xref: /linux/drivers/gpu/drm/tiny/appletbdrm.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Apple Touch Bar DRM Driver
4  *
5  * Copyright (c) 2023 Kerem Karabay <kekrby@gmail.com>
6  */
7 
8 #include <linux/align.h>
9 #include <linux/array_size.h>
10 #include <linux/bitops.h>
11 #include <linux/bug.h>
12 #include <linux/container_of.h>
13 #include <linux/err.h>
14 #include <linux/module.h>
15 #include <linux/overflow.h>
16 #include <linux/slab.h>
17 #include <linux/types.h>
18 #include <linux/unaligned.h>
19 #include <linux/usb.h>
20 
21 #include <drm/drm_atomic.h>
22 #include <drm/drm_atomic_helper.h>
23 #include <drm/drm_crtc.h>
24 #include <drm/drm_damage_helper.h>
25 #include <drm/drm_drv.h>
26 #include <drm/drm_encoder.h>
27 #include <drm/drm_format_helper.h>
28 #include <drm/drm_fourcc.h>
29 #include <drm/drm_framebuffer.h>
30 #include <drm/drm_gem_atomic_helper.h>
31 #include <drm/drm_gem_framebuffer_helper.h>
32 #include <drm/drm_gem_shmem_helper.h>
33 #include <drm/drm_plane.h>
34 #include <drm/drm_print.h>
35 #include <drm/drm_probe_helper.h>
36 
37 #define APPLETBDRM_PIXEL_FORMAT		cpu_to_le32(0x52474241) /* RGBA, the actual format is BGR888 */
38 #define APPLETBDRM_BITS_PER_PIXEL	24
39 
40 #define APPLETBDRM_MSG_CLEAR_DISPLAY	cpu_to_le32(0x434c5244) /* CLRD */
41 #define APPLETBDRM_MSG_GET_INFORMATION	cpu_to_le32(0x47494e46) /* GINF */
42 #define APPLETBDRM_MSG_UPDATE_COMPLETE	cpu_to_le32(0x5544434c) /* UDCL */
43 #define APPLETBDRM_MSG_SIGNAL_READINESS	cpu_to_le32(0x52454459) /* REDY */
44 
45 #define APPLETBDRM_BULK_MSG_TIMEOUT	1000
46 
47 #define drm_to_adev(_drm)		container_of(_drm, struct appletbdrm_device, drm)
48 #define adev_to_udev(adev)		interface_to_usbdev(to_usb_interface((adev)->drm.dev))
49 
50 struct appletbdrm_msg_request_header {
51 	__le16 unk_00;
52 	__le16 unk_02;
53 	__le32 unk_04;
54 	__le32 unk_08;
55 	__le32 size;
56 } __packed;
57 
58 struct appletbdrm_msg_response_header {
59 	u8 unk_00[16];
60 	__le32 msg;
61 } __packed;
62 
63 struct appletbdrm_msg_simple_request {
64 	struct appletbdrm_msg_request_header header;
65 	__le32 msg;
66 	u8 unk_14[8];
67 	__le32 size;
68 } __packed;
69 
70 struct appletbdrm_msg_information {
71 	struct appletbdrm_msg_response_header header;
72 	u8 unk_14[12];
73 	__le32 width;
74 	__le32 height;
75 	u8 bits_per_pixel;
76 	__le32 bytes_per_row;
77 	__le32 orientation;
78 	__le32 bitmap_info;
79 	__le32 pixel_format;
80 	__le32 width_inches;	/* floating point */
81 	__le32 height_inches;	/* floating point */
82 } __packed;
83 
84 struct appletbdrm_frame {
85 	__le16 begin_x;
86 	__le16 begin_y;
87 	__le16 width;
88 	__le16 height;
89 	__le32 buf_size;
90 	u8 buf[];
91 } __packed;
92 
93 struct appletbdrm_fb_request_footer {
94 	u8 unk_00[12];
95 	__le32 unk_0c;
96 	u8 unk_10[12];
97 	__le32 unk_1c;
98 	__le64 timestamp;
99 	u8 unk_28[12];
100 	__le32 unk_34;
101 	u8 unk_38[20];
102 	__le32 unk_4c;
103 } __packed;
104 
105 struct appletbdrm_fb_request {
106 	struct appletbdrm_msg_request_header header;
107 	__le16 unk_10;
108 	u8 msg_id;
109 	u8 unk_13[29];
110 	/*
111 	 * Contents of `data`:
112 	 * - struct appletbdrm_frame frames[];
113 	 * - struct appletbdrm_fb_request_footer footer;
114 	 * - padding to make the total size a multiple of 16
115 	 */
116 	u8 data[];
117 } __packed;
118 
119 struct appletbdrm_fb_request_response {
120 	struct appletbdrm_msg_response_header header;
121 	u8 unk_14[12];
122 	__le64 timestamp;
123 } __packed;
124 
125 struct appletbdrm_device {
126 	unsigned int in_ep;
127 	unsigned int out_ep;
128 
129 	unsigned int width;
130 	unsigned int height;
131 
132 	struct drm_device drm;
133 	struct drm_display_mode mode;
134 	struct drm_connector connector;
135 	struct drm_plane primary_plane;
136 	struct drm_crtc crtc;
137 	struct drm_encoder encoder;
138 };
139 
140 struct appletbdrm_plane_state {
141 	struct drm_shadow_plane_state base;
142 	struct appletbdrm_fb_request *request;
143 	struct appletbdrm_fb_request_response *response;
144 	size_t request_size;
145 	size_t frames_size;
146 };
147 
148 static inline struct appletbdrm_plane_state *to_appletbdrm_plane_state(struct drm_plane_state *state)
149 {
150 	return container_of(state, struct appletbdrm_plane_state, base.base);
151 }
152 
153 static int appletbdrm_send_request(struct appletbdrm_device *adev,
154 				   struct appletbdrm_msg_request_header *request, size_t size)
155 {
156 	struct usb_device *udev = adev_to_udev(adev);
157 	struct drm_device *drm = &adev->drm;
158 	int ret, actual_size;
159 
160 	ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, adev->out_ep),
161 			   request, size, &actual_size, APPLETBDRM_BULK_MSG_TIMEOUT);
162 	if (ret) {
163 		drm_err(drm, "Failed to send message (%d)\n", ret);
164 		return ret;
165 	}
166 
167 	if (actual_size != size) {
168 		drm_err(drm, "Actual size (%d) doesn't match expected size (%zu)\n",
169 			actual_size, size);
170 		return -EIO;
171 	}
172 
173 	return 0;
174 }
175 
176 static int appletbdrm_read_response(struct appletbdrm_device *adev,
177 				    struct appletbdrm_msg_response_header *response,
178 				    size_t size, __le32 expected_response)
179 {
180 	struct usb_device *udev = adev_to_udev(adev);
181 	struct drm_device *drm = &adev->drm;
182 	int ret, actual_size;
183 	bool readiness_signal_received = false;
184 
185 retry:
186 	ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, adev->in_ep),
187 			   response, size, &actual_size, APPLETBDRM_BULK_MSG_TIMEOUT);
188 	if (ret) {
189 		drm_err(drm, "Failed to read response (%d)\n", ret);
190 		return ret;
191 	}
192 
193 	/*
194 	 * The device responds to the first request sent in a particular
195 	 * timeframe after the USB device configuration is set with a readiness
196 	 * signal, in which case the response should be read again
197 	 */
198 	if (response->msg == APPLETBDRM_MSG_SIGNAL_READINESS) {
199 		if (!readiness_signal_received) {
200 			readiness_signal_received = true;
201 			goto retry;
202 		}
203 
204 		drm_err(drm, "Encountered unexpected readiness signal\n");
205 		return -EINTR;
206 	}
207 
208 	if (actual_size != size) {
209 		drm_err(drm, "Actual size (%d) doesn't match expected size (%zu)\n",
210 			actual_size, size);
211 		return -EBADMSG;
212 	}
213 
214 	if (response->msg != expected_response) {
215 		drm_err(drm, "Unexpected response from device (expected %p4cl found %p4cl)\n",
216 			&expected_response, &response->msg);
217 		return -EIO;
218 	}
219 
220 	return 0;
221 }
222 
223 static int appletbdrm_send_msg(struct appletbdrm_device *adev, __le32 msg)
224 {
225 	struct appletbdrm_msg_simple_request *request;
226 	int ret;
227 
228 	request = kzalloc_obj(*request, GFP_KERNEL);
229 	if (!request)
230 		return -ENOMEM;
231 
232 	request->header.unk_00 = cpu_to_le16(2);
233 	request->header.unk_02 = cpu_to_le16(0x1512);
234 	request->header.size = cpu_to_le32(sizeof(*request) - sizeof(request->header));
235 	request->msg = msg;
236 	request->size = request->header.size;
237 
238 	ret = appletbdrm_send_request(adev, &request->header, sizeof(*request));
239 
240 	kfree(request);
241 
242 	return ret;
243 }
244 
245 static int appletbdrm_clear_display(struct appletbdrm_device *adev)
246 {
247 	return appletbdrm_send_msg(adev, APPLETBDRM_MSG_CLEAR_DISPLAY);
248 }
249 
250 static int appletbdrm_signal_readiness(struct appletbdrm_device *adev)
251 {
252 	return appletbdrm_send_msg(adev, APPLETBDRM_MSG_SIGNAL_READINESS);
253 }
254 
255 static int appletbdrm_get_information(struct appletbdrm_device *adev)
256 {
257 	struct appletbdrm_msg_information *info;
258 	struct drm_device *drm = &adev->drm;
259 	u8 bits_per_pixel;
260 	__le32 pixel_format;
261 	int ret;
262 
263 	info = kzalloc_obj(*info, GFP_KERNEL);
264 	if (!info)
265 		return -ENOMEM;
266 
267 	ret = appletbdrm_send_msg(adev, APPLETBDRM_MSG_GET_INFORMATION);
268 	if (ret)
269 		return ret;
270 
271 	ret = appletbdrm_read_response(adev, &info->header, sizeof(*info),
272 				       APPLETBDRM_MSG_GET_INFORMATION);
273 	if (ret)
274 		goto free_info;
275 
276 	bits_per_pixel = info->bits_per_pixel;
277 	pixel_format = get_unaligned(&info->pixel_format);
278 
279 	adev->width = get_unaligned_le32(&info->width);
280 	adev->height = get_unaligned_le32(&info->height);
281 
282 	if (bits_per_pixel != APPLETBDRM_BITS_PER_PIXEL) {
283 		drm_err(drm, "Encountered unexpected bits per pixel value (%d)\n", bits_per_pixel);
284 		ret = -EINVAL;
285 		goto free_info;
286 	}
287 
288 	if (pixel_format != APPLETBDRM_PIXEL_FORMAT) {
289 		drm_err(drm, "Encountered unknown pixel format (%p4cl)\n", &pixel_format);
290 		ret = -EINVAL;
291 		goto free_info;
292 	}
293 
294 free_info:
295 	kfree(info);
296 
297 	return ret;
298 }
299 
300 static u32 rect_size(struct drm_rect *rect)
301 {
302 	return drm_rect_width(rect) * drm_rect_height(rect) *
303 		(BITS_TO_BYTES(APPLETBDRM_BITS_PER_PIXEL));
304 }
305 
306 static int appletbdrm_connector_helper_get_modes(struct drm_connector *connector)
307 {
308 	struct appletbdrm_device *adev = drm_to_adev(connector->dev);
309 
310 	return drm_connector_helper_get_modes_fixed(connector, &adev->mode);
311 }
312 
313 static const u32 appletbdrm_primary_plane_formats[] = {
314 	DRM_FORMAT_BGR888,
315 	DRM_FORMAT_XRGB8888, /* emulated */
316 };
317 
318 static int appletbdrm_primary_plane_helper_atomic_check(struct drm_plane *plane,
319 						   struct drm_atomic_state *state)
320 {
321 	struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state, plane);
322 	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
323 	struct drm_crtc *new_crtc = new_plane_state->crtc;
324 	struct drm_crtc_state *new_crtc_state = NULL;
325 	struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(new_plane_state);
326 	struct drm_atomic_helper_damage_iter iter;
327 	struct drm_rect damage;
328 	size_t frames_size = 0;
329 	size_t request_size;
330 	int ret;
331 
332 	if (new_crtc)
333 		new_crtc_state = drm_atomic_get_new_crtc_state(state, new_crtc);
334 
335 	ret = drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state,
336 						  DRM_PLANE_NO_SCALING,
337 						  DRM_PLANE_NO_SCALING,
338 						  false, false);
339 	if (ret)
340 		return ret;
341 	else if (!new_plane_state->visible)
342 		return 0;
343 
344 	drm_atomic_helper_damage_iter_init(&iter, old_plane_state, new_plane_state);
345 	drm_atomic_for_each_plane_damage(&iter, &damage) {
346 		frames_size += struct_size((struct appletbdrm_frame *)0, buf, rect_size(&damage));
347 	}
348 
349 	if (!frames_size)
350 		return 0;
351 
352 	request_size = ALIGN(sizeof(struct appletbdrm_fb_request) +
353 		       frames_size +
354 		       sizeof(struct appletbdrm_fb_request_footer), 16);
355 
356 	appletbdrm_state->request = kzalloc(request_size, GFP_KERNEL);
357 
358 	if (!appletbdrm_state->request)
359 		return -ENOMEM;
360 
361 	appletbdrm_state->response = kzalloc_obj(*appletbdrm_state->response,
362 						 GFP_KERNEL);
363 
364 	if (!appletbdrm_state->response)
365 		return -ENOMEM;
366 
367 	appletbdrm_state->request_size = request_size;
368 	appletbdrm_state->frames_size = frames_size;
369 
370 	return 0;
371 }
372 
373 static int appletbdrm_flush_damage(struct appletbdrm_device *adev,
374 				   struct drm_plane_state *old_state,
375 				   struct drm_plane_state *state)
376 {
377 	struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(state);
378 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
379 	struct appletbdrm_fb_request_response *response = appletbdrm_state->response;
380 	struct appletbdrm_fb_request_footer *footer;
381 	struct drm_atomic_helper_damage_iter iter;
382 	struct drm_framebuffer *fb = state->fb;
383 	struct appletbdrm_fb_request *request = appletbdrm_state->request;
384 	struct drm_device *drm = &adev->drm;
385 	struct appletbdrm_frame *frame;
386 	u64 timestamp = ktime_get_ns();
387 	struct drm_rect damage;
388 	size_t frames_size = appletbdrm_state->frames_size;
389 	size_t request_size = appletbdrm_state->request_size;
390 	int ret;
391 
392 	if (!frames_size)
393 		return 0;
394 
395 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
396 	if (ret) {
397 		drm_err(drm, "Failed to start CPU framebuffer access (%d)\n", ret);
398 		goto end_fb_cpu_access;
399 	}
400 
401 	request->header.unk_00 = cpu_to_le16(2);
402 	request->header.unk_02 = cpu_to_le16(0x12);
403 	request->header.unk_04 = cpu_to_le32(9);
404 	request->header.size = cpu_to_le32(request_size - sizeof(request->header));
405 	request->unk_10 = cpu_to_le16(1);
406 	request->msg_id = timestamp;
407 
408 	frame = (struct appletbdrm_frame *)request->data;
409 
410 	drm_atomic_helper_damage_iter_init(&iter, old_state, state);
411 	drm_atomic_for_each_plane_damage(&iter, &damage) {
412 		struct drm_rect dst_clip = state->dst;
413 		struct iosys_map dst = IOSYS_MAP_INIT_VADDR(frame->buf);
414 		u32 buf_size = rect_size(&damage);
415 
416 		if (!drm_rect_intersect(&dst_clip, &damage))
417 			continue;
418 
419 		/*
420 		 * The coordinates need to be translated to the coordinate
421 		 * system the device expects, see the comment in
422 		 * appletbdrm_setup_mode_config
423 		 */
424 		frame->begin_x = cpu_to_le16(damage.y1);
425 		frame->begin_y = cpu_to_le16(adev->height - damage.x2);
426 		frame->width = cpu_to_le16(drm_rect_height(&damage));
427 		frame->height = cpu_to_le16(drm_rect_width(&damage));
428 		frame->buf_size = cpu_to_le32(buf_size);
429 
430 		switch (fb->format->format) {
431 		case DRM_FORMAT_XRGB8888:
432 			drm_fb_xrgb8888_to_bgr888(&dst, NULL, &shadow_plane_state->data[0], fb, &damage, &shadow_plane_state->fmtcnv_state);
433 			break;
434 		default:
435 			drm_fb_memcpy(&dst, NULL, &shadow_plane_state->data[0], fb, &damage);
436 			break;
437 		}
438 
439 		frame = (void *)frame + struct_size(frame, buf, buf_size);
440 	}
441 
442 	footer = (struct appletbdrm_fb_request_footer *)&request->data[frames_size];
443 
444 	footer->unk_0c = cpu_to_le32(0xfffe);
445 	footer->unk_1c = cpu_to_le32(0x80001);
446 	footer->unk_34 = cpu_to_le32(0x80002);
447 	footer->unk_4c = cpu_to_le32(0xffff);
448 	footer->timestamp = cpu_to_le64(timestamp);
449 
450 	ret = appletbdrm_send_request(adev, &request->header, request_size);
451 	if (ret)
452 		goto end_fb_cpu_access;
453 
454 	ret = appletbdrm_read_response(adev, &response->header, sizeof(*response),
455 				       APPLETBDRM_MSG_UPDATE_COMPLETE);
456 	if (ret)
457 		goto end_fb_cpu_access;
458 
459 	if (response->timestamp != footer->timestamp) {
460 		drm_err(drm, "Response timestamp (%llu) doesn't match request timestamp (%llu)\n",
461 			le64_to_cpu(response->timestamp), timestamp);
462 		goto end_fb_cpu_access;
463 	}
464 
465 end_fb_cpu_access:
466 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
467 
468 	return ret;
469 }
470 
471 static void appletbdrm_primary_plane_helper_atomic_update(struct drm_plane *plane,
472 						     struct drm_atomic_state *old_state)
473 {
474 	struct appletbdrm_device *adev = drm_to_adev(plane->dev);
475 	struct drm_device *drm = plane->dev;
476 	struct drm_plane_state *plane_state = plane->state;
477 	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(old_state, plane);
478 	int idx;
479 
480 	if (!drm_dev_enter(drm, &idx))
481 		return;
482 
483 	appletbdrm_flush_damage(adev, old_plane_state, plane_state);
484 
485 	drm_dev_exit(idx);
486 }
487 
488 static void appletbdrm_primary_plane_helper_atomic_disable(struct drm_plane *plane,
489 							   struct drm_atomic_state *state)
490 {
491 	struct drm_device *dev = plane->dev;
492 	struct appletbdrm_device *adev = drm_to_adev(dev);
493 	int idx;
494 
495 	if (!drm_dev_enter(dev, &idx))
496 		return;
497 
498 	appletbdrm_clear_display(adev);
499 
500 	drm_dev_exit(idx);
501 }
502 
503 static void appletbdrm_primary_plane_reset(struct drm_plane *plane)
504 {
505 	struct appletbdrm_plane_state *appletbdrm_state;
506 
507 	WARN_ON(plane->state);
508 
509 	appletbdrm_state = kzalloc_obj(*appletbdrm_state, GFP_KERNEL);
510 	if (!appletbdrm_state)
511 		return;
512 
513 	__drm_gem_reset_shadow_plane(plane, &appletbdrm_state->base);
514 }
515 
516 static struct drm_plane_state *appletbdrm_primary_plane_duplicate_state(struct drm_plane *plane)
517 {
518 	struct drm_shadow_plane_state *new_shadow_plane_state;
519 	struct appletbdrm_plane_state *appletbdrm_state;
520 
521 	if (WARN_ON(!plane->state))
522 		return NULL;
523 
524 	appletbdrm_state = kzalloc_obj(*appletbdrm_state, GFP_KERNEL);
525 	if (!appletbdrm_state)
526 		return NULL;
527 
528 	/* Request and response are not duplicated and are allocated in .atomic_check */
529 	appletbdrm_state->request = NULL;
530 	appletbdrm_state->response = NULL;
531 
532 	appletbdrm_state->request_size = 0;
533 	appletbdrm_state->frames_size = 0;
534 
535 	new_shadow_plane_state = &appletbdrm_state->base;
536 
537 	__drm_gem_duplicate_shadow_plane_state(plane, new_shadow_plane_state);
538 
539 	return &new_shadow_plane_state->base;
540 }
541 
542 static void appletbdrm_primary_plane_destroy_state(struct drm_plane *plane,
543 						   struct drm_plane_state *state)
544 {
545 	struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(state);
546 
547 	kfree(appletbdrm_state->request);
548 	kfree(appletbdrm_state->response);
549 
550 	__drm_gem_destroy_shadow_plane_state(&appletbdrm_state->base);
551 
552 	kfree(appletbdrm_state);
553 }
554 
555 static const struct drm_plane_helper_funcs appletbdrm_primary_plane_helper_funcs = {
556 	DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
557 	.atomic_check = appletbdrm_primary_plane_helper_atomic_check,
558 	.atomic_update = appletbdrm_primary_plane_helper_atomic_update,
559 	.atomic_disable = appletbdrm_primary_plane_helper_atomic_disable,
560 };
561 
562 static const struct drm_plane_funcs appletbdrm_primary_plane_funcs = {
563 	.update_plane = drm_atomic_helper_update_plane,
564 	.disable_plane = drm_atomic_helper_disable_plane,
565 	.reset = appletbdrm_primary_plane_reset,
566 	.atomic_duplicate_state = appletbdrm_primary_plane_duplicate_state,
567 	.atomic_destroy_state = appletbdrm_primary_plane_destroy_state,
568 	.destroy = drm_plane_cleanup,
569 };
570 
571 static enum drm_mode_status appletbdrm_crtc_helper_mode_valid(struct drm_crtc *crtc,
572 							  const struct drm_display_mode *mode)
573 {
574 	struct appletbdrm_device *adev = drm_to_adev(crtc->dev);
575 
576 	return drm_crtc_helper_mode_valid_fixed(crtc, mode, &adev->mode);
577 }
578 
579 static const struct drm_mode_config_funcs appletbdrm_mode_config_funcs = {
580 	.fb_create = drm_gem_fb_create_with_dirty,
581 	.atomic_check = drm_atomic_helper_check,
582 	.atomic_commit = drm_atomic_helper_commit,
583 };
584 
585 static const struct drm_connector_funcs appletbdrm_connector_funcs = {
586 	.reset = drm_atomic_helper_connector_reset,
587 	.destroy = drm_connector_cleanup,
588 	.fill_modes = drm_helper_probe_single_connector_modes,
589 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
590 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
591 };
592 
593 static const struct drm_connector_helper_funcs appletbdrm_connector_helper_funcs = {
594 	.get_modes = appletbdrm_connector_helper_get_modes,
595 };
596 
597 static const struct drm_crtc_helper_funcs appletbdrm_crtc_helper_funcs = {
598 	.mode_valid = appletbdrm_crtc_helper_mode_valid,
599 };
600 
601 static const struct drm_crtc_funcs appletbdrm_crtc_funcs = {
602 	.reset = drm_atomic_helper_crtc_reset,
603 	.destroy = drm_crtc_cleanup,
604 	.set_config = drm_atomic_helper_set_config,
605 	.page_flip = drm_atomic_helper_page_flip,
606 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
607 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
608 };
609 
610 static const struct drm_encoder_funcs appletbdrm_encoder_funcs = {
611 	.destroy = drm_encoder_cleanup,
612 };
613 
614 DEFINE_DRM_GEM_FOPS(appletbdrm_drm_fops);
615 
616 static const struct drm_driver appletbdrm_drm_driver = {
617 	DRM_GEM_SHMEM_DRIVER_OPS,
618 	.name			= "appletbdrm",
619 	.desc			= "Apple Touch Bar DRM Driver",
620 	.major			= 1,
621 	.minor			= 0,
622 	.driver_features	= DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
623 	.fops			= &appletbdrm_drm_fops,
624 };
625 
626 static int appletbdrm_setup_mode_config(struct appletbdrm_device *adev)
627 {
628 	struct drm_connector *connector = &adev->connector;
629 	struct drm_plane *primary_plane;
630 	struct drm_crtc *crtc;
631 	struct drm_encoder *encoder;
632 	struct drm_device *drm = &adev->drm;
633 	int ret;
634 
635 	ret = drmm_mode_config_init(drm);
636 	if (ret) {
637 		drm_err(drm, "Failed to initialize mode configuration\n");
638 		return ret;
639 	}
640 
641 	primary_plane = &adev->primary_plane;
642 	ret = drm_universal_plane_init(drm, primary_plane, 0,
643 				       &appletbdrm_primary_plane_funcs,
644 				       appletbdrm_primary_plane_formats,
645 				       ARRAY_SIZE(appletbdrm_primary_plane_formats),
646 				       NULL,
647 				       DRM_PLANE_TYPE_PRIMARY, NULL);
648 	if (ret) {
649 		drm_err(drm, "Failed to initialize universal plane object\n");
650 		return ret;
651 	}
652 
653 	drm_plane_helper_add(primary_plane, &appletbdrm_primary_plane_helper_funcs);
654 	drm_plane_enable_fb_damage_clips(primary_plane);
655 
656 	crtc = &adev->crtc;
657 	ret = drm_crtc_init_with_planes(drm, crtc, primary_plane, NULL,
658 					&appletbdrm_crtc_funcs, NULL);
659 	if (ret) {
660 		drm_err(drm, "Failed to initialize CRTC object\n");
661 		return ret;
662 	}
663 
664 	drm_crtc_helper_add(crtc, &appletbdrm_crtc_helper_funcs);
665 
666 	encoder = &adev->encoder;
667 	ret = drm_encoder_init(drm, encoder, &appletbdrm_encoder_funcs,
668 			       DRM_MODE_ENCODER_DAC, NULL);
669 	if (ret) {
670 		drm_err(drm, "Failed to initialize encoder\n");
671 		return ret;
672 	}
673 
674 	encoder->possible_crtcs = drm_crtc_mask(crtc);
675 
676 	/*
677 	 * The coordinate system used by the device is different from the
678 	 * coordinate system of the framebuffer in that the x and y axes are
679 	 * swapped, and that the y axis is inverted; so what the device reports
680 	 * as the height is actually the width of the framebuffer and vice
681 	 * versa.
682 	 */
683 	drm->mode_config.max_width = max(adev->height, DRM_SHADOW_PLANE_MAX_WIDTH);
684 	drm->mode_config.max_height = max(adev->width, DRM_SHADOW_PLANE_MAX_HEIGHT);
685 	drm->mode_config.preferred_depth = APPLETBDRM_BITS_PER_PIXEL;
686 	drm->mode_config.funcs = &appletbdrm_mode_config_funcs;
687 
688 	adev->mode = (struct drm_display_mode) {
689 		DRM_MODE_INIT(60, adev->height, adev->width,
690 			      DRM_MODE_RES_MM(adev->height, 218),
691 			      DRM_MODE_RES_MM(adev->width, 218))
692 	};
693 
694 	ret = drm_connector_init(drm, connector,
695 				 &appletbdrm_connector_funcs, DRM_MODE_CONNECTOR_USB);
696 	if (ret) {
697 		drm_err(drm, "Failed to initialize connector\n");
698 		return ret;
699 	}
700 
701 	drm_connector_helper_add(connector, &appletbdrm_connector_helper_funcs);
702 
703 	ret = drm_connector_set_panel_orientation(connector,
704 						  DRM_MODE_PANEL_ORIENTATION_RIGHT_UP);
705 	if (ret) {
706 		drm_err(drm, "Failed to set panel orientation\n");
707 		return ret;
708 	}
709 
710 	connector->display_info.non_desktop = true;
711 	ret = drm_object_property_set_value(&connector->base,
712 					    drm->mode_config.non_desktop_property, true);
713 	if (ret) {
714 		drm_err(drm, "Failed to set non-desktop property\n");
715 		return ret;
716 	}
717 
718 	ret = drm_connector_attach_encoder(connector, encoder);
719 
720 	if (ret) {
721 		drm_err(drm, "Failed to initialize simple display pipe\n");
722 		return ret;
723 	}
724 
725 	drm_mode_config_reset(drm);
726 
727 	return 0;
728 }
729 
730 static int appletbdrm_probe(struct usb_interface *intf,
731 			    const struct usb_device_id *id)
732 {
733 	struct usb_endpoint_descriptor *bulk_in, *bulk_out;
734 	struct device *dev = &intf->dev;
735 	struct appletbdrm_device *adev;
736 	struct drm_device *drm = NULL;
737 	struct device *dma_dev;
738 	int ret;
739 
740 	ret = usb_find_common_endpoints(intf->cur_altsetting, &bulk_in, &bulk_out, NULL, NULL);
741 	if (ret) {
742 		drm_err(drm, "appletbdrm: Failed to find bulk endpoints\n");
743 		return ret;
744 	}
745 
746 	adev = devm_drm_dev_alloc(dev, &appletbdrm_drm_driver, struct appletbdrm_device, drm);
747 	if (IS_ERR(adev))
748 		return PTR_ERR(adev);
749 
750 	adev->in_ep = bulk_in->bEndpointAddress;
751 	adev->out_ep = bulk_out->bEndpointAddress;
752 
753 	drm = &adev->drm;
754 
755 	usb_set_intfdata(intf, adev);
756 
757 	dma_dev = usb_intf_get_dma_device(intf);
758 	if (dma_dev) {
759 		drm_dev_set_dma_dev(drm, dma_dev);
760 		put_device(dma_dev);
761 	} else {
762 		drm_warn(drm, "buffer sharing not supported"); /* not an error */
763 	}
764 
765 	ret = appletbdrm_get_information(adev);
766 	if (ret) {
767 		drm_err(drm, "Failed to get display information\n");
768 		return ret;
769 	}
770 
771 	ret = appletbdrm_signal_readiness(adev);
772 	if (ret) {
773 		drm_err(drm, "Failed to signal readiness\n");
774 		return ret;
775 	}
776 
777 	ret = appletbdrm_setup_mode_config(adev);
778 	if (ret) {
779 		drm_err(drm, "Failed to setup mode config\n");
780 		return ret;
781 	}
782 
783 	ret = drm_dev_register(drm, 0);
784 	if (ret) {
785 		drm_err(drm, "Failed to register DRM device\n");
786 		return ret;
787 	}
788 
789 	ret = appletbdrm_clear_display(adev);
790 	if (ret) {
791 		drm_err(drm, "Failed to clear display\n");
792 		return ret;
793 	}
794 
795 	return 0;
796 }
797 
798 static void appletbdrm_disconnect(struct usb_interface *intf)
799 {
800 	struct appletbdrm_device *adev = usb_get_intfdata(intf);
801 	struct drm_device *drm = &adev->drm;
802 
803 	drm_dev_unplug(drm);
804 	drm_atomic_helper_shutdown(drm);
805 }
806 
807 static void appletbdrm_shutdown(struct usb_interface *intf)
808 {
809 	struct appletbdrm_device *adev = usb_get_intfdata(intf);
810 
811 	/*
812 	 * The framebuffer needs to be cleared on shutdown since its content
813 	 * persists across boots
814 	 */
815 	drm_atomic_helper_shutdown(&adev->drm);
816 }
817 
818 static const struct usb_device_id appletbdrm_usb_id_table[] = {
819 	{ USB_DEVICE_INTERFACE_CLASS(0x05ac, 0x8302, USB_CLASS_AUDIO_VIDEO) },
820 	{}
821 };
822 MODULE_DEVICE_TABLE(usb, appletbdrm_usb_id_table);
823 
824 static struct usb_driver appletbdrm_usb_driver = {
825 	.name		= "appletbdrm",
826 	.probe		= appletbdrm_probe,
827 	.disconnect	= appletbdrm_disconnect,
828 	.shutdown	= appletbdrm_shutdown,
829 	.id_table	= appletbdrm_usb_id_table,
830 };
831 module_usb_driver(appletbdrm_usb_driver);
832 
833 MODULE_AUTHOR("Kerem Karabay <kekrby@gmail.com>");
834 MODULE_DESCRIPTION("Apple Touch Bar DRM Driver");
835 MODULE_LICENSE("GPL");
836