linux/drivers/input/touchscreen/sur40.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Surface2.0/SUR40/PixelSense input driver
   4 *
   5 * Copyright (c) 2014 by Florian 'floe' Echtler <floe@butterbrot.org>
   6 *
   7 * Derived from the USB Skeleton driver 1.1,
   8 * Copyright (c) 2003 Greg Kroah-Hartman (greg@kroah.com)
   9 *
  10 * and from the Apple USB BCM5974 multitouch driver,
  11 * Copyright (c) 2008 Henrik Rydberg (rydberg@euromail.se)
  12 *
  13 * and from the generic hid-multitouch driver,
  14 * Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
  15 *
  16 * and from the v4l2-pci-skeleton driver,
  17 * Copyright (c) Copyright 2014 Cisco Systems, Inc.
  18 */
  19
  20#include <linux/kernel.h>
  21#include <linux/errno.h>
  22#include <linux/delay.h>
  23#include <linux/init.h>
  24#include <linux/slab.h>
  25#include <linux/module.h>
  26#include <linux/completion.h>
  27#include <linux/uaccess.h>
  28#include <linux/usb.h>
  29#include <linux/printk.h>
  30#include <linux/input.h>
  31#include <linux/input/mt.h>
  32#include <linux/usb/input.h>
  33#include <linux/videodev2.h>
  34#include <media/v4l2-device.h>
  35#include <media/v4l2-dev.h>
  36#include <media/v4l2-ioctl.h>
  37#include <media/v4l2-ctrls.h>
  38#include <media/videobuf2-v4l2.h>
  39#include <media/videobuf2-dma-sg.h>
  40
  41/* read 512 bytes from endpoint 0x86 -> get header + blobs */
  42struct sur40_header {
  43
  44        __le16 type;       /* always 0x0001 */
  45        __le16 count;      /* count of blobs (if 0: continue prev. packet) */
  46
  47        __le32 packet_id;  /* unique ID for all packets in one frame */
  48
  49        __le32 timestamp;  /* milliseconds (inc. by 16 or 17 each frame) */
  50        __le32 unknown;    /* "epoch?" always 02/03 00 00 00 */
  51
  52} __packed;
  53
  54struct sur40_blob {
  55
  56        __le16 blob_id;
  57
  58        u8 action;         /* 0x02 = enter/exit, 0x03 = update (?) */
  59        u8 type;           /* bitmask (0x01 blob,  0x02 touch, 0x04 tag) */
  60
  61        __le16 bb_pos_x;   /* upper left corner of bounding box */
  62        __le16 bb_pos_y;
  63
  64        __le16 bb_size_x;  /* size of bounding box */
  65        __le16 bb_size_y;
  66
  67        __le16 pos_x;      /* finger tip position */
  68        __le16 pos_y;
  69
  70        __le16 ctr_x;      /* centroid position */
  71        __le16 ctr_y;
  72
  73        __le16 axis_x;     /* somehow related to major/minor axis, mostly: */
  74        __le16 axis_y;     /* axis_x == bb_size_y && axis_y == bb_size_x */
  75
  76        __le32 angle;      /* orientation in radians relative to x axis -
  77                              actually an IEEE754 float, don't use in kernel */
  78
  79        __le32 area;       /* size in pixels/pressure (?) */
  80
  81        u8 padding[24];
  82
  83        __le32 tag_id;     /* valid when type == 0x04 (SUR40_TAG) */
  84        __le32 unknown;
  85
  86} __packed;
  87
  88/* combined header/blob data */
  89struct 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 */
  96struct 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_ACCEL_CAPS  0xb3 /*  5 bytes           */
 137#define SUR40_SENSOR_CAPS 0xc1 /* 24 bytes           */
 138
 139#define SUR40_POKE        0xc5 /* poke register byte */
 140#define SUR40_PEEK        0xc4 /* 48 bytes registers */
 141
 142#define SUR40_GET_STATE   0xc5 /*  4 bytes state (?) */
 143#define SUR40_GET_SENSORS 0xb1 /*  8 bytes sensors   */
 144
 145#define SUR40_BLOB      0x01
 146#define SUR40_TOUCH     0x02
 147#define SUR40_TAG       0x04
 148
 149/* video controls */
 150#define SUR40_BRIGHTNESS_MAX 0xff
 151#define SUR40_BRIGHTNESS_MIN 0x00
 152#define SUR40_BRIGHTNESS_DEF 0xff
 153
 154#define SUR40_CONTRAST_MAX 0x0f
 155#define SUR40_CONTRAST_MIN 0x00
 156#define SUR40_CONTRAST_DEF 0x0a
 157
 158#define SUR40_GAIN_MAX 0x09
 159#define SUR40_GAIN_MIN 0x00
 160#define SUR40_GAIN_DEF 0x08
 161
 162#define SUR40_BACKLIGHT_MAX 0x01
 163#define SUR40_BACKLIGHT_MIN 0x00
 164#define SUR40_BACKLIGHT_DEF 0x01
 165
 166#define sur40_str(s) #s
 167#define SUR40_PARAM_RANGE(lo, hi) " (range " sur40_str(lo) "-" sur40_str(hi) ")"
 168
 169/* module parameters */
 170static uint brightness = SUR40_BRIGHTNESS_DEF;
 171module_param(brightness, uint, 0644);
 172MODULE_PARM_DESC(brightness, "set initial brightness"
 173        SUR40_PARAM_RANGE(SUR40_BRIGHTNESS_MIN, SUR40_BRIGHTNESS_MAX));
 174static uint contrast = SUR40_CONTRAST_DEF;
 175module_param(contrast, uint, 0644);
 176MODULE_PARM_DESC(contrast, "set initial contrast"
 177        SUR40_PARAM_RANGE(SUR40_CONTRAST_MIN, SUR40_CONTRAST_MAX));
 178static uint gain = SUR40_GAIN_DEF;
 179module_param(gain, uint, 0644);
 180MODULE_PARM_DESC(gain, "set initial gain"
 181        SUR40_PARAM_RANGE(SUR40_GAIN_MIN, SUR40_GAIN_MAX));
 182
 183static const struct v4l2_pix_format sur40_pix_format[] = {
 184        {
 185                .pixelformat = V4L2_TCH_FMT_TU08,
 186                .width  = SENSOR_RES_X / 2,
 187                .height = SENSOR_RES_Y / 2,
 188                .field = V4L2_FIELD_NONE,
 189                .colorspace = V4L2_COLORSPACE_RAW,
 190                .bytesperline = SENSOR_RES_X / 2,
 191                .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2),
 192        },
 193        {
 194                .pixelformat = V4L2_PIX_FMT_GREY,
 195                .width  = SENSOR_RES_X / 2,
 196                .height = SENSOR_RES_Y / 2,
 197                .field = V4L2_FIELD_NONE,
 198                .colorspace = V4L2_COLORSPACE_RAW,
 199                .bytesperline = SENSOR_RES_X / 2,
 200                .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2),
 201        }
 202};
 203
 204/* master device state */
 205struct sur40_state {
 206
 207        struct usb_device *usbdev;
 208        struct device *dev;
 209        struct input_dev *input;
 210
 211        struct v4l2_device v4l2;
 212        struct video_device vdev;
 213        struct mutex lock;
 214        struct v4l2_pix_format pix_fmt;
 215        struct v4l2_ctrl_handler hdl;
 216
 217        struct vb2_queue queue;
 218        struct list_head buf_list;
 219        spinlock_t qlock;
 220        int sequence;
 221
 222        struct sur40_data *bulk_in_buffer;
 223        size_t bulk_in_size;
 224        u8 bulk_in_epaddr;
 225        u8 vsvideo;
 226
 227        char phys[64];
 228};
 229
 230struct sur40_buffer {
 231        struct vb2_v4l2_buffer vb;
 232        struct list_head list;
 233};
 234
 235/* forward declarations */
 236static const struct video_device sur40_video_device;
 237static const struct vb2_queue sur40_queue;
 238static void sur40_process_video(struct sur40_state *sur40);
 239static int sur40_s_ctrl(struct v4l2_ctrl *ctrl);
 240
 241static const struct v4l2_ctrl_ops sur40_ctrl_ops = {
 242        .s_ctrl = sur40_s_ctrl,
 243};
 244
 245/*
 246 * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT
 247 * here by mistake which is very likely to have corrupted the firmware EEPROM
 248 * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug.
 249 * Should you ever run into a similar problem, the background story to this
 250 * incident and instructions on how to fix the corrupted EEPROM are available
 251 * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html
 252*/
 253
 254/* command wrapper */
 255static int sur40_command(struct sur40_state *dev,
 256                         u8 command, u16 index, void *buffer, u16 size)
 257{
 258        return usb_control_msg(dev->usbdev, usb_rcvctrlpipe(dev->usbdev, 0),
 259                               command,
 260                               USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 261                               0x00, index, buffer, size, 1000);
 262}
 263
 264/* poke a byte in the panel register space */
 265static int sur40_poke(struct sur40_state *dev, u8 offset, u8 value)
 266{
 267        int result;
 268        u8 index = 0x96; // 0xae for permanent write
 269
 270        result = usb_control_msg(dev->usbdev, usb_sndctrlpipe(dev->usbdev, 0),
 271                SUR40_POKE, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 272                0x32, index, NULL, 0, 1000);
 273        if (result < 0)
 274                goto error;
 275        msleep(5);
 276
 277        result = usb_control_msg(dev->usbdev, usb_sndctrlpipe(dev->usbdev, 0),
 278                SUR40_POKE, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 279                0x72, offset, NULL, 0, 1000);
 280        if (result < 0)
 281                goto error;
 282        msleep(5);
 283
 284        result = usb_control_msg(dev->usbdev, usb_sndctrlpipe(dev->usbdev, 0),
 285                SUR40_POKE, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 286                0xb2, value, NULL, 0, 1000);
 287        if (result < 0)
 288                goto error;
 289        msleep(5);
 290
 291error:
 292        return result;
 293}
 294
 295static int sur40_set_preprocessor(struct sur40_state *dev, u8 value)
 296{
 297        u8 setting_07[2] = { 0x01, 0x00 };
 298        u8 setting_17[2] = { 0x85, 0x80 };
 299        int result;
 300
 301        if (value > 1)
 302                return -ERANGE;
 303
 304        result = usb_control_msg(dev->usbdev, usb_sndctrlpipe(dev->usbdev, 0),
 305                SUR40_POKE, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 306                0x07, setting_07[value], NULL, 0, 1000);
 307        if (result < 0)
 308                goto error;
 309        msleep(5);
 310
 311        result = usb_control_msg(dev->usbdev, usb_sndctrlpipe(dev->usbdev, 0),
 312                SUR40_POKE, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 313                0x17, setting_17[value], NULL, 0, 1000);
 314        if (result < 0)
 315                goto error;
 316        msleep(5);
 317
 318error:
 319        return result;
 320}
 321
 322static void sur40_set_vsvideo(struct sur40_state *handle, u8 value)
 323{
 324        int i;
 325
 326        for (i = 0; i < 4; i++)
 327                sur40_poke(handle, 0x1c+i, value);
 328        handle->vsvideo = value;
 329}
 330
 331static void sur40_set_irlevel(struct sur40_state *handle, u8 value)
 332{
 333        int i;
 334
 335        for (i = 0; i < 8; i++)
 336                sur40_poke(handle, 0x08+(2*i), value);
 337}
 338
 339/* Initialization routine, called from sur40_open */
 340static int sur40_init(struct sur40_state *dev)
 341{
 342        int result;
 343        u8 *buffer;
 344
 345        buffer = kmalloc(24, GFP_KERNEL);
 346        if (!buffer) {
 347                result = -ENOMEM;
 348                goto error;
 349        }
 350
 351        /* stupidly replay the original MS driver init sequence */
 352        result = sur40_command(dev, SUR40_GET_VERSION, 0x00, buffer, 12);
 353        if (result < 0)
 354                goto error;
 355
 356        result = sur40_command(dev, SUR40_GET_VERSION, 0x01, buffer, 12);
 357        if (result < 0)
 358                goto error;
 359
 360        result = sur40_command(dev, SUR40_GET_VERSION, 0x02, buffer, 12);
 361        if (result < 0)
 362                goto error;
 363
 364        result = sur40_command(dev, SUR40_SENSOR_CAPS, 0x00, buffer, 24);
 365        if (result < 0)
 366                goto error;
 367
 368        result = sur40_command(dev, SUR40_ACCEL_CAPS, 0x00, buffer, 5);
 369        if (result < 0)
 370                goto error;
 371
 372        result = sur40_command(dev, SUR40_GET_VERSION, 0x03, buffer, 12);
 373        if (result < 0)
 374                goto error;
 375
 376        result = 0;
 377
 378        /*
 379         * Discard the result buffer - no known data inside except
 380         * some version strings, maybe extract these sometime...
 381         */
 382error:
 383        kfree(buffer);
 384        return result;
 385}
 386
 387/*
 388 * Callback routines from input_dev
 389 */
 390
 391/* Enable the device, polling will now start. */
 392static int sur40_open(struct input_dev *input)
 393{
 394        struct sur40_state *sur40 = input_get_drvdata(input);
 395
 396        dev_dbg(sur40->dev, "open\n");
 397        return sur40_init(sur40);
 398}
 399
 400/* Disable device, polling has stopped. */
 401static void sur40_close(struct input_dev *input)
 402{
 403        struct sur40_state *sur40 = input_get_drvdata(input);
 404
 405        dev_dbg(sur40->dev, "close\n");
 406        /*
 407         * There is no known way to stop the device, so we simply
 408         * stop polling.
 409         */
 410}
 411
 412/*
 413 * This function is called when a whole contact has been processed,
 414 * so that it can assign it to a slot and store the data there.
 415 */
 416static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input)
 417{
 418        int wide, major, minor;
 419        int bb_size_x, bb_size_y, pos_x, pos_y, ctr_x, ctr_y, slotnum;
 420
 421        if (blob->type != SUR40_TOUCH)
 422                return;
 423
 424        slotnum = input_mt_get_slot_by_key(input, blob->blob_id);
 425        if (slotnum < 0 || slotnum >= MAX_CONTACTS)
 426                return;
 427
 428        bb_size_x = le16_to_cpu(blob->bb_size_x);
 429        bb_size_y = le16_to_cpu(blob->bb_size_y);
 430
 431        pos_x = le16_to_cpu(blob->pos_x);
 432        pos_y = le16_to_cpu(blob->pos_y);
 433
 434        ctr_x = le16_to_cpu(blob->ctr_x);
 435        ctr_y = le16_to_cpu(blob->ctr_y);
 436
 437        input_mt_slot(input, slotnum);
 438        input_mt_report_slot_state(input, MT_TOOL_FINGER, 1);
 439        wide = (bb_size_x > bb_size_y);
 440        major = max(bb_size_x, bb_size_y);
 441        minor = min(bb_size_x, bb_size_y);
 442
 443        input_report_abs(input, ABS_MT_POSITION_X, pos_x);
 444        input_report_abs(input, ABS_MT_POSITION_Y, pos_y);
 445        input_report_abs(input, ABS_MT_TOOL_X, ctr_x);
 446        input_report_abs(input, ABS_MT_TOOL_Y, ctr_y);
 447
 448        /* TODO: use a better orientation measure */
 449        input_report_abs(input, ABS_MT_ORIENTATION, wide);
 450        input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
 451        input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
 452}
 453
 454/* core function: poll for new input data */
 455static void sur40_poll(struct input_dev *input)
 456{
 457        struct sur40_state *sur40 = input_get_drvdata(input);
 458        int result, bulk_read, need_blobs, packet_blobs, i;
 459        struct sur40_header *header = &sur40->bulk_in_buffer->header;
 460        struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0];
 461
 462        dev_dbg(sur40->dev, "poll\n");
 463
 464        need_blobs = -1;
 465
 466        do {
 467
 468                /* perform a blocking bulk read to get data from the device */
 469                result = usb_bulk_msg(sur40->usbdev,
 470                        usb_rcvbulkpipe(sur40->usbdev, sur40->bulk_in_epaddr),
 471                        sur40->bulk_in_buffer, sur40->bulk_in_size,
 472                        &bulk_read, 1000);
 473
 474                dev_dbg(sur40->dev, "received %d bytes\n", bulk_read);
 475
 476                if (result < 0) {
 477                        dev_err(sur40->dev, "error in usb_bulk_read\n");
 478                        return;
 479                }
 480
 481                result = bulk_read - sizeof(struct sur40_header);
 482
 483                if (result % sizeof(struct sur40_blob) != 0) {
 484                        dev_err(sur40->dev, "transfer size mismatch\n");
 485                        return;
 486                }
 487
 488                /* first packet? */
 489                if (need_blobs == -1) {
 490                        need_blobs = le16_to_cpu(header->count);
 491                        dev_dbg(sur40->dev, "need %d blobs\n", need_blobs);
 492                        /* packet_id = le32_to_cpu(header->packet_id); */
 493                }
 494
 495                /*
 496                 * Sanity check. when video data is also being retrieved, the
 497                 * packet ID will usually increase in the middle of a series
 498                 * instead of at the end. However, the data is still consistent,
 499                 * so the packet ID is probably just valid for the first packet
 500                 * in a series.
 501
 502                if (packet_id != le32_to_cpu(header->packet_id))
 503                        dev_dbg(sur40->dev, "packet ID mismatch\n");
 504                 */
 505
 506                packet_blobs = result / sizeof(struct sur40_blob);
 507                dev_dbg(sur40->dev, "received %d blobs\n", packet_blobs);
 508
 509                /* packets always contain at least 4 blobs, even if empty */
 510                if (packet_blobs > need_blobs)
 511                        packet_blobs = need_blobs;
 512
 513                for (i = 0; i < packet_blobs; i++) {
 514                        need_blobs--;
 515                        dev_dbg(sur40->dev, "processing blob\n");
 516                        sur40_report_blob(&(inblob[i]), input);
 517                }
 518
 519        } while (need_blobs > 0);
 520
 521        input_mt_sync_frame(input);
 522        input_sync(input);
 523
 524        sur40_process_video(sur40);
 525}
 526
 527/* deal with video data */
 528static void sur40_process_video(struct sur40_state *sur40)
 529{
 530
 531        struct sur40_image_header *img = (void *)(sur40->bulk_in_buffer);
 532        struct sur40_buffer *new_buf;
 533        struct usb_sg_request sgr;
 534        struct sg_table *sgt;
 535        int result, bulk_read;
 536
 537        if (!vb2_start_streaming_called(&sur40->queue))
 538                return;
 539
 540        /* get a new buffer from the list */
 541        spin_lock(&sur40->qlock);
 542        if (list_empty(&sur40->buf_list)) {
 543                dev_dbg(sur40->dev, "buffer queue empty\n");
 544                spin_unlock(&sur40->qlock);
 545                return;
 546        }
 547        new_buf = list_entry(sur40->buf_list.next, struct sur40_buffer, list);
 548        list_del(&new_buf->list);
 549        spin_unlock(&sur40->qlock);
 550
 551        dev_dbg(sur40->dev, "buffer acquired\n");
 552
 553        /* retrieve data via bulk read */
 554        result = usb_bulk_msg(sur40->usbdev,
 555                        usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT),
 556                        sur40->bulk_in_buffer, sur40->bulk_in_size,
 557                        &bulk_read, 1000);
 558
 559        if (result < 0) {
 560                dev_err(sur40->dev, "error in usb_bulk_read\n");
 561                goto err_poll;
 562        }
 563
 564        if (bulk_read != sizeof(struct sur40_image_header)) {
 565                dev_err(sur40->dev, "received %d bytes (%zd expected)\n",
 566                        bulk_read, sizeof(struct sur40_image_header));
 567                goto err_poll;
 568        }
 569
 570        if (le32_to_cpu(img->magic) != VIDEO_HEADER_MAGIC) {
 571                dev_err(sur40->dev, "image magic mismatch\n");
 572                goto err_poll;
 573        }
 574
 575        if (le32_to_cpu(img->size) != sur40->pix_fmt.sizeimage) {
 576                dev_err(sur40->dev, "image size mismatch\n");
 577                goto err_poll;
 578        }
 579
 580        dev_dbg(sur40->dev, "header acquired\n");
 581
 582        sgt = vb2_dma_sg_plane_desc(&new_buf->vb.vb2_buf, 0);
 583
 584        result = usb_sg_init(&sgr, sur40->usbdev,
 585                usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 0,
 586                sgt->sgl, sgt->nents, sur40->pix_fmt.sizeimage, 0);
 587        if (result < 0) {
 588                dev_err(sur40->dev, "error %d in usb_sg_init\n", result);
 589                goto err_poll;
 590        }
 591
 592        usb_sg_wait(&sgr);
 593        if (sgr.status < 0) {
 594                dev_err(sur40->dev, "error %d in usb_sg_wait\n", sgr.status);
 595                goto err_poll;
 596        }
 597
 598        dev_dbg(sur40->dev, "image acquired\n");
 599
 600        /* return error if streaming was stopped in the meantime */
 601        if (sur40->sequence == -1)
 602                return;
 603
 604        /* mark as finished */
 605        new_buf->vb.vb2_buf.timestamp = ktime_get_ns();
 606        new_buf->vb.sequence = sur40->sequence++;
 607        new_buf->vb.field = V4L2_FIELD_NONE;
 608        vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
 609        dev_dbg(sur40->dev, "buffer marked done\n");
 610        return;
 611
 612err_poll:
 613        vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
 614}
 615
 616/* Initialize input device parameters. */
 617static int sur40_input_setup_events(struct input_dev *input_dev)
 618{
 619        int error;
 620
 621        input_set_abs_params(input_dev, ABS_MT_POSITION_X,
 622                             0, SENSOR_RES_X, 0, 0);
 623        input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
 624                             0, SENSOR_RES_Y, 0, 0);
 625
 626        input_set_abs_params(input_dev, ABS_MT_TOOL_X,
 627                             0, SENSOR_RES_X, 0, 0);
 628        input_set_abs_params(input_dev, ABS_MT_TOOL_Y,
 629                             0, SENSOR_RES_Y, 0, 0);
 630
 631        /* max value unknown, but major/minor axis
 632         * can never be larger than screen */
 633        input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
 634                             0, SENSOR_RES_X, 0, 0);
 635        input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR,
 636                             0, SENSOR_RES_Y, 0, 0);
 637
 638        input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
 639
 640        error = input_mt_init_slots(input_dev, MAX_CONTACTS,
 641                                    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
 642        if (error) {
 643                dev_err(input_dev->dev.parent, "failed to set up slots\n");
 644                return error;
 645        }
 646
 647        return 0;
 648}
 649
 650/* Check candidate USB interface. */
 651static int sur40_probe(struct usb_interface *interface,
 652                       const struct usb_device_id *id)
 653{
 654        struct usb_device *usbdev = interface_to_usbdev(interface);
 655        struct sur40_state *sur40;
 656        struct usb_host_interface *iface_desc;
 657        struct usb_endpoint_descriptor *endpoint;
 658        struct input_dev *input;
 659        int error;
 660
 661        /* Check if we really have the right interface. */
 662        iface_desc = interface->cur_altsetting;
 663        if (iface_desc->desc.bInterfaceClass != 0xFF)
 664                return -ENODEV;
 665
 666        if (iface_desc->desc.bNumEndpoints < 5)
 667                return -ENODEV;
 668
 669        /* Use endpoint #4 (0x86). */
 670        endpoint = &iface_desc->endpoint[4].desc;
 671        if (endpoint->bEndpointAddress != TOUCH_ENDPOINT)
 672                return -ENODEV;
 673
 674        /* Allocate memory for our device state and initialize it. */
 675        sur40 = kzalloc(sizeof(struct sur40_state), GFP_KERNEL);
 676        if (!sur40)
 677                return -ENOMEM;
 678
 679        input = input_allocate_device();
 680        if (!input) {
 681                error = -ENOMEM;
 682                goto err_free_dev;
 683        }
 684
 685        /* initialize locks/lists */
 686        INIT_LIST_HEAD(&sur40->buf_list);
 687        spin_lock_init(&sur40->qlock);
 688        mutex_init(&sur40->lock);
 689
 690        /* Set up regular input device structure */
 691        input->name = DRIVER_LONG;
 692        usb_to_input_id(usbdev, &input->id);
 693        usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys));
 694        strlcat(sur40->phys, "/input0", sizeof(sur40->phys));
 695        input->phys = sur40->phys;
 696        input->dev.parent = &interface->dev;
 697
 698        input->open = sur40_open;
 699        input->close = sur40_close;
 700
 701        error = sur40_input_setup_events(input);
 702        if (error)
 703                goto err_free_input;
 704
 705        input_set_drvdata(input, sur40);
 706        error = input_setup_polling(input, sur40_poll);
 707        if (error) {
 708                dev_err(&interface->dev, "failed to set up polling");
 709                goto err_free_input;
 710        }
 711
 712        input_set_poll_interval(input, POLL_INTERVAL);
 713
 714        sur40->usbdev = usbdev;
 715        sur40->dev = &interface->dev;
 716        sur40->input = input;
 717
 718        /* use the bulk-in endpoint tested above */
 719        sur40->bulk_in_size = usb_endpoint_maxp(endpoint);
 720        sur40->bulk_in_epaddr = endpoint->bEndpointAddress;
 721        sur40->bulk_in_buffer = kmalloc(sur40->bulk_in_size, GFP_KERNEL);
 722        if (!sur40->bulk_in_buffer) {
 723                dev_err(&interface->dev, "Unable to allocate input buffer.");
 724                error = -ENOMEM;
 725                goto err_free_input;
 726        }
 727
 728        /* register the polled input device */
 729        error = input_register_device(input);
 730        if (error) {
 731                dev_err(&interface->dev,
 732                        "Unable to register polled input device.");
 733                goto err_free_buffer;
 734        }
 735
 736        /* register the video master device */
 737        snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG);
 738        error = v4l2_device_register(sur40->dev, &sur40->v4l2);
 739        if (error) {
 740                dev_err(&interface->dev,
 741                        "Unable to register video master device.");
 742                goto err_unreg_v4l2;
 743        }
 744
 745        /* initialize the lock and subdevice */
 746        sur40->queue = sur40_queue;
 747        sur40->queue.drv_priv = sur40;
 748        sur40->queue.lock = &sur40->lock;
 749        sur40->queue.dev = sur40->dev;
 750
 751        /* initialize the queue */
 752        error = vb2_queue_init(&sur40->queue);
 753        if (error)
 754                goto err_unreg_v4l2;
 755
 756        sur40->pix_fmt = sur40_pix_format[0];
 757        sur40->vdev = sur40_video_device;
 758        sur40->vdev.v4l2_dev = &sur40->v4l2;
 759        sur40->vdev.lock = &sur40->lock;
 760        sur40->vdev.queue = &sur40->queue;
 761        video_set_drvdata(&sur40->vdev, sur40);
 762
 763        /* initialize the control handler for 4 controls */
 764        v4l2_ctrl_handler_init(&sur40->hdl, 4);
 765        sur40->v4l2.ctrl_handler = &sur40->hdl;
 766        sur40->vsvideo = (SUR40_CONTRAST_DEF << 4) | SUR40_GAIN_DEF;
 767
 768        v4l2_ctrl_new_std(&sur40->hdl, &sur40_ctrl_ops, V4L2_CID_BRIGHTNESS,
 769          SUR40_BRIGHTNESS_MIN, SUR40_BRIGHTNESS_MAX, 1, clamp(brightness,
 770          (uint)SUR40_BRIGHTNESS_MIN, (uint)SUR40_BRIGHTNESS_MAX));
 771
 772        v4l2_ctrl_new_std(&sur40->hdl, &sur40_ctrl_ops, V4L2_CID_CONTRAST,
 773          SUR40_CONTRAST_MIN, SUR40_CONTRAST_MAX, 1, clamp(contrast,
 774          (uint)SUR40_CONTRAST_MIN, (uint)SUR40_CONTRAST_MAX));
 775
 776        v4l2_ctrl_new_std(&sur40->hdl, &sur40_ctrl_ops, V4L2_CID_GAIN,
 777          SUR40_GAIN_MIN, SUR40_GAIN_MAX, 1, clamp(gain,
 778          (uint)SUR40_GAIN_MIN, (uint)SUR40_GAIN_MAX));
 779
 780        v4l2_ctrl_new_std(&sur40->hdl, &sur40_ctrl_ops,
 781          V4L2_CID_BACKLIGHT_COMPENSATION, SUR40_BACKLIGHT_MIN,
 782          SUR40_BACKLIGHT_MAX, 1, SUR40_BACKLIGHT_DEF);
 783
 784        v4l2_ctrl_handler_setup(&sur40->hdl);
 785
 786        if (sur40->hdl.error) {
 787                dev_err(&interface->dev,
 788                        "Unable to register video controls.");
 789                v4l2_ctrl_handler_free(&sur40->hdl);
 790                goto err_unreg_v4l2;
 791        }
 792
 793        error = video_register_device(&sur40->vdev, VFL_TYPE_TOUCH, -1);
 794        if (error) {
 795                dev_err(&interface->dev,
 796                        "Unable to register video subdevice.");
 797                goto err_unreg_video;
 798        }
 799
 800        /* we can register the device now, as it is ready */
 801        usb_set_intfdata(interface, sur40);
 802        dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC);
 803
 804        return 0;
 805
 806err_unreg_video:
 807        video_unregister_device(&sur40->vdev);
 808err_unreg_v4l2:
 809        v4l2_device_unregister(&sur40->v4l2);
 810err_free_buffer:
 811        kfree(sur40->bulk_in_buffer);
 812err_free_input:
 813        input_free_device(input);
 814err_free_dev:
 815        kfree(sur40);
 816
 817        return error;
 818}
 819
 820/* Unregister device & clean up. */
 821static void sur40_disconnect(struct usb_interface *interface)
 822{
 823        struct sur40_state *sur40 = usb_get_intfdata(interface);
 824
 825        v4l2_ctrl_handler_free(&sur40->hdl);
 826        video_unregister_device(&sur40->vdev);
 827        v4l2_device_unregister(&sur40->v4l2);
 828
 829        input_unregister_device(sur40->input);
 830        kfree(sur40->bulk_in_buffer);
 831        kfree(sur40);
 832
 833        usb_set_intfdata(interface, NULL);
 834        dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC);
 835}
 836
 837/*
 838 * Setup the constraints of the queue: besides setting the number of planes
 839 * per buffer and the size and allocation context of each plane, it also
 840 * checks if sufficient buffers have been allocated. Usually 3 is a good
 841 * minimum number: many DMA engines need a minimum of 2 buffers in the
 842 * queue and you need to have another available for userspace processing.
 843 */
 844static int sur40_queue_setup(struct vb2_queue *q,
 845                       unsigned int *nbuffers, unsigned int *nplanes,
 846                       unsigned int sizes[], struct device *alloc_devs[])
 847{
 848        struct sur40_state *sur40 = vb2_get_drv_priv(q);
 849
 850        if (q->num_buffers + *nbuffers < 3)
 851                *nbuffers = 3 - q->num_buffers;
 852
 853        if (*nplanes)
 854                return sizes[0] < sur40->pix_fmt.sizeimage ? -EINVAL : 0;
 855
 856        *nplanes = 1;
 857        sizes[0] = sur40->pix_fmt.sizeimage;
 858
 859        return 0;
 860}
 861
 862/*
 863 * Prepare the buffer for queueing to the DMA engine: check and set the
 864 * payload size.
 865 */
 866static int sur40_buffer_prepare(struct vb2_buffer *vb)
 867{
 868        struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
 869        unsigned long size = sur40->pix_fmt.sizeimage;
 870
 871        if (vb2_plane_size(vb, 0) < size) {
 872                dev_err(&sur40->usbdev->dev, "buffer too small (%lu < %lu)\n",
 873                         vb2_plane_size(vb, 0), size);
 874                return -EINVAL;
 875        }
 876
 877        vb2_set_plane_payload(vb, 0, size);
 878        return 0;
 879}
 880
 881/*
 882 * Queue this buffer to the DMA engine.
 883 */
 884static void sur40_buffer_queue(struct vb2_buffer *vb)
 885{
 886        struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
 887        struct sur40_buffer *buf = (struct sur40_buffer *)vb;
 888
 889        spin_lock(&sur40->qlock);
 890        list_add_tail(&buf->list, &sur40->buf_list);
 891        spin_unlock(&sur40->qlock);
 892}
 893
 894static void return_all_buffers(struct sur40_state *sur40,
 895                               enum vb2_buffer_state state)
 896{
 897        struct sur40_buffer *buf, *node;
 898
 899        spin_lock(&sur40->qlock);
 900        list_for_each_entry_safe(buf, node, &sur40->buf_list, list) {
 901                vb2_buffer_done(&buf->vb.vb2_buf, state);
 902                list_del(&buf->list);
 903        }
 904        spin_unlock(&sur40->qlock);
 905}
 906
 907/*
 908 * Start streaming. First check if the minimum number of buffers have been
 909 * queued. If not, then return -ENOBUFS and the vb2 framework will call
 910 * this function again the next time a buffer has been queued until enough
 911 * buffers are available to actually start the DMA engine.
 912 */
 913static int sur40_start_streaming(struct vb2_queue *vq, unsigned int count)
 914{
 915        struct sur40_state *sur40 = vb2_get_drv_priv(vq);
 916
 917        sur40->sequence = 0;
 918        return 0;
 919}
 920
 921/*
 922 * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
 923 * and passed on to the vb2 framework marked as STATE_ERROR.
 924 */
 925static void sur40_stop_streaming(struct vb2_queue *vq)
 926{
 927        struct sur40_state *sur40 = vb2_get_drv_priv(vq);
 928        vb2_wait_for_all_buffers(vq);
 929        sur40->sequence = -1;
 930
 931        /* Release all active buffers */
 932        return_all_buffers(sur40, VB2_BUF_STATE_ERROR);
 933}
 934
 935/* V4L ioctl */
 936static int sur40_vidioc_querycap(struct file *file, void *priv,
 937                                 struct v4l2_capability *cap)
 938{
 939        struct sur40_state *sur40 = video_drvdata(file);
 940
 941        strlcpy(cap->driver, DRIVER_SHORT, sizeof(cap->driver));
 942        strlcpy(cap->card, DRIVER_LONG, sizeof(cap->card));
 943        usb_make_path(sur40->usbdev, cap->bus_info, sizeof(cap->bus_info));
 944        return 0;
 945}
 946
 947static int sur40_vidioc_enum_input(struct file *file, void *priv,
 948                                   struct v4l2_input *i)
 949{
 950        if (i->index != 0)
 951                return -EINVAL;
 952        i->type = V4L2_INPUT_TYPE_TOUCH;
 953        i->std = V4L2_STD_UNKNOWN;
 954        strlcpy(i->name, "In-Cell Sensor", sizeof(i->name));
 955        i->capabilities = 0;
 956        return 0;
 957}
 958
 959static int sur40_vidioc_s_input(struct file *file, void *priv, unsigned int i)
 960{
 961        return (i == 0) ? 0 : -EINVAL;
 962}
 963
 964static int sur40_vidioc_g_input(struct file *file, void *priv, unsigned int *i)
 965{
 966        *i = 0;
 967        return 0;
 968}
 969
 970static int sur40_vidioc_try_fmt(struct file *file, void *priv,
 971                            struct v4l2_format *f)
 972{
 973        switch (f->fmt.pix.pixelformat) {
 974        case V4L2_PIX_FMT_GREY:
 975                f->fmt.pix = sur40_pix_format[1];
 976                break;
 977
 978        default:
 979                f->fmt.pix = sur40_pix_format[0];
 980                break;
 981        }
 982
 983        return 0;
 984}
 985
 986static int sur40_vidioc_s_fmt(struct file *file, void *priv,
 987                            struct v4l2_format *f)
 988{
 989        struct sur40_state *sur40 = video_drvdata(file);
 990
 991        switch (f->fmt.pix.pixelformat) {
 992        case V4L2_PIX_FMT_GREY:
 993                sur40->pix_fmt = sur40_pix_format[1];
 994                break;
 995
 996        default:
 997                sur40->pix_fmt = sur40_pix_format[0];
 998                break;
 999        }
1000
1001        f->fmt.pix = sur40->pix_fmt;
1002        return 0;
1003}
1004
1005static int sur40_vidioc_g_fmt(struct file *file, void *priv,
1006                            struct v4l2_format *f)
1007{
1008        struct sur40_state *sur40 = video_drvdata(file);
1009
1010        f->fmt.pix = sur40->pix_fmt;
1011        return 0;
1012}
1013
1014static int sur40_s_ctrl(struct v4l2_ctrl *ctrl)
1015{
1016        struct sur40_state *sur40  = container_of(ctrl->handler,
1017          struct sur40_state, hdl);
1018        u8 value = sur40->vsvideo;
1019
1020        switch (ctrl->id) {
1021        case V4L2_CID_BRIGHTNESS:
1022                sur40_set_irlevel(sur40, ctrl->val);
1023                break;
1024        case V4L2_CID_CONTRAST:
1025                value = (value & 0x0f) | (ctrl->val << 4);
1026                sur40_set_vsvideo(sur40, value);
1027                break;
1028        case V4L2_CID_GAIN:
1029                value = (value & 0xf0) | (ctrl->val);
1030                sur40_set_vsvideo(sur40, value);
1031                break;
1032        case V4L2_CID_BACKLIGHT_COMPENSATION:
1033                sur40_set_preprocessor(sur40, ctrl->val);
1034                break;
1035        }
1036        return 0;
1037}
1038
1039static int sur40_ioctl_parm(struct file *file, void *priv,
1040                            struct v4l2_streamparm *p)
1041{
1042        if (p->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1043                return -EINVAL;
1044
1045        p->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
1046        p->parm.capture.timeperframe.numerator = 1;
1047        p->parm.capture.timeperframe.denominator = 60;
1048        p->parm.capture.readbuffers = 3;
1049        return 0;
1050}
1051
1052static int sur40_vidioc_enum_fmt(struct file *file, void *priv,
1053                                 struct v4l2_fmtdesc *f)
1054{
1055        if (f->index >= ARRAY_SIZE(sur40_pix_format))
1056                return -EINVAL;
1057
1058        f->pixelformat = sur40_pix_format[f->index].pixelformat;
1059        f->flags = 0;
1060        return 0;
1061}
1062
1063static int sur40_vidioc_enum_framesizes(struct file *file, void *priv,
1064                                        struct v4l2_frmsizeenum *f)
1065{
1066        struct sur40_state *sur40 = video_drvdata(file);
1067
1068        if ((f->index != 0) || ((f->pixel_format != V4L2_TCH_FMT_TU08)
1069                && (f->pixel_format != V4L2_PIX_FMT_GREY)))
1070                return -EINVAL;
1071
1072        f->type = V4L2_FRMSIZE_TYPE_DISCRETE;
1073        f->discrete.width  = sur40->pix_fmt.width;
1074        f->discrete.height = sur40->pix_fmt.height;
1075        return 0;
1076}
1077
1078static int sur40_vidioc_enum_frameintervals(struct file *file, void *priv,
1079                                            struct v4l2_frmivalenum *f)
1080{
1081        struct sur40_state *sur40 = video_drvdata(file);
1082
1083        if ((f->index > 0) || ((f->pixel_format != V4L2_TCH_FMT_TU08)
1084                && (f->pixel_format != V4L2_PIX_FMT_GREY))
1085                || (f->width  != sur40->pix_fmt.width)
1086                || (f->height != sur40->pix_fmt.height))
1087                return -EINVAL;
1088
1089        f->type = V4L2_FRMIVAL_TYPE_DISCRETE;
1090        f->discrete.denominator  = 60;
1091        f->discrete.numerator = 1;
1092        return 0;
1093}
1094
1095
1096static const struct usb_device_id sur40_table[] = {
1097        { USB_DEVICE(ID_MICROSOFT, ID_SUR40) },  /* Samsung SUR40 */
1098        { }                                      /* terminating null entry */
1099};
1100MODULE_DEVICE_TABLE(usb, sur40_table);
1101
1102/* V4L2 structures */
1103static const struct vb2_ops sur40_queue_ops = {
1104        .queue_setup            = sur40_queue_setup,
1105        .buf_prepare            = sur40_buffer_prepare,
1106        .buf_queue              = sur40_buffer_queue,
1107        .start_streaming        = sur40_start_streaming,
1108        .stop_streaming         = sur40_stop_streaming,
1109        .wait_prepare           = vb2_ops_wait_prepare,
1110        .wait_finish            = vb2_ops_wait_finish,
1111};
1112
1113static const struct vb2_queue sur40_queue = {
1114        .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
1115        /*
1116         * VB2_USERPTR in currently not enabled: passing a user pointer to
1117         * dma-sg will result in segment sizes that are not a multiple of
1118         * 512 bytes, which is required by the host controller.
1119        */
1120        .io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF,
1121        .buf_struct_size = sizeof(struct sur40_buffer),
1122        .ops = &sur40_queue_ops,
1123        .mem_ops = &vb2_dma_sg_memops,
1124        .timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC,
1125        .min_buffers_needed = 3,
1126};
1127
1128static const struct v4l2_file_operations sur40_video_fops = {
1129        .owner = THIS_MODULE,
1130        .open = v4l2_fh_open,
1131        .release = vb2_fop_release,
1132        .unlocked_ioctl = video_ioctl2,
1133        .read = vb2_fop_read,
1134        .mmap = vb2_fop_mmap,
1135        .poll = vb2_fop_poll,
1136};
1137
1138static const struct v4l2_ioctl_ops sur40_video_ioctl_ops = {
1139
1140        .vidioc_querycap        = sur40_vidioc_querycap,
1141
1142        .vidioc_enum_fmt_vid_cap = sur40_vidioc_enum_fmt,
1143        .vidioc_try_fmt_vid_cap = sur40_vidioc_try_fmt,
1144        .vidioc_s_fmt_vid_cap   = sur40_vidioc_s_fmt,
1145        .vidioc_g_fmt_vid_cap   = sur40_vidioc_g_fmt,
1146
1147        .vidioc_enum_framesizes = sur40_vidioc_enum_framesizes,
1148        .vidioc_enum_frameintervals = sur40_vidioc_enum_frameintervals,
1149
1150        .vidioc_g_parm = sur40_ioctl_parm,
1151        .vidioc_s_parm = sur40_ioctl_parm,
1152
1153        .vidioc_enum_input      = sur40_vidioc_enum_input,
1154        .vidioc_g_input         = sur40_vidioc_g_input,
1155        .vidioc_s_input         = sur40_vidioc_s_input,
1156
1157        .vidioc_reqbufs         = vb2_ioctl_reqbufs,
1158        .vidioc_create_bufs     = vb2_ioctl_create_bufs,
1159        .vidioc_querybuf        = vb2_ioctl_querybuf,
1160        .vidioc_qbuf            = vb2_ioctl_qbuf,
1161        .vidioc_dqbuf           = vb2_ioctl_dqbuf,
1162        .vidioc_expbuf          = vb2_ioctl_expbuf,
1163
1164        .vidioc_streamon        = vb2_ioctl_streamon,
1165        .vidioc_streamoff       = vb2_ioctl_streamoff,
1166};
1167
1168static const struct video_device sur40_video_device = {
1169        .name = DRIVER_LONG,
1170        .fops = &sur40_video_fops,
1171        .ioctl_ops = &sur40_video_ioctl_ops,
1172        .release = video_device_release_empty,
1173        .device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_TOUCH |
1174                       V4L2_CAP_READWRITE | V4L2_CAP_STREAMING,
1175};
1176
1177/* USB-specific object needed to register this driver with the USB subsystem. */
1178static struct usb_driver sur40_driver = {
1179        .name = DRIVER_SHORT,
1180        .probe = sur40_probe,
1181        .disconnect = sur40_disconnect,
1182        .id_table = sur40_table,
1183};
1184
1185module_usb_driver(sur40_driver);
1186
1187MODULE_AUTHOR(DRIVER_AUTHOR);
1188MODULE_DESCRIPTION(DRIVER_DESC);
1189MODULE_LICENSE("GPL");
1190