1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * f_acm.c -- USB CDC serial (ACM) function driver 4 * 5 * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com) 6 * Copyright (C) 2008 by David Brownell 7 * Copyright (C) 2008 by Nokia Corporation 8 * Copyright (C) 2009 by Samsung Electronics 9 * Author: Michal Nazarewicz (mina86@mina86.com) 10 */ 11 12 /* #define VERBOSE_DEBUG */ 13 14 #include <linux/slab.h> 15 #include <linux/kernel.h> 16 #include <linux/module.h> 17 #include <linux/device.h> 18 #include <linux/err.h> 19 20 #include "u_serial.h" 21 22 23 /* 24 * This CDC ACM function support just wraps control functions and 25 * notifications around the generic serial-over-usb code. 26 * 27 * Because CDC ACM is standardized by the USB-IF, many host operating 28 * systems have drivers for it. Accordingly, ACM is the preferred 29 * interop solution for serial-port type connections. The control 30 * models are often not necessary, and in any case don't do much in 31 * this bare-bones implementation. 32 * 33 * Note that even MS-Windows has some support for ACM. However, that 34 * support is somewhat broken because when you use ACM in a composite 35 * device, having multiple interfaces confuses the poor OS. It doesn't 36 * seem to understand CDC Union descriptors. The new "association" 37 * descriptors (roughly equivalent to CDC Unions) may sometimes help. 38 */ 39 40 struct f_acm { 41 struct gserial port; 42 u8 ctrl_id, data_id; 43 u8 port_num; 44 u8 bInterfaceProtocol; 45 46 u8 pending; 47 48 /* lock is mostly for pending and notify_req ... they get accessed 49 * by callbacks both from tty (open/close/break) under its spinlock, 50 * and notify_req.complete() which can't use that lock. 51 */ 52 spinlock_t lock; 53 54 struct usb_ep *notify; 55 struct usb_request *notify_req; 56 57 struct usb_cdc_line_coding port_line_coding; /* 8-N-1 etc */ 58 59 /* SetControlLineState request -- CDC 1.1 section 6.2.14 (INPUT) */ 60 u16 port_handshake_bits; 61 /* SerialState notification -- CDC 1.1 section 6.3.5 (OUTPUT) */ 62 u16 serial_state; 63 }; 64 65 static inline struct f_acm *func_to_acm(struct usb_function *f) 66 { 67 return container_of(f, struct f_acm, port.func); 68 } 69 70 static inline struct f_acm *port_to_acm(struct gserial *p) 71 { 72 return container_of(p, struct f_acm, port); 73 } 74 75 /*-------------------------------------------------------------------------*/ 76 77 /* notification endpoint uses smallish and infrequent fixed-size messages */ 78 79 #define GS_NOTIFY_INTERVAL_MS 32 80 #define GS_NOTIFY_MAXPACKET 10 /* notification + 2 bytes */ 81 82 /* interface and class descriptors: */ 83 84 static struct usb_interface_assoc_descriptor 85 acm_iad_descriptor = { 86 .bLength = sizeof acm_iad_descriptor, 87 .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION, 88 89 /* .bFirstInterface = DYNAMIC, */ 90 .bInterfaceCount = 2, // control + data 91 .bFunctionClass = USB_CLASS_COMM, 92 .bFunctionSubClass = USB_CDC_SUBCLASS_ACM, 93 /* .bFunctionProtocol = DYNAMIC */ 94 /* .iFunction = DYNAMIC */ 95 }; 96 97 98 static struct usb_interface_descriptor acm_control_interface_desc = { 99 .bLength = USB_DT_INTERFACE_SIZE, 100 .bDescriptorType = USB_DT_INTERFACE, 101 /* .bInterfaceNumber = DYNAMIC */ 102 .bNumEndpoints = 1, 103 .bInterfaceClass = USB_CLASS_COMM, 104 .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM, 105 /* .bInterfaceProtocol = DYNAMIC */ 106 /* .iInterface = DYNAMIC */ 107 }; 108 109 static struct usb_interface_descriptor acm_data_interface_desc = { 110 .bLength = USB_DT_INTERFACE_SIZE, 111 .bDescriptorType = USB_DT_INTERFACE, 112 /* .bInterfaceNumber = DYNAMIC */ 113 .bNumEndpoints = 2, 114 .bInterfaceClass = USB_CLASS_CDC_DATA, 115 .bInterfaceSubClass = 0, 116 .bInterfaceProtocol = 0, 117 /* .iInterface = DYNAMIC */ 118 }; 119 120 static struct usb_cdc_header_desc acm_header_desc = { 121 .bLength = sizeof(acm_header_desc), 122 .bDescriptorType = USB_DT_CS_INTERFACE, 123 .bDescriptorSubType = USB_CDC_HEADER_TYPE, 124 .bcdCDC = cpu_to_le16(0x0110), 125 }; 126 127 static struct usb_cdc_call_mgmt_descriptor 128 acm_call_mgmt_descriptor = { 129 .bLength = sizeof(acm_call_mgmt_descriptor), 130 .bDescriptorType = USB_DT_CS_INTERFACE, 131 .bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE, 132 .bmCapabilities = 0, 133 /* .bDataInterface = DYNAMIC */ 134 }; 135 136 static struct usb_cdc_acm_descriptor acm_descriptor = { 137 .bLength = sizeof(acm_descriptor), 138 .bDescriptorType = USB_DT_CS_INTERFACE, 139 .bDescriptorSubType = USB_CDC_ACM_TYPE, 140 .bmCapabilities = USB_CDC_CAP_LINE, 141 }; 142 143 static struct usb_cdc_union_desc acm_union_desc = { 144 .bLength = sizeof(acm_union_desc), 145 .bDescriptorType = USB_DT_CS_INTERFACE, 146 .bDescriptorSubType = USB_CDC_UNION_TYPE, 147 /* .bMasterInterface0 = DYNAMIC */ 148 /* .bSlaveInterface0 = DYNAMIC */ 149 }; 150 151 /* full speed support: */ 152 153 static struct usb_endpoint_descriptor acm_fs_notify_desc = { 154 .bLength = USB_DT_ENDPOINT_SIZE, 155 .bDescriptorType = USB_DT_ENDPOINT, 156 .bEndpointAddress = USB_DIR_IN, 157 .bmAttributes = USB_ENDPOINT_XFER_INT, 158 .wMaxPacketSize = cpu_to_le16(GS_NOTIFY_MAXPACKET), 159 .bInterval = GS_NOTIFY_INTERVAL_MS, 160 }; 161 162 static struct usb_endpoint_descriptor acm_fs_in_desc = { 163 .bLength = USB_DT_ENDPOINT_SIZE, 164 .bDescriptorType = USB_DT_ENDPOINT, 165 .bEndpointAddress = USB_DIR_IN, 166 .bmAttributes = USB_ENDPOINT_XFER_BULK, 167 }; 168 169 static struct usb_endpoint_descriptor acm_fs_out_desc = { 170 .bLength = USB_DT_ENDPOINT_SIZE, 171 .bDescriptorType = USB_DT_ENDPOINT, 172 .bEndpointAddress = USB_DIR_OUT, 173 .bmAttributes = USB_ENDPOINT_XFER_BULK, 174 }; 175 176 static struct usb_descriptor_header *acm_fs_function[] = { 177 (struct usb_descriptor_header *) &acm_iad_descriptor, 178 (struct usb_descriptor_header *) &acm_control_interface_desc, 179 (struct usb_descriptor_header *) &acm_header_desc, 180 (struct usb_descriptor_header *) &acm_call_mgmt_descriptor, 181 (struct usb_descriptor_header *) &acm_descriptor, 182 (struct usb_descriptor_header *) &acm_union_desc, 183 (struct usb_descriptor_header *) &acm_fs_notify_desc, 184 (struct usb_descriptor_header *) &acm_data_interface_desc, 185 (struct usb_descriptor_header *) &acm_fs_in_desc, 186 (struct usb_descriptor_header *) &acm_fs_out_desc, 187 NULL, 188 }; 189 190 /* high speed support: */ 191 static struct usb_endpoint_descriptor acm_hs_notify_desc = { 192 .bLength = USB_DT_ENDPOINT_SIZE, 193 .bDescriptorType = USB_DT_ENDPOINT, 194 .bEndpointAddress = USB_DIR_IN, 195 .bmAttributes = USB_ENDPOINT_XFER_INT, 196 .wMaxPacketSize = cpu_to_le16(GS_NOTIFY_MAXPACKET), 197 .bInterval = USB_MS_TO_HS_INTERVAL(GS_NOTIFY_INTERVAL_MS), 198 }; 199 200 static struct usb_endpoint_descriptor acm_hs_in_desc = { 201 .bLength = USB_DT_ENDPOINT_SIZE, 202 .bDescriptorType = USB_DT_ENDPOINT, 203 .bmAttributes = USB_ENDPOINT_XFER_BULK, 204 .wMaxPacketSize = cpu_to_le16(512), 205 }; 206 207 static struct usb_endpoint_descriptor acm_hs_out_desc = { 208 .bLength = USB_DT_ENDPOINT_SIZE, 209 .bDescriptorType = USB_DT_ENDPOINT, 210 .bmAttributes = USB_ENDPOINT_XFER_BULK, 211 .wMaxPacketSize = cpu_to_le16(512), 212 }; 213 214 static struct usb_descriptor_header *acm_hs_function[] = { 215 (struct usb_descriptor_header *) &acm_iad_descriptor, 216 (struct usb_descriptor_header *) &acm_control_interface_desc, 217 (struct usb_descriptor_header *) &acm_header_desc, 218 (struct usb_descriptor_header *) &acm_call_mgmt_descriptor, 219 (struct usb_descriptor_header *) &acm_descriptor, 220 (struct usb_descriptor_header *) &acm_union_desc, 221 (struct usb_descriptor_header *) &acm_hs_notify_desc, 222 (struct usb_descriptor_header *) &acm_data_interface_desc, 223 (struct usb_descriptor_header *) &acm_hs_in_desc, 224 (struct usb_descriptor_header *) &acm_hs_out_desc, 225 NULL, 226 }; 227 228 static struct usb_endpoint_descriptor acm_ss_in_desc = { 229 .bLength = USB_DT_ENDPOINT_SIZE, 230 .bDescriptorType = USB_DT_ENDPOINT, 231 .bmAttributes = USB_ENDPOINT_XFER_BULK, 232 .wMaxPacketSize = cpu_to_le16(1024), 233 }; 234 235 static struct usb_endpoint_descriptor acm_ss_out_desc = { 236 .bLength = USB_DT_ENDPOINT_SIZE, 237 .bDescriptorType = USB_DT_ENDPOINT, 238 .bmAttributes = USB_ENDPOINT_XFER_BULK, 239 .wMaxPacketSize = cpu_to_le16(1024), 240 }; 241 242 static struct usb_ss_ep_comp_descriptor acm_ss_bulk_comp_desc = { 243 .bLength = sizeof acm_ss_bulk_comp_desc, 244 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 245 }; 246 247 static struct usb_descriptor_header *acm_ss_function[] = { 248 (struct usb_descriptor_header *) &acm_iad_descriptor, 249 (struct usb_descriptor_header *) &acm_control_interface_desc, 250 (struct usb_descriptor_header *) &acm_header_desc, 251 (struct usb_descriptor_header *) &acm_call_mgmt_descriptor, 252 (struct usb_descriptor_header *) &acm_descriptor, 253 (struct usb_descriptor_header *) &acm_union_desc, 254 (struct usb_descriptor_header *) &acm_hs_notify_desc, 255 (struct usb_descriptor_header *) &acm_ss_bulk_comp_desc, 256 (struct usb_descriptor_header *) &acm_data_interface_desc, 257 (struct usb_descriptor_header *) &acm_ss_in_desc, 258 (struct usb_descriptor_header *) &acm_ss_bulk_comp_desc, 259 (struct usb_descriptor_header *) &acm_ss_out_desc, 260 (struct usb_descriptor_header *) &acm_ss_bulk_comp_desc, 261 NULL, 262 }; 263 264 /* string descriptors: */ 265 266 #define ACM_CTRL_IDX 0 267 #define ACM_DATA_IDX 1 268 #define ACM_IAD_IDX 2 269 270 /* static strings, in UTF-8 */ 271 static struct usb_string acm_string_defs[] = { 272 [ACM_CTRL_IDX].s = "CDC Abstract Control Model (ACM)", 273 [ACM_DATA_IDX].s = "CDC ACM Data", 274 [ACM_IAD_IDX ].s = "CDC Serial", 275 { } /* end of list */ 276 }; 277 278 static struct usb_gadget_strings acm_string_table = { 279 .language = 0x0409, /* en-us */ 280 .strings = acm_string_defs, 281 }; 282 283 static struct usb_gadget_strings *acm_strings[] = { 284 &acm_string_table, 285 NULL, 286 }; 287 288 /*-------------------------------------------------------------------------*/ 289 290 /* ACM control ... data handling is delegated to tty library code. 291 * The main task of this function is to activate and deactivate 292 * that code based on device state; track parameters like line 293 * speed, handshake state, and so on; and issue notifications. 294 */ 295 296 static void acm_complete_set_line_coding(struct usb_ep *ep, 297 struct usb_request *req) 298 { 299 struct f_acm *acm = ep->driver_data; 300 struct usb_composite_dev *cdev = acm->port.func.config->cdev; 301 302 if (req->status != 0) { 303 dev_dbg(&cdev->gadget->dev, "acm ttyGS%d completion, err %d\n", 304 acm->port_num, req->status); 305 return; 306 } 307 308 /* normal completion */ 309 if (req->actual != sizeof(acm->port_line_coding)) { 310 dev_dbg(&cdev->gadget->dev, "acm ttyGS%d short resp, len %d\n", 311 acm->port_num, req->actual); 312 usb_ep_set_halt(ep); 313 } else { 314 struct usb_cdc_line_coding *value = req->buf; 315 316 /* REVISIT: we currently just remember this data. 317 * If we change that, (a) validate it first, then 318 * (b) update whatever hardware needs updating, 319 * (c) worry about locking. This is information on 320 * the order of 9600-8-N-1 ... most of which means 321 * nothing unless we control a real RS232 line. 322 */ 323 acm->port_line_coding = *value; 324 } 325 } 326 327 static int acm_send_break(struct gserial *port, int duration); 328 329 static int acm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) 330 { 331 struct f_acm *acm = func_to_acm(f); 332 struct usb_composite_dev *cdev = f->config->cdev; 333 struct usb_request *req = cdev->req; 334 int value = -EOPNOTSUPP; 335 u16 w_index = le16_to_cpu(ctrl->wIndex); 336 u16 w_value = le16_to_cpu(ctrl->wValue); 337 u16 w_length = le16_to_cpu(ctrl->wLength); 338 339 /* composite driver infrastructure handles everything except 340 * CDC class messages; interface activation uses set_alt(). 341 * 342 * Note CDC spec table 4 lists the ACM request profile. It requires 343 * encapsulated command support ... we don't handle any, and respond 344 * to them by stalling. Options include get/set/clear comm features 345 * (not that useful) and SEND_BREAK. 346 */ 347 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) { 348 349 /* SET_LINE_CODING ... just read and save what the host sends */ 350 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 351 | USB_CDC_REQ_SET_LINE_CODING: 352 if (w_length != sizeof(struct usb_cdc_line_coding) 353 || w_index != acm->ctrl_id) 354 goto invalid; 355 356 value = w_length; 357 cdev->gadget->ep0->driver_data = acm; 358 req->complete = acm_complete_set_line_coding; 359 break; 360 361 /* GET_LINE_CODING ... return what host sent, or initial value */ 362 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 363 | USB_CDC_REQ_GET_LINE_CODING: 364 if (w_index != acm->ctrl_id) 365 goto invalid; 366 367 value = min_t(unsigned, w_length, 368 sizeof(struct usb_cdc_line_coding)); 369 memcpy(req->buf, &acm->port_line_coding, value); 370 break; 371 372 /* SET_CONTROL_LINE_STATE ... save what the host sent */ 373 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 374 | USB_CDC_REQ_SET_CONTROL_LINE_STATE: 375 if (w_index != acm->ctrl_id) 376 goto invalid; 377 378 value = 0; 379 380 /* FIXME we should not allow data to flow until the 381 * host sets the USB_CDC_CTRL_DTR bit; and when it clears 382 * that bit, we should return to that no-flow state. 383 */ 384 acm->port_handshake_bits = w_value; 385 break; 386 387 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 388 | USB_CDC_REQ_SEND_BREAK: 389 if (w_index != acm->ctrl_id) 390 goto invalid; 391 392 acm_send_break(&acm->port, w_value); 393 break; 394 395 default: 396 invalid: 397 dev_vdbg(&cdev->gadget->dev, 398 "invalid control req%02x.%02x v%04x i%04x l%d\n", 399 ctrl->bRequestType, ctrl->bRequest, 400 w_value, w_index, w_length); 401 } 402 403 /* respond with data transfer or status phase? */ 404 if (value >= 0) { 405 dev_dbg(&cdev->gadget->dev, 406 "acm ttyGS%d req%02x.%02x v%04x i%04x l%d\n", 407 acm->port_num, ctrl->bRequestType, ctrl->bRequest, 408 w_value, w_index, w_length); 409 req->zero = 0; 410 req->length = value; 411 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); 412 if (value < 0) 413 ERROR(cdev, "acm response on ttyGS%d, err %d\n", 414 acm->port_num, value); 415 } 416 417 /* device either stalls (value < 0) or reports success */ 418 return value; 419 } 420 421 static int acm_set_alt(struct usb_function *f, unsigned intf, unsigned alt) 422 { 423 struct f_acm *acm = func_to_acm(f); 424 struct usb_composite_dev *cdev = f->config->cdev; 425 426 /* we know alt == 0, so this is an activation or a reset */ 427 428 if (intf == acm->ctrl_id) { 429 if (acm->notify->enabled) { 430 dev_vdbg(&cdev->gadget->dev, 431 "reset acm control interface %d\n", intf); 432 usb_ep_disable(acm->notify); 433 } 434 435 if (!acm->notify->desc) 436 if (config_ep_by_speed(cdev->gadget, f, acm->notify)) 437 return -EINVAL; 438 439 usb_ep_enable(acm->notify); 440 441 } else if (intf == acm->data_id) { 442 if (acm->notify->enabled) { 443 dev_dbg(&cdev->gadget->dev, 444 "reset acm ttyGS%d\n", acm->port_num); 445 gserial_disconnect(&acm->port); 446 } 447 if (!acm->port.in->desc || !acm->port.out->desc) { 448 dev_dbg(&cdev->gadget->dev, 449 "activate acm ttyGS%d\n", acm->port_num); 450 if (config_ep_by_speed(cdev->gadget, f, 451 acm->port.in) || 452 config_ep_by_speed(cdev->gadget, f, 453 acm->port.out)) { 454 acm->port.in->desc = NULL; 455 acm->port.out->desc = NULL; 456 return -EINVAL; 457 } 458 } 459 gserial_connect(&acm->port, acm->port_num); 460 461 } else 462 return -EINVAL; 463 464 return 0; 465 } 466 467 static void acm_disable(struct usb_function *f) 468 { 469 struct f_acm *acm = func_to_acm(f); 470 struct usb_composite_dev *cdev = f->config->cdev; 471 472 dev_dbg(&cdev->gadget->dev, "acm ttyGS%d deactivated\n", acm->port_num); 473 gserial_disconnect(&acm->port); 474 usb_ep_disable(acm->notify); 475 } 476 477 /*-------------------------------------------------------------------------*/ 478 479 /** 480 * acm_cdc_notify - issue CDC notification to host 481 * @acm: wraps host to be notified 482 * @type: notification type 483 * @value: Refer to cdc specs, wValue field. 484 * @data: data to be sent 485 * @length: size of data 486 * Context: irqs blocked, acm->lock held, acm_notify_req non-null 487 * 488 * Returns zero on success or a negative errno. 489 * 490 * See section 6.3.5 of the CDC 1.1 specification for information 491 * about the only notification we issue: SerialState change. 492 */ 493 static int acm_cdc_notify(struct f_acm *acm, u8 type, u16 value, 494 void *data, unsigned length) 495 { 496 struct usb_ep *ep = acm->notify; 497 struct usb_request *req; 498 struct usb_cdc_notification *notify; 499 const unsigned len = sizeof(*notify) + length; 500 void *buf; 501 int status; 502 503 req = acm->notify_req; 504 acm->notify_req = NULL; 505 acm->pending = false; 506 507 req->length = len; 508 notify = req->buf; 509 buf = notify + 1; 510 511 notify->bmRequestType = USB_DIR_IN | USB_TYPE_CLASS 512 | USB_RECIP_INTERFACE; 513 notify->bNotificationType = type; 514 notify->wValue = cpu_to_le16(value); 515 notify->wIndex = cpu_to_le16(acm->ctrl_id); 516 notify->wLength = cpu_to_le16(length); 517 memcpy(buf, data, length); 518 519 /* ep_queue() can complete immediately if it fills the fifo... */ 520 spin_unlock(&acm->lock); 521 status = usb_ep_queue(ep, req, GFP_ATOMIC); 522 spin_lock(&acm->lock); 523 524 if (status < 0) { 525 ERROR(acm->port.func.config->cdev, 526 "acm ttyGS%d can't notify serial state, %d\n", 527 acm->port_num, status); 528 acm->notify_req = req; 529 } 530 531 return status; 532 } 533 534 static int acm_notify_serial_state(struct f_acm *acm) 535 { 536 struct usb_composite_dev *cdev = acm->port.func.config->cdev; 537 int status; 538 __le16 serial_state; 539 540 spin_lock(&acm->lock); 541 if (acm->notify_req) { 542 dev_dbg(&cdev->gadget->dev, "acm ttyGS%d serial state %04x\n", 543 acm->port_num, acm->serial_state); 544 serial_state = cpu_to_le16(acm->serial_state); 545 status = acm_cdc_notify(acm, USB_CDC_NOTIFY_SERIAL_STATE, 546 0, &serial_state, sizeof(acm->serial_state)); 547 } else { 548 acm->pending = true; 549 status = 0; 550 } 551 spin_unlock(&acm->lock); 552 return status; 553 } 554 555 static void acm_cdc_notify_complete(struct usb_ep *ep, struct usb_request *req) 556 { 557 struct f_acm *acm = req->context; 558 u8 doit = false; 559 560 /* on this call path we do NOT hold the port spinlock, 561 * which is why ACM needs its own spinlock 562 */ 563 spin_lock(&acm->lock); 564 if (req->status != -ESHUTDOWN) 565 doit = acm->pending; 566 acm->notify_req = req; 567 spin_unlock(&acm->lock); 568 569 if (doit) 570 acm_notify_serial_state(acm); 571 } 572 573 /* connect == the TTY link is open */ 574 575 static void acm_connect(struct gserial *port) 576 { 577 struct f_acm *acm = port_to_acm(port); 578 579 acm->serial_state |= USB_CDC_SERIAL_STATE_DSR | USB_CDC_SERIAL_STATE_DCD; 580 acm_notify_serial_state(acm); 581 } 582 583 static void acm_disconnect(struct gserial *port) 584 { 585 struct f_acm *acm = port_to_acm(port); 586 587 acm->serial_state &= ~(USB_CDC_SERIAL_STATE_DSR | USB_CDC_SERIAL_STATE_DCD); 588 acm_notify_serial_state(acm); 589 } 590 591 static int acm_send_break(struct gserial *port, int duration) 592 { 593 struct f_acm *acm = port_to_acm(port); 594 u16 state; 595 596 state = acm->serial_state; 597 state &= ~USB_CDC_SERIAL_STATE_BREAK; 598 if (duration) 599 state |= USB_CDC_SERIAL_STATE_BREAK; 600 601 acm->serial_state = state; 602 return acm_notify_serial_state(acm); 603 } 604 605 /*-------------------------------------------------------------------------*/ 606 607 /* ACM function driver setup/binding */ 608 static int 609 acm_bind(struct usb_configuration *c, struct usb_function *f) 610 { 611 struct usb_composite_dev *cdev = c->cdev; 612 struct f_acm *acm = func_to_acm(f); 613 struct usb_string *us; 614 int status; 615 struct usb_ep *ep; 616 617 /* REVISIT might want instance-specific strings to help 618 * distinguish instances ... 619 */ 620 621 /* maybe allocate device-global string IDs, and patch descriptors */ 622 us = usb_gstrings_attach(cdev, acm_strings, 623 ARRAY_SIZE(acm_string_defs)); 624 if (IS_ERR(us)) 625 return PTR_ERR(us); 626 acm_control_interface_desc.iInterface = us[ACM_CTRL_IDX].id; 627 acm_data_interface_desc.iInterface = us[ACM_DATA_IDX].id; 628 acm_iad_descriptor.iFunction = us[ACM_IAD_IDX].id; 629 630 /* allocate instance-specific interface IDs, and patch descriptors */ 631 status = usb_interface_id(c, f); 632 if (status < 0) 633 goto fail; 634 acm->ctrl_id = status; 635 acm_iad_descriptor.bFirstInterface = status; 636 637 acm_control_interface_desc.bInterfaceNumber = status; 638 acm_union_desc .bMasterInterface0 = status; 639 640 status = usb_interface_id(c, f); 641 if (status < 0) 642 goto fail; 643 acm->data_id = status; 644 645 acm_data_interface_desc.bInterfaceNumber = status; 646 acm_union_desc.bSlaveInterface0 = status; 647 acm_call_mgmt_descriptor.bDataInterface = status; 648 649 status = -ENODEV; 650 651 /* allocate instance-specific endpoints */ 652 ep = usb_ep_autoconfig(cdev->gadget, &acm_fs_in_desc); 653 if (!ep) 654 goto fail; 655 acm->port.in = ep; 656 657 ep = usb_ep_autoconfig(cdev->gadget, &acm_fs_out_desc); 658 if (!ep) 659 goto fail; 660 acm->port.out = ep; 661 662 ep = usb_ep_autoconfig(cdev->gadget, &acm_fs_notify_desc); 663 if (!ep) 664 goto fail; 665 acm->notify = ep; 666 667 acm_iad_descriptor.bFunctionProtocol = acm->bInterfaceProtocol; 668 acm_control_interface_desc.bInterfaceProtocol = acm->bInterfaceProtocol; 669 670 /* allocate notification */ 671 acm->notify_req = gs_alloc_req(ep, 672 sizeof(struct usb_cdc_notification) + 2, 673 GFP_KERNEL); 674 if (!acm->notify_req) 675 goto fail; 676 677 acm->notify_req->complete = acm_cdc_notify_complete; 678 acm->notify_req->context = acm; 679 680 /* support all relevant hardware speeds... we expect that when 681 * hardware is dual speed, all bulk-capable endpoints work at 682 * both speeds 683 */ 684 acm_hs_in_desc.bEndpointAddress = acm_fs_in_desc.bEndpointAddress; 685 acm_hs_out_desc.bEndpointAddress = acm_fs_out_desc.bEndpointAddress; 686 acm_hs_notify_desc.bEndpointAddress = 687 acm_fs_notify_desc.bEndpointAddress; 688 689 acm_ss_in_desc.bEndpointAddress = acm_fs_in_desc.bEndpointAddress; 690 acm_ss_out_desc.bEndpointAddress = acm_fs_out_desc.bEndpointAddress; 691 692 status = usb_assign_descriptors(f, acm_fs_function, acm_hs_function, 693 acm_ss_function, acm_ss_function); 694 if (status) 695 goto fail; 696 697 dev_dbg(&cdev->gadget->dev, 698 "acm ttyGS%d: IN/%s OUT/%s NOTIFY/%s\n", 699 acm->port_num, 700 acm->port.in->name, acm->port.out->name, 701 acm->notify->name); 702 return 0; 703 704 fail: 705 if (acm->notify_req) 706 gs_free_req(acm->notify, acm->notify_req); 707 708 ERROR(cdev, "%s/%p: can't bind, err %d\n", f->name, f, status); 709 710 return status; 711 } 712 713 static void acm_unbind(struct usb_configuration *c, struct usb_function *f) 714 { 715 struct f_acm *acm = func_to_acm(f); 716 717 acm_string_defs[0].id = 0; 718 usb_free_all_descriptors(f); 719 if (acm->notify_req) 720 gs_free_req(acm->notify, acm->notify_req); 721 } 722 723 static void acm_free_func(struct usb_function *f) 724 { 725 struct f_acm *acm = func_to_acm(f); 726 struct f_serial_opts *opts; 727 728 opts = container_of(f->fi, struct f_serial_opts, func_inst); 729 730 kfree(acm); 731 mutex_lock(&opts->lock); 732 opts->instances--; 733 mutex_unlock(&opts->lock); 734 } 735 736 static void acm_resume(struct usb_function *f) 737 { 738 struct f_acm *acm = func_to_acm(f); 739 740 gserial_resume(&acm->port); 741 } 742 743 static void acm_suspend(struct usb_function *f) 744 { 745 struct f_acm *acm = func_to_acm(f); 746 747 gserial_suspend(&acm->port); 748 } 749 750 static struct usb_function *acm_alloc_func(struct usb_function_instance *fi) 751 { 752 struct f_serial_opts *opts; 753 struct f_acm *acm; 754 755 acm = kzalloc(sizeof(*acm), GFP_KERNEL); 756 if (!acm) 757 return ERR_PTR(-ENOMEM); 758 759 spin_lock_init(&acm->lock); 760 761 acm->port.connect = acm_connect; 762 acm->port.disconnect = acm_disconnect; 763 acm->port.send_break = acm_send_break; 764 765 acm->port.func.name = "acm"; 766 acm->port.func.strings = acm_strings; 767 /* descriptors are per-instance copies */ 768 acm->port.func.bind = acm_bind; 769 acm->port.func.set_alt = acm_set_alt; 770 acm->port.func.setup = acm_setup; 771 acm->port.func.disable = acm_disable; 772 773 opts = container_of(fi, struct f_serial_opts, func_inst); 774 mutex_lock(&opts->lock); 775 acm->port_num = opts->port_num; 776 acm->bInterfaceProtocol = opts->protocol; 777 opts->instances++; 778 mutex_unlock(&opts->lock); 779 acm->port.func.unbind = acm_unbind; 780 acm->port.func.free_func = acm_free_func; 781 acm->port.func.resume = acm_resume; 782 acm->port.func.suspend = acm_suspend; 783 784 return &acm->port.func; 785 } 786 787 static inline struct f_serial_opts *to_f_serial_opts(struct config_item *item) 788 { 789 return container_of(to_config_group(item), struct f_serial_opts, 790 func_inst.group); 791 } 792 793 static void acm_attr_release(struct config_item *item) 794 { 795 struct f_serial_opts *opts = to_f_serial_opts(item); 796 797 usb_put_function_instance(&opts->func_inst); 798 } 799 800 static struct configfs_item_operations acm_item_ops = { 801 .release = acm_attr_release, 802 }; 803 804 #ifdef CONFIG_U_SERIAL_CONSOLE 805 806 static ssize_t f_acm_console_store(struct config_item *item, 807 const char *page, size_t count) 808 { 809 return gserial_set_console(to_f_serial_opts(item)->port_num, 810 page, count); 811 } 812 813 static ssize_t f_acm_console_show(struct config_item *item, char *page) 814 { 815 return gserial_get_console(to_f_serial_opts(item)->port_num, page); 816 } 817 818 CONFIGFS_ATTR(f_acm_, console); 819 820 #endif /* CONFIG_U_SERIAL_CONSOLE */ 821 822 static ssize_t f_acm_port_num_show(struct config_item *item, char *page) 823 { 824 return sprintf(page, "%u\n", to_f_serial_opts(item)->port_num); 825 } 826 827 CONFIGFS_ATTR_RO(f_acm_, port_num); 828 829 static ssize_t f_acm_protocol_show(struct config_item *item, char *page) 830 { 831 return sprintf(page, "%u\n", to_f_serial_opts(item)->protocol); 832 } 833 834 static ssize_t f_acm_protocol_store(struct config_item *item, 835 const char *page, size_t count) 836 { 837 struct f_serial_opts *opts = to_f_serial_opts(item); 838 int ret; 839 840 mutex_lock(&opts->lock); 841 842 if (opts->instances) { 843 ret = -EBUSY; 844 goto out; 845 } 846 847 ret = kstrtou8(page, 0, &opts->protocol); 848 if (ret) 849 goto out; 850 ret = count; 851 852 out: 853 mutex_unlock(&opts->lock); 854 return ret; 855 } 856 857 CONFIGFS_ATTR(f_acm_, protocol); 858 859 static struct configfs_attribute *acm_attrs[] = { 860 #ifdef CONFIG_U_SERIAL_CONSOLE 861 &f_acm_attr_console, 862 #endif 863 &f_acm_attr_port_num, 864 &f_acm_attr_protocol, 865 NULL, 866 }; 867 868 static const struct config_item_type acm_func_type = { 869 .ct_item_ops = &acm_item_ops, 870 .ct_attrs = acm_attrs, 871 .ct_owner = THIS_MODULE, 872 }; 873 874 static void acm_free_instance(struct usb_function_instance *fi) 875 { 876 struct f_serial_opts *opts; 877 878 opts = container_of(fi, struct f_serial_opts, func_inst); 879 gserial_free_line(opts->port_num); 880 mutex_destroy(&opts->lock); 881 kfree(opts); 882 } 883 884 static struct usb_function_instance *acm_alloc_instance(void) 885 { 886 struct f_serial_opts *opts; 887 int ret; 888 889 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 890 if (!opts) 891 return ERR_PTR(-ENOMEM); 892 opts->protocol = USB_CDC_ACM_PROTO_AT_V25TER; 893 opts->func_inst.free_func_inst = acm_free_instance; 894 mutex_init(&opts->lock); 895 ret = gserial_alloc_line(&opts->port_num); 896 if (ret) { 897 kfree(opts); 898 return ERR_PTR(ret); 899 } 900 config_group_init_type_name(&opts->func_inst.group, "", 901 &acm_func_type); 902 return &opts->func_inst; 903 } 904 DECLARE_USB_FUNCTION_INIT(acm, acm_alloc_instance, acm_alloc_func); 905 MODULE_DESCRIPTION("USB CDC serial (ACM) function driver"); 906 MODULE_LICENSE("GPL"); 907