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-v4l2.h> 42 #include <media/videobuf2-dma-sg.h> 43 44 /* read 512 bytes from endpoint 0x86 -> get header + blobs */ 45 struct sur40_header { 46 47 __le16 type; /* always 0x0001 */ 48 __le16 count; /* count of blobs (if 0: continue prev. packet) */ 49 50 __le32 packet_id; /* unique ID for all packets in one frame */ 51 52 __le32 timestamp; /* milliseconds (inc. by 16 or 17 each frame) */ 53 __le32 unknown; /* "epoch?" always 02/03 00 00 00 */ 54 55 } __packed; 56 57 struct sur40_blob { 58 59 __le16 blob_id; 60 61 u8 action; /* 0x02 = enter/exit, 0x03 = update (?) */ 62 u8 unknown; /* always 0x01 or 0x02 (no idea what this is?) */ 63 64 __le16 bb_pos_x; /* upper left corner of bounding box */ 65 __le16 bb_pos_y; 66 67 __le16 bb_size_x; /* size of bounding box */ 68 __le16 bb_size_y; 69 70 __le16 pos_x; /* finger tip position */ 71 __le16 pos_y; 72 73 __le16 ctr_x; /* centroid position */ 74 __le16 ctr_y; 75 76 __le16 axis_x; /* somehow related to major/minor axis, mostly: */ 77 __le16 axis_y; /* axis_x == bb_size_y && axis_y == bb_size_x */ 78 79 __le32 angle; /* orientation in radians relative to x axis - 80 actually an IEEE754 float, don't use in kernel */ 81 82 __le32 area; /* size in pixels/pressure (?) */ 83 84 u8 padding[32]; 85 86 } __packed; 87 88 /* combined header/blob data */ 89 struct sur40_data { 90 struct sur40_header header; 91 struct sur40_blob blobs[]; 92 } __packed; 93 94 /* read 512 bytes from endpoint 0x82 -> get header below 95 * continue reading 16k blocks until header.size bytes read */ 96 struct sur40_image_header { 97 __le32 magic; /* "SUBF" */ 98 __le32 packet_id; 99 __le32 size; /* always 0x0007e900 = 960x540 */ 100 __le32 timestamp; /* milliseconds (increases by 16 or 17 each frame) */ 101 __le32 unknown; /* "epoch?" always 02/03 00 00 00 */ 102 } __packed; 103 104 /* version information */ 105 #define DRIVER_SHORT "sur40" 106 #define DRIVER_LONG "Samsung SUR40" 107 #define DRIVER_AUTHOR "Florian 'floe' Echtler <floe@butterbrot.org>" 108 #define DRIVER_DESC "Surface2.0/SUR40/PixelSense input driver" 109 110 /* vendor and device IDs */ 111 #define ID_MICROSOFT 0x045e 112 #define ID_SUR40 0x0775 113 114 /* sensor resolution */ 115 #define SENSOR_RES_X 1920 116 #define SENSOR_RES_Y 1080 117 118 /* touch data endpoint */ 119 #define TOUCH_ENDPOINT 0x86 120 121 /* video data endpoint */ 122 #define VIDEO_ENDPOINT 0x82 123 124 /* video header fields */ 125 #define VIDEO_HEADER_MAGIC 0x46425553 126 #define VIDEO_PACKET_SIZE 16384 127 128 /* polling interval (ms) */ 129 #define POLL_INTERVAL 4 130 131 /* maximum number of contacts FIXME: this is a guess? */ 132 #define MAX_CONTACTS 64 133 134 /* control commands */ 135 #define SUR40_GET_VERSION 0xb0 /* 12 bytes string */ 136 #define SUR40_UNKNOWN1 0xb3 /* 5 bytes */ 137 #define SUR40_UNKNOWN2 0xc1 /* 24 bytes */ 138 139 #define SUR40_GET_STATE 0xc5 /* 4 bytes state (?) */ 140 #define SUR40_GET_SENSORS 0xb1 /* 8 bytes sensors */ 141 142 /* master device state */ 143 struct sur40_state { 144 145 struct usb_device *usbdev; 146 struct device *dev; 147 struct input_polled_dev *input; 148 149 struct v4l2_device v4l2; 150 struct video_device vdev; 151 struct mutex lock; 152 153 struct vb2_queue queue; 154 struct vb2_alloc_ctx *alloc_ctx; 155 struct list_head buf_list; 156 spinlock_t qlock; 157 int sequence; 158 159 struct sur40_data *bulk_in_buffer; 160 size_t bulk_in_size; 161 u8 bulk_in_epaddr; 162 163 char phys[64]; 164 }; 165 166 struct sur40_buffer { 167 struct vb2_v4l2_buffer vb; 168 struct list_head list; 169 }; 170 171 /* forward declarations */ 172 static const struct video_device sur40_video_device; 173 static const struct v4l2_pix_format sur40_video_format; 174 static const struct vb2_queue sur40_queue; 175 static void sur40_process_video(struct sur40_state *sur40); 176 177 /* 178 * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT 179 * here by mistake which is very likely to have corrupted the firmware EEPROM 180 * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug. 181 * Should you ever run into a similar problem, the background story to this 182 * incident and instructions on how to fix the corrupted EEPROM are available 183 * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html 184 */ 185 186 /* command wrapper */ 187 static int sur40_command(struct sur40_state *dev, 188 u8 command, u16 index, void *buffer, u16 size) 189 { 190 return usb_control_msg(dev->usbdev, usb_rcvctrlpipe(dev->usbdev, 0), 191 command, 192 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, 193 0x00, index, buffer, size, 1000); 194 } 195 196 /* Initialization routine, called from sur40_open */ 197 static int sur40_init(struct sur40_state *dev) 198 { 199 int result; 200 u8 *buffer; 201 202 buffer = kmalloc(24, GFP_KERNEL); 203 if (!buffer) { 204 result = -ENOMEM; 205 goto error; 206 } 207 208 /* stupidly replay the original MS driver init sequence */ 209 result = sur40_command(dev, SUR40_GET_VERSION, 0x00, buffer, 12); 210 if (result < 0) 211 goto error; 212 213 result = sur40_command(dev, SUR40_GET_VERSION, 0x01, buffer, 12); 214 if (result < 0) 215 goto error; 216 217 result = sur40_command(dev, SUR40_GET_VERSION, 0x02, buffer, 12); 218 if (result < 0) 219 goto error; 220 221 result = sur40_command(dev, SUR40_UNKNOWN2, 0x00, buffer, 24); 222 if (result < 0) 223 goto error; 224 225 result = sur40_command(dev, SUR40_UNKNOWN1, 0x00, buffer, 5); 226 if (result < 0) 227 goto error; 228 229 result = sur40_command(dev, SUR40_GET_VERSION, 0x03, buffer, 12); 230 231 /* 232 * Discard the result buffer - no known data inside except 233 * some version strings, maybe extract these sometime... 234 */ 235 error: 236 kfree(buffer); 237 return result; 238 } 239 240 /* 241 * Callback routines from input_polled_dev 242 */ 243 244 /* Enable the device, polling will now start. */ 245 static void sur40_open(struct input_polled_dev *polldev) 246 { 247 struct sur40_state *sur40 = polldev->private; 248 249 dev_dbg(sur40->dev, "open\n"); 250 sur40_init(sur40); 251 } 252 253 /* Disable device, polling has stopped. */ 254 static void sur40_close(struct input_polled_dev *polldev) 255 { 256 struct sur40_state *sur40 = polldev->private; 257 258 dev_dbg(sur40->dev, "close\n"); 259 /* 260 * There is no known way to stop the device, so we simply 261 * stop polling. 262 */ 263 } 264 265 /* 266 * This function is called when a whole contact has been processed, 267 * so that it can assign it to a slot and store the data there. 268 */ 269 static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input) 270 { 271 int wide, major, minor; 272 273 int bb_size_x = le16_to_cpu(blob->bb_size_x); 274 int bb_size_y = le16_to_cpu(blob->bb_size_y); 275 276 int pos_x = le16_to_cpu(blob->pos_x); 277 int pos_y = le16_to_cpu(blob->pos_y); 278 279 int ctr_x = le16_to_cpu(blob->ctr_x); 280 int ctr_y = le16_to_cpu(blob->ctr_y); 281 282 int slotnum = input_mt_get_slot_by_key(input, blob->blob_id); 283 if (slotnum < 0 || slotnum >= MAX_CONTACTS) 284 return; 285 286 input_mt_slot(input, slotnum); 287 input_mt_report_slot_state(input, MT_TOOL_FINGER, 1); 288 wide = (bb_size_x > bb_size_y); 289 major = max(bb_size_x, bb_size_y); 290 minor = min(bb_size_x, bb_size_y); 291 292 input_report_abs(input, ABS_MT_POSITION_X, pos_x); 293 input_report_abs(input, ABS_MT_POSITION_Y, pos_y); 294 input_report_abs(input, ABS_MT_TOOL_X, ctr_x); 295 input_report_abs(input, ABS_MT_TOOL_Y, ctr_y); 296 297 /* TODO: use a better orientation measure */ 298 input_report_abs(input, ABS_MT_ORIENTATION, wide); 299 input_report_abs(input, ABS_MT_TOUCH_MAJOR, major); 300 input_report_abs(input, ABS_MT_TOUCH_MINOR, minor); 301 } 302 303 /* core function: poll for new input data */ 304 static void sur40_poll(struct input_polled_dev *polldev) 305 { 306 struct sur40_state *sur40 = polldev->private; 307 struct input_dev *input = polldev->input; 308 int result, bulk_read, need_blobs, packet_blobs, i; 309 u32 uninitialized_var(packet_id); 310 311 struct sur40_header *header = &sur40->bulk_in_buffer->header; 312 struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0]; 313 314 dev_dbg(sur40->dev, "poll\n"); 315 316 need_blobs = -1; 317 318 do { 319 320 /* perform a blocking bulk read to get data from the device */ 321 result = usb_bulk_msg(sur40->usbdev, 322 usb_rcvbulkpipe(sur40->usbdev, sur40->bulk_in_epaddr), 323 sur40->bulk_in_buffer, sur40->bulk_in_size, 324 &bulk_read, 1000); 325 326 dev_dbg(sur40->dev, "received %d bytes\n", bulk_read); 327 328 if (result < 0) { 329 dev_err(sur40->dev, "error in usb_bulk_read\n"); 330 return; 331 } 332 333 result = bulk_read - sizeof(struct sur40_header); 334 335 if (result % sizeof(struct sur40_blob) != 0) { 336 dev_err(sur40->dev, "transfer size mismatch\n"); 337 return; 338 } 339 340 /* first packet? */ 341 if (need_blobs == -1) { 342 need_blobs = le16_to_cpu(header->count); 343 dev_dbg(sur40->dev, "need %d blobs\n", need_blobs); 344 packet_id = le32_to_cpu(header->packet_id); 345 } 346 347 /* 348 * Sanity check. when video data is also being retrieved, the 349 * packet ID will usually increase in the middle of a series 350 * instead of at the end. 351 */ 352 if (packet_id != header->packet_id) 353 dev_dbg(sur40->dev, "packet ID mismatch\n"); 354 355 packet_blobs = result / sizeof(struct sur40_blob); 356 dev_dbg(sur40->dev, "received %d blobs\n", packet_blobs); 357 358 /* packets always contain at least 4 blobs, even if empty */ 359 if (packet_blobs > need_blobs) 360 packet_blobs = need_blobs; 361 362 for (i = 0; i < packet_blobs; i++) { 363 need_blobs--; 364 dev_dbg(sur40->dev, "processing blob\n"); 365 sur40_report_blob(&(inblob[i]), input); 366 } 367 368 } while (need_blobs > 0); 369 370 input_mt_sync_frame(input); 371 input_sync(input); 372 373 sur40_process_video(sur40); 374 } 375 376 /* deal with video data */ 377 static void sur40_process_video(struct sur40_state *sur40) 378 { 379 380 struct sur40_image_header *img = (void *)(sur40->bulk_in_buffer); 381 struct sur40_buffer *new_buf; 382 struct usb_sg_request sgr; 383 struct sg_table *sgt; 384 int result, bulk_read; 385 386 if (!vb2_start_streaming_called(&sur40->queue)) 387 return; 388 389 /* get a new buffer from the list */ 390 spin_lock(&sur40->qlock); 391 if (list_empty(&sur40->buf_list)) { 392 dev_dbg(sur40->dev, "buffer queue empty\n"); 393 spin_unlock(&sur40->qlock); 394 return; 395 } 396 new_buf = list_entry(sur40->buf_list.next, struct sur40_buffer, list); 397 list_del(&new_buf->list); 398 spin_unlock(&sur40->qlock); 399 400 dev_dbg(sur40->dev, "buffer acquired\n"); 401 402 /* retrieve data via bulk read */ 403 result = usb_bulk_msg(sur40->usbdev, 404 usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 405 sur40->bulk_in_buffer, sur40->bulk_in_size, 406 &bulk_read, 1000); 407 408 if (result < 0) { 409 dev_err(sur40->dev, "error in usb_bulk_read\n"); 410 goto err_poll; 411 } 412 413 if (bulk_read != sizeof(struct sur40_image_header)) { 414 dev_err(sur40->dev, "received %d bytes (%zd expected)\n", 415 bulk_read, sizeof(struct sur40_image_header)); 416 goto err_poll; 417 } 418 419 if (le32_to_cpu(img->magic) != VIDEO_HEADER_MAGIC) { 420 dev_err(sur40->dev, "image magic mismatch\n"); 421 goto err_poll; 422 } 423 424 if (le32_to_cpu(img->size) != sur40_video_format.sizeimage) { 425 dev_err(sur40->dev, "image size mismatch\n"); 426 goto err_poll; 427 } 428 429 dev_dbg(sur40->dev, "header acquired\n"); 430 431 sgt = vb2_dma_sg_plane_desc(&new_buf->vb.vb2_buf, 0); 432 433 result = usb_sg_init(&sgr, sur40->usbdev, 434 usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 0, 435 sgt->sgl, sgt->nents, sur40_video_format.sizeimage, 0); 436 if (result < 0) { 437 dev_err(sur40->dev, "error %d in usb_sg_init\n", result); 438 goto err_poll; 439 } 440 441 usb_sg_wait(&sgr); 442 if (sgr.status < 0) { 443 dev_err(sur40->dev, "error %d in usb_sg_wait\n", sgr.status); 444 goto err_poll; 445 } 446 447 dev_dbg(sur40->dev, "image acquired\n"); 448 449 /* return error if streaming was stopped in the meantime */ 450 if (sur40->sequence == -1) 451 goto err_poll; 452 453 /* mark as finished */ 454 new_buf->vb.vb2_buf.timestamp = ktime_get_ns(); 455 new_buf->vb.sequence = sur40->sequence++; 456 new_buf->vb.field = V4L2_FIELD_NONE; 457 vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_DONE); 458 dev_dbg(sur40->dev, "buffer marked done\n"); 459 return; 460 461 err_poll: 462 vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_ERROR); 463 } 464 465 /* Initialize input device parameters. */ 466 static void sur40_input_setup(struct input_dev *input_dev) 467 { 468 __set_bit(EV_KEY, input_dev->evbit); 469 __set_bit(EV_ABS, input_dev->evbit); 470 471 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 472 0, SENSOR_RES_X, 0, 0); 473 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 474 0, SENSOR_RES_Y, 0, 0); 475 476 input_set_abs_params(input_dev, ABS_MT_TOOL_X, 477 0, SENSOR_RES_X, 0, 0); 478 input_set_abs_params(input_dev, ABS_MT_TOOL_Y, 479 0, SENSOR_RES_Y, 0, 0); 480 481 /* max value unknown, but major/minor axis 482 * can never be larger than screen */ 483 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 484 0, SENSOR_RES_X, 0, 0); 485 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 486 0, SENSOR_RES_Y, 0, 0); 487 488 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0); 489 490 input_mt_init_slots(input_dev, MAX_CONTACTS, 491 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); 492 } 493 494 /* Check candidate USB interface. */ 495 static int sur40_probe(struct usb_interface *interface, 496 const struct usb_device_id *id) 497 { 498 struct usb_device *usbdev = interface_to_usbdev(interface); 499 struct sur40_state *sur40; 500 struct usb_host_interface *iface_desc; 501 struct usb_endpoint_descriptor *endpoint; 502 struct input_polled_dev *poll_dev; 503 int error; 504 505 /* Check if we really have the right interface. */ 506 iface_desc = &interface->altsetting[0]; 507 if (iface_desc->desc.bInterfaceClass != 0xFF) 508 return -ENODEV; 509 510 /* Use endpoint #4 (0x86). */ 511 endpoint = &iface_desc->endpoint[4].desc; 512 if (endpoint->bEndpointAddress != TOUCH_ENDPOINT) 513 return -ENODEV; 514 515 /* Allocate memory for our device state and initialize it. */ 516 sur40 = kzalloc(sizeof(struct sur40_state), GFP_KERNEL); 517 if (!sur40) 518 return -ENOMEM; 519 520 poll_dev = input_allocate_polled_device(); 521 if (!poll_dev) { 522 error = -ENOMEM; 523 goto err_free_dev; 524 } 525 526 /* initialize locks/lists */ 527 INIT_LIST_HEAD(&sur40->buf_list); 528 spin_lock_init(&sur40->qlock); 529 mutex_init(&sur40->lock); 530 531 /* Set up polled input device control structure */ 532 poll_dev->private = sur40; 533 poll_dev->poll_interval = POLL_INTERVAL; 534 poll_dev->open = sur40_open; 535 poll_dev->poll = sur40_poll; 536 poll_dev->close = sur40_close; 537 538 /* Set up regular input device structure */ 539 sur40_input_setup(poll_dev->input); 540 541 poll_dev->input->name = DRIVER_LONG; 542 usb_to_input_id(usbdev, &poll_dev->input->id); 543 usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys)); 544 strlcat(sur40->phys, "/input0", sizeof(sur40->phys)); 545 poll_dev->input->phys = sur40->phys; 546 poll_dev->input->dev.parent = &interface->dev; 547 548 sur40->usbdev = usbdev; 549 sur40->dev = &interface->dev; 550 sur40->input = poll_dev; 551 552 /* use the bulk-in endpoint tested above */ 553 sur40->bulk_in_size = usb_endpoint_maxp(endpoint); 554 sur40->bulk_in_epaddr = endpoint->bEndpointAddress; 555 sur40->bulk_in_buffer = kmalloc(sur40->bulk_in_size, GFP_KERNEL); 556 if (!sur40->bulk_in_buffer) { 557 dev_err(&interface->dev, "Unable to allocate input buffer."); 558 error = -ENOMEM; 559 goto err_free_polldev; 560 } 561 562 /* register the polled input device */ 563 error = input_register_polled_device(poll_dev); 564 if (error) { 565 dev_err(&interface->dev, 566 "Unable to register polled input device."); 567 goto err_free_buffer; 568 } 569 570 /* register the video master device */ 571 snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG); 572 error = v4l2_device_register(sur40->dev, &sur40->v4l2); 573 if (error) { 574 dev_err(&interface->dev, 575 "Unable to register video master device."); 576 goto err_unreg_v4l2; 577 } 578 579 /* initialize the lock and subdevice */ 580 sur40->queue = sur40_queue; 581 sur40->queue.drv_priv = sur40; 582 sur40->queue.lock = &sur40->lock; 583 584 /* initialize the queue */ 585 error = vb2_queue_init(&sur40->queue); 586 if (error) 587 goto err_unreg_v4l2; 588 589 sur40->alloc_ctx = vb2_dma_sg_init_ctx(sur40->dev); 590 if (IS_ERR(sur40->alloc_ctx)) { 591 dev_err(sur40->dev, "Can't allocate buffer context"); 592 error = PTR_ERR(sur40->alloc_ctx); 593 goto err_unreg_v4l2; 594 } 595 596 sur40->vdev = sur40_video_device; 597 sur40->vdev.v4l2_dev = &sur40->v4l2; 598 sur40->vdev.lock = &sur40->lock; 599 sur40->vdev.queue = &sur40->queue; 600 video_set_drvdata(&sur40->vdev, sur40); 601 602 error = video_register_device(&sur40->vdev, VFL_TYPE_GRABBER, -1); 603 if (error) { 604 dev_err(&interface->dev, 605 "Unable to register video subdevice."); 606 goto err_unreg_video; 607 } 608 609 /* we can register the device now, as it is ready */ 610 usb_set_intfdata(interface, sur40); 611 dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC); 612 613 return 0; 614 615 err_unreg_video: 616 video_unregister_device(&sur40->vdev); 617 err_unreg_v4l2: 618 v4l2_device_unregister(&sur40->v4l2); 619 err_free_buffer: 620 kfree(sur40->bulk_in_buffer); 621 err_free_polldev: 622 input_free_polled_device(sur40->input); 623 err_free_dev: 624 kfree(sur40); 625 626 return error; 627 } 628 629 /* Unregister device & clean up. */ 630 static void sur40_disconnect(struct usb_interface *interface) 631 { 632 struct sur40_state *sur40 = usb_get_intfdata(interface); 633 634 video_unregister_device(&sur40->vdev); 635 v4l2_device_unregister(&sur40->v4l2); 636 vb2_dma_sg_cleanup_ctx(sur40->alloc_ctx); 637 638 input_unregister_polled_device(sur40->input); 639 input_free_polled_device(sur40->input); 640 kfree(sur40->bulk_in_buffer); 641 kfree(sur40); 642 643 usb_set_intfdata(interface, NULL); 644 dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC); 645 } 646 647 /* 648 * Setup the constraints of the queue: besides setting the number of planes 649 * per buffer and the size and allocation context of each plane, it also 650 * checks if sufficient buffers have been allocated. Usually 3 is a good 651 * minimum number: many DMA engines need a minimum of 2 buffers in the 652 * queue and you need to have another available for userspace processing. 653 */ 654 static int sur40_queue_setup(struct vb2_queue *q, 655 unsigned int *nbuffers, unsigned int *nplanes, 656 unsigned int sizes[], void *alloc_ctxs[]) 657 { 658 struct sur40_state *sur40 = vb2_get_drv_priv(q); 659 660 if (q->num_buffers + *nbuffers < 3) 661 *nbuffers = 3 - q->num_buffers; 662 alloc_ctxs[0] = sur40->alloc_ctx; 663 664 if (*nplanes) 665 return sizes[0] < sur40_video_format.sizeimage ? -EINVAL : 0; 666 667 *nplanes = 1; 668 sizes[0] = sur40_video_format.sizeimage; 669 670 return 0; 671 } 672 673 /* 674 * Prepare the buffer for queueing to the DMA engine: check and set the 675 * payload size. 676 */ 677 static int sur40_buffer_prepare(struct vb2_buffer *vb) 678 { 679 struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue); 680 unsigned long size = sur40_video_format.sizeimage; 681 682 if (vb2_plane_size(vb, 0) < size) { 683 dev_err(&sur40->usbdev->dev, "buffer too small (%lu < %lu)\n", 684 vb2_plane_size(vb, 0), size); 685 return -EINVAL; 686 } 687 688 vb2_set_plane_payload(vb, 0, size); 689 return 0; 690 } 691 692 /* 693 * Queue this buffer to the DMA engine. 694 */ 695 static void sur40_buffer_queue(struct vb2_buffer *vb) 696 { 697 struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue); 698 struct sur40_buffer *buf = (struct sur40_buffer *)vb; 699 700 spin_lock(&sur40->qlock); 701 list_add_tail(&buf->list, &sur40->buf_list); 702 spin_unlock(&sur40->qlock); 703 } 704 705 static void return_all_buffers(struct sur40_state *sur40, 706 enum vb2_buffer_state state) 707 { 708 struct sur40_buffer *buf, *node; 709 710 spin_lock(&sur40->qlock); 711 list_for_each_entry_safe(buf, node, &sur40->buf_list, list) { 712 vb2_buffer_done(&buf->vb.vb2_buf, state); 713 list_del(&buf->list); 714 } 715 spin_unlock(&sur40->qlock); 716 } 717 718 /* 719 * Start streaming. First check if the minimum number of buffers have been 720 * queued. If not, then return -ENOBUFS and the vb2 framework will call 721 * this function again the next time a buffer has been queued until enough 722 * buffers are available to actually start the DMA engine. 723 */ 724 static int sur40_start_streaming(struct vb2_queue *vq, unsigned int count) 725 { 726 struct sur40_state *sur40 = vb2_get_drv_priv(vq); 727 728 sur40->sequence = 0; 729 return 0; 730 } 731 732 /* 733 * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued 734 * and passed on to the vb2 framework marked as STATE_ERROR. 735 */ 736 static void sur40_stop_streaming(struct vb2_queue *vq) 737 { 738 struct sur40_state *sur40 = vb2_get_drv_priv(vq); 739 sur40->sequence = -1; 740 741 /* Release all active buffers */ 742 return_all_buffers(sur40, VB2_BUF_STATE_ERROR); 743 } 744 745 /* V4L ioctl */ 746 static int sur40_vidioc_querycap(struct file *file, void *priv, 747 struct v4l2_capability *cap) 748 { 749 struct sur40_state *sur40 = video_drvdata(file); 750 751 strlcpy(cap->driver, DRIVER_SHORT, sizeof(cap->driver)); 752 strlcpy(cap->card, DRIVER_LONG, sizeof(cap->card)); 753 usb_make_path(sur40->usbdev, cap->bus_info, sizeof(cap->bus_info)); 754 cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | 755 V4L2_CAP_READWRITE | 756 V4L2_CAP_STREAMING; 757 cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS; 758 return 0; 759 } 760 761 static int sur40_vidioc_enum_input(struct file *file, void *priv, 762 struct v4l2_input *i) 763 { 764 if (i->index != 0) 765 return -EINVAL; 766 i->type = V4L2_INPUT_TYPE_CAMERA; 767 i->std = V4L2_STD_UNKNOWN; 768 strlcpy(i->name, "In-Cell Sensor", sizeof(i->name)); 769 i->capabilities = 0; 770 return 0; 771 } 772 773 static int sur40_vidioc_s_input(struct file *file, void *priv, unsigned int i) 774 { 775 return (i == 0) ? 0 : -EINVAL; 776 } 777 778 static int sur40_vidioc_g_input(struct file *file, void *priv, unsigned int *i) 779 { 780 *i = 0; 781 return 0; 782 } 783 784 static int sur40_vidioc_fmt(struct file *file, void *priv, 785 struct v4l2_format *f) 786 { 787 f->fmt.pix = sur40_video_format; 788 return 0; 789 } 790 791 static int sur40_vidioc_enum_fmt(struct file *file, void *priv, 792 struct v4l2_fmtdesc *f) 793 { 794 if (f->index != 0) 795 return -EINVAL; 796 strlcpy(f->description, "8-bit greyscale", sizeof(f->description)); 797 f->pixelformat = V4L2_PIX_FMT_GREY; 798 f->flags = 0; 799 return 0; 800 } 801 802 static int sur40_vidioc_enum_framesizes(struct file *file, void *priv, 803 struct v4l2_frmsizeenum *f) 804 { 805 if ((f->index != 0) || (f->pixel_format != V4L2_PIX_FMT_GREY)) 806 return -EINVAL; 807 808 f->type = V4L2_FRMSIZE_TYPE_DISCRETE; 809 f->discrete.width = sur40_video_format.width; 810 f->discrete.height = sur40_video_format.height; 811 return 0; 812 } 813 814 static int sur40_vidioc_enum_frameintervals(struct file *file, void *priv, 815 struct v4l2_frmivalenum *f) 816 { 817 if ((f->index > 1) || (f->pixel_format != V4L2_PIX_FMT_GREY) 818 || (f->width != sur40_video_format.width) 819 || (f->height != sur40_video_format.height)) 820 return -EINVAL; 821 822 f->type = V4L2_FRMIVAL_TYPE_DISCRETE; 823 f->discrete.denominator = 60/(f->index+1); 824 f->discrete.numerator = 1; 825 return 0; 826 } 827 828 829 static const struct usb_device_id sur40_table[] = { 830 { USB_DEVICE(ID_MICROSOFT, ID_SUR40) }, /* Samsung SUR40 */ 831 { } /* terminating null entry */ 832 }; 833 MODULE_DEVICE_TABLE(usb, sur40_table); 834 835 /* V4L2 structures */ 836 static const struct vb2_ops sur40_queue_ops = { 837 .queue_setup = sur40_queue_setup, 838 .buf_prepare = sur40_buffer_prepare, 839 .buf_queue = sur40_buffer_queue, 840 .start_streaming = sur40_start_streaming, 841 .stop_streaming = sur40_stop_streaming, 842 .wait_prepare = vb2_ops_wait_prepare, 843 .wait_finish = vb2_ops_wait_finish, 844 }; 845 846 static const struct vb2_queue sur40_queue = { 847 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, 848 /* 849 * VB2_USERPTR in currently not enabled: passing a user pointer to 850 * dma-sg will result in segment sizes that are not a multiple of 851 * 512 bytes, which is required by the host controller. 852 */ 853 .io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF, 854 .buf_struct_size = sizeof(struct sur40_buffer), 855 .ops = &sur40_queue_ops, 856 .mem_ops = &vb2_dma_sg_memops, 857 .timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC, 858 .min_buffers_needed = 3, 859 }; 860 861 static const struct v4l2_file_operations sur40_video_fops = { 862 .owner = THIS_MODULE, 863 .open = v4l2_fh_open, 864 .release = vb2_fop_release, 865 .unlocked_ioctl = video_ioctl2, 866 .read = vb2_fop_read, 867 .mmap = vb2_fop_mmap, 868 .poll = vb2_fop_poll, 869 }; 870 871 static const struct v4l2_ioctl_ops sur40_video_ioctl_ops = { 872 873 .vidioc_querycap = sur40_vidioc_querycap, 874 875 .vidioc_enum_fmt_vid_cap = sur40_vidioc_enum_fmt, 876 .vidioc_try_fmt_vid_cap = sur40_vidioc_fmt, 877 .vidioc_s_fmt_vid_cap = sur40_vidioc_fmt, 878 .vidioc_g_fmt_vid_cap = sur40_vidioc_fmt, 879 880 .vidioc_enum_framesizes = sur40_vidioc_enum_framesizes, 881 .vidioc_enum_frameintervals = sur40_vidioc_enum_frameintervals, 882 883 .vidioc_enum_input = sur40_vidioc_enum_input, 884 .vidioc_g_input = sur40_vidioc_g_input, 885 .vidioc_s_input = sur40_vidioc_s_input, 886 887 .vidioc_reqbufs = vb2_ioctl_reqbufs, 888 .vidioc_create_bufs = vb2_ioctl_create_bufs, 889 .vidioc_querybuf = vb2_ioctl_querybuf, 890 .vidioc_qbuf = vb2_ioctl_qbuf, 891 .vidioc_dqbuf = vb2_ioctl_dqbuf, 892 .vidioc_expbuf = vb2_ioctl_expbuf, 893 894 .vidioc_streamon = vb2_ioctl_streamon, 895 .vidioc_streamoff = vb2_ioctl_streamoff, 896 }; 897 898 static const struct video_device sur40_video_device = { 899 .name = DRIVER_LONG, 900 .fops = &sur40_video_fops, 901 .ioctl_ops = &sur40_video_ioctl_ops, 902 .release = video_device_release_empty, 903 }; 904 905 static const struct v4l2_pix_format sur40_video_format = { 906 .pixelformat = V4L2_PIX_FMT_GREY, 907 .width = SENSOR_RES_X / 2, 908 .height = SENSOR_RES_Y / 2, 909 .field = V4L2_FIELD_NONE, 910 .colorspace = V4L2_COLORSPACE_SRGB, 911 .bytesperline = SENSOR_RES_X / 2, 912 .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2), 913 }; 914 915 /* USB-specific object needed to register this driver with the USB subsystem. */ 916 static struct usb_driver sur40_driver = { 917 .name = DRIVER_SHORT, 918 .probe = sur40_probe, 919 .disconnect = sur40_disconnect, 920 .id_table = sur40_table, 921 }; 922 923 module_usb_driver(sur40_driver); 924 925 MODULE_AUTHOR(DRIVER_AUTHOR); 926 MODULE_DESCRIPTION(DRIVER_DESC); 927 MODULE_LICENSE("GPL"); 928