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 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");