drivers/input/touchscreen/sur40.c

   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 1
 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 static const struct v4l2_pix_format sur40_pix_format[] = {
 143         {
 144                 .pixelformat = V4L2_TCH_FMT_TU08,
 145                 .width  = SENSOR_RES_X / 2,
 146                 .height = SENSOR_RES_Y / 2,
 147                 .field = V4L2_FIELD_NONE,
 148                 .colorspace = V4L2_COLORSPACE_SRGB,
 149                 .bytesperline = SENSOR_RES_X / 2,
 150                 .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2),
 151         },
 152         {
 153                 .pixelformat = V4L2_PIX_FMT_GREY,
 154                 .width  = SENSOR_RES_X / 2,
 155                 .height = SENSOR_RES_Y / 2,
 156                 .field = V4L2_FIELD_NONE,
 157                 .colorspace = V4L2_COLORSPACE_SRGB,
 158                 .bytesperline = SENSOR_RES_X / 2,
 159                 .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2),
 160         }
 161 };
 162
 163 /* master device state */
 164 struct sur40_state {
 165
 166         struct usb_device *usbdev;
 167         struct device *dev;
 168         struct input_polled_dev *input;
 169
 170         struct v4l2_device v4l2;
 171         struct video_device vdev;
 172         struct mutex lock;
 173         struct v4l2_pix_format pix_fmt;
 174
 175         struct vb2_queue queue;
 176         struct list_head buf_list;
 177         spinlock_t qlock;
 178         int sequence;
 179
 180         struct sur40_data *bulk_in_buffer;
 181         size_t bulk_in_size;
 182         u8 bulk_in_epaddr;
 183
 184         char phys[64];
 185 };
 186
 187 struct sur40_buffer {
 188         struct vb2_v4l2_buffer vb;
 189         struct list_head list;
 190 };
 191
 192 /* forward declarations */
 193 static const struct video_device sur40_video_device;
 194 static const struct vb2_queue sur40_queue;
 195 static void sur40_process_video(struct sur40_state *sur40);
 196
 197 /*
 198  * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT
 199  * here by mistake which is very likely to have corrupted the firmware EEPROM
 200  * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug.
 201  * Should you ever run into a similar problem, the background story to this
 202  * incident and instructions on how to fix the corrupted EEPROM are available
 203  * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html
 204 */
 205
 206 /* command wrapper */
 207 static int sur40_command(struct sur40_state *dev,
 208                          u8 command, u16 index, void *buffer, u16 size)
 209 {
 210         return usb_control_msg(dev->usbdev, usb_rcvctrlpipe(dev->usbdev, 0),
 211                                command,
 212                                USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 213                                0x00, index, buffer, size, 1000);
 214 }
 215
 216 /* Initialization routine, called from sur40_open */
 217 static int sur40_init(struct sur40_state *dev)
 218 {
 219         int result;
 220         u8 *buffer;
 221
 222         buffer = kmalloc(24, GFP_KERNEL);
 223         if (!buffer) {
 224                 result = -ENOMEM;
 225                 goto error;
 226         }
 227
 228         /* stupidly replay the original MS driver init sequence */
 229         result = sur40_command(dev, SUR40_GET_VERSION, 0x00, buffer, 12);
 230         if (result < 0)
 231                 goto error;
 232
 233         result = sur40_command(dev, SUR40_GET_VERSION, 0x01, buffer, 12);
 234         if (result < 0)
 235                 goto error;
 236
 237         result = sur40_command(dev, SUR40_GET_VERSION, 0x02, buffer, 12);
 238         if (result < 0)
 239                 goto error;
 240
 241         result = sur40_command(dev, SUR40_UNKNOWN2,    0x00, buffer, 24);
 242         if (result < 0)
 243                 goto error;
 244
 245         result = sur40_command(dev, SUR40_UNKNOWN1,    0x00, buffer,  5);
 246         if (result < 0)
 247                 goto error;
 248
 249         result = sur40_command(dev, SUR40_GET_VERSION, 0x03, buffer, 12);
 250
 251         /*
 252          * Discard the result buffer - no known data inside except
 253          * some version strings, maybe extract these sometime...
 254          */
 255 error:
 256         kfree(buffer);
 257         return result;
 258 }
 259
 260 /*
 261  * Callback routines from input_polled_dev
 262  */
 263
 264 /* Enable the device, polling will now start. */
 265 static void sur40_open(struct input_polled_dev *polldev)
 266 {
 267         struct sur40_state *sur40 = polldev->private;
 268
 269         dev_dbg(sur40->dev, "open\n");
 270         sur40_init(sur40);
 271 }
 272
 273 /* Disable device, polling has stopped. */
 274 static void sur40_close(struct input_polled_dev *polldev)
 275 {
 276         struct sur40_state *sur40 = polldev->private;
 277
 278         dev_dbg(sur40->dev, "close\n");
 279         /*
 280          * There is no known way to stop the device, so we simply
 281          * stop polling.
 282          */
 283 }
 284
 285 /*
 286  * This function is called when a whole contact has been processed,
 287  * so that it can assign it to a slot and store the data there.
 288  */
 289 static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input)
 290 {
 291         int wide, major, minor;
 292
 293         int bb_size_x = le16_to_cpu(blob->bb_size_x);
 294         int bb_size_y = le16_to_cpu(blob->bb_size_y);
 295
 296         int pos_x = le16_to_cpu(blob->pos_x);
 297         int pos_y = le16_to_cpu(blob->pos_y);
 298
 299         int ctr_x = le16_to_cpu(blob->ctr_x);
 300         int ctr_y = le16_to_cpu(blob->ctr_y);
 301
 302         int slotnum = input_mt_get_slot_by_key(input, blob->blob_id);
 303         if (slotnum < 0 || slotnum >= MAX_CONTACTS)
 304                 return;
 305
 306         input_mt_slot(input, slotnum);
 307         input_mt_report_slot_state(input, MT_TOOL_FINGER, 1);
 308         wide = (bb_size_x > bb_size_y);
 309         major = max(bb_size_x, bb_size_y);
 310         minor = min(bb_size_x, bb_size_y);
 311
 312         input_report_abs(input, ABS_MT_POSITION_X, pos_x);
 313         input_report_abs(input, ABS_MT_POSITION_Y, pos_y);
 314         input_report_abs(input, ABS_MT_TOOL_X, ctr_x);
 315         input_report_abs(input, ABS_MT_TOOL_Y, ctr_y);
 316
 317         /* TODO: use a better orientation measure */
 318         input_report_abs(input, ABS_MT_ORIENTATION, wide);
 319         input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
 320         input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
 321 }
 322
 323 /* core function: poll for new input data */
 324 static void sur40_poll(struct input_polled_dev *polldev)
 325 {
 326         struct sur40_state *sur40 = polldev->private;
 327         struct input_dev *input = polldev->input;
 328         int result, bulk_read, need_blobs, packet_blobs, i;
 329         u32 uninitialized_var(packet_id);
 330
 331         struct sur40_header *header = &sur40->bulk_in_buffer->header;
 332         struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0];
 333
 334         dev_dbg(sur40->dev, "poll\n");
 335
 336         need_blobs = -1;
 337
 338         do {
 339
 340                 /* perform a blocking bulk read to get data from the device */
 341                 result = usb_bulk_msg(sur40->usbdev,
 342                         usb_rcvbulkpipe(sur40->usbdev, sur40->bulk_in_epaddr),
 343                         sur40->bulk_in_buffer, sur40->bulk_in_size,
 344                         &bulk_read, 1000);
 345
 346                 dev_dbg(sur40->dev, "received %d bytes\n", bulk_read);
 347
 348                 if (result < 0) {
 349                         dev_err(sur40->dev, "error in usb_bulk_read\n");
 350                         return;
 351                 }
 352
 353                 result = bulk_read - sizeof(struct sur40_header);
 354
 355                 if (result % sizeof(struct sur40_blob) != 0) {
 356                         dev_err(sur40->dev, "transfer size mismatch\n");
 357                         return;
 358                 }
 359
 360                 /* first packet? */
 361                 if (need_blobs == -1) {
 362                         need_blobs = le16_to_cpu(header->count);
 363                         dev_dbg(sur40->dev, "need %d blobs\n", need_blobs);
 364                         packet_id = le32_to_cpu(header->packet_id);
 365                 }
 366
 367                 /*
 368                  * Sanity check. when video data is also being retrieved, the
 369                  * packet ID will usually increase in the middle of a series
 370                  * instead of at the end.
 371                  */
 372                 if (packet_id != le32_to_cpu(header->packet_id))
 373                         dev_dbg(sur40->dev, "packet ID mismatch\n");
 374
 375                 packet_blobs = result / sizeof(struct sur40_blob);
 376                 dev_dbg(sur40->dev, "received %d blobs\n", packet_blobs);
 377
 378                 /* packets always contain at least 4 blobs, even if empty */
 379                 if (packet_blobs > need_blobs)
 380                         packet_blobs = need_blobs;
 381
 382                 for (i = 0; i < packet_blobs; i++) {
 383                         need_blobs--;
 384                         dev_dbg(sur40->dev, "processing blob\n");
 385                         sur40_report_blob(&(inblob[i]), input);
 386                 }
 387
 388         } while (need_blobs > 0);
 389
 390         input_mt_sync_frame(input);
 391         input_sync(input);
 392
 393         sur40_process_video(sur40);
 394 }
 395
 396 /* deal with video data */
 397 static void sur40_process_video(struct sur40_state *sur40)
 398 {
 399
 400         struct sur40_image_header *img = (void *)(sur40->bulk_in_buffer);
 401         struct sur40_buffer *new_buf;
 402         struct usb_sg_request sgr;
 403         struct sg_table *sgt;
 404         int result, bulk_read;
 405
 406         if (!vb2_start_streaming_called(&sur40->queue))
 407                 return;
 408
 409         /* get a new buffer from the list */
 410         spin_lock(&sur40->qlock);
 411         if (list_empty(&sur40->buf_list)) {
 412                 dev_dbg(sur40->dev, "buffer queue empty\n");
 413                 spin_unlock(&sur40->qlock);
 414                 return;
 415         }
 416         new_buf = list_entry(sur40->buf_list.next, struct sur40_buffer, list);
 417         list_del(&new_buf->list);
 418         spin_unlock(&sur40->qlock);
 419
 420         dev_dbg(sur40->dev, "buffer acquired\n");
 421
 422         /* retrieve data via bulk read */
 423         result = usb_bulk_msg(sur40->usbdev,
 424                         usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT),
 425                         sur40->bulk_in_buffer, sur40->bulk_in_size,
 426                         &bulk_read, 1000);
 427
 428         if (result < 0) {
 429                 dev_err(sur40->dev, "error in usb_bulk_read\n");
 430                 goto err_poll;
 431         }
 432
 433         if (bulk_read != sizeof(struct sur40_image_header)) {
 434                 dev_err(sur40->dev, "received %d bytes (%zd expected)\n",
 435                         bulk_read, sizeof(struct sur40_image_header));
 436                 goto err_poll;
 437         }
 438
 439         if (le32_to_cpu(img->magic) != VIDEO_HEADER_MAGIC) {
 440                 dev_err(sur40->dev, "image magic mismatch\n");
 441                 goto err_poll;
 442         }
 443
 444         if (le32_to_cpu(img->size) != sur40->pix_fmt.sizeimage) {
 445                 dev_err(sur40->dev, "image size mismatch\n");
 446                 goto err_poll;
 447         }
 448
 449         dev_dbg(sur40->dev, "header acquired\n");
 450
 451         sgt = vb2_dma_sg_plane_desc(&new_buf->vb.vb2_buf, 0);
 452
 453         result = usb_sg_init(&sgr, sur40->usbdev,
 454                 usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 0,
 455                 sgt->sgl, sgt->nents, sur40->pix_fmt.sizeimage, 0);
 456         if (result < 0) {
 457                 dev_err(sur40->dev, "error %d in usb_sg_init\n", result);
 458                 goto err_poll;
 459         }
 460
 461         usb_sg_wait(&sgr);
 462         if (sgr.status < 0) {
 463                 dev_err(sur40->dev, "error %d in usb_sg_wait\n", sgr.status);
 464                 goto err_poll;
 465         }
 466
 467         dev_dbg(sur40->dev, "image acquired\n");
 468
 469         /* return error if streaming was stopped in the meantime */
 470         if (sur40->sequence == -1)
 471                 return;
 472
 473         /* mark as finished */
 474         new_buf->vb.vb2_buf.timestamp = ktime_get_ns();
 475         new_buf->vb.sequence = sur40->sequence++;
 476         new_buf->vb.field = V4L2_FIELD_NONE;
 477         vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
 478         dev_dbg(sur40->dev, "buffer marked done\n");
 479         return;
 480
 481 err_poll:
 482         vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
 483 }
 484
 485 /* Initialize input device parameters. */
 486 static void sur40_input_setup(struct input_dev *input_dev)
 487 {
 488         __set_bit(EV_KEY, input_dev->evbit);
 489         __set_bit(EV_ABS, input_dev->evbit);
 490
 491         input_set_abs_params(input_dev, ABS_MT_POSITION_X,
 492                              0, SENSOR_RES_X, 0, 0);
 493         input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
 494                              0, SENSOR_RES_Y, 0, 0);
 495
 496         input_set_abs_params(input_dev, ABS_MT_TOOL_X,
 497                              0, SENSOR_RES_X, 0, 0);
 498         input_set_abs_params(input_dev, ABS_MT_TOOL_Y,
 499                              0, SENSOR_RES_Y, 0, 0);
 500
 501         /* max value unknown, but major/minor axis
 502          * can never be larger than screen */
 503         input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
 504                              0, SENSOR_RES_X, 0, 0);
 505         input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR,
 506                              0, SENSOR_RES_Y, 0, 0);
 507
 508         input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
 509
 510         input_mt_init_slots(input_dev, MAX_CONTACTS,
 511                             INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
 512 }
 513
 514 /* Check candidate USB interface. */
 515 static int sur40_probe(struct usb_interface *interface,
 516                        const struct usb_device_id *id)
 517 {
 518         struct usb_device *usbdev = interface_to_usbdev(interface);
 519         struct sur40_state *sur40;
 520         struct usb_host_interface *iface_desc;
 521         struct usb_endpoint_descriptor *endpoint;
 522         struct input_polled_dev *poll_dev;
 523         int error;
 524
 525         /* Check if we really have the right interface. */
 526         iface_desc = &interface->altsetting[0];
 527         if (iface_desc->desc.bInterfaceClass != 0xFF)
 528                 return -ENODEV;
 529
 530         if (iface_desc->desc.bNumEndpoints < 5)
 531                 return -ENODEV;
 532
 533         /* Use endpoint #4 (0x86). */
 534         endpoint = &iface_desc->endpoint[4].desc;
 535         if (endpoint->bEndpointAddress != TOUCH_ENDPOINT)
 536                 return -ENODEV;
 537
 538         /* Allocate memory for our device state and initialize it. */
 539         sur40 = kzalloc(sizeof(struct sur40_state), GFP_KERNEL);
 540         if (!sur40)
 541                 return -ENOMEM;
 542
 543         poll_dev = input_allocate_polled_device();
 544         if (!poll_dev) {
 545                 error = -ENOMEM;
 546                 goto err_free_dev;
 547         }
 548
 549         /* initialize locks/lists */
 550         INIT_LIST_HEAD(&sur40->buf_list);
 551         spin_lock_init(&sur40->qlock);
 552         mutex_init(&sur40->lock);
 553
 554         /* Set up polled input device control structure */
 555         poll_dev->private = sur40;
 556         poll_dev->poll_interval = POLL_INTERVAL;
 557         poll_dev->open = sur40_open;
 558         poll_dev->poll = sur40_poll;
 559         poll_dev->close = sur40_close;
 560
 561         /* Set up regular input device structure */
 562         sur40_input_setup(poll_dev->input);
 563
 564         poll_dev->input->name = DRIVER_LONG;
 565         usb_to_input_id(usbdev, &poll_dev->input->id);
 566         usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys));
 567         strlcat(sur40->phys, "/input0", sizeof(sur40->phys));
 568         poll_dev->input->phys = sur40->phys;
 569         poll_dev->input->dev.parent = &interface->dev;
 570
 571         sur40->usbdev = usbdev;
 572         sur40->dev = &interface->dev;
 573         sur40->input = poll_dev;
 574
 575         /* use the bulk-in endpoint tested above */
 576         sur40->bulk_in_size = usb_endpoint_maxp(endpoint);
 577         sur40->bulk_in_epaddr = endpoint->bEndpointAddress;
 578         sur40->bulk_in_buffer = kmalloc(sur40->bulk_in_size, GFP_KERNEL);
 579         if (!sur40->bulk_in_buffer) {
 580                 dev_err(&interface->dev, "Unable to allocate input buffer.");
 581                 error = -ENOMEM;
 582                 goto err_free_polldev;
 583         }
 584
 585         /* register the polled input device */
 586         error = input_register_polled_device(poll_dev);
 587         if (error) {
 588                 dev_err(&interface->dev,
 589                         "Unable to register polled input device.");
 590                 goto err_free_buffer;
 591         }
 592
 593         /* register the video master device */
 594         snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG);
 595         error = v4l2_device_register(sur40->dev, &sur40->v4l2);
 596         if (error) {
 597                 dev_err(&interface->dev,
 598                         "Unable to register video master device.");
 599                 goto err_unreg_v4l2;
 600         }
 601
 602         /* initialize the lock and subdevice */
 603         sur40->queue = sur40_queue;
 604         sur40->queue.drv_priv = sur40;
 605         sur40->queue.lock = &sur40->lock;
 606         sur40->queue.dev = sur40->dev;
 607
 608         /* initialize the queue */
 609         error = vb2_queue_init(&sur40->queue);
 610         if (error)
 611                 goto err_unreg_v4l2;
 612
 613         sur40->pix_fmt = sur40_pix_format[0];
 614         sur40->vdev = sur40_video_device;
 615         sur40->vdev.v4l2_dev = &sur40->v4l2;
 616         sur40->vdev.lock = &sur40->lock;
 617         sur40->vdev.queue = &sur40->queue;
 618         video_set_drvdata(&sur40->vdev, sur40);
 619
 620         error = video_register_device(&sur40->vdev, VFL_TYPE_TOUCH, -1);
 621         if (error) {
 622                 dev_err(&interface->dev,
 623                         "Unable to register video subdevice.");
 624                 goto err_unreg_video;
 625         }
 626
 627         /* we can register the device now, as it is ready */
 628         usb_set_intfdata(interface, sur40);
 629         dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC);
 630
 631         return 0;
 632
 633 err_unreg_video:
 634         video_unregister_device(&sur40->vdev);
 635 err_unreg_v4l2:
 636         v4l2_device_unregister(&sur40->v4l2);
 637 err_free_buffer:
 638         kfree(sur40->bulk_in_buffer);
 639 err_free_polldev:
 640         input_free_polled_device(sur40->input);
 641 err_free_dev:
 642         kfree(sur40);
 643
 644         return error;
 645 }
 646
 647 /* Unregister device & clean up. */
 648 static void sur40_disconnect(struct usb_interface *interface)
 649 {
 650         struct sur40_state *sur40 = usb_get_intfdata(interface);
 651
 652         video_unregister_device(&sur40->vdev);
 653         v4l2_device_unregister(&sur40->v4l2);
 654
 655         input_unregister_polled_device(sur40->input);
 656         input_free_polled_device(sur40->input);
 657         kfree(sur40->bulk_in_buffer);
 658         kfree(sur40);
 659
 660         usb_set_intfdata(interface, NULL);
 661         dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC);
 662 }
 663
 664 /*
 665  * Setup the constraints of the queue: besides setting the number of planes
 666  * per buffer and the size and allocation context of each plane, it also
 667  * checks if sufficient buffers have been allocated. Usually 3 is a good
 668  * minimum number: many DMA engines need a minimum of 2 buffers in the
 669  * queue and you need to have another available for userspace processing.
 670  */
 671 static int sur40_queue_setup(struct vb2_queue *q,
 672                        unsigned int *nbuffers, unsigned int *nplanes,
 673                        unsigned int sizes[], struct device *alloc_devs[])
 674 {
 675         struct sur40_state *sur40 = vb2_get_drv_priv(q);
 676
 677         if (q->num_buffers + *nbuffers < 3)
 678                 *nbuffers = 3 - q->num_buffers;
 679
 680         if (*nplanes)
 681                 return sizes[0] < sur40->pix_fmt.sizeimage ? -EINVAL : 0;
 682
 683         *nplanes = 1;
 684         sizes[0] = sur40->pix_fmt.sizeimage;
 685
 686         return 0;
 687 }
 688
 689 /*
 690  * Prepare the buffer for queueing to the DMA engine: check and set the
 691  * payload size.
 692  */
 693 static int sur40_buffer_prepare(struct vb2_buffer *vb)
 694 {
 695         struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
 696         unsigned long size = sur40->pix_fmt.sizeimage;
 697
 698         if (vb2_plane_size(vb, 0) < size) {
 699                 dev_err(&sur40->usbdev->dev, "buffer too small (%lu < %lu)\n",
 700                          vb2_plane_size(vb, 0), size);
 701                 return -EINVAL;
 702         }
 703
 704         vb2_set_plane_payload(vb, 0, size);
 705         return 0;
 706 }
 707
 708 /*
 709  * Queue this buffer to the DMA engine.
 710  */
 711 static void sur40_buffer_queue(struct vb2_buffer *vb)
 712 {
 713         struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
 714         struct sur40_buffer *buf = (struct sur40_buffer *)vb;
 715
 716         spin_lock(&sur40->qlock);
 717         list_add_tail(&buf->list, &sur40->buf_list);
 718         spin_unlock(&sur40->qlock);
 719 }
 720
 721 static void return_all_buffers(struct sur40_state *sur40,
 722                                enum vb2_buffer_state state)
 723 {
 724         struct sur40_buffer *buf, *node;
 725
 726         spin_lock(&sur40->qlock);
 727         list_for_each_entry_safe(buf, node, &sur40->buf_list, list) {
 728                 vb2_buffer_done(&buf->vb.vb2_buf, state);
 729                 list_del(&buf->list);
 730         }
 731         spin_unlock(&sur40->qlock);
 732 }
 733
 734 /*
 735  * Start streaming. First check if the minimum number of buffers have been
 736  * queued. If not, then return -ENOBUFS and the vb2 framework will call
 737  * this function again the next time a buffer has been queued until enough
 738  * buffers are available to actually start the DMA engine.
 739  */
 740 static int sur40_start_streaming(struct vb2_queue *vq, unsigned int count)
 741 {
 742         struct sur40_state *sur40 = vb2_get_drv_priv(vq);
 743
 744         sur40->sequence = 0;
 745         return 0;
 746 }
 747
 748 /*
 749  * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
 750  * and passed on to the vb2 framework marked as STATE_ERROR.
 751  */
 752 static void sur40_stop_streaming(struct vb2_queue *vq)
 753 {
 754         struct sur40_state *sur40 = vb2_get_drv_priv(vq);
 755         vb2_wait_for_all_buffers(vq);
 756         sur40->sequence = -1;
 757
 758         /* Release all active buffers */
 759         return_all_buffers(sur40, VB2_BUF_STATE_ERROR);
 760 }
 761
 762 /* V4L ioctl */
 763 static int sur40_vidioc_querycap(struct file *file, void *priv,
 764                                  struct v4l2_capability *cap)
 765 {
 766         struct sur40_state *sur40 = video_drvdata(file);
 767
 768         strlcpy(cap->driver, DRIVER_SHORT, sizeof(cap->driver));
 769         strlcpy(cap->card, DRIVER_LONG, sizeof(cap->card));
 770         usb_make_path(sur40->usbdev, cap->bus_info, sizeof(cap->bus_info));
 771         cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_TOUCH |
 772                 V4L2_CAP_READWRITE |
 773                 V4L2_CAP_STREAMING;
 774         cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
 775         return 0;
 776 }
 777
 778 static int sur40_vidioc_enum_input(struct file *file, void *priv,
 779                                    struct v4l2_input *i)
 780 {
 781         if (i->index != 0)
 782                 return -EINVAL;
 783         i->type = V4L2_INPUT_TYPE_TOUCH;
 784         i->std = V4L2_STD_UNKNOWN;
 785         strlcpy(i->name, "In-Cell Sensor", sizeof(i->name));
 786         i->capabilities = 0;
 787         return 0;
 788 }
 789
 790 static int sur40_vidioc_s_input(struct file *file, void *priv, unsigned int i)
 791 {
 792         return (i == 0) ? 0 : -EINVAL;
 793 }
 794
 795 static int sur40_vidioc_g_input(struct file *file, void *priv, unsigned int *i)
 796 {
 797         *i = 0;
 798         return 0;
 799 }
 800
 801 static int sur40_vidioc_try_fmt(struct file *file, void *priv,
 802                             struct v4l2_format *f)
 803 {
 804         switch (f->fmt.pix.pixelformat) {
 805         case V4L2_PIX_FMT_GREY:
 806                 f->fmt.pix = sur40_pix_format[1];
 807                 break;
 808
 809         default:
 810                 f->fmt.pix = sur40_pix_format[0];
 811                 break;
 812         }
 813
 814         return 0;
 815 }
 816
 817 static int sur40_vidioc_s_fmt(struct file *file, void *priv,
 818                             struct v4l2_format *f)
 819 {
 820         struct sur40_state *sur40 = video_drvdata(file);
 821
 822         switch (f->fmt.pix.pixelformat) {
 823         case V4L2_PIX_FMT_GREY:
 824                 sur40->pix_fmt = sur40_pix_format[1];
 825                 break;
 826
 827         default:
 828                 sur40->pix_fmt = sur40_pix_format[0];
 829                 break;
 830         }
 831
 832         f->fmt.pix = sur40->pix_fmt;
 833         return 0;
 834 }
 835
 836 static int sur40_vidioc_g_fmt(struct file *file, void *priv,
 837                             struct v4l2_format *f)
 838 {
 839         struct sur40_state *sur40 = video_drvdata(file);
 840
 841         f->fmt.pix = sur40->pix_fmt;
 842         return 0;
 843 }
 844
 845 static int sur40_ioctl_parm(struct file *file, void *priv,
 846                             struct v4l2_streamparm *p)
 847 {
 848         if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 849                 return -EINVAL;
 850
 851         p->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
 852         p->parm.capture.timeperframe.numerator = 1;
 853         p->parm.capture.timeperframe.denominator = 60;
 854         p->parm.capture.readbuffers = 3;
 855         return 0;
 856 }
 857
 858 static int sur40_vidioc_enum_fmt(struct file *file, void *priv,
 859                                  struct v4l2_fmtdesc *f)
 860 {
 861         if (f->index >= ARRAY_SIZE(sur40_pix_format))
 862                 return -EINVAL;
 863
 864         f->pixelformat = sur40_pix_format[f->index].pixelformat;
 865         f->flags = 0;
 866         return 0;
 867 }
 868
 869 static int sur40_vidioc_enum_framesizes(struct file *file, void *priv,
 870                                         struct v4l2_frmsizeenum *f)
 871 {
 872         struct sur40_state *sur40 = video_drvdata(file);
 873
 874         if ((f->index != 0) || ((f->pixel_format != V4L2_TCH_FMT_TU08)
 875                 && (f->pixel_format != V4L2_PIX_FMT_GREY)))
 876                 return -EINVAL;
 877
 878         f->type = V4L2_FRMSIZE_TYPE_DISCRETE;
 879         f->discrete.width  = sur40->pix_fmt.width;
 880         f->discrete.height = sur40->pix_fmt.height;
 881         return 0;
 882 }
 883
 884 static int sur40_vidioc_enum_frameintervals(struct file *file, void *priv,
 885                                             struct v4l2_frmivalenum *f)
 886 {
 887         struct sur40_state *sur40 = video_drvdata(file);
 888
 889         if ((f->index > 0) || ((f->pixel_format != V4L2_TCH_FMT_TU08)
 890                 && (f->pixel_format != V4L2_PIX_FMT_GREY))
 891                 || (f->width  != sur40->pix_fmt.width)
 892                 || (f->height != sur40->pix_fmt.height))
 893                 return -EINVAL;
 894
 895         f->type = V4L2_FRMIVAL_TYPE_DISCRETE;
 896         f->discrete.denominator  = 60;
 897         f->discrete.numerator = 1;
 898         return 0;
 899 }
 900
 901
 902 static const struct usb_device_id sur40_table[] = {
 903         { USB_DEVICE(ID_MICROSOFT, ID_SUR40) },  /* Samsung SUR40 */
 904         { }                                      /* terminating null entry */
 905 };
 906 MODULE_DEVICE_TABLE(usb, sur40_table);
 907
 908 /* V4L2 structures */
 909 static const struct vb2_ops sur40_queue_ops = {
 910         .queue_setup            = sur40_queue_setup,
 911         .buf_prepare            = sur40_buffer_prepare,
 912         .buf_queue              = sur40_buffer_queue,
 913         .start_streaming        = sur40_start_streaming,
 914         .stop_streaming         = sur40_stop_streaming,
 915         .wait_prepare           = vb2_ops_wait_prepare,
 916         .wait_finish            = vb2_ops_wait_finish,
 917 };
 918
 919 static const struct vb2_queue sur40_queue = {
 920         .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
 921         /*
 922          * VB2_USERPTR in currently not enabled: passing a user pointer to
 923          * dma-sg will result in segment sizes that are not a multiple of
 924          * 512 bytes, which is required by the host controller.
 925         */
 926         .io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF,
 927         .buf_struct_size = sizeof(struct sur40_buffer),
 928         .ops = &sur40_queue_ops,
 929         .mem_ops = &vb2_dma_sg_memops,
 930         .timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC,
 931         .min_buffers_needed = 3,
 932 };
 933
 934 static const struct v4l2_file_operations sur40_video_fops = {
 935         .owner = THIS_MODULE,
 936         .open = v4l2_fh_open,
 937         .release = vb2_fop_release,
 938         .unlocked_ioctl = video_ioctl2,
 939         .read = vb2_fop_read,
 940         .mmap = vb2_fop_mmap,
 941         .poll = vb2_fop_poll,
 942 };
 943
 944 static const struct v4l2_ioctl_ops sur40_video_ioctl_ops = {
 945
 946         .vidioc_querycap        = sur40_vidioc_querycap,
 947
 948         .vidioc_enum_fmt_vid_cap = sur40_vidioc_enum_fmt,
 949         .vidioc_try_fmt_vid_cap = sur40_vidioc_try_fmt,
 950         .vidioc_s_fmt_vid_cap   = sur40_vidioc_s_fmt,
 951         .vidioc_g_fmt_vid_cap   = sur40_vidioc_g_fmt,
 952
 953         .vidioc_enum_framesizes = sur40_vidioc_enum_framesizes,
 954         .vidioc_enum_frameintervals = sur40_vidioc_enum_frameintervals,
 955
 956         .vidioc_g_parm = sur40_ioctl_parm,
 957         .vidioc_s_parm = sur40_ioctl_parm,
 958
 959         .vidioc_enum_input      = sur40_vidioc_enum_input,
 960         .vidioc_g_input         = sur40_vidioc_g_input,
 961         .vidioc_s_input         = sur40_vidioc_s_input,
 962
 963         .vidioc_reqbufs         = vb2_ioctl_reqbufs,
 964         .vidioc_create_bufs     = vb2_ioctl_create_bufs,
 965         .vidioc_querybuf        = vb2_ioctl_querybuf,
 966         .vidioc_qbuf            = vb2_ioctl_qbuf,
 967         .vidioc_dqbuf           = vb2_ioctl_dqbuf,
 968         .vidioc_expbuf          = vb2_ioctl_expbuf,
 969
 970         .vidioc_streamon        = vb2_ioctl_streamon,
 971         .vidioc_streamoff       = vb2_ioctl_streamoff,
 972 };
 973
 974 static const struct video_device sur40_video_device = {
 975         .name = DRIVER_LONG,
 976         .fops = &sur40_video_fops,
 977         .ioctl_ops = &sur40_video_ioctl_ops,
 978         .release = video_device_release_empty,
 979 };
 980
 981 /* USB-specific object needed to register this driver with the USB subsystem. */
 982 static struct usb_driver sur40_driver = {
 983         .name = DRIVER_SHORT,
 984         .probe = sur40_probe,
 985         .disconnect = sur40_disconnect,
 986         .id_table = sur40_table,
 987 };
 988
 989 module_usb_driver(sur40_driver);
 990
 991 MODULE_AUTHOR(DRIVER_AUTHOR);
 992 MODULE_DESCRIPTION(DRIVER_DESC);
 993 MODULE_LICENSE("GPL");