1 /* 2 * Surface2.0/SUR40/PixelSense input driver 3 * 4 * Copyright (c) 2014 by Florian 'floe' Echtler <floe@butterbrot.org> 5 * 6 * Derived from the USB Skeleton driver 1.1, 7 * Copyright (c) 2003 Greg Kroah-Hartman (greg@kroah.com) 8 * 9 * and from the Apple USB BCM5974 multitouch driver, 10 * Copyright (c) 2008 Henrik Rydberg (rydberg@euromail.se) 11 * 12 * and from the generic hid-multitouch driver, 13 * Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr> 14 * 15 * and from the v4l2-pci-skeleton driver, 16 * Copyright (c) Copyright 2014 Cisco Systems, Inc. 17 * 18 * This program is free software; you can redistribute it and/or 19 * modify it under the terms of the GNU General Public License as 20 * published by the Free Software Foundation; either version 2 of 21 * the License, or (at your option) any later version. 22 */ 23 24 #include <linux/kernel.h> 25 #include <linux/errno.h> 26 #include <linux/delay.h> 27 #include <linux/init.h> 28 #include <linux/slab.h> 29 #include <linux/module.h> 30 #include <linux/completion.h> 31 #include <linux/uaccess.h> 32 #include <linux/usb.h> 33 #include <linux/printk.h> 34 #include <linux/input-polldev.h> 35 #include <linux/input/mt.h> 36 #include <linux/usb/input.h> 37 #include <linux/videodev2.h> 38 #include <media/v4l2-device.h> 39 #include <media/v4l2-dev.h> 40 #include <media/v4l2-ioctl.h> 41 #include <media/videobuf2-dma-sg.h> 42 43 /* read 512 bytes from endpoint 0x86 -> get header + blobs */ 44 struct sur40_header { 45 46 __le16 type; /* always 0x0001 */ 47 __le16 count; /* count of blobs (if 0: continue prev. packet) */ 48 49 __le32 packet_id; /* unique ID for all packets in one frame */ 50 51 __le32 timestamp; /* milliseconds (inc. by 16 or 17 each frame) */ 52 __le32 unknown; /* "epoch?" always 02/03 00 00 00 */ 53 54 } __packed; 55 56 struct sur40_blob { 57 58 __le16 blob_id; 59 60 u8 action; /* 0x02 = enter/exit, 0x03 = update (?) */ 61 u8 unknown; /* always 0x01 or 0x02 (no idea what this is?) */ 62 63 __le16 bb_pos_x; /* upper left corner of bounding box */ 64 __le16 bb_pos_y; 65 66 __le16 bb_size_x; /* size of bounding box */ 67 __le16 bb_size_y; 68 69 __le16 pos_x; /* finger tip position */ 70 __le16 pos_y; 71 72 __le16 ctr_x; /* centroid position */ 73 __le16 ctr_y; 74 75 __le16 axis_x; /* somehow related to major/minor axis, mostly: */ 76 __le16 axis_y; /* axis_x == bb_size_y && axis_y == bb_size_x */ 77 78 __le32 angle; /* orientation in radians relative to x axis - 79 actually an IEEE754 float, don't use in kernel */ 80 81 __le32 area; /* size in pixels/pressure (?) */ 82 83 u8 padding[32]; 84 85 } __packed; 86 87 /* combined header/blob data */ 88 struct sur40_data { 89 struct sur40_header header; 90 struct sur40_blob blobs[]; 91 } __packed; 92 93 /* read 512 bytes from endpoint 0x82 -> get header below 94 * continue reading 16k blocks until header.size bytes read */ 95 struct sur40_image_header { 96 __le32 magic; /* "SUBF" */ 97 __le32 packet_id; 98 __le32 size; /* always 0x0007e900 = 960x540 */ 99 __le32 timestamp; /* milliseconds (increases by 16 or 17 each frame) */ 100 __le32 unknown; /* "epoch?" always 02/03 00 00 00 */ 101 } __packed; 102 103 /* version information */ 104 #define DRIVER_SHORT "sur40" 105 #define DRIVER_LONG "Samsung SUR40" 106 #define DRIVER_AUTHOR "Florian 'floe' Echtler <floe@butterbrot.org>" 107 #define DRIVER_DESC "Surface2.0/SUR40/PixelSense input driver" 108 109 /* vendor and device IDs */ 110 #define ID_MICROSOFT 0x045e 111 #define ID_SUR40 0x0775 112 113 /* sensor resolution */ 114 #define SENSOR_RES_X 1920 115 #define SENSOR_RES_Y 1080 116 117 /* touch data endpoint */ 118 #define TOUCH_ENDPOINT 0x86 119 120 /* video data endpoint */ 121 #define VIDEO_ENDPOINT 0x82 122 123 /* video header fields */ 124 #define VIDEO_HEADER_MAGIC 0x46425553 125 #define VIDEO_PACKET_SIZE 16384 126 127 /* polling interval (ms) */ 128 #define POLL_INTERVAL 10 129 130 /* maximum number of contacts FIXME: this is a guess? */ 131 #define MAX_CONTACTS 64 132 133 /* control commands */ 134 #define SUR40_GET_VERSION 0xb0 /* 12 bytes string */ 135 #define SUR40_UNKNOWN1 0xb3 /* 5 bytes */ 136 #define SUR40_UNKNOWN2 0xc1 /* 24 bytes */ 137 138 #define SUR40_GET_STATE 0xc5 /* 4 bytes state (?) */ 139 #define SUR40_GET_SENSORS 0xb1 /* 8 bytes sensors */ 140 141 /* master device state */ 142 struct sur40_state { 143 144 struct usb_device *usbdev; 145 struct device *dev; 146 struct input_polled_dev *input; 147 148 struct v4l2_device v4l2; 149 struct video_device vdev; 150 struct mutex lock; 151 152 struct vb2_queue queue; 153 struct vb2_alloc_ctx *alloc_ctx; 154 struct list_head buf_list; 155 spinlock_t qlock; 156 int sequence; 157 158 struct sur40_data *bulk_in_buffer; 159 size_t bulk_in_size; 160 u8 bulk_in_epaddr; 161 162 char phys[64]; 163 }; 164 165 struct sur40_buffer { 166 struct vb2_buffer vb; 167 struct list_head list; 168 }; 169 170 /* forward declarations */ 171 static const struct video_device sur40_video_device; 172 static const struct v4l2_pix_format sur40_video_format; 173 static const struct vb2_queue sur40_queue; 174 static void sur40_process_video(struct sur40_state *sur40); 175 176 /* 177 * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT 178 * here by mistake which is very likely to have corrupted the firmware EEPROM 179 * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug. 180 * Should you ever run into a similar problem, the background story to this 181 * incident and instructions on how to fix the corrupted EEPROM are available 182 * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html 183 */ 184 185 /* command wrapper */ 186 static int sur40_command(struct sur40_state *dev, 187 u8 command, u16 index, void *buffer, u16 size) 188 { 189 return usb_control_msg(dev->usbdev, usb_rcvctrlpipe(dev->usbdev, 0), 190 command, 191 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, 192 0x00, index, buffer, size, 1000); 193 } 194 195 /* Initialization routine, called from sur40_open */ 196 static int sur40_init(struct sur40_state *dev) 197 { 198 int result; 199 u8 buffer[24]; 200 201 /* stupidly replay the original MS driver init sequence */ 202 result = sur40_command(dev, SUR40_GET_VERSION, 0x00, buffer, 12); 203 if (result < 0) 204 return result; 205 206 result = sur40_command(dev, SUR40_GET_VERSION, 0x01, buffer, 12); 207 if (result < 0) 208 return result; 209 210 result = sur40_command(dev, SUR40_GET_VERSION, 0x02, buffer, 12); 211 if (result < 0) 212 return result; 213 214 result = sur40_command(dev, SUR40_UNKNOWN2, 0x00, buffer, 24); 215 if (result < 0) 216 return result; 217 218 result = sur40_command(dev, SUR40_UNKNOWN1, 0x00, buffer, 5); 219 if (result < 0) 220 return result; 221 222 result = sur40_command(dev, SUR40_GET_VERSION, 0x03, buffer, 12); 223 224 /* 225 * Discard the result buffer - no known data inside except 226 * some version strings, maybe extract these sometime... 227 */ 228 229 return result; 230 } 231 232 /* 233 * Callback routines from input_polled_dev 234 */ 235 236 /* Enable the device, polling will now start. */ 237 static void sur40_open(struct input_polled_dev *polldev) 238 { 239 struct sur40_state *sur40 = polldev->private; 240 241 dev_dbg(sur40->dev, "open\n"); 242 sur40_init(sur40); 243 } 244 245 /* Disable device, polling has stopped. */ 246 static void sur40_close(struct input_polled_dev *polldev) 247 { 248 struct sur40_state *sur40 = polldev->private; 249 250 dev_dbg(sur40->dev, "close\n"); 251 /* 252 * There is no known way to stop the device, so we simply 253 * stop polling. 254 */ 255 } 256 257 /* 258 * This function is called when a whole contact has been processed, 259 * so that it can assign it to a slot and store the data there. 260 */ 261 static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input) 262 { 263 int wide, major, minor; 264 265 int bb_size_x = le16_to_cpu(blob->bb_size_x); 266 int bb_size_y = le16_to_cpu(blob->bb_size_y); 267 268 int pos_x = le16_to_cpu(blob->pos_x); 269 int pos_y = le16_to_cpu(blob->pos_y); 270 271 int ctr_x = le16_to_cpu(blob->ctr_x); 272 int ctr_y = le16_to_cpu(blob->ctr_y); 273 274 int slotnum = input_mt_get_slot_by_key(input, blob->blob_id); 275 if (slotnum < 0 || slotnum >= MAX_CONTACTS) 276 return; 277 278 input_mt_slot(input, slotnum); 279 input_mt_report_slot_state(input, MT_TOOL_FINGER, 1); 280 wide = (bb_size_x > bb_size_y); 281 major = max(bb_size_x, bb_size_y); 282 minor = min(bb_size_x, bb_size_y); 283 284 input_report_abs(input, ABS_MT_POSITION_X, pos_x); 285 input_report_abs(input, ABS_MT_POSITION_Y, pos_y); 286 input_report_abs(input, ABS_MT_TOOL_X, ctr_x); 287 input_report_abs(input, ABS_MT_TOOL_Y, ctr_y); 288 289 /* TODO: use a better orientation measure */ 290 input_report_abs(input, ABS_MT_ORIENTATION, wide); 291 input_report_abs(input, ABS_MT_TOUCH_MAJOR, major); 292 input_report_abs(input, ABS_MT_TOUCH_MINOR, minor); 293 } 294 295 /* core function: poll for new input data */ 296 static void sur40_poll(struct input_polled_dev *polldev) 297 { 298 struct sur40_state *sur40 = polldev->private; 299 struct input_dev *input = polldev->input; 300 int result, bulk_read, need_blobs, packet_blobs, i; 301 u32 uninitialized_var(packet_id); 302 303 struct sur40_header *header = &sur40->bulk_in_buffer->header; 304 struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0]; 305 306 dev_dbg(sur40->dev, "poll\n"); 307 308 need_blobs = -1; 309 310 do { 311 312 /* perform a blocking bulk read to get data from the device */ 313 result = usb_bulk_msg(sur40->usbdev, 314 usb_rcvbulkpipe(sur40->usbdev, sur40->bulk_in_epaddr), 315 sur40->bulk_in_buffer, sur40->bulk_in_size, 316 &bulk_read, 1000); 317 318 dev_dbg(sur40->dev, "received %d bytes\n", bulk_read); 319 320 if (result < 0) { 321 dev_err(sur40->dev, "error in usb_bulk_read\n"); 322 return; 323 } 324 325 result = bulk_read - sizeof(struct sur40_header); 326 327 if (result % sizeof(struct sur40_blob) != 0) { 328 dev_err(sur40->dev, "transfer size mismatch\n"); 329 return; 330 } 331 332 /* first packet? */ 333 if (need_blobs == -1) { 334 need_blobs = le16_to_cpu(header->count); 335 dev_dbg(sur40->dev, "need %d blobs\n", need_blobs); 336 packet_id = le32_to_cpu(header->packet_id); 337 } 338 339 /* 340 * Sanity check. when video data is also being retrieved, the 341 * packet ID will usually increase in the middle of a series 342 * instead of at the end. 343 */ 344 if (packet_id != header->packet_id) 345 dev_warn(sur40->dev, "packet ID mismatch\n"); 346 347 packet_blobs = result / sizeof(struct sur40_blob); 348 dev_dbg(sur40->dev, "received %d blobs\n", packet_blobs); 349 350 /* packets always contain at least 4 blobs, even if empty */ 351 if (packet_blobs > need_blobs) 352 packet_blobs = need_blobs; 353 354 for (i = 0; i < packet_blobs; i++) { 355 need_blobs--; 356 dev_dbg(sur40->dev, "processing blob\n"); 357 sur40_report_blob(&(inblob[i]), input); 358 } 359 360 } while (need_blobs > 0); 361 362 input_mt_sync_frame(input); 363 input_sync(input); 364 365 sur40_process_video(sur40); 366 } 367 368 /* deal with video data */ 369 static void sur40_process_video(struct sur40_state *sur40) 370 { 371 372 struct sur40_image_header *img = (void *)(sur40->bulk_in_buffer); 373 struct sur40_buffer *new_buf; 374 struct usb_sg_request sgr; 375 struct sg_table *sgt; 376 int result, bulk_read; 377 378 if (!vb2_start_streaming_called(&sur40->queue)) 379 return; 380 381 /* get a new buffer from the list */ 382 spin_lock(&sur40->qlock); 383 new_buf = list_entry(sur40->buf_list.next, struct sur40_buffer, list); 384 list_del(&new_buf->list); 385 spin_unlock(&sur40->qlock); 386 387 /* retrieve data via bulk read */ 388 result = usb_bulk_msg(sur40->usbdev, 389 usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 390 sur40->bulk_in_buffer, sur40->bulk_in_size, 391 &bulk_read, 1000); 392 393 if (result < 0) { 394 dev_err(sur40->dev, "error in usb_bulk_read\n"); 395 goto err_poll; 396 } 397 398 if (bulk_read != sizeof(struct sur40_image_header)) { 399 dev_err(sur40->dev, "received %d bytes (%zd expected)\n", 400 bulk_read, sizeof(struct sur40_image_header)); 401 goto err_poll; 402 } 403 404 if (le32_to_cpu(img->magic) != VIDEO_HEADER_MAGIC) { 405 dev_err(sur40->dev, "image magic mismatch\n"); 406 goto err_poll; 407 } 408 409 if (le32_to_cpu(img->size) != sur40_video_format.sizeimage) { 410 dev_err(sur40->dev, "image size mismatch\n"); 411 goto err_poll; 412 } 413 414 sgt = vb2_dma_sg_plane_desc(&new_buf->vb, 0); 415 416 result = usb_sg_init(&sgr, sur40->usbdev, 417 usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 0, 418 sgt->sgl, sgt->nents, sur40_video_format.sizeimage, 0); 419 if (result < 0) { 420 dev_err(sur40->dev, "error %d in usb_sg_init\n", result); 421 goto err_poll; 422 } 423 424 usb_sg_wait(&sgr); 425 if (sgr.status < 0) { 426 dev_err(sur40->dev, "error %d in usb_sg_wait\n", sgr.status); 427 goto err_poll; 428 } 429 430 /* mark as finished */ 431 v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp); 432 new_buf->vb.v4l2_buf.sequence = sur40->sequence++; 433 new_buf->vb.v4l2_buf.field = V4L2_FIELD_NONE; 434 vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_DONE); 435 return; 436 437 err_poll: 438 vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_ERROR); 439 } 440 441 /* Initialize input device parameters. */ 442 static void sur40_input_setup(struct input_dev *input_dev) 443 { 444 __set_bit(EV_KEY, input_dev->evbit); 445 __set_bit(EV_ABS, input_dev->evbit); 446 447 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 448 0, SENSOR_RES_X, 0, 0); 449 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 450 0, SENSOR_RES_Y, 0, 0); 451 452 input_set_abs_params(input_dev, ABS_MT_TOOL_X, 453 0, SENSOR_RES_X, 0, 0); 454 input_set_abs_params(input_dev, ABS_MT_TOOL_Y, 455 0, SENSOR_RES_Y, 0, 0); 456 457 /* max value unknown, but major/minor axis 458 * can never be larger than screen */ 459 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 460 0, SENSOR_RES_X, 0, 0); 461 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 462 0, SENSOR_RES_Y, 0, 0); 463 464 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0); 465 466 input_mt_init_slots(input_dev, MAX_CONTACTS, 467 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); 468 } 469 470 /* Check candidate USB interface. */ 471 static int sur40_probe(struct usb_interface *interface, 472 const struct usb_device_id *id) 473 { 474 struct usb_device *usbdev = interface_to_usbdev(interface); 475 struct sur40_state *sur40; 476 struct usb_host_interface *iface_desc; 477 struct usb_endpoint_descriptor *endpoint; 478 struct input_polled_dev *poll_dev; 479 int error; 480 481 /* Check if we really have the right interface. */ 482 iface_desc = &interface->altsetting[0]; 483 if (iface_desc->desc.bInterfaceClass != 0xFF) 484 return -ENODEV; 485 486 /* Use endpoint #4 (0x86). */ 487 endpoint = &iface_desc->endpoint[4].desc; 488 if (endpoint->bEndpointAddress != TOUCH_ENDPOINT) 489 return -ENODEV; 490 491 /* Allocate memory for our device state and initialize it. */ 492 sur40 = kzalloc(sizeof(struct sur40_state), GFP_KERNEL); 493 if (!sur40) 494 return -ENOMEM; 495 496 poll_dev = input_allocate_polled_device(); 497 if (!poll_dev) { 498 error = -ENOMEM; 499 goto err_free_dev; 500 } 501 502 /* initialize locks/lists */ 503 INIT_LIST_HEAD(&sur40->buf_list); 504 spin_lock_init(&sur40->qlock); 505 mutex_init(&sur40->lock); 506 507 /* Set up polled input device control structure */ 508 poll_dev->private = sur40; 509 poll_dev->poll_interval = POLL_INTERVAL; 510 poll_dev->open = sur40_open; 511 poll_dev->poll = sur40_poll; 512 poll_dev->close = sur40_close; 513 514 /* Set up regular input device structure */ 515 sur40_input_setup(poll_dev->input); 516 517 poll_dev->input->name = DRIVER_LONG; 518 usb_to_input_id(usbdev, &poll_dev->input->id); 519 usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys)); 520 strlcat(sur40->phys, "/input0", sizeof(sur40->phys)); 521 poll_dev->input->phys = sur40->phys; 522 poll_dev->input->dev.parent = &interface->dev; 523 524 sur40->usbdev = usbdev; 525 sur40->dev = &interface->dev; 526 sur40->input = poll_dev; 527 528 /* use the bulk-in endpoint tested above */ 529 sur40->bulk_in_size = usb_endpoint_maxp(endpoint); 530 sur40->bulk_in_epaddr = endpoint->bEndpointAddress; 531 sur40->bulk_in_buffer = kmalloc(sur40->bulk_in_size, GFP_KERNEL); 532 if (!sur40->bulk_in_buffer) { 533 dev_err(&interface->dev, "Unable to allocate input buffer."); 534 error = -ENOMEM; 535 goto err_free_polldev; 536 } 537 538 /* register the polled input device */ 539 error = input_register_polled_device(poll_dev); 540 if (error) { 541 dev_err(&interface->dev, 542 "Unable to register polled input device."); 543 goto err_free_buffer; 544 } 545 546 /* register the video master device */ 547 snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG); 548 error = v4l2_device_register(sur40->dev, &sur40->v4l2); 549 if (error) { 550 dev_err(&interface->dev, 551 "Unable to register video master device."); 552 goto err_unreg_v4l2; 553 } 554 555 /* initialize the lock and subdevice */ 556 sur40->queue = sur40_queue; 557 sur40->queue.drv_priv = sur40; 558 sur40->queue.lock = &sur40->lock; 559 560 /* initialize the queue */ 561 error = vb2_queue_init(&sur40->queue); 562 if (error) 563 goto err_unreg_v4l2; 564 565 sur40->alloc_ctx = vb2_dma_sg_init_ctx(sur40->dev); 566 if (IS_ERR(sur40->alloc_ctx)) { 567 dev_err(sur40->dev, "Can't allocate buffer context"); 568 goto err_unreg_v4l2; 569 } 570 571 sur40->vdev = sur40_video_device; 572 sur40->vdev.v4l2_dev = &sur40->v4l2; 573 sur40->vdev.lock = &sur40->lock; 574 sur40->vdev.queue = &sur40->queue; 575 video_set_drvdata(&sur40->vdev, sur40); 576 577 error = video_register_device(&sur40->vdev, VFL_TYPE_GRABBER, -1); 578 if (error) { 579 dev_err(&interface->dev, 580 "Unable to register video subdevice."); 581 goto err_unreg_video; 582 } 583 584 /* we can register the device now, as it is ready */ 585 usb_set_intfdata(interface, sur40); 586 dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC); 587 588 return 0; 589 590 err_unreg_video: 591 video_unregister_device(&sur40->vdev); 592 err_unreg_v4l2: 593 v4l2_device_unregister(&sur40->v4l2); 594 err_free_buffer: 595 kfree(sur40->bulk_in_buffer); 596 err_free_polldev: 597 input_free_polled_device(sur40->input); 598 err_free_dev: 599 kfree(sur40); 600 601 return error; 602 } 603 604 /* Unregister device & clean up. */ 605 static void sur40_disconnect(struct usb_interface *interface) 606 { 607 struct sur40_state *sur40 = usb_get_intfdata(interface); 608 609 video_unregister_device(&sur40->vdev); 610 v4l2_device_unregister(&sur40->v4l2); 611 vb2_dma_sg_cleanup_ctx(sur40->alloc_ctx); 612 613 input_unregister_polled_device(sur40->input); 614 input_free_polled_device(sur40->input); 615 kfree(sur40->bulk_in_buffer); 616 kfree(sur40); 617 618 usb_set_intfdata(interface, NULL); 619 dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC); 620 } 621 622 /* 623 * Setup the constraints of the queue: besides setting the number of planes 624 * per buffer and the size and allocation context of each plane, it also 625 * checks if sufficient buffers have been allocated. Usually 3 is a good 626 * minimum number: many DMA engines need a minimum of 2 buffers in the 627 * queue and you need to have another available for userspace processing. 628 */ 629 static int sur40_queue_setup(struct vb2_queue *q, const struct v4l2_format *fmt, 630 unsigned int *nbuffers, unsigned int *nplanes, 631 unsigned int sizes[], void *alloc_ctxs[]) 632 { 633 struct sur40_state *sur40 = vb2_get_drv_priv(q); 634 635 if (q->num_buffers + *nbuffers < 3) 636 *nbuffers = 3 - q->num_buffers; 637 638 if (fmt && fmt->fmt.pix.sizeimage < sur40_video_format.sizeimage) 639 return -EINVAL; 640 641 *nplanes = 1; 642 sizes[0] = fmt ? fmt->fmt.pix.sizeimage : sur40_video_format.sizeimage; 643 alloc_ctxs[0] = sur40->alloc_ctx; 644 645 return 0; 646 } 647 648 /* 649 * Prepare the buffer for queueing to the DMA engine: check and set the 650 * payload size. 651 */ 652 static int sur40_buffer_prepare(struct vb2_buffer *vb) 653 { 654 struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue); 655 unsigned long size = sur40_video_format.sizeimage; 656 657 if (vb2_plane_size(vb, 0) < size) { 658 dev_err(&sur40->usbdev->dev, "buffer too small (%lu < %lu)\n", 659 vb2_plane_size(vb, 0), size); 660 return -EINVAL; 661 } 662 663 vb2_set_plane_payload(vb, 0, size); 664 return 0; 665 } 666 667 /* 668 * Queue this buffer to the DMA engine. 669 */ 670 static void sur40_buffer_queue(struct vb2_buffer *vb) 671 { 672 struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue); 673 struct sur40_buffer *buf = (struct sur40_buffer *)vb; 674 675 spin_lock(&sur40->qlock); 676 list_add_tail(&buf->list, &sur40->buf_list); 677 spin_unlock(&sur40->qlock); 678 } 679 680 static void return_all_buffers(struct sur40_state *sur40, 681 enum vb2_buffer_state state) 682 { 683 struct sur40_buffer *buf, *node; 684 685 spin_lock(&sur40->qlock); 686 list_for_each_entry_safe(buf, node, &sur40->buf_list, list) { 687 vb2_buffer_done(&buf->vb, state); 688 list_del(&buf->list); 689 } 690 spin_unlock(&sur40->qlock); 691 } 692 693 /* 694 * Start streaming. First check if the minimum number of buffers have been 695 * queued. If not, then return -ENOBUFS and the vb2 framework will call 696 * this function again the next time a buffer has been queued until enough 697 * buffers are available to actually start the DMA engine. 698 */ 699 static int sur40_start_streaming(struct vb2_queue *vq, unsigned int count) 700 { 701 struct sur40_state *sur40 = vb2_get_drv_priv(vq); 702 703 sur40->sequence = 0; 704 return 0; 705 } 706 707 /* 708 * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued 709 * and passed on to the vb2 framework marked as STATE_ERROR. 710 */ 711 static void sur40_stop_streaming(struct vb2_queue *vq) 712 { 713 struct sur40_state *sur40 = vb2_get_drv_priv(vq); 714 715 /* Release all active buffers */ 716 return_all_buffers(sur40, VB2_BUF_STATE_ERROR); 717 } 718 719 /* V4L ioctl */ 720 static int sur40_vidioc_querycap(struct file *file, void *priv, 721 struct v4l2_capability *cap) 722 { 723 struct sur40_state *sur40 = video_drvdata(file); 724 725 strlcpy(cap->driver, DRIVER_SHORT, sizeof(cap->driver)); 726 strlcpy(cap->card, DRIVER_LONG, sizeof(cap->card)); 727 usb_make_path(sur40->usbdev, cap->bus_info, sizeof(cap->bus_info)); 728 cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | 729 V4L2_CAP_READWRITE | 730 V4L2_CAP_STREAMING; 731 cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS; 732 return 0; 733 } 734 735 static int sur40_vidioc_enum_input(struct file *file, void *priv, 736 struct v4l2_input *i) 737 { 738 if (i->index != 0) 739 return -EINVAL; 740 i->type = V4L2_INPUT_TYPE_CAMERA; 741 i->std = V4L2_STD_UNKNOWN; 742 strlcpy(i->name, "In-Cell Sensor", sizeof(i->name)); 743 i->capabilities = 0; 744 return 0; 745 } 746 747 static int sur40_vidioc_s_input(struct file *file, void *priv, unsigned int i) 748 { 749 return (i == 0) ? 0 : -EINVAL; 750 } 751 752 static int sur40_vidioc_g_input(struct file *file, void *priv, unsigned int *i) 753 { 754 *i = 0; 755 return 0; 756 } 757 758 static int sur40_vidioc_fmt(struct file *file, void *priv, 759 struct v4l2_format *f) 760 { 761 f->fmt.pix = sur40_video_format; 762 return 0; 763 } 764 765 static int sur40_vidioc_enum_fmt(struct file *file, void *priv, 766 struct v4l2_fmtdesc *f) 767 { 768 if (f->index != 0) 769 return -EINVAL; 770 strlcpy(f->description, "8-bit greyscale", sizeof(f->description)); 771 f->pixelformat = V4L2_PIX_FMT_GREY; 772 f->flags = 0; 773 return 0; 774 } 775 776 static const struct usb_device_id sur40_table[] = { 777 { USB_DEVICE(ID_MICROSOFT, ID_SUR40) }, /* Samsung SUR40 */ 778 { } /* terminating null entry */ 779 }; 780 MODULE_DEVICE_TABLE(usb, sur40_table); 781 782 /* V4L2 structures */ 783 static const struct vb2_ops sur40_queue_ops = { 784 .queue_setup = sur40_queue_setup, 785 .buf_prepare = sur40_buffer_prepare, 786 .buf_queue = sur40_buffer_queue, 787 .start_streaming = sur40_start_streaming, 788 .stop_streaming = sur40_stop_streaming, 789 .wait_prepare = vb2_ops_wait_prepare, 790 .wait_finish = vb2_ops_wait_finish, 791 }; 792 793 static const struct vb2_queue sur40_queue = { 794 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, 795 /* 796 * VB2_USERPTR in currently not enabled: passing a user pointer to 797 * dma-sg will result in segment sizes that are not a multiple of 798 * 512 bytes, which is required by the host controller. 799 */ 800 .io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF, 801 .buf_struct_size = sizeof(struct sur40_buffer), 802 .ops = &sur40_queue_ops, 803 .mem_ops = &vb2_dma_sg_memops, 804 .timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC, 805 .min_buffers_needed = 3, 806 }; 807 808 static const struct v4l2_file_operations sur40_video_fops = { 809 .owner = THIS_MODULE, 810 .open = v4l2_fh_open, 811 .release = vb2_fop_release, 812 .unlocked_ioctl = video_ioctl2, 813 .read = vb2_fop_read, 814 .mmap = vb2_fop_mmap, 815 .poll = vb2_fop_poll, 816 }; 817 818 static const struct v4l2_ioctl_ops sur40_video_ioctl_ops = { 819 820 .vidioc_querycap = sur40_vidioc_querycap, 821 822 .vidioc_enum_fmt_vid_cap = sur40_vidioc_enum_fmt, 823 .vidioc_try_fmt_vid_cap = sur40_vidioc_fmt, 824 .vidioc_s_fmt_vid_cap = sur40_vidioc_fmt, 825 .vidioc_g_fmt_vid_cap = sur40_vidioc_fmt, 826 827 .vidioc_enum_input = sur40_vidioc_enum_input, 828 .vidioc_g_input = sur40_vidioc_g_input, 829 .vidioc_s_input = sur40_vidioc_s_input, 830 831 .vidioc_reqbufs = vb2_ioctl_reqbufs, 832 .vidioc_create_bufs = vb2_ioctl_create_bufs, 833 .vidioc_querybuf = vb2_ioctl_querybuf, 834 .vidioc_qbuf = vb2_ioctl_qbuf, 835 .vidioc_dqbuf = vb2_ioctl_dqbuf, 836 .vidioc_expbuf = vb2_ioctl_expbuf, 837 838 .vidioc_streamon = vb2_ioctl_streamon, 839 .vidioc_streamoff = vb2_ioctl_streamoff, 840 }; 841 842 static const struct video_device sur40_video_device = { 843 .name = DRIVER_LONG, 844 .fops = &sur40_video_fops, 845 .ioctl_ops = &sur40_video_ioctl_ops, 846 .release = video_device_release_empty, 847 }; 848 849 static const struct v4l2_pix_format sur40_video_format = { 850 .pixelformat = V4L2_PIX_FMT_GREY, 851 .width = SENSOR_RES_X / 2, 852 .height = SENSOR_RES_Y / 2, 853 .field = V4L2_FIELD_NONE, 854 .colorspace = V4L2_COLORSPACE_SRGB, 855 .bytesperline = SENSOR_RES_X / 2, 856 .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2), 857 }; 858 859 /* USB-specific object needed to register this driver with the USB subsystem. */ 860 static struct usb_driver sur40_driver = { 861 .name = DRIVER_SHORT, 862 .probe = sur40_probe, 863 .disconnect = sur40_disconnect, 864 .id_table = sur40_table, 865 }; 866 867 module_usb_driver(sur40_driver); 868 869 MODULE_AUTHOR(DRIVER_AUTHOR); 870 MODULE_DESCRIPTION(DRIVER_DESC); 871 MODULE_LICENSE("GPL"); 872