xref: /linux/drivers/gpu/drm/gud/gud_pipe.c (revision 68a052239fc4b351e961f698b824f7654a346091)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright 2020 Noralf Trønnes
4  */
5 
6 #include <linux/lz4.h>
7 #include <linux/usb.h>
8 #include <linux/vmalloc.h>
9 #include <linux/workqueue.h>
10 
11 #include <drm/drm_atomic.h>
12 #include <drm/drm_connector.h>
13 #include <drm/drm_damage_helper.h>
14 #include <drm/drm_drv.h>
15 #include <drm/drm_format_helper.h>
16 #include <drm/drm_fourcc.h>
17 #include <drm/drm_framebuffer.h>
18 #include <drm/drm_gem.h>
19 #include <drm/drm_gem_atomic_helper.h>
20 #include <drm/drm_gem_framebuffer_helper.h>
21 #include <drm/drm_print.h>
22 #include <drm/drm_rect.h>
23 #include <drm/gud.h>
24 
25 #include "gud_internal.h"
26 
27 /*
28  * Some userspace rendering loops run all displays in the same loop.
29  * This means that a fast display will have to wait for a slow one.
30  * Such users might want to enable this module parameter.
31  */
32 static bool gud_async_flush;
33 module_param_named(async_flush, gud_async_flush, bool, 0644);
34 MODULE_PARM_DESC(async_flush, "Enable asynchronous flushing [default=0]");
35 
36 /*
37  * FIXME: The driver is probably broken on Big Endian machines.
38  * See discussion:
39  * https://lore.kernel.org/dri-devel/CAKb7UvihLX0hgBOP3VBG7O+atwZcUVCPVuBdfmDMpg0NjXe-cQ@mail.gmail.com/
40  */
41 
42 static bool gud_is_big_endian(void)
43 {
44 #if defined(__BIG_ENDIAN)
45 	return true;
46 #else
47 	return false;
48 #endif
49 }
50 
51 static size_t gud_xrgb8888_to_r124(u8 *dst, const struct drm_format_info *format,
52 				   void *src, struct drm_framebuffer *fb,
53 				   struct drm_rect *rect,
54 				   struct drm_format_conv_state *fmtcnv_state)
55 {
56 	unsigned int block_width = drm_format_info_block_width(format, 0);
57 	unsigned int bits_per_pixel = 8 / block_width;
58 	unsigned int x, y, width, height;
59 	u8 pix, *pix8, *block = dst; /* Assign to silence compiler warning */
60 	struct iosys_map dst_map, vmap;
61 	size_t len;
62 	void *buf;
63 
64 	WARN_ON_ONCE(format->char_per_block[0] != 1);
65 
66 	/* Start on a byte boundary */
67 	rect->x1 = ALIGN_DOWN(rect->x1, block_width);
68 	width = drm_rect_width(rect);
69 	height = drm_rect_height(rect);
70 	len = drm_format_info_min_pitch(format, 0, width) * height;
71 
72 	buf = kmalloc(width * height, GFP_KERNEL);
73 	if (!buf)
74 		return 0;
75 
76 	iosys_map_set_vaddr(&dst_map, buf);
77 	iosys_map_set_vaddr(&vmap, src);
78 	drm_fb_xrgb8888_to_gray8(&dst_map, NULL, &vmap, fb, rect, fmtcnv_state);
79 	pix8 = buf;
80 
81 	for (y = 0; y < height; y++) {
82 		for (x = 0; x < width; x++) {
83 			unsigned int pixpos = x % block_width; /* within byte from the left */
84 			unsigned int pixshift = (block_width - pixpos - 1) * bits_per_pixel;
85 
86 			if (!pixpos) {
87 				block = dst++;
88 				*block = 0;
89 			}
90 
91 			pix = (*pix8++) >> (8 - bits_per_pixel);
92 			*block |= pix << pixshift;
93 		}
94 	}
95 
96 	kfree(buf);
97 
98 	return len;
99 }
100 
101 static size_t gud_xrgb8888_to_color(u8 *dst, const struct drm_format_info *format,
102 				    void *src, struct drm_framebuffer *fb,
103 				    struct drm_rect *rect)
104 {
105 	unsigned int block_width = drm_format_info_block_width(format, 0);
106 	unsigned int bits_per_pixel = 8 / block_width;
107 	u8 r, g, b, pix, *block = dst; /* Assign to silence compiler warning */
108 	unsigned int x, y, width;
109 	__le32 *sbuf32;
110 	u32 pix32;
111 	size_t len;
112 
113 	/* Start on a byte boundary */
114 	rect->x1 = ALIGN_DOWN(rect->x1, block_width);
115 	width = drm_rect_width(rect);
116 	len = drm_format_info_min_pitch(format, 0, width) * drm_rect_height(rect);
117 
118 	for (y = rect->y1; y < rect->y2; y++) {
119 		sbuf32 = src + (y * fb->pitches[0]);
120 		sbuf32 += rect->x1;
121 
122 		for (x = 0; x < width; x++) {
123 			unsigned int pixpos = x % block_width; /* within byte from the left */
124 			unsigned int pixshift = (block_width - pixpos - 1) * bits_per_pixel;
125 
126 			if (!pixpos) {
127 				block = dst++;
128 				*block = 0;
129 			}
130 
131 			pix32 = le32_to_cpu(*sbuf32++);
132 			r = pix32 >> 16;
133 			g = pix32 >> 8;
134 			b = pix32;
135 
136 			switch (format->format) {
137 			case GUD_DRM_FORMAT_XRGB1111:
138 				pix = ((r >> 7) << 2) | ((g >> 7) << 1) | (b >> 7);
139 				break;
140 			default:
141 				WARN_ON_ONCE(1);
142 				return len;
143 			}
144 
145 			*block |= pix << pixshift;
146 		}
147 	}
148 
149 	return len;
150 }
151 
152 static int gud_prep_flush(struct gud_device *gdrm, struct drm_framebuffer *fb,
153 			  const struct iosys_map *src, bool cached_reads,
154 			  const struct drm_format_info *format, struct drm_rect *rect,
155 			  struct gud_set_buffer_req *req,
156 			  struct drm_format_conv_state *fmtcnv_state)
157 {
158 	u8 compression = gdrm->compression;
159 	struct iosys_map dst;
160 	void *vaddr, *buf;
161 	size_t pitch, len;
162 
163 	pitch = drm_format_info_min_pitch(format, 0, drm_rect_width(rect));
164 	len = pitch * drm_rect_height(rect);
165 	if (len > gdrm->bulk_len)
166 		return -E2BIG;
167 
168 	vaddr = src[0].vaddr;
169 retry:
170 	if (compression)
171 		buf = gdrm->compress_buf;
172 	else
173 		buf = gdrm->bulk_buf;
174 	iosys_map_set_vaddr(&dst, buf);
175 
176 	/*
177 	 * Imported buffers are assumed to be write-combined and thus uncached
178 	 * with slow reads (at least on ARM).
179 	 */
180 	if (format != fb->format) {
181 		if (format->format == GUD_DRM_FORMAT_R1) {
182 			len = gud_xrgb8888_to_r124(buf, format, vaddr, fb, rect, fmtcnv_state);
183 			if (!len)
184 				return -ENOMEM;
185 		} else if (format->format == DRM_FORMAT_R8) {
186 			drm_fb_xrgb8888_to_gray8(&dst, NULL, src, fb, rect, fmtcnv_state);
187 		} else if (format->format == DRM_FORMAT_RGB332) {
188 			drm_fb_xrgb8888_to_rgb332(&dst, NULL, src, fb, rect, fmtcnv_state);
189 		} else if (format->format == DRM_FORMAT_RGB565) {
190 			if (gud_is_big_endian()) {
191 				drm_fb_xrgb8888_to_rgb565be(&dst, NULL, src, fb, rect,
192 							    fmtcnv_state);
193 			} else {
194 				drm_fb_xrgb8888_to_rgb565(&dst, NULL, src, fb, rect,
195 							  fmtcnv_state);
196 			}
197 		} else if (format->format == DRM_FORMAT_RGB888) {
198 			drm_fb_xrgb8888_to_rgb888(&dst, NULL, src, fb, rect, fmtcnv_state);
199 		} else {
200 			len = gud_xrgb8888_to_color(buf, format, vaddr, fb, rect);
201 		}
202 	} else if (gud_is_big_endian() && format->cpp[0] > 1) {
203 		drm_fb_swab(&dst, NULL, src, fb, rect, cached_reads, fmtcnv_state);
204 	} else if (compression && cached_reads && pitch == fb->pitches[0]) {
205 		/* can compress directly from the framebuffer */
206 		buf = vaddr + rect->y1 * pitch;
207 	} else {
208 		drm_fb_memcpy(&dst, NULL, src, fb, rect);
209 	}
210 
211 	memset(req, 0, sizeof(*req));
212 	req->x = cpu_to_le32(rect->x1);
213 	req->y = cpu_to_le32(rect->y1);
214 	req->width = cpu_to_le32(drm_rect_width(rect));
215 	req->height = cpu_to_le32(drm_rect_height(rect));
216 	req->length = cpu_to_le32(len);
217 
218 	if (compression & GUD_COMPRESSION_LZ4) {
219 		int complen;
220 
221 		complen = LZ4_compress_default(buf, gdrm->bulk_buf, len, len, gdrm->lz4_comp_mem);
222 		if (complen <= 0) {
223 			compression = 0;
224 			goto retry;
225 		}
226 
227 		req->compression = GUD_COMPRESSION_LZ4;
228 		req->compressed_length = cpu_to_le32(complen);
229 	}
230 
231 	return 0;
232 }
233 
234 struct gud_usb_bulk_context {
235 	struct timer_list timer;
236 	struct usb_sg_request sgr;
237 };
238 
239 static void gud_usb_bulk_timeout(struct timer_list *t)
240 {
241 	struct gud_usb_bulk_context *ctx = timer_container_of(ctx, t, timer);
242 
243 	usb_sg_cancel(&ctx->sgr);
244 }
245 
246 static int gud_usb_bulk(struct gud_device *gdrm, size_t len)
247 {
248 	struct gud_usb_bulk_context ctx;
249 	int ret;
250 
251 	ret = usb_sg_init(&ctx.sgr, gud_to_usb_device(gdrm), gdrm->bulk_pipe, 0,
252 			  gdrm->bulk_sgt.sgl, gdrm->bulk_sgt.nents, len, GFP_KERNEL);
253 	if (ret)
254 		return ret;
255 
256 	timer_setup_on_stack(&ctx.timer, gud_usb_bulk_timeout, 0);
257 	mod_timer(&ctx.timer, jiffies + msecs_to_jiffies(3000));
258 
259 	usb_sg_wait(&ctx.sgr);
260 
261 	if (!timer_delete_sync(&ctx.timer))
262 		ret = -ETIMEDOUT;
263 	else if (ctx.sgr.status < 0)
264 		ret = ctx.sgr.status;
265 	else if (ctx.sgr.bytes != len)
266 		ret = -EIO;
267 
268 	timer_destroy_on_stack(&ctx.timer);
269 
270 	return ret;
271 }
272 
273 static int gud_flush_rect(struct gud_device *gdrm, struct drm_framebuffer *fb,
274 			  const struct iosys_map *src, bool cached_reads,
275 			  const struct drm_format_info *format, struct drm_rect *rect,
276 			  struct drm_format_conv_state *fmtcnv_state)
277 {
278 	struct gud_set_buffer_req req;
279 	size_t len, trlen;
280 	int ret;
281 
282 	drm_dbg(&gdrm->drm, "Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect));
283 
284 	ret = gud_prep_flush(gdrm, fb, src, cached_reads, format, rect, &req, fmtcnv_state);
285 	if (ret)
286 		return ret;
287 
288 	len = le32_to_cpu(req.length);
289 
290 	if (req.compression)
291 		trlen = le32_to_cpu(req.compressed_length);
292 	else
293 		trlen = len;
294 
295 	gdrm->stats_length += len;
296 	/* Did it wrap around? */
297 	if (gdrm->stats_length <= len && gdrm->stats_actual_length) {
298 		gdrm->stats_length = len;
299 		gdrm->stats_actual_length = 0;
300 	}
301 	gdrm->stats_actual_length += trlen;
302 
303 	if (!(gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE) || gdrm->prev_flush_failed) {
304 		ret = gud_usb_set(gdrm, GUD_REQ_SET_BUFFER, 0, &req, sizeof(req));
305 		if (ret)
306 			return ret;
307 	}
308 
309 	ret = gud_usb_bulk(gdrm, trlen);
310 	if (ret)
311 		gdrm->stats_num_errors++;
312 
313 	return ret;
314 }
315 
316 void gud_clear_damage(struct gud_device *gdrm)
317 {
318 	gdrm->damage.x1 = INT_MAX;
319 	gdrm->damage.y1 = INT_MAX;
320 	gdrm->damage.x2 = 0;
321 	gdrm->damage.y2 = 0;
322 }
323 
324 static void gud_flush_damage(struct gud_device *gdrm, struct drm_framebuffer *fb,
325 			     const struct iosys_map *src, bool cached_reads,
326 			     struct drm_rect *damage)
327 {
328 	struct drm_format_conv_state fmtcnv_state = DRM_FORMAT_CONV_STATE_INIT;
329 	const struct drm_format_info *format;
330 	unsigned int i, lines;
331 	size_t pitch;
332 	int ret;
333 
334 	format = fb->format;
335 	if (format->format == DRM_FORMAT_XRGB8888 && gdrm->xrgb8888_emulation_format)
336 		format = gdrm->xrgb8888_emulation_format;
337 
338 	/* Split update if it's too big */
339 	pitch = drm_format_info_min_pitch(format, 0, drm_rect_width(damage));
340 	lines = drm_rect_height(damage);
341 
342 	if (gdrm->bulk_len < lines * pitch)
343 		lines = gdrm->bulk_len / pitch;
344 
345 	for (i = 0; i < DIV_ROUND_UP(drm_rect_height(damage), lines); i++) {
346 		struct drm_rect rect = *damage;
347 
348 		rect.y1 += i * lines;
349 		rect.y2 = min_t(u32, rect.y1 + lines, damage->y2);
350 
351 		ret = gud_flush_rect(gdrm, fb, src, cached_reads, format, &rect, &fmtcnv_state);
352 		if (ret) {
353 			if (ret != -ENODEV && ret != -ECONNRESET &&
354 			    ret != -ESHUTDOWN && ret != -EPROTO)
355 				dev_err_ratelimited(fb->dev->dev,
356 						    "Failed to flush framebuffer: error=%d\n", ret);
357 			gdrm->prev_flush_failed = true;
358 			break;
359 		}
360 	}
361 
362 	drm_format_conv_state_release(&fmtcnv_state);
363 }
364 
365 void gud_flush_work(struct work_struct *work)
366 {
367 	struct gud_device *gdrm = container_of(work, struct gud_device, work);
368 	struct iosys_map shadow_map;
369 	struct drm_framebuffer *fb;
370 	struct drm_rect damage;
371 	int idx;
372 
373 	if (!drm_dev_enter(&gdrm->drm, &idx))
374 		return;
375 
376 	mutex_lock(&gdrm->damage_lock);
377 	fb = gdrm->fb;
378 	gdrm->fb = NULL;
379 	iosys_map_set_vaddr(&shadow_map, gdrm->shadow_buf);
380 	damage = gdrm->damage;
381 	gud_clear_damage(gdrm);
382 	mutex_unlock(&gdrm->damage_lock);
383 
384 	if (!fb)
385 		goto out;
386 
387 	gud_flush_damage(gdrm, fb, &shadow_map, true, &damage);
388 
389 	drm_framebuffer_put(fb);
390 out:
391 	drm_dev_exit(idx);
392 }
393 
394 static int gud_fb_queue_damage(struct gud_device *gdrm, struct drm_framebuffer *fb,
395 			       const struct iosys_map *src, struct drm_rect *damage)
396 {
397 	struct drm_framebuffer *old_fb = NULL;
398 	struct iosys_map shadow_map;
399 
400 	mutex_lock(&gdrm->damage_lock);
401 
402 	if (!gdrm->shadow_buf) {
403 		gdrm->shadow_buf = vcalloc(fb->pitches[0], fb->height);
404 		if (!gdrm->shadow_buf) {
405 			mutex_unlock(&gdrm->damage_lock);
406 			return -ENOMEM;
407 		}
408 	}
409 
410 	iosys_map_set_vaddr(&shadow_map, gdrm->shadow_buf);
411 	iosys_map_incr(&shadow_map, drm_fb_clip_offset(fb->pitches[0], fb->format, damage));
412 	drm_fb_memcpy(&shadow_map, fb->pitches, src, fb, damage);
413 
414 	if (fb != gdrm->fb) {
415 		old_fb = gdrm->fb;
416 		drm_framebuffer_get(fb);
417 		gdrm->fb = fb;
418 	}
419 
420 	gdrm->damage.x1 = min(gdrm->damage.x1, damage->x1);
421 	gdrm->damage.y1 = min(gdrm->damage.y1, damage->y1);
422 	gdrm->damage.x2 = max(gdrm->damage.x2, damage->x2);
423 	gdrm->damage.y2 = max(gdrm->damage.y2, damage->y2);
424 
425 	mutex_unlock(&gdrm->damage_lock);
426 
427 	queue_work(system_long_wq, &gdrm->work);
428 
429 	if (old_fb)
430 		drm_framebuffer_put(old_fb);
431 
432 	return 0;
433 }
434 
435 static void gud_fb_handle_damage(struct gud_device *gdrm, struct drm_framebuffer *fb,
436 				 const struct iosys_map *src, struct drm_rect *damage)
437 {
438 	int ret;
439 
440 	if (gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE)
441 		drm_rect_init(damage, 0, 0, fb->width, fb->height);
442 
443 	if (gud_async_flush) {
444 		ret = gud_fb_queue_damage(gdrm, fb, src, damage);
445 		if (ret != -ENOMEM)
446 			return;
447 	}
448 
449 	/* Imported buffers are assumed to be WriteCombined with uncached reads */
450 	gud_flush_damage(gdrm, fb, src, !fb->obj[0]->import_attach, damage);
451 }
452 
453 int gud_plane_atomic_check(struct drm_plane *plane,
454 			   struct drm_atomic_state *state)
455 {
456 	struct gud_device *gdrm = to_gud_device(plane->dev);
457 	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
458 	struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state, plane);
459 	struct drm_crtc *crtc = new_plane_state->crtc;
460 	struct drm_crtc_state *crtc_state;
461 	const struct drm_display_mode *mode;
462 	struct drm_framebuffer *old_fb = old_plane_state->fb;
463 	struct drm_connector_state *connector_state = NULL;
464 	struct drm_framebuffer *fb = new_plane_state->fb;
465 	const struct drm_format_info *format = fb->format;
466 	struct drm_connector *connector;
467 	unsigned int i, num_properties;
468 	struct gud_state_req *req;
469 	int idx, ret;
470 	size_t len;
471 
472 	if (drm_WARN_ON_ONCE(plane->dev, !fb))
473 		return -EINVAL;
474 
475 	if (drm_WARN_ON_ONCE(plane->dev, !crtc))
476 		return -EINVAL;
477 
478 	crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
479 
480 	mode = &crtc_state->mode;
481 
482 	ret = drm_atomic_helper_check_plane_state(new_plane_state, crtc_state,
483 						  DRM_PLANE_NO_SCALING,
484 						  DRM_PLANE_NO_SCALING,
485 						  false, false);
486 	if (ret)
487 		return ret;
488 
489 	if (!new_plane_state->visible)
490 		return 0;
491 
492 	if (old_plane_state->rotation != new_plane_state->rotation)
493 		crtc_state->mode_changed = true;
494 
495 	if (old_fb && old_fb->format != format)
496 		crtc_state->mode_changed = true;
497 
498 	if (!crtc_state->mode_changed && !crtc_state->connectors_changed)
499 		return 0;
500 
501 	/* Only one connector is supported */
502 	if (hweight32(crtc_state->connector_mask) != 1)
503 		return -EINVAL;
504 
505 	if (format->format == DRM_FORMAT_XRGB8888 && gdrm->xrgb8888_emulation_format)
506 		format = gdrm->xrgb8888_emulation_format;
507 
508 	for_each_new_connector_in_state(state, connector, connector_state, i) {
509 		if (connector_state->crtc)
510 			break;
511 	}
512 
513 	/*
514 	 * DRM_IOCTL_MODE_OBJ_SETPROPERTY on the rotation property will not have
515 	 * the connector included in the state.
516 	 */
517 	if (!connector_state) {
518 		struct drm_connector_list_iter conn_iter;
519 
520 		drm_connector_list_iter_begin(plane->dev, &conn_iter);
521 		drm_for_each_connector_iter(connector, &conn_iter) {
522 			if (connector->state->crtc) {
523 				connector_state = connector->state;
524 				break;
525 			}
526 		}
527 		drm_connector_list_iter_end(&conn_iter);
528 	}
529 
530 	if (WARN_ON_ONCE(!connector_state))
531 		return -ENOENT;
532 
533 	len = struct_size(req, properties,
534 			  size_add(GUD_PROPERTIES_MAX_NUM, GUD_CONNECTOR_PROPERTIES_MAX_NUM));
535 	req = kzalloc(len, GFP_KERNEL);
536 	if (!req)
537 		return -ENOMEM;
538 
539 	gud_from_display_mode(&req->mode, mode);
540 
541 	req->format = gud_from_fourcc(format->format);
542 	if (WARN_ON_ONCE(!req->format)) {
543 		ret = -EINVAL;
544 		goto out;
545 	}
546 
547 	req->connector = drm_connector_index(connector_state->connector);
548 
549 	ret = gud_connector_fill_properties(connector_state, req->properties);
550 	if (ret < 0)
551 		goto out;
552 
553 	num_properties = ret;
554 	for (i = 0; i < gdrm->num_properties; i++) {
555 		u16 prop = gdrm->properties[i];
556 		u64 val;
557 
558 		switch (prop) {
559 		case GUD_PROPERTY_ROTATION:
560 			/* DRM UAPI matches the protocol so use value directly */
561 			val = new_plane_state->rotation;
562 			break;
563 		default:
564 			WARN_ON_ONCE(1);
565 			ret = -EINVAL;
566 			goto out;
567 		}
568 
569 		req->properties[num_properties + i].prop = cpu_to_le16(prop);
570 		req->properties[num_properties + i].val = cpu_to_le64(val);
571 		num_properties++;
572 	}
573 
574 	if (drm_dev_enter(fb->dev, &idx)) {
575 		len = struct_size(req, properties, num_properties);
576 		ret = gud_usb_set(gdrm, GUD_REQ_SET_STATE_CHECK, 0, req, len);
577 		drm_dev_exit(idx);
578 	}  else {
579 		ret = -ENODEV;
580 	}
581 out:
582 	kfree(req);
583 
584 	return ret;
585 }
586 
587 void gud_plane_atomic_update(struct drm_plane *plane,
588 			     struct drm_atomic_state *atomic_state)
589 {
590 	struct drm_device *drm = plane->dev;
591 	struct gud_device *gdrm = to_gud_device(drm);
592 	struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(atomic_state, plane);
593 	struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(atomic_state, plane);
594 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(new_state);
595 	struct drm_framebuffer *fb = new_state->fb;
596 	struct drm_crtc *crtc = new_state->crtc;
597 	struct drm_rect damage;
598 	struct drm_atomic_helper_damage_iter iter;
599 	int ret, idx;
600 
601 	if (crtc->state->mode_changed || !crtc->state->enable) {
602 		cancel_work_sync(&gdrm->work);
603 		mutex_lock(&gdrm->damage_lock);
604 		if (gdrm->fb) {
605 			drm_framebuffer_put(gdrm->fb);
606 			gdrm->fb = NULL;
607 		}
608 		gud_clear_damage(gdrm);
609 		vfree(gdrm->shadow_buf);
610 		gdrm->shadow_buf = NULL;
611 		mutex_unlock(&gdrm->damage_lock);
612 	}
613 
614 	if (!drm_dev_enter(drm, &idx))
615 		return;
616 
617 	if (!old_state->fb)
618 		gud_usb_set_u8(gdrm, GUD_REQ_SET_CONTROLLER_ENABLE, 1);
619 
620 	if (fb && (crtc->state->mode_changed || crtc->state->connectors_changed))
621 		gud_usb_set(gdrm, GUD_REQ_SET_STATE_COMMIT, 0, NULL, 0);
622 
623 	if (crtc->state->active_changed)
624 		gud_usb_set_u8(gdrm, GUD_REQ_SET_DISPLAY_ENABLE, crtc->state->active);
625 
626 	if (!fb)
627 		goto ctrl_disable;
628 
629 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
630 	if (ret)
631 		goto ctrl_disable;
632 
633 	drm_atomic_helper_damage_iter_init(&iter, old_state, new_state);
634 	drm_atomic_for_each_plane_damage(&iter, &damage)
635 		gud_fb_handle_damage(gdrm, fb, &shadow_plane_state->data[0], &damage);
636 
637 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
638 
639 ctrl_disable:
640 	if (!crtc->state->enable)
641 		gud_usb_set_u8(gdrm, GUD_REQ_SET_CONTROLLER_ENABLE, 0);
642 
643 	drm_dev_exit(idx);
644 }
645