSIBLE when size is lower that host expected size.
 627  */
 628 static size_t usb_size(size_t size, size_t host_size)
 629 {
 630         if (size < host_size)
 631         {
 632                 ep_cnfg[CTRL_ENP_IN].flags |= STM32_USB_EP_ZERO_POSSIBLE;
 633                 return size;
 634         }
 635         return host_size;
 636 }
 637
 638 /* Configure an EP descriptor before performing a I/O operation */
 639 #define USB_EP_IO(__EP, __op, __buf, __size, __complete)                \
 640 ({                                                                      \
 641         cpu_flags_t flags;                                              \
 642         stm32_UsbIoStatus ret;                                  \
 643                                                                         \
 644         /* Fill EP descriptor */                                        \
 645         IRQ_SAVE_DISABLE(flags);                                        \
 646         if (__size < 0)                                                 \
 647         {                                                               \
 648                 ep_cnfg[__EP].status = NOT_READY;                       \
 649                 ep_cnfg[__EP].complete = NULL;                          \
 650                 ret = NOT_READY;                                        \
 651                 goto out;                                               \
 652         }                                                               \
 653         if (ep_cnfg[__EP].status == BEGIN_SERVICED)                     \
 654         {                                                               \
 655                 ret = NOT_READY;                                        \
 656                 goto out;                                               \
 657         }                                                               \
 658         /*                                                              \
 659          * NOTE: the write_buffer and read_buffer are actually the      \
 660          * same location in memory (it's a union).                      \
 661          *                                                              \
 662          * We have to do this trick to silent a build warning by        \
 663          * casting the I/O buffer to (void *) or (const void *).        \
 664          */                                                             \
 665         ep_cnfg[__EP].__op ## _buffer = __buf;                          \
 666         ep_cnfg[__EP].offset = 0;                                       \
 667         ep_cnfg[__EP].size = __size;                                    \
 668         ep_cnfg[__EP].complete = __complete;                            \
 669         if (!size)                                                      \
 670                 ep_cnfg[__EP].flags = STM32_USB_EP_ZERO_PACKET;         \
 671         else                                                            \
 672                 ep_cnfg[__EP].flags = 0;                                \
 673         ep_cnfg[__EP].status = NO_SERVICED;                             \
 674                                                                         \
 675         /* Perform the I/O operation */                                 \
 676         __usb_ep_io(__EP);                                              \
 677                                                                         \
 678         ret = ep_cnfg[__EP].status;                                     \
 679 out:                                                                    \
 680         IRQ_RESTORE(flags);                                             \
 681         ret;                                                            \
 682 })
 683
 684 /* Configure and endponint and perform a read operation */
 685 static stm32_UsbIoStatus
 686 __usb_ep_read(int ep, void *buffer, ssize_t size, void (*complete)(int))
 687 {
 688         if (UNLIKELY((ep >= EP_MAX_NUM) || (ep & 0x01)))
 689         {
 690                 LOG_ERR("%s: invalid EP number %d\n", __func__, ep);
 691                 ASSERT(0);
 692                 return STALLED;
 693         }
 694         if (UNLIKELY((size_t)buffer & 0x03))
 695         {
 696                 LOG_ERR("%s: unaligned buffer @ %p\n", __func__, buffer);
 697                 ASSERT(0);
 698                 return STALLED;
 699         }
 700         return USB_EP_IO(ep, read, buffer, size, complete);
 701 }
 702
 703 /* Configure and endponint and perform a write operation */
 704 static stm32_UsbIoStatus
 705 __usb_ep_write(int ep, const void *buffer, ssize_t size, void (*complete)(int))
 706 {
 707         if (UNLIKELY((ep >= EP_MAX_NUM) || !(ep & 0x01)))
 708         {
 709                 LOG_ERR("%s: invalid EP number %d\n", __func__, ep);
 710                 ASSERT(0);
 711                 return STALLED;
 712         }
 713         if (UNLIKELY((size_t)buffer & 0x03))
 714         {
 715                 LOG_ERR("%s: unaligned buffer @ %p\n", __func__, buffer);
 716                 ASSERT(0);
 717                 return STALLED;
 718         }
 719         return USB_EP_IO(ep, write, buffer, size, complete);
 720 }
 721
 722 static void usb_ep_low_level_config(int ep, uint16_t offset, uint16_t size)
 723 {
 724         stm32_UsbEp *epc = &ep_cnfg[ep];
 725
 726         /* IN EP */
 727         if (ep & 0x01)
 728         {
 729                 /* Disable EP */
 730                 ep_ctrl_set_stat_tx(epc->hw, EP_DISABLED);
 731                 /* Clear Tx toggle */
 732                 ep_ctrl_set_dtog_tx(epc->hw, 0);
 733                 /* Clear Correct Transfer for transmission flag */
 734                 ep_ctrl_clr_ctr_tx(epc->hw);
 735
 736                 /* Update EP description table */
 737                 EP_DTB_WRITE(ep >> 1, ADDR_TX_OFFSET, offset);
 738                 EP_DTB_WRITE(ep >> 1, COUNT_TX_OFFSET, 0);
 739         }
 740         /* OUT EP */
 741         else
 742         {
 743                 uint16_t rx_count = 0;
 744
 745                 /* Disable EP */
 746                 ep_ctrl_set_stat_rx(epc->hw, EP_DISABLED);
 747                 /* Clear Rx toggle */
 748                 ep_ctrl_set_dtog_rx(epc->hw, 0);
 749                 /* Clear Correct Transfer for reception flag */
 750                 ep_ctrl_clr_ctr_rx(epc->hw);
 751                 /* Descriptor block size field */
 752                 rx_count |= (size > 62) << 15;
 753                 /* Descriptor number of blocks field */
 754                 rx_count |= (((size > 62) ?  (size >> 5) - 1 : size >> 1) &
 755                                 0x1f) << 10;
 756                 /* Update EP description table */
 757                 EP_DTB_WRITE(ep >> 1, ADDR_RX_OFFSET, offset);
 758                 EP_DTB_WRITE(ep >> 1, COUNT_RX_OFFSET, rx_count);
 759         }
 760 }
 761
 762 /* Enable/Disable an endpoint */
 763 static int usb_ep_configure(const UsbEndpointDesc *epd, bool enable)
 764 {
 765         int EP;
 766         stm32_UsbEp *ep_hw;
 767         reg32_t *hw;
 768         uint16_t Offset;
 769         uint32_t size;
 770
 771         EP = usb_ep_logical_to_hw(epd->bEndpointAddress);
 772         ep_hw = &ep_cnfg[EP];
 773
 774         if (enable)
 775         {
 776                 /*
 777                  * Allocate packet memory for EP buffer/s calculate actual size
 778                  * only for the OUT EPs.
 779                  */
 780                 size = epd->wMaxPacketSize;
 781                 if (!usb_alloc_buffer(&Offset, &size, EP))
 782                         return -USB_MEMORY_FULL;
 783
 784                 /* Set EP status */
 785                 ep_hw->status  = NOT_READY;
 786                 /* Init EP flags */
 787                 ep_hw->flags = 0;
 788
 789                 /* Set endpoint type */
 790                 ep_hw->type = usb_endpointType(epd);
 791                 /* Init EP max packet size */
 792                 ep_hw->max_size = epd->wMaxPacketSize;
 793
 794                 if (EP & 0x01)
 795                         ep_hw->avail_data = 1;
 796                 else
 797                         ep_hw->avail_data = 0;
 798                 hw = (reg32_t *)&usb->EP0R;
 799                 hw += EP >> 1;
 800
 801                 /* Set Ep Address */
 802                 ep_ctrl_set_ea(hw, EP >> 1);
 803                 ep_hw->hw = hw;
 804                 LOG_INFO("%s: EP%d-%s configured\n",
 805                                 __func__, EP >> 1, EP & 1 ? "IN" : "OUT");
 806
 807                 /* Low-level endpoint configuration */
 808                 usb_ep_low_level_config(EP, Offset, size);
 809
 810                 /* Set EP Kind & enable */
 811                 switch (ep_hw->type)
 812                 {
 813                 case USB_ENDPOINT_XFER_CONTROL:
 814                         LOG_INFO("EP%d: CONTROL IN\n", EP >> 1);
 815                         ep_ctrl_set_ep_type(hw, EP_CTRL);
 816                         ep_ctrl_set_ep_kind(hw, 0);
 817                         break;
 818                 case USB_ENDPOINT_XFER_INT:
 819                         LOG_INFO("EP%d: INTERRUPT IN\n", EP >> 1);
 820                         ep_ctrl_set_ep_type(hw, EP_INTERRUPT);
 821                         ep_ctrl_set_ep_kind(hw, 0);
 822                         break;
 823                 case USB_ENDPOINT_XFER_BULK:
 824                         LOG_INFO("EP%d: BULK IN\n", EP >> 1);
 825                         ep_ctrl_set_ep_type(hw, EP_BULK);
 826                         ep_ctrl_set_ep_kind(hw, 0);
 827                         break;
 828                 case USB_ENDPOINT_XFER_ISOC:
 829                         LOG_ERR("EP%d: ISOCHRONOUS IN: not supported\n", EP >> 1);
 830                         /* Fallback to default */
 831                 default:
 832                         ASSERT(0);
 833                         return -USB_NODEV_ERROR;
 834                 }
 835                 if (EP & 0x01)
 836                 {
 837                         /* Enable EP */
 838                         ep_ctrl_set_stat_tx(hw, EP_NAK);
 839                         /* Clear Correct Transfer for transmission flag */
 840                         ep_ctrl_clr_ctr_tx(hw);
 841                 }
 842                 else
 843                 {
 844                         /* Enable EP */
 845                         ep_ctrl_set_stat_rx(hw, EP_VALID);
 846                 }
 847         }
 848         else if (ep_cnfg[EP].hw)
 849         {
 850                 hw = (reg32_t *)&usb->EP0R;
 851                 hw += EP >> 1;
 852
 853                 /* IN EP */
 854                 if (EP & 0x01)
 855                 {
 856                         /* Disable IN EP */
 857                         ep_ctrl_set_stat_tx(hw, EP_DISABLED);
 858                         /* Clear Correct Transfer for reception flag */
 859                         ep_ctrl_clr_ctr_tx(hw);
 860                 }
 861                 /* OUT EP */
 862                 else
 863                 {
 864                         /* Disable OUT EP */
 865                         ep_ctrl_set_stat_rx(hw, EP_DISABLED);
 866                         /* Clear Correct Transfer for reception flag */
 867                         ep_ctrl_clr_ctr_rx(hw);
 868                 }
 869                 /* Release buffer */
 870                 usb_free_buffer(EP);
 871                 ep_cnfg[EP].hw = NULL;
 872         }
 873         return 0;
 874 }
 875
 876 /* Get EP stall/unstall */
 877 static int usb_ep_get_stall(int EP, bool *pStall)
 878 {
 879         if (ep_cnfg[EP].hw == NULL)
 880                 return -USB_NODEV_ERROR;
 881
 882         *pStall = (EP & 0x01) ?
 883                 (ep_ctrl_get_stat_tx(ep_cnfg[EP].hw) == EP_STALL):  /* IN EP  */
 884                 (ep_ctrl_get_stat_rx(ep_cnfg[EP].hw) == EP_STALL);  /* OUT EP */
 885
 886         return USB_OK;
 887 }
 888
 889 /* Set EP stall/unstall */
 890 static int usb_ep_set_stall(int EP, bool Stall)
 891 {
 892         if (ep_cnfg[EP].hw == NULL)
 893                 return -USB_NODEV_ERROR;
 894
 895         if (Stall)
 896         {
 897                 ep_cnfg[EP].status = STALLED;
 898                 if (EP & 0x01)
 899                 {
 900                         /* IN EP */
 901                         ep_ctrl_set_stat_tx(ep_cnfg[EP].hw, EP_STALL);
 902                         ep_cnfg[EP].avail_data = 1;
 903                 }
 904                 else
 905                 {
 906                         /* OUT EP */
 907                         ep_ctrl_set_stat_rx(ep_cnfg[EP].hw, EP_STALL);
 908                         ep_cnfg[EP].avail_data = 0;
 909                 }
 910         }
 911         else
 912         {
 913                 ep_cnfg[EP].status = NOT_READY;
 914                 if(EP & 0x01)
 915                 {
 916                         /* IN EP */
 917                         ep_cnfg[EP].avail_data = 1;
 918                         /* reset Data Toggle bit */
 919                         ep_ctrl_set_dtog_tx(ep_cnfg[EP].hw, 0);
 920                         ep_ctrl_set_stat_tx(ep_cnfg[EP].hw, EP_NAK);
 921                 }
 922                 else
 923                 {
 924                         /* OUT EP */
 925                         ep_cnfg[EP].avail_data = 0;
 926                         /* reset Data Toggle bit */
 927                         ep_ctrl_set_dtog_rx(ep_cnfg[EP].hw, 0);
 928                         ep_ctrl_set_stat_rx(ep_cnfg[EP].hw, EP_VALID);
 929                 }
 930         }
 931         return USB_OK;
 932 }
 933
 934 /* Stall both directions of the control EP */
 935 static void usb_ep_set_stall_ctrl(void)
 936 {
 937         ep_cnfg[CTRL_ENP_IN].avail_data = 1;
 938         ep_cnfg[CTRL_ENP_IN].status = STALLED;
 939         ep_cnfg[CTRL_ENP_OUT].avail_data = 0;
 940         ep_cnfg[CTRL_ENP_OUT].status = STALLED;
 941
 942         usb_ep_set_stall(CTRL_ENP_IN, true);
 943         usb_ep_set_stall(CTRL_ENP_OUT, true);
 944 }
 945
 946 /*
 947  * Find the position of an interface descriptor inside the configuration
 948  * descriptor.
 949  */
 950 static int usb_find_interface(uint32_t num, uint32_t alt)
 951 {
 952         const UsbInterfaceDesc *id;
 953         int i;
 954
 955         for (i = 0; ; i++)
 956         {
 957                 /* TODO: support more than one configuration per device */
 958                 id = (const UsbInterfaceDesc *)usb_dev->config[i];
 959                 if (id == NULL)
 960                         break;
 961                 if (id->bDescriptorType != USB_DT_INTERFACE)
 962                         continue;
 963                 if ((id->bInterfaceNumber == num) &&
 964                                 (id->bAlternateSetting == alt))
 965                         return i;
 966         }
 967         return -USB_NODEV_ERROR;
 968 }
 969
 970 /*
 971  * Configure/deconfigure EPs of a certain interface.
 972  */
 973 static void
 974 usb_configure_ep_interface(unsigned int num, unsigned int alt, bool enable)
 975 {
 976         const UsbEndpointDesc *epd;
 977         int i, start;
 978
 979         /*
 980          * Find the position of the interface descriptor (inside the
 981          * configuration descriptor).
 982          */
 983         start = usb_find_interface(num, alt);
 984         if (start < 0)
 985         {
 986                 LOG_ERR("%s: interface (%u,%u) not found\n",
 987                         __func__, num, alt);
 988                 return;
 989         }
 990         /*
 991          * Cycle over endpoint descriptors.
 992          *
 993          * NOTE: the first endpoint descriptor is placed next to the interface
 994          * descriptor, so we need to add +1 to the position of the interface
 995          * descriptor to find it.
 996          */
 997         for (i = start + 1; ; i++)
 998         {
 999                 epd = (const UsbEndpointDesc *)usb_dev->config[i];
1000                 if ((epd == NULL) || (epd->bDescriptorType == USB_DT_INTERFACE))
1001                         break;
1002                 if (epd->bDescriptorType != USB_DT_ENDPOINT)
1003                         continue;
1004                 if (UNLIKELY(usb_ep_configure(epd, enable) < 0))
1005                 {
1006                         LOG_ERR("%s: out of memory, can't initialize EP\n",
1007                                 __func__);
1008                         return;
1009                 }
1010         }
1011 }
1012
1013 /* Set device state */
1014 static void usb_set_device_state(int state)
1015 {
1016         unsigned int i;
1017
1018         LOG_INFO("%s: new state %d\n", __func__, state);
1019
1020         if (udc.state == USB_STATE_CONFIGURED)
1021         {
1022                 /* Deconfigure device */
1023                 for (i = 0; i < udc.interfaces; ++i)
1024                         usb_configure_ep_interface(i,
1025                                 udc.alt[i], false);
1026         }
1027         switch (state)
1028         {
1029         case USB_STATE_ATTACHED:
1030         case USB_STATE_POWERED:
1031         case USB_STATE_DEFAULT:
1032                 usb_set_address(0);
1033                 usb_dev->configured = false;
1034                 udc.address = udc.cfg_id = 0;
1035                 break;
1036         case USB_STATE_ADDRESS:
1037                 udc.cfg_id = 0;
1038                 break;
1039         case USB_STATE_CONFIGURED:
1040                 /* Configure device */
1041                 for (i = 0; i < udc.interfaces; ++i)
1042                         usb_configure_ep_interface(i,
1043                                 udc.alt[i], true);
1044                 break;
1045         default:
1046                 /* Unknown state: disconnected or connection in progress */
1047                 usb_dev->configured = false;
1048                 udc.address = 0;
1049                 udc.cfg_id = 0;
1050                 break;
1051         }
1052         udc.state = state;
1053 }
1054
1055 /* Setup packet: set address status phase end handler */
1056 static void usb_add_status_handler_end(UNUSED_ARG(int, EP))
1057 {
1058         uint16_t w_value;
1059
1060         w_value = usb_le16_to_cpu(setup_packet.wValue);
1061         udc.address = w_value & 0xff;
1062         usb_set_address(udc.address);
1063
1064         if (udc.address)
1065                 usb_set_device_state(USB_STATE_ADDRESS);
1066         else
1067                 usb_set_device_state(USB_STATE_DEFAULT);
1068
1069         __usb_ep_write(CTRL_ENP_IN, NULL, -1, NULL);
1070         __usb_ep_read(CTRL_ENP_OUT, NULL, -1, NULL);
1071 }
1072
1073 /* Prepare status phase */
1074 static void usb_status_phase(bool in)
1075 {
1076         if (in)
1077                 __usb_ep_write(CTRL_ENP_IN, NULL, 0, NULL);
1078 }
1079
1080 /* Setup packet: status phase end handler */
1081 static void usb_status_handler_end(UNUSED_ARG(int, EP))
1082 {
1083         __usb_ep_write(CTRL_ENP_IN, NULL, -1, NULL);
1084         __usb_ep_read(CTRL_ENP_OUT, NULL, -1, NULL);
1085 }
1086
1087 /* Address status handler */
1088 static void usb_status_handler(UNUSED_ARG(int, EP))
1089 {
1090         if (setup_packet.mRequestType & USB_DIR_IN)
1091         {
1092                 usb_status_phase(false);
1093                 ep_cnfg[CTRL_ENP_OUT].complete = usb_status_handler_end;
1094         }
1095         else
1096         {
1097                 usb_status_phase(true);
1098                 ep_cnfg[CTRL_ENP_IN].complete =
1099                         (setup_packet.bRequest == USB_REQ_SET_ADDRESS) ?
1100                                 usb_add_status_handler_end :
1101                                 usb_status_handler_end;
1102         }
1103 }
1104
1105 static void usb_endpointRead_complete(int ep)
1106 {
1107         if (UNLIKELY(ep >= EP_MAX_NUM))
1108         {
1109                 ASSERT(0);
1110                 return;
1111         }
1112         ASSERT(!(ep & 0x01));
1113
1114         rx_done = true;
1115         rx_size = ep_cnfg[ep].size;
1116 }
1117
1118 ssize_t usb_endpointRead(int ep, void *buffer, ssize_t size)
1119 {
1120         int ep_num = usb_ep_logical_to_hw(ep);
1121         ssize_t max_size = sizeof(ep_buffer[ep_num]);
1122
1123         /* Non-blocking read for EP0 */
1124         if (ep_num == CTRL_ENP_OUT)
1125         {
1126                 size = usb_size(size, usb_le16_to_cpu(setup_packet.wLength));
1127                 if (UNLIKELY(size > max_size))
1128                 {
1129                         LOG_ERR("%s: ep_buffer exceeded, try to enlarge CONFIG_USB_BUFSIZE\n",
1130                                         __func__);
1131                         ASSERT(0);
1132                         return -USB_BUF_OVERFLOW;
1133                 }
1134                 if (!size)
1135                         usb_status_handler(ep_num);
1136                 else
1137                 {
1138                         __usb_ep_read(ep_num, ep_buffer[ep_num], size,
1139                                         usb_status_handler);
1140                         memcpy(buffer, ep_buffer[ep_num], size);
1141                 }
1142                 return size;
1143         }
1144         if (UNLIKELY(!size))
1145                 return 0;
1146         size = MIN(size, max_size);
1147         rx_done = false;
1148         rx_size = 0;
1149
1150         /* Blocking read */
1151         __usb_ep_read(ep_num, ep_buffer[ep_num], size,
1152                                 usb_endpointRead_complete);
1153         while (!rx_done)
1154                 cpu_relax();
1155         memcpy(buffer, ep_buffer[ep_num], rx_size);
1156
1157         return rx_size;
1158 }
1159
1160 static void usb_endpointWrite_complete(int ep)
1161 {
1162         if (UNLIKELY(ep >= EP_MAX_NUM))
1163         {
1164                 ASSERT(0);
1165                 return;
1166         }
1167         ASSERT(ep & 0x01);
1168
1169         tx_done = true;
1170         tx_size = ep_cnfg[ep].size;
1171 }
1172
1173 ssize_t usb_endpointWrite(int ep, const void *buffer, ssize_t size)
1174 {
1175         int ep_num = usb_ep_logical_to_hw(ep);
1176         ssize_t max_size = sizeof(ep_buffer[ep_num]);
1177
1178         /* Non-blocking write for EP0 */
1179         if (ep_num == CTRL_ENP_IN)
1180         {
1181                 size = usb_size(size, usb_le16_to_cpu(setup_packet.wLength));
1182                 if (UNLIKELY(size > max_size))
1183                 {
1184                         LOG_ERR("%s: ep_buffer exceeded, try to enlarge CONFIG_USB_BUFSIZE\n",
1185                                         __func__);
1186                         ASSERT(0);
1187                         return -USB_BUF_OVERFLOW;
1188                 }
1189                 if (!size)
1190                         usb_status_handler(ep_num);
1191                 else
1192                 {
1193                         memcpy(ep_buffer[ep_num], buffer, size);
1194                         __usb_ep_write(ep_num, ep_buffer[ep_num], size,
1195                                         usb_status_handler);
1196                 }
1197                 return size;
1198         }
1199         if (UNLIKELY(!size))
1200                 return 0;
1201         size = MIN(size, max_size);
1202         tx_done = false;
1203         tx_size = 0;
1204
1205         /* Blocking write */
1206         memcpy(ep_buffer[ep_num], buffer, size);
1207         __usb_ep_write(ep_num, ep_buffer[ep_num], size,
1208                                 usb_endpointWrite_complete);
1209         while (!tx_done)
1210                 cpu_relax();
1211
1212         return tx_size;
1213 }
1214
1215 /* Global variable to handle the following non-blocking I/O operations */
1216 static uint32_t InData;
1217
1218 /* Get device status */
1219 static int usb_send_device_status(uint16_t index)
1220 {
1221         if (index)
1222                 return -USB_NODEV_ERROR;
1223
1224         InData = ((uint32_t)udc.feature) & 0xff;
1225         __usb_ep_write(CTRL_ENP_IN,
1226                         (uint8_t *)&InData, sizeof(uint16_t),
1227                         usb_status_handler);
1228         return 0;
1229 }
1230
1231 /* Get interface status */
1232 static int usb_send_interface_status(UNUSED_ARG(uint16_t, index))
1233 {
1234         InData = 0;
1235         __usb_ep_write(CTRL_ENP_IN,
1236                         (uint8_t *)&InData, sizeof(uint16_t),
1237                         usb_status_handler);
1238         return 0;
1239 }
1240
1241 /* Get endpoint status */
1242 static int usb_send_ep_status(uint16_t index)
1243 {
1244         if ((index & 0x7F) > 16)
1245                 return -USB_NODEV_ERROR;
1246
1247         InData = 0;
1248         usb_ep_get_stall(usb_ep_logical_to_hw(index), (bool *)&InData);
1249         __usb_ep_write(CTRL_ENP_IN,
1250                         (uint8_t *)&InData, sizeof(uint16_t),
1251                         usb_status_handler);
1252         return 0;
1253 }
1254
1255 /* USB setup packet: GET_STATUS request handler */
1256 static void usb_get_status_handler(void)
1257 {
1258         uint16_t w_value = usb_le16_to_cpu(setup_packet.wValue);
1259         uint16_t w_index = usb_le16_to_cpu(setup_packet.wIndex);
1260         uint16_t w_length = usb_le16_to_cpu(setup_packet.wLength);
1261
1262         /* GET_STATUS sanity checks */
1263         if (udc.state < USB_STATE_ADDRESS)
1264         {
1265                 LOG_WARN("%s: bad GET_STATUS request (State=%02x)\n",
1266                                 __func__, udc.state);
1267                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1268                 return;
1269         }
1270         if (w_length != 2)
1271         {
1272                 LOG_WARN("%s: bad GET_STATUS request (wLength.Word=%02x)\n",
1273                                 __func__, w_length);
1274                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1275                 return;
1276         }
1277         if (!(setup_packet.mRequestType & USB_DIR_IN))
1278         {
1279                 LOG_WARN("%s: bad GET_STATUS request (mRequestType=%02x)\n",
1280                                 __func__, setup_packet.mRequestType);
1281                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1282                 return;
1283         }
1284         if (w_value)
1285         {
1286                 LOG_WARN("%s: bad GET_STATUS request (wValue=%02x)\n",
1287                                 __func__, w_value);
1288                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1289                 return;
1290         }
1291
1292         /* Process GET_STATUS request */
1293         switch (setup_packet.mRequestType & USB_RECIP_MASK)
1294         {
1295         case USB_RECIP_DEVICE:
1296                 if (usb_send_device_status(w_index) < 0)
1297                 {
1298                         LOG_WARN("%s: GET_STATUS: invalid UsbRecipientDevice\n",
1299                                         __func__);
1300                         ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1301                         return;
1302                 }
1303                 LOG_INFO("%s: GET_STATUS: mRequestType=%02x (UsbRecipientDevice)\n",
1304                                 __func__, setup_packet.mRequestType);
1305                 break;
1306         case USB_RECIP_INTERFACE:
1307                 if (usb_send_interface_status(w_index) < 0)
1308                 {
1309                         LOG_WARN("%s: GET_STATUS: invalid UsbRecipientInterface\n",
1310                                         __func__);
1311                         ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1312                         return;
1313                 }
1314                 LOG_INFO("%s: GET_STATUS: mRequestType=%02x (UsbRecipientInterface)\n",
1315                                 __func__, setup_packet.mRequestType);
1316                 break;
1317         case USB_RECIP_ENDPOINT:
1318                 if (usb_send_ep_status(w_index) < 0)
1319                 {
1320                         LOG_WARN("%s: GET_STATUS: invalid UsbRecipientEndpoint\n",
1321                                         __func__);
1322                         ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1323                         return;
1324                 }
1325                 LOG_INFO("%s: GET_STATUS: mRequestType=%02x (UsbRecipientEndpoint)\n",
1326                                 __func__, setup_packet.mRequestType);
1327                 break;
1328         default:
1329                 LOG_WARN("%s: GET_STATUS: invalid UsbRecipientEndpoint\n",
1330                                 __func__);
1331                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1332                 break;
1333         }
1334 }
1335
1336 static int usb_get_device_descriptor(int id)
1337 {
1338         if (id)
1339                 return -USB_NODEV_ERROR;
1340
1341         usb_dev->device->bMaxPacketSize0 = USB_EP0_MAX_SIZE;
1342         __usb_ep_write(CTRL_ENP_IN, (const uint8_t *)usb_dev->device,
1343                         usb_size(usb_dev->device->bLength,
1344                                 usb_le16_to_cpu(setup_packet.wLength)),
1345                         usb_status_handler);
1346         return 0;
1347 }
1348
1349 /*
1350  * TODO: refactor this part to remove this temporary buffer.
1351  *
1352  * It would be better to define all the USB descriptors in the right order and
1353  * send them as a contiguous buffer directly from the flash / rodata memory.
1354  */
1355 #define USB_BUFSIZE (128)
1356 static uint8_t usb_cfg_buffer[USB_BUFSIZE];
1357 STATIC_ASSERT(USB_BUFSIZE < (1 << (sizeof(uint16_t) * 8)));
1358
1359 static int usb_get_configuration_descriptor(int id)
1360 {
1361         const UsbConfigDesc **config =
1362                         (const UsbConfigDesc **)usb_dev->config;
1363         uint8_t *p = usb_cfg_buffer;
1364         int i;
1365
1366         /* TODO: support more than one configuration per device */
1367         if (UNLIKELY(id > 0))
1368                 return -USB_NODEV_ERROR;
1369
1370         for (i = 0; config[i]; i++)
1371         {
1372                 memcpy(p, config[i], config[i]->bLength);
1373                 p += config[i]->bLength;
1374
1375                 if (UNLIKELY((p - usb_cfg_buffer) > USB_BUFSIZE))
1376                 {
1377                         ASSERT(0);
1378                         return -USB_BUF_OVERFLOW;
1379                 }
1380         }
1381         ((UsbConfigDesc *)usb_cfg_buffer)->wTotalLength =
1382                         usb_cpu_to_le16((uint16_t)(p - usb_cfg_buffer));
1383         __usb_ep_write(CTRL_ENP_IN,
1384                         usb_cfg_buffer,
1385                         usb_size(p - usb_cfg_buffer,
1386                                 usb_le16_to_cpu(setup_packet.wLength)),
1387                         usb_status_handler);
1388         return 0;
1389 }
1390
1391 static int usb_get_string_descriptor(unsigned int id)
1392 {
1393         const UsbStringDesc *lang_str;
1394         unsigned int lang_id, str_id;
1395         uint16_t w_index_lo = usb_le16_to_cpu(setup_packet.wIndex) & 0x00ff;
1396         uint16_t w_index_hi = (usb_le16_to_cpu(setup_packet.wIndex) &
1397                                                 0xff00) >> 8;
1398
1399         ASSERT(usb_dev->strings != NULL);
1400         ASSERT(usb_dev->strings[0] != NULL);
1401
1402         lang_str = usb_dev->strings[0];
1403         if (id)
1404         {
1405                 /* Find Language index */
1406                 for (lang_id = 0; ; lang_id++)
1407                 {
1408                         const UsbStringDesc *str =
1409                                                 usb_dev->strings[lang_id];
1410                         if (UNLIKELY(str == NULL))
1411                                 return -USB_NODEV_ERROR;
1412                         if ((str->data[0] == w_index_lo) &&
1413                                         (str->data[1] == w_index_hi))
1414                                 break;
1415                 }
1416                 /* Check buffer overflow to find string index */
1417                 for (str_id = 0; str_id < id; str_id++)
1418                 {
1419                         lang_str = usb_dev->strings[lang_id + 1 + str_id];
1420                         if (lang_str == NULL)
1421                                 return -USB_NODEV_ERROR;
1422                 }
1423         }
1424         __usb_ep_write(CTRL_ENP_IN,
1425                         lang_str,
1426                         usb_size(lang_str->bLength,
1427                                 usb_le16_to_cpu(setup_packet.wLength)),
1428                         usb_status_handler);
1429         return 0;
1430 }
1431
1432 static void usb_get_descriptor(void)
1433 {
1434         uint16_t w_value_lo = usb_le16_to_cpu(setup_packet.wValue) & 0x00ff;
1435         uint16_t w_value_hi = (usb_le16_to_cpu(setup_packet.wValue) & 0xff00) >> 8;
1436
1437         if (udc.state < USB_STATE_DEFAULT)
1438         {
1439                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1440                 return;
1441         }
1442         switch (w_value_hi)
1443         {
1444         case USB_DT_DEVICE:
1445                 LOG_INFO("%s: GET_DEVICE_DESCRIPTOR: id=%d, state=%d\n",
1446                                 __func__,
1447                                 w_value_lo,
1448                                 udc.state);
1449                 if (usb_get_device_descriptor(w_value_lo) < 0)
1450                         ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1451                 break;
1452         case USB_DT_CONFIG:
1453                 LOG_INFO("%s: GET_CONFIG_DESCRIPTOR: id=%d, state=%d\n",
1454                                 __func__, w_value_lo, udc.state);
1455                 if (usb_get_configuration_descriptor(w_value_lo) < 0)
1456                         ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1457                 break;
1458         case USB_DT_STRING:
1459                 LOG_INFO("%s: GET_STRING_DESCRIPTOR: id=%d, state=%d\n",
1460                                 __func__, w_value_lo, udc.state);
1461                 if (usb_get_string_descriptor(w_value_lo) < 0)
1462                         ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1463                 break;
1464         default:
1465                 LOG_WARN("%s: GET_UNKNOWN_DESCRIPTOR: id=%d, state=%d\n",
1466                                 __func__, w_value_lo, udc.state);
1467                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1468                 break;
1469         }
1470 }
1471
1472 /* USB setup packet: class/vendor request handler */
1473 static void usb_event_handler(UsbDevice *dev)
1474 {
1475         /*
1476          * TODO: get the appropriate usb_dev in function of the endpoint
1477          * address.
1478          */
1479         if (dev->event_cb)
1480                 dev->event_cb(&setup_packet);
1481 }
1482
1483 /* USB setup packet: GET_DESCRIPTOR handler */
1484 static void usb_get_descriptor_handler(void)
1485 {
1486         LOG_INFO("%s: GET_DESCRIPTOR: RECIP = %d\n",
1487                         __func__,
1488                         setup_packet.mRequestType & USB_RECIP_MASK);
1489         if ((setup_packet.mRequestType & USB_RECIP_MASK) ==
1490                         USB_RECIP_DEVICE)
1491                 usb_get_descriptor();
1492         /* Getting descriptor for a device is a standard request */
1493         else if ((setup_packet.mRequestType & USB_DIR_MASK) == USB_DIR_IN)
1494                 usb_event_handler(usb_dev);
1495         else
1496                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1497 }
1498
1499 /* USB setup packet: SET_ADDRESS handler */
1500 static void usb_set_address_handler(void)
1501 {
1502         uint16_t w_value = usb_le16_to_cpu(setup_packet.wValue);
1503         uint16_t w_index = usb_le16_to_cpu(setup_packet.wIndex);
1504         uint16_t w_length = usb_le16_to_cpu(setup_packet.wLength);
1505
1506         LOG_INFO("%s: SET_ADDRESS: %d\n",
1507                         __func__, usb_le16_to_cpu(setup_packet.wValue));
1508         if ((udc.state >= USB_STATE_DEFAULT) &&
1509                         ((setup_packet.mRequestType & USB_RECIP_MASK) ==
1510                                         USB_RECIP_DEVICE) &&
1511                         (w_index == 0) && (w_length == 0) && (w_value < 128))
1512                 usb_status_handler(CTRL_ENP_IN);
1513         else
1514                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1515 }
1516
1517 /* USB setup packet: GET_CONFIGURATION handler */
1518 static void usb_get_config_handler(void)
1519 {
1520         uint16_t w_value = usb_le16_to_cpu(setup_packet.wValue);
1521         uint16_t w_index = usb_le16_to_cpu(setup_packet.wIndex);
1522
1523         LOG_INFO("%s: GET_CONFIGURATION\n", __func__);
1524         if ((udc.state >= USB_STATE_ADDRESS) &&
1525                         (w_value == 0) && (w_index == 0) && (w_value == 1))
1526         {
1527                 InData = udc.cfg_id;
1528                 __usb_ep_write(CTRL_ENP_IN, (uint8_t *)&InData, 1, usb_status_handler);
1529         }
1530         else
1531                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1532 }
1533
1534 static const UsbConfigDesc *usb_find_configuration(int num)
1535 {
1536         const UsbConfigDesc *cfg;
1537         int i;
1538
1539         for (i = 0; ; i++)
1540         {
1541                 cfg = (const UsbConfigDesc *)usb_dev->config[i];
1542                 if (cfg == NULL)
1543                         break;
1544                 if (cfg->bDescriptorType != USB_DT_CONFIG)
1545                         continue;
1546                 if (cfg->bConfigurationValue == num)
1547                         return cfg;
1548         }
1549         return NULL;
1550 }
1551
1552 static int usb_set_config_state(uint32_t conf)
1553 {
1554         const UsbConfigDesc *pCnfg;
1555         unsigned int i;
1556
1557         if (conf)
1558         {
1559                 /* Find configuration descriptor */
1560                 pCnfg = usb_find_configuration(conf);
1561                 if (pCnfg == NULL)
1562                         return -USB_NODEV_ERROR;
1563
1564                 /* Reset current configuration */
1565                 usb_set_device_state(USB_STATE_ADDRESS);
1566                 usb_dev->configured = false;
1567                 udc.cfg = pCnfg;
1568
1569                 /* Set Interface and Alternative Setting */
1570                 udc.cfg_id = conf;
1571                 /* Set self-powered state */
1572                 if (pCnfg->bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1573                         udc.feature |= STM32_UDC_FEATURE_SELFPOWERED;
1574
1575                 /* Configure all existing interfaces to alternative setting 0 */
1576                 ASSERT(pCnfg->bNumInterfaces <= USB_MAX_INTERFACE);
1577                 udc.interfaces = pCnfg->bNumInterfaces;
1578                 for (i = 0; i < udc.interfaces; i++)
1579                         udc.alt[i] = 0;
1580                 usb_set_device_state(USB_STATE_CONFIGURED);
1581                 usb_dev->configured = true;
1582                 LOG_INFO("%s: device configured\n", __func__);
1583         }
1584         else
1585         {
1586                 usb_dev->configured = false;
1587                 usb_set_device_state(USB_STATE_ADDRESS);
1588         }
1589         return 0;
1590 }
1591
1592 /* USB setup packet: SET_CONFIGURATION handler */
1593 static void usb_set_config_handler(void)
1594 {
1595         uint16_t w_value = usb_le16_to_cpu(setup_packet.wValue);
1596         uint16_t w_index = usb_le16_to_cpu(setup_packet.wIndex);
1597         uint16_t w_length = usb_le16_to_cpu(setup_packet.wLength);
1598
1599         LOG_INFO("%s: SET_CONFIGURATION: %d\n",
1600                         __func__, w_value);
1601         if ((udc.state >= USB_STATE_ADDRESS) &&
1602                         (w_index == 0) && (w_length == 0) &&
1603                         (usb_set_config_state(w_value & 0xff) == 0))
1604                 usb_status_handler(CTRL_ENP_OUT);
1605         else
1606                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1607 }
1608
1609 /* USB setup packet: standard request handler */
1610 static void usb_standard_request_handler(void)
1611 {
1612         switch (setup_packet.bRequest)
1613         {
1614         case USB_REQ_GET_STATUS:
1615                 usb_get_status_handler();
1616                 break;
1617         case USB_REQ_CLEAR_FEATURE:
1618                 LOG_INFO("%s: bRequest=%d (CLEAR_FEATURE)\n",
1619                                 __func__, setup_packet.bRequest);
1620                 break;
1621         case USB_REQ_SET_FEATURE:
1622                 LOG_INFO("%s: bRequest=%d (SET_FEATURE)\n",
1623                                 __func__, setup_packet.bRequest);
1624                 break;
1625         case USB_REQ_SET_ADDRESS:
1626                 usb_set_address_handler();
1627                 break;
1628         case USB_REQ_GET_DESCRIPTOR:
1629                 usb_get_descriptor_handler();
1630                 break;
1631         case USB_REQ_SET_DESCRIPTOR:
1632                 LOG_INFO("%s: bRequest=%d (SET_DESCRIPTOR)\n",
1633                                 __func__, setup_packet.bRequest);
1634                 break;
1635         case USB_REQ_GET_CONFIGURATION:
1636                 usb_get_config_handler();
1637                 break;
1638         case USB_REQ_SET_CONFIGURATION:
1639                 usb_set_config_handler();
1640                 break;
1641         case USB_REQ_GET_INTERFACE:
1642                 LOG_INFO("%s: bRequest=%d (GET_INTERFACE)\n",
1643                                 __func__, setup_packet.bRequest);
1644                 break;
1645         case USB_REQ_SET_INTERFACE:
1646                 LOG_INFO("%s: bRequest=%d (SET_INTERFACE)\n",
1647                                 __func__, setup_packet.bRequest);
1648                 break;
1649         case USB_REQ_SYNCH_FRAME:
1650                 LOG_INFO("%s: bRequest=%d (SYNCH_FRAME)\n",
1651                                 __func__, setup_packet.bRequest);
1652                 break;
1653         default:
1654                 LOG_WARN("%s: bRequest=%d (Unknown)\n",
1655                                 __func__, setup_packet.bRequest);
1656                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1657                 break;
1658         }
1659 }
1660
1661 /* USB setup packet handler */
1662 static void usb_setup_handler(void)
1663 {
1664         switch (setup_packet.mRequestType & USB_TYPE_MASK)
1665         {
1666         /* Standard */
1667         case USB_TYPE_STANDARD:
1668                 LOG_INFO("%s: bmRequestType=%02x (Standard)\n",
1669                                 __func__, setup_packet.mRequestType);
1670                 usb_standard_request_handler();
1671                 break;
1672         /* Class */
1673         case USB_TYPE_CLASS:
1674                 LOG_INFO("%s: bmRequestType=%02x (Class)\n",
1675                                 __func__, setup_packet.mRequestType);
1676                 usb_event_handler(usb_dev);
1677                 break;
1678         /* Vendor */
1679         case USB_TYPE_VENDOR:
1680                 LOG_INFO("%s: bmRequestType=%02x (Vendor)\n",
1681                                 __func__, setup_packet.mRequestType);
1682                 usb_event_handler(usb_dev);
1683                 break;
1684         case USB_TYPE_RESERVED:
1685                 LOG_INFO("%s: bmRequestType=%02x (Reserved)\n",
1686                                 __func__, setup_packet.mRequestType);
1687                 break;
1688         /* Other */
1689         default:
1690                 LOG_WARN("%s: bmRequestType=%02x (Unknown)\n",
1691                                 __func__, setup_packet.mRequestType);
1692                 ep_cnfg[CTRL_ENP_OUT].status = STALLED;
1693                 break;
1694         }
1695 }
1696
1697 /* USB: low-level hardware initialization */
1698 static void usb_hw_reset(void)
1699 {
1700         unsigned int i;
1701         int ret;
1702
1703         /* Initialize endpoint descriptors */
1704         for (i = 0; i < countof(ep_cnfg); i++)
1705                 ep_cnfg[i].hw = NULL;
1706
1707         /* Initialize USB memory */
1708         for (i = 0; i < countof(memory_buffer); i++)
1709                 memory_buffer[i].Size = 0;
1710         usb->BTABLE = USB_BDT_OFFSET;
1711         mem_use = NULL;
1712
1713         /* Endpoint initialization */
1714         ret = usb_ep_configure(&USB_CtrlEpDescr0, true);
1715         if (UNLIKELY(ret < 0))
1716         {
1717                 LOG_WARN("%s: out of memory, cannot initialize EP0\n",
1718                                 __func__);
1719                 return;
1720         }
1721         ret = usb_ep_configure(&USB_CtrlEpDescr1, true);
1722         if (UNLIKELY(ret < 0))
1723         {
1724                 LOG_WARN("%s: out of memory, cannot initialize EP1\n",
1725                                 __func__);
1726                 return;
1727         }
1728
1729         /* Set default address */
1730         usb_set_address(0);
1731
1732         /* Enable all the device interrupts */
1733         usb->CNTR = bmCTRM | bmRESETM | bmSOFM | bmERRM | bmPMAOVRM |
1734                         bmSUSPM | bmWKUPM;
1735 }
1736
1737 /* Handle a correct transfer under ISR */
1738 static void usb_isr_correct_transfer(stm32_usb_irq_status_t interrupt)
1739 {
1740         int EP;
1741         reg32_t *pReg = (reg32_t *)&usb->EP0R;
1742
1743         /* Find corresponding EP */
1744         pReg += interrupt.EP_ID;
1745         EP = (int)(((*pReg & 0x0f) << 1) + (interrupt.DIR ? 0 : 1));
1746         ep_cnfg[EP].avail_data = 1;
1747
1748         ASSERT(ep_cnfg[EP].hw);
1749         /* IN EP */
1750         if (EP & 0x01)
1751                 ep_ctrl_clr_ctr_tx(ep_cnfg[EP].hw);
1752         else
1753                 ep_ctrl_clr_ctr_rx(ep_cnfg[EP].hw);
1754         if (EP == CTRL_ENP_OUT)
1755         {
1756                 /* Determinate type of packet (only for control EP) */
1757                 bool SetupPacket = ep_ctrl_get_setup(ep_cnfg[CTRL_ENP_OUT].hw);
1758
1759                 if (SetupPacket)
1760                 {
1761                         ep_cnfg[CTRL_ENP_IN].avail_data = 1;
1762                         /* init IO to receive Setup packet */
1763                         __usb_ep_write(CTRL_ENP_IN, NULL, -1, NULL);
1764                         __usb_ep_read(CTRL_ENP_OUT, &setup_packet,
1765                                         sizeof(setup_packet), NULL);
1766
1767                         /* reset EP IO ctrl */
1768                         if (setup_packet.mRequestType & USB_DIR_IN)
1769                                 usb_status_handler(CTRL_ENP_OUT);
1770                         usb_setup_handler();
1771                         if (ep_cnfg[CTRL_ENP_OUT].status == STALLED)
1772                                 usb_ep_set_stall_ctrl();
1773                 }
1774                 else
1775                 {
1776                         if (ep_cnfg[CTRL_ENP_OUT].complete &&
1777                                         setup_packet.mRequestType & USB_DIR_IN)
1778                                 ep_cnfg[CTRL_ENP_OUT].complete(CTRL_ENP_OUT);
1779                         else
1780                                 __usb_ep_io(EP);
1781                 }
1782         }
1783         else if (EP == CTRL_ENP_IN)
1784         {
1785                 if (ep_cnfg[CTRL_ENP_IN].complete &&
1786                                 !(setup_packet.mRequestType & USB_DIR_IN))
1787                         ep_cnfg[CTRL_ENP_IN].complete(CTRL_ENP_IN);
1788                 else
1789                         __usb_ep_io(EP);
1790
1791         }
1792         else
1793                 __usb_ep_io(EP);
1794 }
1795
1796 /* USB: interrupt service routine */
1797 static void usb_isr(void)
1798 {
1799         stm32_usb_irq_status_t interrupt;
1800
1801         /* Get masked interrupt flags */
1802         interrupt.status = usb->ISTR;
1803         interrupt.status &= usb->CNTR | 0x1f;
1804
1805         if (interrupt.PMAOVR)
1806         {
1807                 LOG_WARN("%s: DMA overrun / underrun\n", __func__);
1808                 usb->ISTR = ~bmPMAOVRM;
1809         }
1810         if (interrupt.ERR)
1811         {
1812                 LOG_WARN("%s: engine error\n", __func__);
1813                 usb->ISTR = ~bmERRM;
1814         }
1815         if (interrupt.RESET)
1816         {
1817                 LOG_INFO("%s: device reset\n", __func__);
1818                 usb->ISTR = ~bmRESETM;
1819                 usb_hw_reset();
1820                 usb_set_device_state(USB_STATE_DEFAULT);
1821         }
1822         if (interrupt.SOF)
1823         {
1824 #if 0
1825                 /*
1826                  * XXX: disable logging of frame interrupts (too much noise!)
1827                  */
1828                 uint16_t frame_nr = usb->FNR & 0x0fff;
1829                 LOG_INFO("%s: frame %#x\n", __func__, frame_nr);
1830 #endif
1831                 usb->ISTR = ~bmSOFM;
1832         }
1833         if (interrupt.WKUP)
1834         {
1835                 LOG_INFO("%s: wake-up\n", __func__);
1836                 usb->ISTR = ~(bmSUSPM | bmWKUPM);
1837                 usb_resume();
1838         }
1839         if (interrupt.SUSP)
1840         {
1841                 LOG_INFO("%s: suspend\n", __func__);
1842                 usb_suspend();
1843                 usb->ISTR = ~(bmSUSPM | bmWKUPM);
1844         }
1845         if (interrupt.ESOF)
1846         {
1847                 LOG_INFO("%s: expected frame\n", __func__);
1848                 usb->ISTR = ~bmESOFM;
1849         }
1850         if (interrupt.CTR)
1851         {
1852                 usb_isr_correct_transfer(interrupt);
1853         }
1854 }
1855
1856 /* USB: hardware initialization */
1857 static void usb_hw_init(void)
1858 {
1859         /* Enable clocking on the required GPIO pins */
1860         RCC->APB2ENR |= RCC_APB2_GPIOA | RCC_APB2_GPIOC;
1861
1862         /* Make sure that the CAN controller is disabled and held in reset */
1863         RCC->APB1ENR &= ~RCC_APB1_CAN;
1864
1865         /* Configure USB_DM and USB_DP to work as USB lines */
1866         stm32_gpioPinConfig((struct stm32_gpio *)GPIOA_BASE,
1867                         USB_DM_PIN | USB_DP_PIN,
1868                         GPIO_MODE_AF_PP, GPIO_SPEED_50MHZ);
1869         /* Configure USB_DISC to work as USB disconnect */
1870         stm32_gpioPinConfig((struct stm32_gpio *)GPIOC_BASE,
1871                         USB_DISC_PIN,
1872                         GPIO_MODE_OUT_PP, GPIO_SPEED_50MHZ);
1873         stm32_gpioPinWrite((struct stm32_gpio *)GPIOC_BASE,
1874                                 USB_DISC_PIN, 1);
1875
1876         /* Ensure the USB clock is disabled before setting the prescaler */
1877         RCC->APB1ENR &= ~RCC_APB1_USB;
1878
1879         /* Configure USB clock (48MHz) */
1880         *CFGR_USBPRE_BB &= ~RCC_USBCLK_PLLCLK_1DIV5;
1881
1882         /* Activate USB clock */
1883         RCC->APB1ENR |= RCC_APB1_USB;
1884
1885         /* Force USB reset and disable USB interrupts */
1886         usb->CNTR = bmFRES;
1887         timer_delayHp(1);
1888
1889         /* Issue a USB reset */
1890         usb_hw_reset();
1891
1892         /* Clear spurious pending interrupt */
1893         usb->ISTR = 0;
1894
1895         /* Register interrupt handler */
1896         sysirq_setHandler(USB_LP_CAN_RX0_IRQHANDLER, usb_isr);
1897
1898         /* Software connection enable */
1899         usb_connect();
1900 }
1901
1902 /* Initialize the USB controller */
1903 static void usb_init(void)
1904 {
1905         udc.state = USB_STATE_NOTATTACHED;
1906         udc.feature = 0;
1907
1908         usb_hw_init();
1909 }
1910
1911 /* Register an upper layer USB device into the driver */
1912 int usb_deviceRegister(UsbDevice *dev)
1913 {
1914 #if CONFIG_KERN
1915         MOD_CHECK(proc);
1916 #endif
1917         usb_dev = dev;
1918         usb_init();
1919         while (!usb_dev->configured)
1920                 cpu_relax();
1921         return 0;
1922 }