1 /*
2 * Surface2.0/SUR40/PixelSense input driver
3 *
4 * Copyright (c) 2014 by Florian 'floe' Echtler <floe@butterbrot.org>
5 *
6 * Derived from the USB Skeleton driver 1.1,
7 * Copyright (c) 2003 Greg Kroah-Hartman (greg@kroah.com)
8 *
9 * and from the Apple USB BCM5974 multitouch driver,
10 * Copyright (c) 2008 Henrik Rydberg (rydberg@euromail.se)
11 *
12 * and from the generic hid-multitouch driver,
13 * Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
14 *
15 * and from the v4l2-pci-skeleton driver,
16 * Copyright (c) Copyright 2014 Cisco Systems, Inc.
17 *
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License as
20 * published by the Free Software Foundation; either version 2 of
21 * the License, or (at your option) any later version.
22 */
23
24 #include <linux/kernel.h>
25 #include <linux/errno.h>
26 #include <linux/delay.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/module.h>
30 #include <linux/completion.h>
31 #include <linux/uaccess.h>
32 #include <linux/usb.h>
33 #include <linux/printk.h>
34 #include <linux/input-polldev.h>
35 #include <linux/input/mt.h>
36 #include <linux/usb/input.h>
37 #include <linux/videodev2.h>
38 #include <media/v4l2-device.h>
39 #include <media/v4l2-dev.h>
40 #include <media/v4l2-ioctl.h>
41 #include <media/videobuf2-v4l2.h>
42 #include <media/videobuf2-dma-sg.h>
43
44 /* read 512 bytes from endpoint 0x86 -> get header + blobs */
45 struct sur40_header {
46
47 __le16 type; /* always 0x0001 */
48 __le16 count; /* count of blobs (if 0: continue prev. packet) */
49
50 __le32 packet_id; /* unique ID for all packets in one frame */
51
52 __le32 timestamp; /* milliseconds (inc. by 16 or 17 each frame) */
53 __le32 unknown; /* "epoch?" always 02/03 00 00 00 */
54
55 } __packed;
56
57 struct sur40_blob {
58
59 __le16 blob_id;
60
61 u8 action; /* 0x02 = enter/exit, 0x03 = update (?) */
62 u8 unknown; /* always 0x01 or 0x02 (no idea what this is?) */
63
64 __le16 bb_pos_x; /* upper left corner of bounding box */
65 __le16 bb_pos_y;
66
67 __le16 bb_size_x; /* size of bounding box */
68 __le16 bb_size_y;
69
70 __le16 pos_x; /* finger tip position */
71 __le16 pos_y;
72
73 __le16 ctr_x; /* centroid position */
74 __le16 ctr_y;
75
76 __le16 axis_x; /* somehow related to major/minor axis, mostly: */
77 __le16 axis_y; /* axis_x == bb_size_y && axis_y == bb_size_x */
78
79 __le32 angle; /* orientation in radians relative to x axis -
80 actually an IEEE754 float, don't use in kernel */
81
82 __le32 area; /* size in pixels/pressure (?) */
83
84 u8 padding[32];
85
86 } __packed;
87
88 /* combined header/blob data */
89 struct sur40_data {
90 struct sur40_header header;
91 struct sur40_blob blobs[];
92 } __packed;
93
94 /* read 512 bytes from endpoint 0x82 -> get header below
95 * continue reading 16k blocks until header.size bytes read */
96 struct sur40_image_header {
97 __le32 magic; /* "SUBF" */
98 __le32 packet_id;
99 __le32 size; /* always 0x0007e900 = 960x540 */
100 __le32 timestamp; /* milliseconds (increases by 16 or 17 each frame) */
101 __le32 unknown; /* "epoch?" always 02/03 00 00 00 */
102 } __packed;
103
104 /* version information */
105 #define DRIVER_SHORT "sur40"
106 #define DRIVER_LONG "Samsung SUR40"
107 #define DRIVER_AUTHOR "Florian 'floe' Echtler <floe@butterbrot.org>"
108 #define DRIVER_DESC "Surface2.0/SUR40/PixelSense input driver"
109
110 /* vendor and device IDs */
111 #define ID_MICROSOFT 0x045e
112 #define ID_SUR40 0x0775
113
114 /* sensor resolution */
115 #define SENSOR_RES_X 1920
116 #define SENSOR_RES_Y 1080
117
118 /* touch data endpoint */
119 #define TOUCH_ENDPOINT 0x86
120
121 /* video data endpoint */
122 #define VIDEO_ENDPOINT 0x82
123
124 /* video header fields */
125 #define VIDEO_HEADER_MAGIC 0x46425553
126 #define VIDEO_PACKET_SIZE 16384
127
128 /* polling interval (ms) */
129 #define POLL_INTERVAL 1
130
131 /* maximum number of contacts FIXME: this is a guess? */
132 #define MAX_CONTACTS 64
133
134 /* control commands */
135 #define SUR40_GET_VERSION 0xb0 /* 12 bytes string */
136 #define SUR40_UNKNOWN1 0xb3 /* 5 bytes */
137 #define SUR40_UNKNOWN2 0xc1 /* 24 bytes */
138
139 #define SUR40_GET_STATE 0xc5 /* 4 bytes state (?) */
140 #define SUR40_GET_SENSORS 0xb1 /* 8 bytes sensors */
141
142 /* 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 */
sur40_command(struct sur40_state * dev,u8 command,u16 index,void * buffer,u16 size)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 */
sur40_init(struct sur40_state * dev)197 static int sur40_init(struct sur40_state *dev)
198 {
199 int result;
200 u8 buffer[24];
201
202 /* stupidly replay the original MS driver init sequence */
203 result = sur40_command(dev, SUR40_GET_VERSION, 0x00, buffer, 12);
204 if (result < 0)
205 return result;
206
207 result = sur40_command(dev, SUR40_GET_VERSION, 0x01, buffer, 12);
208 if (result < 0)
209 return result;
210
211 result = sur40_command(dev, SUR40_GET_VERSION, 0x02, buffer, 12);
212 if (result < 0)
213 return result;
214
215 result = sur40_command(dev, SUR40_UNKNOWN2, 0x00, buffer, 24);
216 if (result < 0)
217 return result;
218
219 result = sur40_command(dev, SUR40_UNKNOWN1, 0x00, buffer, 5);
220 if (result < 0)
221 return result;
222
223 result = sur40_command(dev, SUR40_GET_VERSION, 0x03, buffer, 12);
224
225 /*
226 * Discard the result buffer - no known data inside except
227 * some version strings, maybe extract these sometime...
228 */
229
230 return result;
231 }
232
233 /*
234 * Callback routines from input_polled_dev
235 */
236
237 /* Enable the device, polling will now start. */
sur40_open(struct input_polled_dev * polldev)238 static void sur40_open(struct input_polled_dev *polldev)
239 {
240 struct sur40_state *sur40 = polldev->private;
241
242 dev_dbg(sur40->dev, "open\n");
243 sur40_init(sur40);
244 }
245
246 /* Disable device, polling has stopped. */
sur40_close(struct input_polled_dev * polldev)247 static void sur40_close(struct input_polled_dev *polldev)
248 {
249 struct sur40_state *sur40 = polldev->private;
250
251 dev_dbg(sur40->dev, "close\n");
252 /*
253 * There is no known way to stop the device, so we simply
254 * stop polling.
255 */
256 }
257
258 /*
259 * This function is called when a whole contact has been processed,
260 * so that it can assign it to a slot and store the data there.
261 */
sur40_report_blob(struct sur40_blob * blob,struct input_dev * input)262 static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input)
263 {
264 int wide, major, minor;
265
266 int bb_size_x = le16_to_cpu(blob->bb_size_x);
267 int bb_size_y = le16_to_cpu(blob->bb_size_y);
268
269 int pos_x = le16_to_cpu(blob->pos_x);
270 int pos_y = le16_to_cpu(blob->pos_y);
271
272 int ctr_x = le16_to_cpu(blob->ctr_x);
273 int ctr_y = le16_to_cpu(blob->ctr_y);
274
275 int slotnum = input_mt_get_slot_by_key(input, blob->blob_id);
276 if (slotnum < 0 || slotnum >= MAX_CONTACTS)
277 return;
278
279 input_mt_slot(input, slotnum);
280 input_mt_report_slot_state(input, MT_TOOL_FINGER, 1);
281 wide = (bb_size_x > bb_size_y);
282 major = max(bb_size_x, bb_size_y);
283 minor = min(bb_size_x, bb_size_y);
284
285 input_report_abs(input, ABS_MT_POSITION_X, pos_x);
286 input_report_abs(input, ABS_MT_POSITION_Y, pos_y);
287 input_report_abs(input, ABS_MT_TOOL_X, ctr_x);
288 input_report_abs(input, ABS_MT_TOOL_Y, ctr_y);
289
290 /* TODO: use a better orientation measure */
291 input_report_abs(input, ABS_MT_ORIENTATION, wide);
292 input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
293 input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
294 }
295
296 /* core function: poll for new input data */
sur40_poll(struct input_polled_dev * polldev)297 static void sur40_poll(struct input_polled_dev *polldev)
298 {
299 struct sur40_state *sur40 = polldev->private;
300 struct input_dev *input = polldev->input;
301 int result, bulk_read, need_blobs, packet_blobs, i;
302 u32 uninitialized_var(packet_id);
303
304 struct sur40_header *header = &sur40->bulk_in_buffer->header;
305 struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0];
306
307 dev_dbg(sur40->dev, "poll\n");
308
309 need_blobs = -1;
310
311 do {
312
313 /* perform a blocking bulk read to get data from the device */
314 result = usb_bulk_msg(sur40->usbdev,
315 usb_rcvbulkpipe(sur40->usbdev, sur40->bulk_in_epaddr),
316 sur40->bulk_in_buffer, sur40->bulk_in_size,
317 &bulk_read, 1000);
318
319 dev_dbg(sur40->dev, "received %d bytes\n", bulk_read);
320
321 if (result < 0) {
322 dev_err(sur40->dev, "error in usb_bulk_read\n");
323 return;
324 }
325
326 result = bulk_read - sizeof(struct sur40_header);
327
328 if (result % sizeof(struct sur40_blob) != 0) {
329 dev_err(sur40->dev, "transfer size mismatch\n");
330 return;
331 }
332
333 /* first packet? */
334 if (need_blobs == -1) {
335 need_blobs = le16_to_cpu(header->count);
336 dev_dbg(sur40->dev, "need %d blobs\n", need_blobs);
337 packet_id = le32_to_cpu(header->packet_id);
338 }
339
340 /*
341 * Sanity check. when video data is also being retrieved, the
342 * packet ID will usually increase in the middle of a series
343 * instead of at the end.
344 */
345 if (packet_id != header->packet_id)
346 dev_dbg(sur40->dev, "packet ID mismatch\n");
347
348 packet_blobs = result / sizeof(struct sur40_blob);
349 dev_dbg(sur40->dev, "received %d blobs\n", packet_blobs);
350
351 /* packets always contain at least 4 blobs, even if empty */
352 if (packet_blobs > need_blobs)
353 packet_blobs = need_blobs;
354
355 for (i = 0; i < packet_blobs; i++) {
356 need_blobs--;
357 dev_dbg(sur40->dev, "processing blob\n");
358 sur40_report_blob(&(inblob[i]), input);
359 }
360
361 } while (need_blobs > 0);
362
363 input_mt_sync_frame(input);
364 input_sync(input);
365
366 sur40_process_video(sur40);
367 }
368
369 /* deal with video data */
sur40_process_video(struct sur40_state * sur40)370 static void sur40_process_video(struct sur40_state *sur40)
371 {
372
373 struct sur40_image_header *img = (void *)(sur40->bulk_in_buffer);
374 struct sur40_buffer *new_buf;
375 struct usb_sg_request sgr;
376 struct sg_table *sgt;
377 int result, bulk_read;
378
379 if (!vb2_start_streaming_called(&sur40->queue))
380 return;
381
382 /* get a new buffer from the list */
383 spin_lock(&sur40->qlock);
384 if (list_empty(&sur40->buf_list)) {
385 dev_dbg(sur40->dev, "buffer queue empty\n");
386 spin_unlock(&sur40->qlock);
387 return;
388 }
389 new_buf = list_entry(sur40->buf_list.next, struct sur40_buffer, list);
390 list_del(&new_buf->list);
391 spin_unlock(&sur40->qlock);
392
393 dev_dbg(sur40->dev, "buffer acquired\n");
394
395 /* retrieve data via bulk read */
396 result = usb_bulk_msg(sur40->usbdev,
397 usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT),
398 sur40->bulk_in_buffer, sur40->bulk_in_size,
399 &bulk_read, 1000);
400
401 if (result < 0) {
402 dev_err(sur40->dev, "error in usb_bulk_read\n");
403 goto err_poll;
404 }
405
406 if (bulk_read != sizeof(struct sur40_image_header)) {
407 dev_err(sur40->dev, "received %d bytes (%zd expected)\n",
408 bulk_read, sizeof(struct sur40_image_header));
409 goto err_poll;
410 }
411
412 if (le32_to_cpu(img->magic) != VIDEO_HEADER_MAGIC) {
413 dev_err(sur40->dev, "image magic mismatch\n");
414 goto err_poll;
415 }
416
417 if (le32_to_cpu(img->size) != sur40_video_format.sizeimage) {
418 dev_err(sur40->dev, "image size mismatch\n");
419 goto err_poll;
420 }
421
422 dev_dbg(sur40->dev, "header acquired\n");
423
424 sgt = vb2_dma_sg_plane_desc(&new_buf->vb.vb2_buf, 0);
425
426 result = usb_sg_init(&sgr, sur40->usbdev,
427 usb_rcvbulkpipe(sur40->usbdev, VIDEO_ENDPOINT), 0,
428 sgt->sgl, sgt->nents, sur40_video_format.sizeimage, 0);
429 if (result < 0) {
430 dev_err(sur40->dev, "error %d in usb_sg_init\n", result);
431 goto err_poll;
432 }
433
434 usb_sg_wait(&sgr);
435 if (sgr.status < 0) {
436 dev_err(sur40->dev, "error %d in usb_sg_wait\n", sgr.status);
437 goto err_poll;
438 }
439
440 dev_dbg(sur40->dev, "image acquired\n");
441
442 /* return error if streaming was stopped in the meantime */
443 if (sur40->sequence == -1)
444 return;
445
446 /* mark as finished */
447 v4l2_get_timestamp(&new_buf->vb.timestamp);
448 new_buf->vb.sequence = sur40->sequence++;
449 new_buf->vb.field = V4L2_FIELD_NONE;
450 vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
451 dev_dbg(sur40->dev, "buffer marked done\n");
452 return;
453
454 err_poll:
455 vb2_buffer_done(&new_buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
456 }
457
458 /* Initialize input device parameters. */
sur40_input_setup(struct input_dev * input_dev)459 static void sur40_input_setup(struct input_dev *input_dev)
460 {
461 __set_bit(EV_KEY, input_dev->evbit);
462 __set_bit(EV_ABS, input_dev->evbit);
463
464 input_set_abs_params(input_dev, ABS_MT_POSITION_X,
465 0, SENSOR_RES_X, 0, 0);
466 input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
467 0, SENSOR_RES_Y, 0, 0);
468
469 input_set_abs_params(input_dev, ABS_MT_TOOL_X,
470 0, SENSOR_RES_X, 0, 0);
471 input_set_abs_params(input_dev, ABS_MT_TOOL_Y,
472 0, SENSOR_RES_Y, 0, 0);
473
474 /* max value unknown, but major/minor axis
475 * can never be larger than screen */
476 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
477 0, SENSOR_RES_X, 0, 0);
478 input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR,
479 0, SENSOR_RES_Y, 0, 0);
480
481 input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
482
483 input_mt_init_slots(input_dev, MAX_CONTACTS,
484 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
485 }
486
487 /* Check candidate USB interface. */
sur40_probe(struct usb_interface * interface,const struct usb_device_id * id)488 static int sur40_probe(struct usb_interface *interface,
489 const struct usb_device_id *id)
490 {
491 struct usb_device *usbdev = interface_to_usbdev(interface);
492 struct sur40_state *sur40;
493 struct usb_host_interface *iface_desc;
494 struct usb_endpoint_descriptor *endpoint;
495 struct input_polled_dev *poll_dev;
496 int error;
497
498 /* Check if we really have the right interface. */
499 iface_desc = interface->cur_altsetting;
500 if (iface_desc->desc.bInterfaceClass != 0xFF)
501 return -ENODEV;
502
503 if (iface_desc->desc.bNumEndpoints < 5)
504 return -ENODEV;
505
506 /* Use endpoint #4 (0x86). */
507 endpoint = &iface_desc->endpoint[4].desc;
508 if (endpoint->bEndpointAddress != TOUCH_ENDPOINT)
509 return -ENODEV;
510
511 /* Allocate memory for our device state and initialize it. */
512 sur40 = kzalloc(sizeof(struct sur40_state), GFP_KERNEL);
513 if (!sur40)
514 return -ENOMEM;
515
516 poll_dev = input_allocate_polled_device();
517 if (!poll_dev) {
518 error = -ENOMEM;
519 goto err_free_dev;
520 }
521
522 /* initialize locks/lists */
523 INIT_LIST_HEAD(&sur40->buf_list);
524 spin_lock_init(&sur40->qlock);
525 mutex_init(&sur40->lock);
526
527 /* Set up polled input device control structure */
528 poll_dev->private = sur40;
529 poll_dev->poll_interval = POLL_INTERVAL;
530 poll_dev->open = sur40_open;
531 poll_dev->poll = sur40_poll;
532 poll_dev->close = sur40_close;
533
534 /* Set up regular input device structure */
535 sur40_input_setup(poll_dev->input);
536
537 poll_dev->input->name = DRIVER_LONG;
538 usb_to_input_id(usbdev, &poll_dev->input->id);
539 usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys));
540 strlcat(sur40->phys, "/input0", sizeof(sur40->phys));
541 poll_dev->input->phys = sur40->phys;
542 poll_dev->input->dev.parent = &interface->dev;
543
544 sur40->usbdev = usbdev;
545 sur40->dev = &interface->dev;
546 sur40->input = poll_dev;
547
548 /* use the bulk-in endpoint tested above */
549 sur40->bulk_in_size = usb_endpoint_maxp(endpoint);
550 sur40->bulk_in_epaddr = endpoint->bEndpointAddress;
551 sur40->bulk_in_buffer = kmalloc(sur40->bulk_in_size, GFP_KERNEL);
552 if (!sur40->bulk_in_buffer) {
553 dev_err(&interface->dev, "Unable to allocate input buffer.");
554 error = -ENOMEM;
555 goto err_free_polldev;
556 }
557
558 /* register the polled input device */
559 error = input_register_polled_device(poll_dev);
560 if (error) {
561 dev_err(&interface->dev,
562 "Unable to register polled input device.");
563 goto err_free_buffer;
564 }
565
566 /* register the video master device */
567 snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG);
568 error = v4l2_device_register(sur40->dev, &sur40->v4l2);
569 if (error) {
570 dev_err(&interface->dev,
571 "Unable to register video master device.");
572 goto err_unreg_v4l2;
573 }
574
575 /* initialize the lock and subdevice */
576 sur40->queue = sur40_queue;
577 sur40->queue.drv_priv = sur40;
578 sur40->queue.lock = &sur40->lock;
579
580 /* initialize the queue */
581 error = vb2_queue_init(&sur40->queue);
582 if (error)
583 goto err_unreg_v4l2;
584
585 sur40->alloc_ctx = vb2_dma_sg_init_ctx(sur40->dev);
586 if (IS_ERR(sur40->alloc_ctx)) {
587 dev_err(sur40->dev, "Can't allocate buffer context");
588 error = PTR_ERR(sur40->alloc_ctx);
589 goto err_unreg_v4l2;
590 }
591
592 sur40->vdev = sur40_video_device;
593 sur40->vdev.v4l2_dev = &sur40->v4l2;
594 sur40->vdev.lock = &sur40->lock;
595 sur40->vdev.queue = &sur40->queue;
596 video_set_drvdata(&sur40->vdev, sur40);
597
598 error = video_register_device(&sur40->vdev, VFL_TYPE_GRABBER, -1);
599 if (error) {
600 dev_err(&interface->dev,
601 "Unable to register video subdevice.");
602 goto err_unreg_video;
603 }
604
605 /* we can register the device now, as it is ready */
606 usb_set_intfdata(interface, sur40);
607 dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC);
608
609 return 0;
610
611 err_unreg_video:
612 video_unregister_device(&sur40->vdev);
613 err_unreg_v4l2:
614 v4l2_device_unregister(&sur40->v4l2);
615 err_free_buffer:
616 kfree(sur40->bulk_in_buffer);
617 err_free_polldev:
618 input_free_polled_device(sur40->input);
619 err_free_dev:
620 kfree(sur40);
621
622 return error;
623 }
624
625 /* Unregister device & clean up. */
sur40_disconnect(struct usb_interface * interface)626 static void sur40_disconnect(struct usb_interface *interface)
627 {
628 struct sur40_state *sur40 = usb_get_intfdata(interface);
629
630 video_unregister_device(&sur40->vdev);
631 v4l2_device_unregister(&sur40->v4l2);
632 vb2_dma_sg_cleanup_ctx(sur40->alloc_ctx);
633
634 input_unregister_polled_device(sur40->input);
635 input_free_polled_device(sur40->input);
636 kfree(sur40->bulk_in_buffer);
637 kfree(sur40);
638
639 usb_set_intfdata(interface, NULL);
640 dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC);
641 }
642
643 /*
644 * Setup the constraints of the queue: besides setting the number of planes
645 * per buffer and the size and allocation context of each plane, it also
646 * checks if sufficient buffers have been allocated. Usually 3 is a good
647 * minimum number: many DMA engines need a minimum of 2 buffers in the
648 * queue and you need to have another available for userspace processing.
649 */
sur40_queue_setup(struct vb2_queue * q,const void * parg,unsigned int * nbuffers,unsigned int * nplanes,unsigned int sizes[],void * alloc_ctxs[])650 static int sur40_queue_setup(struct vb2_queue *q, const void *parg,
651 unsigned int *nbuffers, unsigned int *nplanes,
652 unsigned int sizes[], void *alloc_ctxs[])
653 {
654 const struct v4l2_format *fmt = parg;
655 struct sur40_state *sur40 = vb2_get_drv_priv(q);
656
657 if (q->num_buffers + *nbuffers < 3)
658 *nbuffers = 3 - q->num_buffers;
659
660 if (fmt && fmt->fmt.pix.sizeimage < sur40_video_format.sizeimage)
661 return -EINVAL;
662
663 *nplanes = 1;
664 sizes[0] = fmt ? fmt->fmt.pix.sizeimage : sur40_video_format.sizeimage;
665 alloc_ctxs[0] = sur40->alloc_ctx;
666
667 return 0;
668 }
669
670 /*
671 * Prepare the buffer for queueing to the DMA engine: check and set the
672 * payload size.
673 */
sur40_buffer_prepare(struct vb2_buffer * vb)674 static int sur40_buffer_prepare(struct vb2_buffer *vb)
675 {
676 struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
677 unsigned long size = sur40_video_format.sizeimage;
678
679 if (vb2_plane_size(vb, 0) < size) {
680 dev_err(&sur40->usbdev->dev, "buffer too small (%lu < %lu)\n",
681 vb2_plane_size(vb, 0), size);
682 return -EINVAL;
683 }
684
685 vb2_set_plane_payload(vb, 0, size);
686 return 0;
687 }
688
689 /*
690 * Queue this buffer to the DMA engine.
691 */
sur40_buffer_queue(struct vb2_buffer * vb)692 static void sur40_buffer_queue(struct vb2_buffer *vb)
693 {
694 struct sur40_state *sur40 = vb2_get_drv_priv(vb->vb2_queue);
695 struct sur40_buffer *buf = (struct sur40_buffer *)vb;
696
697 spin_lock(&sur40->qlock);
698 list_add_tail(&buf->list, &sur40->buf_list);
699 spin_unlock(&sur40->qlock);
700 }
701
return_all_buffers(struct sur40_state * sur40,enum vb2_buffer_state state)702 static void return_all_buffers(struct sur40_state *sur40,
703 enum vb2_buffer_state state)
704 {
705 struct sur40_buffer *buf, *node;
706
707 spin_lock(&sur40->qlock);
708 list_for_each_entry_safe(buf, node, &sur40->buf_list, list) {
709 vb2_buffer_done(&buf->vb.vb2_buf, state);
710 list_del(&buf->list);
711 }
712 spin_unlock(&sur40->qlock);
713 }
714
715 /*
716 * Start streaming. First check if the minimum number of buffers have been
717 * queued. If not, then return -ENOBUFS and the vb2 framework will call
718 * this function again the next time a buffer has been queued until enough
719 * buffers are available to actually start the DMA engine.
720 */
sur40_start_streaming(struct vb2_queue * vq,unsigned int count)721 static int sur40_start_streaming(struct vb2_queue *vq, unsigned int count)
722 {
723 struct sur40_state *sur40 = vb2_get_drv_priv(vq);
724
725 sur40->sequence = 0;
726 return 0;
727 }
728
729 /*
730 * Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
731 * and passed on to the vb2 framework marked as STATE_ERROR.
732 */
sur40_stop_streaming(struct vb2_queue * vq)733 static void sur40_stop_streaming(struct vb2_queue *vq)
734 {
735 struct sur40_state *sur40 = vb2_get_drv_priv(vq);
736 vb2_wait_for_all_buffers(vq);
737 sur40->sequence = -1;
738
739 /* Release all active buffers */
740 return_all_buffers(sur40, VB2_BUF_STATE_ERROR);
741 }
742
743 /* V4L ioctl */
sur40_vidioc_querycap(struct file * file,void * priv,struct v4l2_capability * cap)744 static int sur40_vidioc_querycap(struct file *file, void *priv,
745 struct v4l2_capability *cap)
746 {
747 struct sur40_state *sur40 = video_drvdata(file);
748
749 strlcpy(cap->driver, DRIVER_SHORT, sizeof(cap->driver));
750 strlcpy(cap->card, DRIVER_LONG, sizeof(cap->card));
751 usb_make_path(sur40->usbdev, cap->bus_info, sizeof(cap->bus_info));
752 cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
753 V4L2_CAP_READWRITE |
754 V4L2_CAP_STREAMING;
755 cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
756 return 0;
757 }
758
sur40_vidioc_enum_input(struct file * file,void * priv,struct v4l2_input * i)759 static int sur40_vidioc_enum_input(struct file *file, void *priv,
760 struct v4l2_input *i)
761 {
762 if (i->index != 0)
763 return -EINVAL;
764 i->type = V4L2_INPUT_TYPE_CAMERA;
765 i->std = V4L2_STD_UNKNOWN;
766 strlcpy(i->name, "In-Cell Sensor", sizeof(i->name));
767 i->capabilities = 0;
768 return 0;
769 }
770
sur40_vidioc_s_input(struct file * file,void * priv,unsigned int i)771 static int sur40_vidioc_s_input(struct file *file, void *priv, unsigned int i)
772 {
773 return (i == 0) ? 0 : -EINVAL;
774 }
775
sur40_vidioc_g_input(struct file * file,void * priv,unsigned int * i)776 static int sur40_vidioc_g_input(struct file *file, void *priv, unsigned int *i)
777 {
778 *i = 0;
779 return 0;
780 }
781
sur40_vidioc_fmt(struct file * file,void * priv,struct v4l2_format * f)782 static int sur40_vidioc_fmt(struct file *file, void *priv,
783 struct v4l2_format *f)
784 {
785 f->fmt.pix = sur40_video_format;
786 return 0;
787 }
788
sur40_vidioc_enum_fmt(struct file * file,void * priv,struct v4l2_fmtdesc * f)789 static int sur40_vidioc_enum_fmt(struct file *file, void *priv,
790 struct v4l2_fmtdesc *f)
791 {
792 if (f->index != 0)
793 return -EINVAL;
794 strlcpy(f->description, "8-bit greyscale", sizeof(f->description));
795 f->pixelformat = V4L2_PIX_FMT_GREY;
796 f->flags = 0;
797 return 0;
798 }
799
sur40_vidioc_enum_framesizes(struct file * file,void * priv,struct v4l2_frmsizeenum * f)800 static int sur40_vidioc_enum_framesizes(struct file *file, void *priv,
801 struct v4l2_frmsizeenum *f)
802 {
803 if ((f->index != 0) || (f->pixel_format != V4L2_PIX_FMT_GREY))
804 return -EINVAL;
805
806 f->type = V4L2_FRMSIZE_TYPE_DISCRETE;
807 f->discrete.width = sur40_video_format.width;
808 f->discrete.height = sur40_video_format.height;
809 return 0;
810 }
811
sur40_vidioc_enum_frameintervals(struct file * file,void * priv,struct v4l2_frmivalenum * f)812 static int sur40_vidioc_enum_frameintervals(struct file *file, void *priv,
813 struct v4l2_frmivalenum *f)
814 {
815 if ((f->index > 1) || (f->pixel_format != V4L2_PIX_FMT_GREY)
816 || (f->width != sur40_video_format.width)
817 || (f->height != sur40_video_format.height))
818 return -EINVAL;
819
820 f->type = V4L2_FRMIVAL_TYPE_DISCRETE;
821 f->discrete.denominator = 60/(f->index+1);
822 f->discrete.numerator = 1;
823 return 0;
824 }
825
826
827 static const struct usb_device_id sur40_table[] = {
828 { USB_DEVICE(ID_MICROSOFT, ID_SUR40) }, /* Samsung SUR40 */
829 { } /* terminating null entry */
830 };
831 MODULE_DEVICE_TABLE(usb, sur40_table);
832
833 /* V4L2 structures */
834 static const struct vb2_ops sur40_queue_ops = {
835 .queue_setup = sur40_queue_setup,
836 .buf_prepare = sur40_buffer_prepare,
837 .buf_queue = sur40_buffer_queue,
838 .start_streaming = sur40_start_streaming,
839 .stop_streaming = sur40_stop_streaming,
840 .wait_prepare = vb2_ops_wait_prepare,
841 .wait_finish = vb2_ops_wait_finish,
842 };
843
844 static const struct vb2_queue sur40_queue = {
845 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
846 /*
847 * VB2_USERPTR in currently not enabled: passing a user pointer to
848 * dma-sg will result in segment sizes that are not a multiple of
849 * 512 bytes, which is required by the host controller.
850 */
851 .io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF,
852 .buf_struct_size = sizeof(struct sur40_buffer),
853 .ops = &sur40_queue_ops,
854 .mem_ops = &vb2_dma_sg_memops,
855 .timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC,
856 .min_buffers_needed = 3,
857 };
858
859 static const struct v4l2_file_operations sur40_video_fops = {
860 .owner = THIS_MODULE,
861 .open = v4l2_fh_open,
862 .release = vb2_fop_release,
863 .unlocked_ioctl = video_ioctl2,
864 .read = vb2_fop_read,
865 .mmap = vb2_fop_mmap,
866 .poll = vb2_fop_poll,
867 };
868
869 static const struct v4l2_ioctl_ops sur40_video_ioctl_ops = {
870
871 .vidioc_querycap = sur40_vidioc_querycap,
872
873 .vidioc_enum_fmt_vid_cap = sur40_vidioc_enum_fmt,
874 .vidioc_try_fmt_vid_cap = sur40_vidioc_fmt,
875 .vidioc_s_fmt_vid_cap = sur40_vidioc_fmt,
876 .vidioc_g_fmt_vid_cap = sur40_vidioc_fmt,
877
878 .vidioc_enum_framesizes = sur40_vidioc_enum_framesizes,
879 .vidioc_enum_frameintervals = sur40_vidioc_enum_frameintervals,
880
881 .vidioc_enum_input = sur40_vidioc_enum_input,
882 .vidioc_g_input = sur40_vidioc_g_input,
883 .vidioc_s_input = sur40_vidioc_s_input,
884
885 .vidioc_reqbufs = vb2_ioctl_reqbufs,
886 .vidioc_create_bufs = vb2_ioctl_create_bufs,
887 .vidioc_querybuf = vb2_ioctl_querybuf,
888 .vidioc_qbuf = vb2_ioctl_qbuf,
889 .vidioc_dqbuf = vb2_ioctl_dqbuf,
890 .vidioc_expbuf = vb2_ioctl_expbuf,
891
892 .vidioc_streamon = vb2_ioctl_streamon,
893 .vidioc_streamoff = vb2_ioctl_streamoff,
894 };
895
896 static const struct video_device sur40_video_device = {
897 .name = DRIVER_LONG,
898 .fops = &sur40_video_fops,
899 .ioctl_ops = &sur40_video_ioctl_ops,
900 .release = video_device_release_empty,
901 };
902
903 static const struct v4l2_pix_format sur40_video_format = {
904 .pixelformat = V4L2_PIX_FMT_GREY,
905 .width = SENSOR_RES_X / 2,
906 .height = SENSOR_RES_Y / 2,
907 .field = V4L2_FIELD_NONE,
908 .colorspace = V4L2_COLORSPACE_SRGB,
909 .bytesperline = SENSOR_RES_X / 2,
910 .sizeimage = (SENSOR_RES_X/2) * (SENSOR_RES_Y/2),
911 };
912
913 /* USB-specific object needed to register this driver with the USB subsystem. */
914 static struct usb_driver sur40_driver = {
915 .name = DRIVER_SHORT,
916 .probe = sur40_probe,
917 .disconnect = sur40_disconnect,
918 .id_table = sur40_table,
919 };
920
921 module_usb_driver(sur40_driver);
922
923 MODULE_AUTHOR(DRIVER_AUTHOR);
924 MODULE_DESCRIPTION(DRIVER_DESC);
925 MODULE_LICENSE("GPL");
926