1 /* 2 * Surface2.0/SUR40/PixelSense input driver 3 * 4 * Copyright (c) 2013 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 * This program is free software; you can redistribute it and/or 16 * modify it under the terms of the GNU General Public License as 17 * published by the Free Software Foundation; either version 2 of 18 * the License, or (at your option) any later version. 19 */ 20 21 #include <linux/kernel.h> 22 #include <linux/errno.h> 23 #include <linux/delay.h> 24 #include <linux/init.h> 25 #include <linux/slab.h> 26 #include <linux/module.h> 27 #include <linux/completion.h> 28 #include <linux/uaccess.h> 29 #include <linux/usb.h> 30 #include <linux/printk.h> 31 #include <linux/input-polldev.h> 32 #include <linux/input/mt.h> 33 #include <linux/usb/input.h> 34 35 /* read 512 bytes from endpoint 0x86 -> get header + blobs */ 36 struct sur40_header { 37 38 __le16 type; /* always 0x0001 */ 39 __le16 count; /* count of blobs (if 0: continue prev. packet) */ 40 41 __le32 packet_id; /* unique ID for all packets in one frame */ 42 43 __le32 timestamp; /* milliseconds (inc. by 16 or 17 each frame) */ 44 __le32 unknown; /* "epoch?" always 02/03 00 00 00 */ 45 46 } __packed; 47 48 struct sur40_blob { 49 50 __le16 blob_id; 51 52 u8 action; /* 0x02 = enter/exit, 0x03 = update (?) */ 53 u8 unknown; /* always 0x01 or 0x02 (no idea what this is?) */ 54 55 __le16 bb_pos_x; /* upper left corner of bounding box */ 56 __le16 bb_pos_y; 57 58 __le16 bb_size_x; /* size of bounding box */ 59 __le16 bb_size_y; 60 61 __le16 pos_x; /* finger tip position */ 62 __le16 pos_y; 63 64 __le16 ctr_x; /* centroid position */ 65 __le16 ctr_y; 66 67 __le16 axis_x; /* somehow related to major/minor axis, mostly: */ 68 __le16 axis_y; /* axis_x == bb_size_y && axis_y == bb_size_x */ 69 70 __le32 angle; /* orientation in radians relative to x axis - 71 actually an IEEE754 float, don't use in kernel */ 72 73 __le32 area; /* size in pixels/pressure (?) */ 74 75 u8 padding[32]; 76 77 } __packed; 78 79 /* combined header/blob data */ 80 struct sur40_data { 81 struct sur40_header header; 82 struct sur40_blob blobs[]; 83 } __packed; 84 85 86 /* version information */ 87 #define DRIVER_SHORT "sur40" 88 #define DRIVER_AUTHOR "Florian 'floe' Echtler <floe@butterbrot.org>" 89 #define DRIVER_DESC "Surface2.0/SUR40/PixelSense input driver" 90 91 /* vendor and device IDs */ 92 #define ID_MICROSOFT 0x045e 93 #define ID_SUR40 0x0775 94 95 /* sensor resolution */ 96 #define SENSOR_RES_X 1920 97 #define SENSOR_RES_Y 1080 98 99 /* touch data endpoint */ 100 #define TOUCH_ENDPOINT 0x86 101 102 /* polling interval (ms) */ 103 #define POLL_INTERVAL 10 104 105 /* maximum number of contacts FIXME: this is a guess? */ 106 #define MAX_CONTACTS 64 107 108 /* control commands */ 109 #define SUR40_GET_VERSION 0xb0 /* 12 bytes string */ 110 #define SUR40_UNKNOWN1 0xb3 /* 5 bytes */ 111 #define SUR40_UNKNOWN2 0xc1 /* 24 bytes */ 112 113 #define SUR40_GET_STATE 0xc5 /* 4 bytes state (?) */ 114 #define SUR40_GET_SENSORS 0xb1 /* 8 bytes sensors */ 115 116 /* 117 * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT 118 * here by mistake which is very likely to have corrupted the firmware EEPROM 119 * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug. 120 * Should you ever run into a similar problem, the background story to this 121 * incident and instructions on how to fix the corrupted EEPROM are available 122 * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html 123 */ 124 125 struct sur40_state { 126 127 struct usb_device *usbdev; 128 struct device *dev; 129 struct input_polled_dev *input; 130 131 struct sur40_data *bulk_in_buffer; 132 size_t bulk_in_size; 133 u8 bulk_in_epaddr; 134 135 char phys[64]; 136 }; 137 138 static int sur40_command(struct sur40_state *dev, 139 u8 command, u16 index, void *buffer, u16 size) 140 { 141 return usb_control_msg(dev->usbdev, usb_rcvctrlpipe(dev->usbdev, 0), 142 command, 143 USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, 144 0x00, index, buffer, size, 1000); 145 } 146 147 /* Initialization routine, called from sur40_open */ 148 static int sur40_init(struct sur40_state *dev) 149 { 150 int result; 151 u8 buffer[24]; 152 153 /* stupidly replay the original MS driver init sequence */ 154 result = sur40_command(dev, SUR40_GET_VERSION, 0x00, buffer, 12); 155 if (result < 0) 156 return result; 157 158 result = sur40_command(dev, SUR40_GET_VERSION, 0x01, buffer, 12); 159 if (result < 0) 160 return result; 161 162 result = sur40_command(dev, SUR40_GET_VERSION, 0x02, buffer, 12); 163 if (result < 0) 164 return result; 165 166 result = sur40_command(dev, SUR40_UNKNOWN2, 0x00, buffer, 24); 167 if (result < 0) 168 return result; 169 170 result = sur40_command(dev, SUR40_UNKNOWN1, 0x00, buffer, 5); 171 if (result < 0) 172 return result; 173 174 result = sur40_command(dev, SUR40_GET_VERSION, 0x03, buffer, 12); 175 176 /* 177 * Discard the result buffer - no known data inside except 178 * some version strings, maybe extract these sometime... 179 */ 180 181 return result; 182 } 183 184 /* 185 * Callback routines from input_polled_dev 186 */ 187 188 /* Enable the device, polling will now start. */ 189 static void sur40_open(struct input_polled_dev *polldev) 190 { 191 struct sur40_state *sur40 = polldev->private; 192 193 dev_dbg(sur40->dev, "open\n"); 194 sur40_init(sur40); 195 } 196 197 /* Disable device, polling has stopped. */ 198 static void sur40_close(struct input_polled_dev *polldev) 199 { 200 struct sur40_state *sur40 = polldev->private; 201 202 dev_dbg(sur40->dev, "close\n"); 203 /* 204 * There is no known way to stop the device, so we simply 205 * stop polling. 206 */ 207 } 208 209 /* 210 * This function is called when a whole contact has been processed, 211 * so that it can assign it to a slot and store the data there. 212 */ 213 static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input) 214 { 215 int wide, major, minor; 216 217 int bb_size_x = le16_to_cpu(blob->bb_size_x); 218 int bb_size_y = le16_to_cpu(blob->bb_size_y); 219 220 int pos_x = le16_to_cpu(blob->pos_x); 221 int pos_y = le16_to_cpu(blob->pos_y); 222 223 int ctr_x = le16_to_cpu(blob->ctr_x); 224 int ctr_y = le16_to_cpu(blob->ctr_y); 225 226 int slotnum = input_mt_get_slot_by_key(input, blob->blob_id); 227 if (slotnum < 0 || slotnum >= MAX_CONTACTS) 228 return; 229 230 input_mt_slot(input, slotnum); 231 input_mt_report_slot_state(input, MT_TOOL_FINGER, 1); 232 wide = (bb_size_x > bb_size_y); 233 major = max(bb_size_x, bb_size_y); 234 minor = min(bb_size_x, bb_size_y); 235 236 input_report_abs(input, ABS_MT_POSITION_X, pos_x); 237 input_report_abs(input, ABS_MT_POSITION_Y, pos_y); 238 input_report_abs(input, ABS_MT_TOOL_X, ctr_x); 239 input_report_abs(input, ABS_MT_TOOL_Y, ctr_y); 240 241 /* TODO: use a better orientation measure */ 242 input_report_abs(input, ABS_MT_ORIENTATION, wide); 243 input_report_abs(input, ABS_MT_TOUCH_MAJOR, major); 244 input_report_abs(input, ABS_MT_TOUCH_MINOR, minor); 245 } 246 247 /* core function: poll for new input data */ 248 static void sur40_poll(struct input_polled_dev *polldev) 249 { 250 251 struct sur40_state *sur40 = polldev->private; 252 struct input_dev *input = polldev->input; 253 int result, bulk_read, need_blobs, packet_blobs, i; 254 u32 uninitialized_var(packet_id); 255 256 struct sur40_header *header = &sur40->bulk_in_buffer->header; 257 struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0]; 258 259 dev_dbg(sur40->dev, "poll\n"); 260 261 need_blobs = -1; 262 263 do { 264 265 /* perform a blocking bulk read to get data from the device */ 266 result = usb_bulk_msg(sur40->usbdev, 267 usb_rcvbulkpipe(sur40->usbdev, sur40->bulk_in_epaddr), 268 sur40->bulk_in_buffer, sur40->bulk_in_size, 269 &bulk_read, 1000); 270 271 dev_dbg(sur40->dev, "received %d bytes\n", bulk_read); 272 273 if (result < 0) { 274 dev_err(sur40->dev, "error in usb_bulk_read\n"); 275 return; 276 } 277 278 result = bulk_read - sizeof(struct sur40_header); 279 280 if (result % sizeof(struct sur40_blob) != 0) { 281 dev_err(sur40->dev, "transfer size mismatch\n"); 282 return; 283 } 284 285 /* first packet? */ 286 if (need_blobs == -1) { 287 need_blobs = le16_to_cpu(header->count); 288 dev_dbg(sur40->dev, "need %d blobs\n", need_blobs); 289 packet_id = le32_to_cpu(header->packet_id); 290 } 291 292 /* 293 * Sanity check. when video data is also being retrieved, the 294 * packet ID will usually increase in the middle of a series 295 * instead of at the end. 296 */ 297 if (packet_id != header->packet_id) 298 dev_warn(sur40->dev, "packet ID mismatch\n"); 299 300 packet_blobs = result / sizeof(struct sur40_blob); 301 dev_dbg(sur40->dev, "received %d blobs\n", packet_blobs); 302 303 /* packets always contain at least 4 blobs, even if empty */ 304 if (packet_blobs > need_blobs) 305 packet_blobs = need_blobs; 306 307 for (i = 0; i < packet_blobs; i++) { 308 need_blobs--; 309 dev_dbg(sur40->dev, "processing blob\n"); 310 sur40_report_blob(&(inblob[i]), input); 311 } 312 313 } while (need_blobs > 0); 314 315 input_mt_sync_frame(input); 316 input_sync(input); 317 } 318 319 /* Initialize input device parameters. */ 320 static void sur40_input_setup(struct input_dev *input_dev) 321 { 322 __set_bit(EV_KEY, input_dev->evbit); 323 __set_bit(EV_ABS, input_dev->evbit); 324 325 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 326 0, SENSOR_RES_X, 0, 0); 327 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 328 0, SENSOR_RES_Y, 0, 0); 329 330 input_set_abs_params(input_dev, ABS_MT_TOOL_X, 331 0, SENSOR_RES_X, 0, 0); 332 input_set_abs_params(input_dev, ABS_MT_TOOL_Y, 333 0, SENSOR_RES_Y, 0, 0); 334 335 /* max value unknown, but major/minor axis 336 * can never be larger than screen */ 337 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 338 0, SENSOR_RES_X, 0, 0); 339 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 340 0, SENSOR_RES_Y, 0, 0); 341 342 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0); 343 344 input_mt_init_slots(input_dev, MAX_CONTACTS, 345 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); 346 } 347 348 /* Check candidate USB interface. */ 349 static int sur40_probe(struct usb_interface *interface, 350 const struct usb_device_id *id) 351 { 352 struct usb_device *usbdev = interface_to_usbdev(interface); 353 struct sur40_state *sur40; 354 struct usb_host_interface *iface_desc; 355 struct usb_endpoint_descriptor *endpoint; 356 struct input_polled_dev *poll_dev; 357 int error; 358 359 /* Check if we really have the right interface. */ 360 iface_desc = &interface->altsetting[0]; 361 if (iface_desc->desc.bInterfaceClass != 0xFF) 362 return -ENODEV; 363 364 /* Use endpoint #4 (0x86). */ 365 endpoint = &iface_desc->endpoint[4].desc; 366 if (endpoint->bEndpointAddress != TOUCH_ENDPOINT) 367 return -ENODEV; 368 369 /* Allocate memory for our device state and initialize it. */ 370 sur40 = kzalloc(sizeof(struct sur40_state), GFP_KERNEL); 371 if (!sur40) 372 return -ENOMEM; 373 374 poll_dev = input_allocate_polled_device(); 375 if (!poll_dev) { 376 error = -ENOMEM; 377 goto err_free_dev; 378 } 379 380 /* Set up polled input device control structure */ 381 poll_dev->private = sur40; 382 poll_dev->poll_interval = POLL_INTERVAL; 383 poll_dev->open = sur40_open; 384 poll_dev->poll = sur40_poll; 385 poll_dev->close = sur40_close; 386 387 /* Set up regular input device structure */ 388 sur40_input_setup(poll_dev->input); 389 390 poll_dev->input->name = "Samsung SUR40"; 391 usb_to_input_id(usbdev, &poll_dev->input->id); 392 usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys)); 393 strlcat(sur40->phys, "/input0", sizeof(sur40->phys)); 394 poll_dev->input->phys = sur40->phys; 395 poll_dev->input->dev.parent = &interface->dev; 396 397 sur40->usbdev = usbdev; 398 sur40->dev = &interface->dev; 399 sur40->input = poll_dev; 400 401 /* use the bulk-in endpoint tested above */ 402 sur40->bulk_in_size = usb_endpoint_maxp(endpoint); 403 sur40->bulk_in_epaddr = endpoint->bEndpointAddress; 404 sur40->bulk_in_buffer = kmalloc(sur40->bulk_in_size, GFP_KERNEL); 405 if (!sur40->bulk_in_buffer) { 406 dev_err(&interface->dev, "Unable to allocate input buffer."); 407 error = -ENOMEM; 408 goto err_free_polldev; 409 } 410 411 error = input_register_polled_device(poll_dev); 412 if (error) { 413 dev_err(&interface->dev, 414 "Unable to register polled input device."); 415 goto err_free_buffer; 416 } 417 418 /* we can register the device now, as it is ready */ 419 usb_set_intfdata(interface, sur40); 420 dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC); 421 422 return 0; 423 424 err_free_buffer: 425 kfree(sur40->bulk_in_buffer); 426 err_free_polldev: 427 input_free_polled_device(sur40->input); 428 err_free_dev: 429 kfree(sur40); 430 431 return error; 432 } 433 434 /* Unregister device & clean up. */ 435 static void sur40_disconnect(struct usb_interface *interface) 436 { 437 struct sur40_state *sur40 = usb_get_intfdata(interface); 438 439 input_unregister_polled_device(sur40->input); 440 input_free_polled_device(sur40->input); 441 kfree(sur40->bulk_in_buffer); 442 kfree(sur40); 443 444 usb_set_intfdata(interface, NULL); 445 dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC); 446 } 447 448 static const struct usb_device_id sur40_table[] = { 449 { USB_DEVICE(ID_MICROSOFT, ID_SUR40) }, /* Samsung SUR40 */ 450 { } /* terminating null entry */ 451 }; 452 MODULE_DEVICE_TABLE(usb, sur40_table); 453 454 /* USB-specific object needed to register this driver with the USB subsystem. */ 455 static struct usb_driver sur40_driver = { 456 .name = DRIVER_SHORT, 457 .probe = sur40_probe, 458 .disconnect = sur40_disconnect, 459 .id_table = sur40_table, 460 }; 461 462 module_usb_driver(sur40_driver); 463 464 MODULE_AUTHOR(DRIVER_AUTHOR); 465 MODULE_DESCRIPTION(DRIVER_DESC); 466 MODULE_LICENSE("GPL"); 467