1 /* 2 * MUSB OTG peripheral driver ep0 handling 3 * 4 * Copyright 2005 Mentor Graphics Corporation 5 * Copyright (C) 2005-2006 by Texas Instruments 6 * Copyright (C) 2006-2007 Nokia Corporation 7 * Copyright (C) 2008-2009 MontaVista Software, Inc. <source@mvista.com> 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License 11 * version 2 as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 21 * 02110-1301 USA 22 * 23 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED 24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN 26 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 29 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 30 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 * 34 */ 35 36 #include <linux/kernel.h> 37 #include <linux/list.h> 38 #include <linux/timer.h> 39 #include <linux/spinlock.h> 40 #include <linux/init.h> 41 #include <linux/device.h> 42 #include <linux/interrupt.h> 43 44 #include "musb_core.h" 45 46 /* ep0 is always musb->endpoints[0].ep_in */ 47 #define next_ep0_request(musb) next_in_request(&(musb)->endpoints[0]) 48 49 /* 50 * locking note: we use only the controller lock, for simpler correctness. 51 * It's always held with IRQs blocked. 52 * 53 * It protects the ep0 request queue as well as ep0_state, not just the 54 * controller and indexed registers. And that lock stays held unless it 55 * needs to be dropped to allow reentering this driver ... like upcalls to 56 * the gadget driver, or adjusting endpoint halt status. 57 */ 58 59 static char *decode_ep0stage(u8 stage) 60 { 61 switch (stage) { 62 case MUSB_EP0_STAGE_IDLE: return "idle"; 63 case MUSB_EP0_STAGE_SETUP: return "setup"; 64 case MUSB_EP0_STAGE_TX: return "in"; 65 case MUSB_EP0_STAGE_RX: return "out"; 66 case MUSB_EP0_STAGE_ACKWAIT: return "wait"; 67 case MUSB_EP0_STAGE_STATUSIN: return "in/status"; 68 case MUSB_EP0_STAGE_STATUSOUT: return "out/status"; 69 default: return "?"; 70 } 71 } 72 73 /* handle a standard GET_STATUS request 74 * Context: caller holds controller lock 75 */ 76 static int service_tx_status_request( 77 struct musb *musb, 78 const struct usb_ctrlrequest *ctrlrequest) 79 { 80 void __iomem *mbase = musb->mregs; 81 int handled = 1; 82 u8 result[2], epnum = 0; 83 const u8 recip = ctrlrequest->bRequestType & USB_RECIP_MASK; 84 85 result[1] = 0; 86 87 switch (recip) { 88 case USB_RECIP_DEVICE: 89 result[0] = musb->is_self_powered << USB_DEVICE_SELF_POWERED; 90 result[0] |= musb->may_wakeup << USB_DEVICE_REMOTE_WAKEUP; 91 #ifdef CONFIG_USB_MUSB_OTG 92 if (musb->g.is_otg) { 93 result[0] |= musb->g.b_hnp_enable 94 << USB_DEVICE_B_HNP_ENABLE; 95 result[0] |= musb->g.a_alt_hnp_support 96 << USB_DEVICE_A_ALT_HNP_SUPPORT; 97 result[0] |= musb->g.a_hnp_support 98 << USB_DEVICE_A_HNP_SUPPORT; 99 } 100 #endif 101 break; 102 103 case USB_RECIP_INTERFACE: 104 result[0] = 0; 105 break; 106 107 case USB_RECIP_ENDPOINT: { 108 int is_in; 109 struct musb_ep *ep; 110 u16 tmp; 111 void __iomem *regs; 112 113 epnum = (u8) ctrlrequest->wIndex; 114 if (!epnum) { 115 result[0] = 0; 116 break; 117 } 118 119 is_in = epnum & USB_DIR_IN; 120 if (is_in) { 121 epnum &= 0x0f; 122 ep = &musb->endpoints[epnum].ep_in; 123 } else { 124 ep = &musb->endpoints[epnum].ep_out; 125 } 126 regs = musb->endpoints[epnum].regs; 127 128 if (epnum >= MUSB_C_NUM_EPS || !ep->desc) { 129 handled = -EINVAL; 130 break; 131 } 132 133 musb_ep_select(mbase, epnum); 134 if (is_in) 135 tmp = musb_readw(regs, MUSB_TXCSR) 136 & MUSB_TXCSR_P_SENDSTALL; 137 else 138 tmp = musb_readw(regs, MUSB_RXCSR) 139 & MUSB_RXCSR_P_SENDSTALL; 140 musb_ep_select(mbase, 0); 141 142 result[0] = tmp ? 1 : 0; 143 } break; 144 145 default: 146 /* class, vendor, etc ... delegate */ 147 handled = 0; 148 break; 149 } 150 151 /* fill up the fifo; caller updates csr0 */ 152 if (handled > 0) { 153 u16 len = le16_to_cpu(ctrlrequest->wLength); 154 155 if (len > 2) 156 len = 2; 157 musb_write_fifo(&musb->endpoints[0], len, result); 158 } 159 160 return handled; 161 } 162 163 /* 164 * handle a control-IN request, the end0 buffer contains the current request 165 * that is supposed to be a standard control request. Assumes the fifo to 166 * be at least 2 bytes long. 167 * 168 * @return 0 if the request was NOT HANDLED, 169 * < 0 when error 170 * > 0 when the request is processed 171 * 172 * Context: caller holds controller lock 173 */ 174 static int 175 service_in_request(struct musb *musb, const struct usb_ctrlrequest *ctrlrequest) 176 { 177 int handled = 0; /* not handled */ 178 179 if ((ctrlrequest->bRequestType & USB_TYPE_MASK) 180 == USB_TYPE_STANDARD) { 181 switch (ctrlrequest->bRequest) { 182 case USB_REQ_GET_STATUS: 183 handled = service_tx_status_request(musb, 184 ctrlrequest); 185 break; 186 187 /* case USB_REQ_SYNC_FRAME: */ 188 189 default: 190 break; 191 } 192 } 193 return handled; 194 } 195 196 /* 197 * Context: caller holds controller lock 198 */ 199 static void musb_g_ep0_giveback(struct musb *musb, struct usb_request *req) 200 { 201 musb_g_giveback(&musb->endpoints[0].ep_in, req, 0); 202 } 203 204 /* 205 * Tries to start B-device HNP negotiation if enabled via sysfs 206 */ 207 static inline void musb_try_b_hnp_enable(struct musb *musb) 208 { 209 void __iomem *mbase = musb->mregs; 210 u8 devctl; 211 212 dev_dbg(musb->controller, "HNP: Setting HR\n"); 213 devctl = musb_readb(mbase, MUSB_DEVCTL); 214 musb_writeb(mbase, MUSB_DEVCTL, devctl | MUSB_DEVCTL_HR); 215 } 216 217 /* 218 * Handle all control requests with no DATA stage, including standard 219 * requests such as: 220 * USB_REQ_SET_CONFIGURATION, USB_REQ_SET_INTERFACE, unrecognized 221 * always delegated to the gadget driver 222 * USB_REQ_SET_ADDRESS, USB_REQ_CLEAR_FEATURE, USB_REQ_SET_FEATURE 223 * always handled here, except for class/vendor/... features 224 * 225 * Context: caller holds controller lock 226 */ 227 static int 228 service_zero_data_request(struct musb *musb, 229 struct usb_ctrlrequest *ctrlrequest) 230 __releases(musb->lock) 231 __acquires(musb->lock) 232 { 233 int handled = -EINVAL; 234 void __iomem *mbase = musb->mregs; 235 const u8 recip = ctrlrequest->bRequestType & USB_RECIP_MASK; 236 237 /* the gadget driver handles everything except what we MUST handle */ 238 if ((ctrlrequest->bRequestType & USB_TYPE_MASK) 239 == USB_TYPE_STANDARD) { 240 switch (ctrlrequest->bRequest) { 241 case USB_REQ_SET_ADDRESS: 242 /* change it after the status stage */ 243 musb->set_address = true; 244 musb->address = (u8) (ctrlrequest->wValue & 0x7f); 245 handled = 1; 246 break; 247 248 case USB_REQ_CLEAR_FEATURE: 249 switch (recip) { 250 case USB_RECIP_DEVICE: 251 if (ctrlrequest->wValue 252 != USB_DEVICE_REMOTE_WAKEUP) 253 break; 254 musb->may_wakeup = 0; 255 handled = 1; 256 break; 257 case USB_RECIP_INTERFACE: 258 break; 259 case USB_RECIP_ENDPOINT:{ 260 const u8 epnum = 261 ctrlrequest->wIndex & 0x0f; 262 struct musb_ep *musb_ep; 263 struct musb_hw_ep *ep; 264 struct musb_request *request; 265 void __iomem *regs; 266 int is_in; 267 u16 csr; 268 269 if (epnum == 0 || epnum >= MUSB_C_NUM_EPS || 270 ctrlrequest->wValue != USB_ENDPOINT_HALT) 271 break; 272 273 ep = musb->endpoints + epnum; 274 regs = ep->regs; 275 is_in = ctrlrequest->wIndex & USB_DIR_IN; 276 if (is_in) 277 musb_ep = &ep->ep_in; 278 else 279 musb_ep = &ep->ep_out; 280 if (!musb_ep->desc) 281 break; 282 283 handled = 1; 284 /* Ignore request if endpoint is wedged */ 285 if (musb_ep->wedged) 286 break; 287 288 musb_ep_select(mbase, epnum); 289 if (is_in) { 290 csr = musb_readw(regs, MUSB_TXCSR); 291 csr |= MUSB_TXCSR_CLRDATATOG | 292 MUSB_TXCSR_P_WZC_BITS; 293 csr &= ~(MUSB_TXCSR_P_SENDSTALL | 294 MUSB_TXCSR_P_SENTSTALL | 295 MUSB_TXCSR_TXPKTRDY); 296 musb_writew(regs, MUSB_TXCSR, csr); 297 } else { 298 csr = musb_readw(regs, MUSB_RXCSR); 299 csr |= MUSB_RXCSR_CLRDATATOG | 300 MUSB_RXCSR_P_WZC_BITS; 301 csr &= ~(MUSB_RXCSR_P_SENDSTALL | 302 MUSB_RXCSR_P_SENTSTALL); 303 musb_writew(regs, MUSB_RXCSR, csr); 304 } 305 306 /* Maybe start the first request in the queue */ 307 request = next_request(musb_ep); 308 if (!musb_ep->busy && request) { 309 dev_dbg(musb->controller, "restarting the request\n"); 310 musb_ep_restart(musb, request); 311 } 312 313 /* select ep0 again */ 314 musb_ep_select(mbase, 0); 315 } break; 316 default: 317 /* class, vendor, etc ... delegate */ 318 handled = 0; 319 break; 320 } 321 break; 322 323 case USB_REQ_SET_FEATURE: 324 switch (recip) { 325 case USB_RECIP_DEVICE: 326 handled = 1; 327 switch (ctrlrequest->wValue) { 328 case USB_DEVICE_REMOTE_WAKEUP: 329 musb->may_wakeup = 1; 330 break; 331 case USB_DEVICE_TEST_MODE: 332 if (musb->g.speed != USB_SPEED_HIGH) 333 goto stall; 334 if (ctrlrequest->wIndex & 0xff) 335 goto stall; 336 337 switch (ctrlrequest->wIndex >> 8) { 338 case 1: 339 pr_debug("TEST_J\n"); 340 /* TEST_J */ 341 musb->test_mode_nr = 342 MUSB_TEST_J; 343 break; 344 case 2: 345 /* TEST_K */ 346 pr_debug("TEST_K\n"); 347 musb->test_mode_nr = 348 MUSB_TEST_K; 349 break; 350 case 3: 351 /* TEST_SE0_NAK */ 352 pr_debug("TEST_SE0_NAK\n"); 353 musb->test_mode_nr = 354 MUSB_TEST_SE0_NAK; 355 break; 356 case 4: 357 /* TEST_PACKET */ 358 pr_debug("TEST_PACKET\n"); 359 musb->test_mode_nr = 360 MUSB_TEST_PACKET; 361 break; 362 363 case 0xc0: 364 /* TEST_FORCE_HS */ 365 pr_debug("TEST_FORCE_HS\n"); 366 musb->test_mode_nr = 367 MUSB_TEST_FORCE_HS; 368 break; 369 case 0xc1: 370 /* TEST_FORCE_FS */ 371 pr_debug("TEST_FORCE_FS\n"); 372 musb->test_mode_nr = 373 MUSB_TEST_FORCE_FS; 374 break; 375 case 0xc2: 376 /* TEST_FIFO_ACCESS */ 377 pr_debug("TEST_FIFO_ACCESS\n"); 378 musb->test_mode_nr = 379 MUSB_TEST_FIFO_ACCESS; 380 break; 381 case 0xc3: 382 /* TEST_FORCE_HOST */ 383 pr_debug("TEST_FORCE_HOST\n"); 384 musb->test_mode_nr = 385 MUSB_TEST_FORCE_HOST; 386 break; 387 default: 388 goto stall; 389 } 390 391 /* enter test mode after irq */ 392 if (handled > 0) 393 musb->test_mode = true; 394 break; 395 #ifdef CONFIG_USB_MUSB_OTG 396 case USB_DEVICE_B_HNP_ENABLE: 397 if (!musb->g.is_otg) 398 goto stall; 399 musb->g.b_hnp_enable = 1; 400 musb_try_b_hnp_enable(musb); 401 break; 402 case USB_DEVICE_A_HNP_SUPPORT: 403 if (!musb->g.is_otg) 404 goto stall; 405 musb->g.a_hnp_support = 1; 406 break; 407 case USB_DEVICE_A_ALT_HNP_SUPPORT: 408 if (!musb->g.is_otg) 409 goto stall; 410 musb->g.a_alt_hnp_support = 1; 411 break; 412 #endif 413 case USB_DEVICE_DEBUG_MODE: 414 handled = 0; 415 break; 416 stall: 417 default: 418 handled = -EINVAL; 419 break; 420 } 421 break; 422 423 case USB_RECIP_INTERFACE: 424 break; 425 426 case USB_RECIP_ENDPOINT:{ 427 const u8 epnum = 428 ctrlrequest->wIndex & 0x0f; 429 struct musb_ep *musb_ep; 430 struct musb_hw_ep *ep; 431 void __iomem *regs; 432 int is_in; 433 u16 csr; 434 435 if (epnum == 0 || epnum >= MUSB_C_NUM_EPS || 436 ctrlrequest->wValue != USB_ENDPOINT_HALT) 437 break; 438 439 ep = musb->endpoints + epnum; 440 regs = ep->regs; 441 is_in = ctrlrequest->wIndex & USB_DIR_IN; 442 if (is_in) 443 musb_ep = &ep->ep_in; 444 else 445 musb_ep = &ep->ep_out; 446 if (!musb_ep->desc) 447 break; 448 449 musb_ep_select(mbase, epnum); 450 if (is_in) { 451 csr = musb_readw(regs, MUSB_TXCSR); 452 if (csr & MUSB_TXCSR_FIFONOTEMPTY) 453 csr |= MUSB_TXCSR_FLUSHFIFO; 454 csr |= MUSB_TXCSR_P_SENDSTALL 455 | MUSB_TXCSR_CLRDATATOG 456 | MUSB_TXCSR_P_WZC_BITS; 457 musb_writew(regs, MUSB_TXCSR, csr); 458 } else { 459 csr = musb_readw(regs, MUSB_RXCSR); 460 csr |= MUSB_RXCSR_P_SENDSTALL 461 | MUSB_RXCSR_FLUSHFIFO 462 | MUSB_RXCSR_CLRDATATOG 463 | MUSB_RXCSR_P_WZC_BITS; 464 musb_writew(regs, MUSB_RXCSR, csr); 465 } 466 467 /* select ep0 again */ 468 musb_ep_select(mbase, 0); 469 handled = 1; 470 } break; 471 472 default: 473 /* class, vendor, etc ... delegate */ 474 handled = 0; 475 break; 476 } 477 break; 478 default: 479 /* delegate SET_CONFIGURATION, etc */ 480 handled = 0; 481 } 482 } else 483 handled = 0; 484 return handled; 485 } 486 487 /* we have an ep0out data packet 488 * Context: caller holds controller lock 489 */ 490 static void ep0_rxstate(struct musb *musb) 491 { 492 void __iomem *regs = musb->control_ep->regs; 493 struct musb_request *request; 494 struct usb_request *req; 495 u16 count, csr; 496 497 request = next_ep0_request(musb); 498 req = &request->request; 499 500 /* read packet and ack; or stall because of gadget driver bug: 501 * should have provided the rx buffer before setup() returned. 502 */ 503 if (req) { 504 void *buf = req->buf + req->actual; 505 unsigned len = req->length - req->actual; 506 507 /* read the buffer */ 508 count = musb_readb(regs, MUSB_COUNT0); 509 if (count > len) { 510 req->status = -EOVERFLOW; 511 count = len; 512 } 513 musb_read_fifo(&musb->endpoints[0], count, buf); 514 req->actual += count; 515 csr = MUSB_CSR0_P_SVDRXPKTRDY; 516 if (count < 64 || req->actual == req->length) { 517 musb->ep0_state = MUSB_EP0_STAGE_STATUSIN; 518 csr |= MUSB_CSR0_P_DATAEND; 519 } else 520 req = NULL; 521 } else 522 csr = MUSB_CSR0_P_SVDRXPKTRDY | MUSB_CSR0_P_SENDSTALL; 523 524 525 /* Completion handler may choose to stall, e.g. because the 526 * message just received holds invalid data. 527 */ 528 if (req) { 529 musb->ackpend = csr; 530 musb_g_ep0_giveback(musb, req); 531 if (!musb->ackpend) 532 return; 533 musb->ackpend = 0; 534 } 535 musb_ep_select(musb->mregs, 0); 536 musb_writew(regs, MUSB_CSR0, csr); 537 } 538 539 /* 540 * transmitting to the host (IN), this code might be called from IRQ 541 * and from kernel thread. 542 * 543 * Context: caller holds controller lock 544 */ 545 static void ep0_txstate(struct musb *musb) 546 { 547 void __iomem *regs = musb->control_ep->regs; 548 struct musb_request *req = next_ep0_request(musb); 549 struct usb_request *request; 550 u16 csr = MUSB_CSR0_TXPKTRDY; 551 u8 *fifo_src; 552 u8 fifo_count; 553 554 if (!req) { 555 /* WARN_ON(1); */ 556 dev_dbg(musb->controller, "odd; csr0 %04x\n", musb_readw(regs, MUSB_CSR0)); 557 return; 558 } 559 560 request = &req->request; 561 562 /* load the data */ 563 fifo_src = (u8 *) request->buf + request->actual; 564 fifo_count = min((unsigned) MUSB_EP0_FIFOSIZE, 565 request->length - request->actual); 566 musb_write_fifo(&musb->endpoints[0], fifo_count, fifo_src); 567 request->actual += fifo_count; 568 569 /* update the flags */ 570 if (fifo_count < MUSB_MAX_END0_PACKET 571 || (request->actual == request->length 572 && !request->zero)) { 573 musb->ep0_state = MUSB_EP0_STAGE_STATUSOUT; 574 csr |= MUSB_CSR0_P_DATAEND; 575 } else 576 request = NULL; 577 578 /* report completions as soon as the fifo's loaded; there's no 579 * win in waiting till this last packet gets acked. (other than 580 * very precise fault reporting, needed by USB TMC; possible with 581 * this hardware, but not usable from portable gadget drivers.) 582 */ 583 if (request) { 584 musb->ackpend = csr; 585 musb_g_ep0_giveback(musb, request); 586 if (!musb->ackpend) 587 return; 588 musb->ackpend = 0; 589 } 590 591 /* send it out, triggering a "txpktrdy cleared" irq */ 592 musb_ep_select(musb->mregs, 0); 593 musb_writew(regs, MUSB_CSR0, csr); 594 } 595 596 /* 597 * Read a SETUP packet (struct usb_ctrlrequest) from the hardware. 598 * Fields are left in USB byte-order. 599 * 600 * Context: caller holds controller lock. 601 */ 602 static void 603 musb_read_setup(struct musb *musb, struct usb_ctrlrequest *req) 604 { 605 struct musb_request *r; 606 void __iomem *regs = musb->control_ep->regs; 607 608 musb_read_fifo(&musb->endpoints[0], sizeof *req, (u8 *)req); 609 610 /* NOTE: earlier 2.6 versions changed setup packets to host 611 * order, but now USB packets always stay in USB byte order. 612 */ 613 dev_dbg(musb->controller, "SETUP req%02x.%02x v%04x i%04x l%d\n", 614 req->bRequestType, 615 req->bRequest, 616 le16_to_cpu(req->wValue), 617 le16_to_cpu(req->wIndex), 618 le16_to_cpu(req->wLength)); 619 620 /* clean up any leftover transfers */ 621 r = next_ep0_request(musb); 622 if (r) 623 musb_g_ep0_giveback(musb, &r->request); 624 625 /* For zero-data requests we want to delay the STATUS stage to 626 * avoid SETUPEND errors. If we read data (OUT), delay accepting 627 * packets until there's a buffer to store them in. 628 * 629 * If we write data, the controller acts happier if we enable 630 * the TX FIFO right away, and give the controller a moment 631 * to switch modes... 632 */ 633 musb->set_address = false; 634 musb->ackpend = MUSB_CSR0_P_SVDRXPKTRDY; 635 if (req->wLength == 0) { 636 if (req->bRequestType & USB_DIR_IN) 637 musb->ackpend |= MUSB_CSR0_TXPKTRDY; 638 musb->ep0_state = MUSB_EP0_STAGE_ACKWAIT; 639 } else if (req->bRequestType & USB_DIR_IN) { 640 musb->ep0_state = MUSB_EP0_STAGE_TX; 641 musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SVDRXPKTRDY); 642 while ((musb_readw(regs, MUSB_CSR0) 643 & MUSB_CSR0_RXPKTRDY) != 0) 644 cpu_relax(); 645 musb->ackpend = 0; 646 } else 647 musb->ep0_state = MUSB_EP0_STAGE_RX; 648 } 649 650 static int 651 forward_to_driver(struct musb *musb, const struct usb_ctrlrequest *ctrlrequest) 652 __releases(musb->lock) 653 __acquires(musb->lock) 654 { 655 int retval; 656 if (!musb->gadget_driver) 657 return -EOPNOTSUPP; 658 spin_unlock(&musb->lock); 659 retval = musb->gadget_driver->setup(&musb->g, ctrlrequest); 660 spin_lock(&musb->lock); 661 return retval; 662 } 663 664 /* 665 * Handle peripheral ep0 interrupt 666 * 667 * Context: irq handler; we won't re-enter the driver that way. 668 */ 669 irqreturn_t musb_g_ep0_irq(struct musb *musb) 670 { 671 u16 csr; 672 u16 len; 673 void __iomem *mbase = musb->mregs; 674 void __iomem *regs = musb->endpoints[0].regs; 675 irqreturn_t retval = IRQ_NONE; 676 677 musb_ep_select(mbase, 0); /* select ep0 */ 678 csr = musb_readw(regs, MUSB_CSR0); 679 len = musb_readb(regs, MUSB_COUNT0); 680 681 dev_dbg(musb->controller, "csr %04x, count %d, myaddr %d, ep0stage %s\n", 682 csr, len, 683 musb_readb(mbase, MUSB_FADDR), 684 decode_ep0stage(musb->ep0_state)); 685 686 /* I sent a stall.. need to acknowledge it now.. */ 687 if (csr & MUSB_CSR0_P_SENTSTALL) { 688 musb_writew(regs, MUSB_CSR0, 689 csr & ~MUSB_CSR0_P_SENTSTALL); 690 retval = IRQ_HANDLED; 691 musb->ep0_state = MUSB_EP0_STAGE_IDLE; 692 csr = musb_readw(regs, MUSB_CSR0); 693 } 694 695 /* request ended "early" */ 696 if (csr & MUSB_CSR0_P_SETUPEND) { 697 musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SVDSETUPEND); 698 retval = IRQ_HANDLED; 699 /* Transition into the early status phase */ 700 switch (musb->ep0_state) { 701 case MUSB_EP0_STAGE_TX: 702 musb->ep0_state = MUSB_EP0_STAGE_STATUSOUT; 703 break; 704 case MUSB_EP0_STAGE_RX: 705 musb->ep0_state = MUSB_EP0_STAGE_STATUSIN; 706 break; 707 default: 708 ERR("SetupEnd came in a wrong ep0stage %s\n", 709 decode_ep0stage(musb->ep0_state)); 710 } 711 csr = musb_readw(regs, MUSB_CSR0); 712 /* NOTE: request may need completion */ 713 } 714 715 /* docs from Mentor only describe tx, rx, and idle/setup states. 716 * we need to handle nuances around status stages, and also the 717 * case where status and setup stages come back-to-back ... 718 */ 719 switch (musb->ep0_state) { 720 721 case MUSB_EP0_STAGE_TX: 722 /* irq on clearing txpktrdy */ 723 if ((csr & MUSB_CSR0_TXPKTRDY) == 0) { 724 ep0_txstate(musb); 725 retval = IRQ_HANDLED; 726 } 727 break; 728 729 case MUSB_EP0_STAGE_RX: 730 /* irq on set rxpktrdy */ 731 if (csr & MUSB_CSR0_RXPKTRDY) { 732 ep0_rxstate(musb); 733 retval = IRQ_HANDLED; 734 } 735 break; 736 737 case MUSB_EP0_STAGE_STATUSIN: 738 /* end of sequence #2 (OUT/RX state) or #3 (no data) */ 739 740 /* update address (if needed) only @ the end of the 741 * status phase per usb spec, which also guarantees 742 * we get 10 msec to receive this irq... until this 743 * is done we won't see the next packet. 744 */ 745 if (musb->set_address) { 746 musb->set_address = false; 747 musb_writeb(mbase, MUSB_FADDR, musb->address); 748 } 749 750 /* enter test mode if needed (exit by reset) */ 751 else if (musb->test_mode) { 752 dev_dbg(musb->controller, "entering TESTMODE\n"); 753 754 if (MUSB_TEST_PACKET == musb->test_mode_nr) 755 musb_load_testpacket(musb); 756 757 musb_writeb(mbase, MUSB_TESTMODE, 758 musb->test_mode_nr); 759 } 760 /* FALLTHROUGH */ 761 762 case MUSB_EP0_STAGE_STATUSOUT: 763 /* end of sequence #1: write to host (TX state) */ 764 { 765 struct musb_request *req; 766 767 req = next_ep0_request(musb); 768 if (req) 769 musb_g_ep0_giveback(musb, &req->request); 770 } 771 772 /* 773 * In case when several interrupts can get coalesced, 774 * check to see if we've already received a SETUP packet... 775 */ 776 if (csr & MUSB_CSR0_RXPKTRDY) 777 goto setup; 778 779 retval = IRQ_HANDLED; 780 musb->ep0_state = MUSB_EP0_STAGE_IDLE; 781 break; 782 783 case MUSB_EP0_STAGE_IDLE: 784 /* 785 * This state is typically (but not always) indiscernible 786 * from the status states since the corresponding interrupts 787 * tend to happen within too little period of time (with only 788 * a zero-length packet in between) and so get coalesced... 789 */ 790 retval = IRQ_HANDLED; 791 musb->ep0_state = MUSB_EP0_STAGE_SETUP; 792 /* FALLTHROUGH */ 793 794 case MUSB_EP0_STAGE_SETUP: 795 setup: 796 if (csr & MUSB_CSR0_RXPKTRDY) { 797 struct usb_ctrlrequest setup; 798 int handled = 0; 799 800 if (len != 8) { 801 ERR("SETUP packet len %d != 8 ?\n", len); 802 break; 803 } 804 musb_read_setup(musb, &setup); 805 retval = IRQ_HANDLED; 806 807 /* sometimes the RESET won't be reported */ 808 if (unlikely(musb->g.speed == USB_SPEED_UNKNOWN)) { 809 u8 power; 810 811 printk(KERN_NOTICE "%s: peripheral reset " 812 "irq lost!\n", 813 musb_driver_name); 814 power = musb_readb(mbase, MUSB_POWER); 815 musb->g.speed = (power & MUSB_POWER_HSMODE) 816 ? USB_SPEED_HIGH : USB_SPEED_FULL; 817 818 } 819 820 switch (musb->ep0_state) { 821 822 /* sequence #3 (no data stage), includes requests 823 * we can't forward (notably SET_ADDRESS and the 824 * device/endpoint feature set/clear operations) 825 * plus SET_CONFIGURATION and others we must 826 */ 827 case MUSB_EP0_STAGE_ACKWAIT: 828 handled = service_zero_data_request( 829 musb, &setup); 830 831 /* 832 * We're expecting no data in any case, so 833 * always set the DATAEND bit -- doing this 834 * here helps avoid SetupEnd interrupt coming 835 * in the idle stage when we're stalling... 836 */ 837 musb->ackpend |= MUSB_CSR0_P_DATAEND; 838 839 /* status stage might be immediate */ 840 if (handled > 0) 841 musb->ep0_state = 842 MUSB_EP0_STAGE_STATUSIN; 843 break; 844 845 /* sequence #1 (IN to host), includes GET_STATUS 846 * requests that we can't forward, GET_DESCRIPTOR 847 * and others that we must 848 */ 849 case MUSB_EP0_STAGE_TX: 850 handled = service_in_request(musb, &setup); 851 if (handled > 0) { 852 musb->ackpend = MUSB_CSR0_TXPKTRDY 853 | MUSB_CSR0_P_DATAEND; 854 musb->ep0_state = 855 MUSB_EP0_STAGE_STATUSOUT; 856 } 857 break; 858 859 /* sequence #2 (OUT from host), always forward */ 860 default: /* MUSB_EP0_STAGE_RX */ 861 break; 862 } 863 864 dev_dbg(musb->controller, "handled %d, csr %04x, ep0stage %s\n", 865 handled, csr, 866 decode_ep0stage(musb->ep0_state)); 867 868 /* unless we need to delegate this to the gadget 869 * driver, we know how to wrap this up: csr0 has 870 * not yet been written. 871 */ 872 if (handled < 0) 873 goto stall; 874 else if (handled > 0) 875 goto finish; 876 877 handled = forward_to_driver(musb, &setup); 878 if (handled < 0) { 879 musb_ep_select(mbase, 0); 880 stall: 881 dev_dbg(musb->controller, "stall (%d)\n", handled); 882 musb->ackpend |= MUSB_CSR0_P_SENDSTALL; 883 musb->ep0_state = MUSB_EP0_STAGE_IDLE; 884 finish: 885 musb_writew(regs, MUSB_CSR0, 886 musb->ackpend); 887 musb->ackpend = 0; 888 } 889 } 890 break; 891 892 case MUSB_EP0_STAGE_ACKWAIT: 893 /* This should not happen. But happens with tusb6010 with 894 * g_file_storage and high speed. Do nothing. 895 */ 896 retval = IRQ_HANDLED; 897 break; 898 899 default: 900 /* "can't happen" */ 901 WARN_ON(1); 902 musb_writew(regs, MUSB_CSR0, MUSB_CSR0_P_SENDSTALL); 903 musb->ep0_state = MUSB_EP0_STAGE_IDLE; 904 break; 905 } 906 907 return retval; 908 } 909 910 911 static int 912 musb_g_ep0_enable(struct usb_ep *ep, const struct usb_endpoint_descriptor *desc) 913 { 914 /* always enabled */ 915 return -EINVAL; 916 } 917 918 static int musb_g_ep0_disable(struct usb_ep *e) 919 { 920 /* always enabled */ 921 return -EINVAL; 922 } 923 924 static int 925 musb_g_ep0_queue(struct usb_ep *e, struct usb_request *r, gfp_t gfp_flags) 926 { 927 struct musb_ep *ep; 928 struct musb_request *req; 929 struct musb *musb; 930 int status; 931 unsigned long lockflags; 932 void __iomem *regs; 933 934 if (!e || !r) 935 return -EINVAL; 936 937 ep = to_musb_ep(e); 938 musb = ep->musb; 939 regs = musb->control_ep->regs; 940 941 req = to_musb_request(r); 942 req->musb = musb; 943 req->request.actual = 0; 944 req->request.status = -EINPROGRESS; 945 req->tx = ep->is_in; 946 947 spin_lock_irqsave(&musb->lock, lockflags); 948 949 if (!list_empty(&ep->req_list)) { 950 status = -EBUSY; 951 goto cleanup; 952 } 953 954 switch (musb->ep0_state) { 955 case MUSB_EP0_STAGE_RX: /* control-OUT data */ 956 case MUSB_EP0_STAGE_TX: /* control-IN data */ 957 case MUSB_EP0_STAGE_ACKWAIT: /* zero-length data */ 958 status = 0; 959 break; 960 default: 961 dev_dbg(musb->controller, "ep0 request queued in state %d\n", 962 musb->ep0_state); 963 status = -EINVAL; 964 goto cleanup; 965 } 966 967 /* add request to the list */ 968 list_add_tail(&req->list, &ep->req_list); 969 970 dev_dbg(musb->controller, "queue to %s (%s), length=%d\n", 971 ep->name, ep->is_in ? "IN/TX" : "OUT/RX", 972 req->request.length); 973 974 musb_ep_select(musb->mregs, 0); 975 976 /* sequence #1, IN ... start writing the data */ 977 if (musb->ep0_state == MUSB_EP0_STAGE_TX) 978 ep0_txstate(musb); 979 980 /* sequence #3, no-data ... issue IN status */ 981 else if (musb->ep0_state == MUSB_EP0_STAGE_ACKWAIT) { 982 if (req->request.length) 983 status = -EINVAL; 984 else { 985 musb->ep0_state = MUSB_EP0_STAGE_STATUSIN; 986 musb_writew(regs, MUSB_CSR0, 987 musb->ackpend | MUSB_CSR0_P_DATAEND); 988 musb->ackpend = 0; 989 musb_g_ep0_giveback(ep->musb, r); 990 } 991 992 /* else for sequence #2 (OUT), caller provides a buffer 993 * before the next packet arrives. deferred responses 994 * (after SETUP is acked) are racey. 995 */ 996 } else if (musb->ackpend) { 997 musb_writew(regs, MUSB_CSR0, musb->ackpend); 998 musb->ackpend = 0; 999 } 1000 1001 cleanup: 1002 spin_unlock_irqrestore(&musb->lock, lockflags); 1003 return status; 1004 } 1005 1006 static int musb_g_ep0_dequeue(struct usb_ep *ep, struct usb_request *req) 1007 { 1008 /* we just won't support this */ 1009 return -EINVAL; 1010 } 1011 1012 static int musb_g_ep0_halt(struct usb_ep *e, int value) 1013 { 1014 struct musb_ep *ep; 1015 struct musb *musb; 1016 void __iomem *base, *regs; 1017 unsigned long flags; 1018 int status; 1019 u16 csr; 1020 1021 if (!e || !value) 1022 return -EINVAL; 1023 1024 ep = to_musb_ep(e); 1025 musb = ep->musb; 1026 base = musb->mregs; 1027 regs = musb->control_ep->regs; 1028 status = 0; 1029 1030 spin_lock_irqsave(&musb->lock, flags); 1031 1032 if (!list_empty(&ep->req_list)) { 1033 status = -EBUSY; 1034 goto cleanup; 1035 } 1036 1037 musb_ep_select(base, 0); 1038 csr = musb->ackpend; 1039 1040 switch (musb->ep0_state) { 1041 1042 /* Stalls are usually issued after parsing SETUP packet, either 1043 * directly in irq context from setup() or else later. 1044 */ 1045 case MUSB_EP0_STAGE_TX: /* control-IN data */ 1046 case MUSB_EP0_STAGE_ACKWAIT: /* STALL for zero-length data */ 1047 case MUSB_EP0_STAGE_RX: /* control-OUT data */ 1048 csr = musb_readw(regs, MUSB_CSR0); 1049 /* FALLTHROUGH */ 1050 1051 /* It's also OK to issue stalls during callbacks when a non-empty 1052 * DATA stage buffer has been read (or even written). 1053 */ 1054 case MUSB_EP0_STAGE_STATUSIN: /* control-OUT status */ 1055 case MUSB_EP0_STAGE_STATUSOUT: /* control-IN status */ 1056 1057 csr |= MUSB_CSR0_P_SENDSTALL; 1058 musb_writew(regs, MUSB_CSR0, csr); 1059 musb->ep0_state = MUSB_EP0_STAGE_IDLE; 1060 musb->ackpend = 0; 1061 break; 1062 default: 1063 dev_dbg(musb->controller, "ep0 can't halt in state %d\n", musb->ep0_state); 1064 status = -EINVAL; 1065 } 1066 1067 cleanup: 1068 spin_unlock_irqrestore(&musb->lock, flags); 1069 return status; 1070 } 1071 1072 const struct usb_ep_ops musb_g_ep0_ops = { 1073 .enable = musb_g_ep0_enable, 1074 .disable = musb_g_ep0_disable, 1075 .alloc_request = musb_alloc_request, 1076 .free_request = musb_free_request, 1077 .queue = musb_g_ep0_queue, 1078 .dequeue = musb_g_ep0_dequeue, 1079 .set_halt = musb_g_ep0_halt, 1080 }; 1081