xref: /linux/drivers/gpu/drm/gud/gud_pipe.c (revision 9c93c0b44be36fd5267fb79ae33453f989fbe909)
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/drm_simple_kms_helper.h>
24 #include <drm/gud.h>
25 
26 #include "gud_internal.h"
27 
28 /*
29  * Some userspace rendering loops run all displays in the same loop.
30  * This means that a fast display will have to wait for a slow one.
31  * Such users might want to enable this module parameter.
32  */
33 static bool gud_async_flush;
34 module_param_named(async_flush, gud_async_flush, bool, 0644);
35 MODULE_PARM_DESC(async_flush, "Enable asynchronous flushing [default=0]");
36 
37 /*
38  * FIXME: The driver is probably broken on Big Endian machines.
39  * See discussion:
40  * https://lore.kernel.org/dri-devel/CAKb7UvihLX0hgBOP3VBG7O+atwZcUVCPVuBdfmDMpg0NjXe-cQ@mail.gmail.com/
41  */
42 
43 static bool gud_is_big_endian(void)
44 {
45 #if defined(__BIG_ENDIAN)
46 	return true;
47 #else
48 	return false;
49 #endif
50 }
51 
52 static size_t gud_xrgb8888_to_r124(u8 *dst, const struct drm_format_info *format,
53 				   void *src, struct drm_framebuffer *fb,
54 				   struct drm_rect *rect,
55 				   struct drm_format_conv_state *fmtcnv_state)
56 {
57 	unsigned int block_width = drm_format_info_block_width(format, 0);
58 	unsigned int bits_per_pixel = 8 / block_width;
59 	unsigned int x, y, width, height;
60 	u8 pix, *pix8, *block = dst; /* Assign to silence compiler warning */
61 	struct iosys_map dst_map, vmap;
62 	size_t len;
63 	void *buf;
64 
65 	WARN_ON_ONCE(format->char_per_block[0] != 1);
66 
67 	/* Start on a byte boundary */
68 	rect->x1 = ALIGN_DOWN(rect->x1, block_width);
69 	width = drm_rect_width(rect);
70 	height = drm_rect_height(rect);
71 	len = drm_format_info_min_pitch(format, 0, width) * height;
72 
73 	buf = kmalloc(width * height, GFP_KERNEL);
74 	if (!buf)
75 		return 0;
76 
77 	iosys_map_set_vaddr(&dst_map, buf);
78 	iosys_map_set_vaddr(&vmap, src);
79 	drm_fb_xrgb8888_to_gray8(&dst_map, NULL, &vmap, fb, rect, fmtcnv_state);
80 	pix8 = buf;
81 
82 	for (y = 0; y < height; y++) {
83 		for (x = 0; x < width; x++) {
84 			unsigned int pixpos = x % block_width; /* within byte from the left */
85 			unsigned int pixshift = (block_width - pixpos - 1) * bits_per_pixel;
86 
87 			if (!pixpos) {
88 				block = dst++;
89 				*block = 0;
90 			}
91 
92 			pix = (*pix8++) >> (8 - bits_per_pixel);
93 			*block |= pix << pixshift;
94 		}
95 	}
96 
97 	kfree(buf);
98 
99 	return len;
100 }
101 
102 static size_t gud_xrgb8888_to_color(u8 *dst, const struct drm_format_info *format,
103 				    void *src, struct drm_framebuffer *fb,
104 				    struct drm_rect *rect)
105 {
106 	unsigned int block_width = drm_format_info_block_width(format, 0);
107 	unsigned int bits_per_pixel = 8 / block_width;
108 	u8 r, g, b, pix, *block = dst; /* Assign to silence compiler warning */
109 	unsigned int x, y, width;
110 	__le32 *sbuf32;
111 	u32 pix32;
112 	size_t len;
113 
114 	/* Start on a byte boundary */
115 	rect->x1 = ALIGN_DOWN(rect->x1, block_width);
116 	width = drm_rect_width(rect);
117 	len = drm_format_info_min_pitch(format, 0, width) * drm_rect_height(rect);
118 
119 	for (y = rect->y1; y < rect->y2; y++) {
120 		sbuf32 = src + (y * fb->pitches[0]);
121 		sbuf32 += rect->x1;
122 
123 		for (x = 0; x < width; x++) {
124 			unsigned int pixpos = x % block_width; /* within byte from the left */
125 			unsigned int pixshift = (block_width - pixpos - 1) * bits_per_pixel;
126 
127 			if (!pixpos) {
128 				block = dst++;
129 				*block = 0;
130 			}
131 
132 			pix32 = le32_to_cpu(*sbuf32++);
133 			r = pix32 >> 16;
134 			g = pix32 >> 8;
135 			b = pix32;
136 
137 			switch (format->format) {
138 			case GUD_DRM_FORMAT_XRGB1111:
139 				pix = ((r >> 7) << 2) | ((g >> 7) << 1) | (b >> 7);
140 				break;
141 			default:
142 				WARN_ON_ONCE(1);
143 				return len;
144 			}
145 
146 			*block |= pix << pixshift;
147 		}
148 	}
149 
150 	return len;
151 }
152 
153 static int gud_prep_flush(struct gud_device *gdrm, struct drm_framebuffer *fb,
154 			  const struct iosys_map *src, bool cached_reads,
155 			  const struct drm_format_info *format, struct drm_rect *rect,
156 			  struct gud_set_buffer_req *req,
157 			  struct drm_format_conv_state *fmtcnv_state)
158 {
159 	u8 compression = gdrm->compression;
160 	struct iosys_map dst;
161 	void *vaddr, *buf;
162 	size_t pitch, len;
163 
164 	pitch = drm_format_info_min_pitch(format, 0, drm_rect_width(rect));
165 	len = pitch * drm_rect_height(rect);
166 	if (len > gdrm->bulk_len)
167 		return -E2BIG;
168 
169 	vaddr = src[0].vaddr;
170 retry:
171 	if (compression)
172 		buf = gdrm->compress_buf;
173 	else
174 		buf = gdrm->bulk_buf;
175 	iosys_map_set_vaddr(&dst, buf);
176 
177 	/*
178 	 * Imported buffers are assumed to be write-combined and thus uncached
179 	 * with slow reads (at least on ARM).
180 	 */
181 	if (format != fb->format) {
182 		if (format->format == GUD_DRM_FORMAT_R1) {
183 			len = gud_xrgb8888_to_r124(buf, format, vaddr, fb, rect, fmtcnv_state);
184 			if (!len)
185 				return -ENOMEM;
186 		} else if (format->format == DRM_FORMAT_R8) {
187 			drm_fb_xrgb8888_to_gray8(&dst, NULL, src, fb, rect, fmtcnv_state);
188 		} else if (format->format == DRM_FORMAT_RGB332) {
189 			drm_fb_xrgb8888_to_rgb332(&dst, NULL, src, fb, rect, fmtcnv_state);
190 		} else if (format->format == DRM_FORMAT_RGB565) {
191 			drm_fb_xrgb8888_to_rgb565(&dst, NULL, src, fb, rect, fmtcnv_state,
192 						  gud_is_big_endian());
193 		} else if (format->format == DRM_FORMAT_RGB888) {
194 			drm_fb_xrgb8888_to_rgb888(&dst, NULL, src, fb, rect, fmtcnv_state);
195 		} else {
196 			len = gud_xrgb8888_to_color(buf, format, vaddr, fb, rect);
197 		}
198 	} else if (gud_is_big_endian() && format->cpp[0] > 1) {
199 		drm_fb_swab(&dst, NULL, src, fb, rect, cached_reads, fmtcnv_state);
200 	} else if (compression && cached_reads && pitch == fb->pitches[0]) {
201 		/* can compress directly from the framebuffer */
202 		buf = vaddr + rect->y1 * pitch;
203 	} else {
204 		drm_fb_memcpy(&dst, NULL, src, fb, rect);
205 	}
206 
207 	memset(req, 0, sizeof(*req));
208 	req->x = cpu_to_le32(rect->x1);
209 	req->y = cpu_to_le32(rect->y1);
210 	req->width = cpu_to_le32(drm_rect_width(rect));
211 	req->height = cpu_to_le32(drm_rect_height(rect));
212 	req->length = cpu_to_le32(len);
213 
214 	if (compression & GUD_COMPRESSION_LZ4) {
215 		int complen;
216 
217 		complen = LZ4_compress_default(buf, gdrm->bulk_buf, len, len, gdrm->lz4_comp_mem);
218 		if (complen <= 0) {
219 			compression = 0;
220 			goto retry;
221 		}
222 
223 		req->compression = GUD_COMPRESSION_LZ4;
224 		req->compressed_length = cpu_to_le32(complen);
225 	}
226 
227 	return 0;
228 }
229 
230 struct gud_usb_bulk_context {
231 	struct timer_list timer;
232 	struct usb_sg_request sgr;
233 };
234 
235 static void gud_usb_bulk_timeout(struct timer_list *t)
236 {
237 	struct gud_usb_bulk_context *ctx = from_timer(ctx, t, timer);
238 
239 	usb_sg_cancel(&ctx->sgr);
240 }
241 
242 static int gud_usb_bulk(struct gud_device *gdrm, size_t len)
243 {
244 	struct gud_usb_bulk_context ctx;
245 	int ret;
246 
247 	ret = usb_sg_init(&ctx.sgr, gud_to_usb_device(gdrm), gdrm->bulk_pipe, 0,
248 			  gdrm->bulk_sgt.sgl, gdrm->bulk_sgt.nents, len, GFP_KERNEL);
249 	if (ret)
250 		return ret;
251 
252 	timer_setup_on_stack(&ctx.timer, gud_usb_bulk_timeout, 0);
253 	mod_timer(&ctx.timer, jiffies + msecs_to_jiffies(3000));
254 
255 	usb_sg_wait(&ctx.sgr);
256 
257 	if (!del_timer_sync(&ctx.timer))
258 		ret = -ETIMEDOUT;
259 	else if (ctx.sgr.status < 0)
260 		ret = ctx.sgr.status;
261 	else if (ctx.sgr.bytes != len)
262 		ret = -EIO;
263 
264 	destroy_timer_on_stack(&ctx.timer);
265 
266 	return ret;
267 }
268 
269 static int gud_flush_rect(struct gud_device *gdrm, struct drm_framebuffer *fb,
270 			  const struct iosys_map *src, bool cached_reads,
271 			  const struct drm_format_info *format, struct drm_rect *rect,
272 			  struct drm_format_conv_state *fmtcnv_state)
273 {
274 	struct gud_set_buffer_req req;
275 	size_t len, trlen;
276 	int ret;
277 
278 	drm_dbg(&gdrm->drm, "Flushing [FB:%d] " DRM_RECT_FMT "\n", fb->base.id, DRM_RECT_ARG(rect));
279 
280 	ret = gud_prep_flush(gdrm, fb, src, cached_reads, format, rect, &req, fmtcnv_state);
281 	if (ret)
282 		return ret;
283 
284 	len = le32_to_cpu(req.length);
285 
286 	if (req.compression)
287 		trlen = le32_to_cpu(req.compressed_length);
288 	else
289 		trlen = len;
290 
291 	gdrm->stats_length += len;
292 	/* Did it wrap around? */
293 	if (gdrm->stats_length <= len && gdrm->stats_actual_length) {
294 		gdrm->stats_length = len;
295 		gdrm->stats_actual_length = 0;
296 	}
297 	gdrm->stats_actual_length += trlen;
298 
299 	if (!(gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE) || gdrm->prev_flush_failed) {
300 		ret = gud_usb_set(gdrm, GUD_REQ_SET_BUFFER, 0, &req, sizeof(req));
301 		if (ret)
302 			return ret;
303 	}
304 
305 	ret = gud_usb_bulk(gdrm, trlen);
306 	if (ret)
307 		gdrm->stats_num_errors++;
308 
309 	return ret;
310 }
311 
312 void gud_clear_damage(struct gud_device *gdrm)
313 {
314 	gdrm->damage.x1 = INT_MAX;
315 	gdrm->damage.y1 = INT_MAX;
316 	gdrm->damage.x2 = 0;
317 	gdrm->damage.y2 = 0;
318 }
319 
320 static void gud_flush_damage(struct gud_device *gdrm, struct drm_framebuffer *fb,
321 			     const struct iosys_map *src, bool cached_reads,
322 			     struct drm_rect *damage)
323 {
324 	struct drm_format_conv_state fmtcnv_state = DRM_FORMAT_CONV_STATE_INIT;
325 	const struct drm_format_info *format;
326 	unsigned int i, lines;
327 	size_t pitch;
328 	int ret;
329 
330 	format = fb->format;
331 	if (format->format == DRM_FORMAT_XRGB8888 && gdrm->xrgb8888_emulation_format)
332 		format = gdrm->xrgb8888_emulation_format;
333 
334 	/* Split update if it's too big */
335 	pitch = drm_format_info_min_pitch(format, 0, drm_rect_width(damage));
336 	lines = drm_rect_height(damage);
337 
338 	if (gdrm->bulk_len < lines * pitch)
339 		lines = gdrm->bulk_len / pitch;
340 
341 	for (i = 0; i < DIV_ROUND_UP(drm_rect_height(damage), lines); i++) {
342 		struct drm_rect rect = *damage;
343 
344 		rect.y1 += i * lines;
345 		rect.y2 = min_t(u32, rect.y1 + lines, damage->y2);
346 
347 		ret = gud_flush_rect(gdrm, fb, src, cached_reads, format, &rect, &fmtcnv_state);
348 		if (ret) {
349 			if (ret != -ENODEV && ret != -ECONNRESET &&
350 			    ret != -ESHUTDOWN && ret != -EPROTO)
351 				dev_err_ratelimited(fb->dev->dev,
352 						    "Failed to flush framebuffer: error=%d\n", ret);
353 			gdrm->prev_flush_failed = true;
354 			break;
355 		}
356 	}
357 
358 	drm_format_conv_state_release(&fmtcnv_state);
359 }
360 
361 void gud_flush_work(struct work_struct *work)
362 {
363 	struct gud_device *gdrm = container_of(work, struct gud_device, work);
364 	struct iosys_map shadow_map;
365 	struct drm_framebuffer *fb;
366 	struct drm_rect damage;
367 	int idx;
368 
369 	if (!drm_dev_enter(&gdrm->drm, &idx))
370 		return;
371 
372 	mutex_lock(&gdrm->damage_lock);
373 	fb = gdrm->fb;
374 	gdrm->fb = NULL;
375 	iosys_map_set_vaddr(&shadow_map, gdrm->shadow_buf);
376 	damage = gdrm->damage;
377 	gud_clear_damage(gdrm);
378 	mutex_unlock(&gdrm->damage_lock);
379 
380 	if (!fb)
381 		goto out;
382 
383 	gud_flush_damage(gdrm, fb, &shadow_map, true, &damage);
384 
385 	drm_framebuffer_put(fb);
386 out:
387 	drm_dev_exit(idx);
388 }
389 
390 static int gud_fb_queue_damage(struct gud_device *gdrm, struct drm_framebuffer *fb,
391 			       const struct iosys_map *src, struct drm_rect *damage)
392 {
393 	struct drm_framebuffer *old_fb = NULL;
394 	struct iosys_map shadow_map;
395 
396 	mutex_lock(&gdrm->damage_lock);
397 
398 	if (!gdrm->shadow_buf) {
399 		gdrm->shadow_buf = vcalloc(fb->pitches[0], fb->height);
400 		if (!gdrm->shadow_buf) {
401 			mutex_unlock(&gdrm->damage_lock);
402 			return -ENOMEM;
403 		}
404 	}
405 
406 	iosys_map_set_vaddr(&shadow_map, gdrm->shadow_buf);
407 	iosys_map_incr(&shadow_map, drm_fb_clip_offset(fb->pitches[0], fb->format, damage));
408 	drm_fb_memcpy(&shadow_map, fb->pitches, src, fb, damage);
409 
410 	if (fb != gdrm->fb) {
411 		old_fb = gdrm->fb;
412 		drm_framebuffer_get(fb);
413 		gdrm->fb = fb;
414 	}
415 
416 	gdrm->damage.x1 = min(gdrm->damage.x1, damage->x1);
417 	gdrm->damage.y1 = min(gdrm->damage.y1, damage->y1);
418 	gdrm->damage.x2 = max(gdrm->damage.x2, damage->x2);
419 	gdrm->damage.y2 = max(gdrm->damage.y2, damage->y2);
420 
421 	mutex_unlock(&gdrm->damage_lock);
422 
423 	queue_work(system_long_wq, &gdrm->work);
424 
425 	if (old_fb)
426 		drm_framebuffer_put(old_fb);
427 
428 	return 0;
429 }
430 
431 static void gud_fb_handle_damage(struct gud_device *gdrm, struct drm_framebuffer *fb,
432 				 const struct iosys_map *src, struct drm_rect *damage)
433 {
434 	int ret;
435 
436 	if (gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE)
437 		drm_rect_init(damage, 0, 0, fb->width, fb->height);
438 
439 	if (gud_async_flush) {
440 		ret = gud_fb_queue_damage(gdrm, fb, src, damage);
441 		if (ret != -ENOMEM)
442 			return;
443 	}
444 
445 	/* Imported buffers are assumed to be WriteCombined with uncached reads */
446 	gud_flush_damage(gdrm, fb, src, !fb->obj[0]->import_attach, damage);
447 }
448 
449 int gud_pipe_check(struct drm_simple_display_pipe *pipe,
450 		   struct drm_plane_state *new_plane_state,
451 		   struct drm_crtc_state *new_crtc_state)
452 {
453 	struct gud_device *gdrm = to_gud_device(pipe->crtc.dev);
454 	struct drm_plane_state *old_plane_state = pipe->plane.state;
455 	const struct drm_display_mode *mode = &new_crtc_state->mode;
456 	struct drm_atomic_state *state = new_plane_state->state;
457 	struct drm_framebuffer *old_fb = old_plane_state->fb;
458 	struct drm_connector_state *connector_state = NULL;
459 	struct drm_framebuffer *fb = new_plane_state->fb;
460 	const struct drm_format_info *format = fb->format;
461 	struct drm_connector *connector;
462 	unsigned int i, num_properties;
463 	struct gud_state_req *req;
464 	int idx, ret;
465 	size_t len;
466 
467 	if (WARN_ON_ONCE(!fb))
468 		return -EINVAL;
469 
470 	if (old_plane_state->rotation != new_plane_state->rotation)
471 		new_crtc_state->mode_changed = true;
472 
473 	if (old_fb && old_fb->format != format)
474 		new_crtc_state->mode_changed = true;
475 
476 	if (!new_crtc_state->mode_changed && !new_crtc_state->connectors_changed)
477 		return 0;
478 
479 	/* Only one connector is supported */
480 	if (hweight32(new_crtc_state->connector_mask) != 1)
481 		return -EINVAL;
482 
483 	if (format->format == DRM_FORMAT_XRGB8888 && gdrm->xrgb8888_emulation_format)
484 		format = gdrm->xrgb8888_emulation_format;
485 
486 	for_each_new_connector_in_state(state, connector, connector_state, i) {
487 		if (connector_state->crtc)
488 			break;
489 	}
490 
491 	/*
492 	 * DRM_IOCTL_MODE_OBJ_SETPROPERTY on the rotation property will not have
493 	 * the connector included in the state.
494 	 */
495 	if (!connector_state) {
496 		struct drm_connector_list_iter conn_iter;
497 
498 		drm_connector_list_iter_begin(pipe->crtc.dev, &conn_iter);
499 		drm_for_each_connector_iter(connector, &conn_iter) {
500 			if (connector->state->crtc) {
501 				connector_state = connector->state;
502 				break;
503 			}
504 		}
505 		drm_connector_list_iter_end(&conn_iter);
506 	}
507 
508 	if (WARN_ON_ONCE(!connector_state))
509 		return -ENOENT;
510 
511 	len = struct_size(req, properties,
512 			  size_add(GUD_PROPERTIES_MAX_NUM, GUD_CONNECTOR_PROPERTIES_MAX_NUM));
513 	req = kzalloc(len, GFP_KERNEL);
514 	if (!req)
515 		return -ENOMEM;
516 
517 	gud_from_display_mode(&req->mode, mode);
518 
519 	req->format = gud_from_fourcc(format->format);
520 	if (WARN_ON_ONCE(!req->format)) {
521 		ret = -EINVAL;
522 		goto out;
523 	}
524 
525 	req->connector = drm_connector_index(connector_state->connector);
526 
527 	ret = gud_connector_fill_properties(connector_state, req->properties);
528 	if (ret < 0)
529 		goto out;
530 
531 	num_properties = ret;
532 	for (i = 0; i < gdrm->num_properties; i++) {
533 		u16 prop = gdrm->properties[i];
534 		u64 val;
535 
536 		switch (prop) {
537 		case GUD_PROPERTY_ROTATION:
538 			/* DRM UAPI matches the protocol so use value directly */
539 			val = new_plane_state->rotation;
540 			break;
541 		default:
542 			WARN_ON_ONCE(1);
543 			ret = -EINVAL;
544 			goto out;
545 		}
546 
547 		req->properties[num_properties + i].prop = cpu_to_le16(prop);
548 		req->properties[num_properties + i].val = cpu_to_le64(val);
549 		num_properties++;
550 	}
551 
552 	if (drm_dev_enter(fb->dev, &idx)) {
553 		len = struct_size(req, properties, num_properties);
554 		ret = gud_usb_set(gdrm, GUD_REQ_SET_STATE_CHECK, 0, req, len);
555 		drm_dev_exit(idx);
556 	}  else {
557 		ret = -ENODEV;
558 	}
559 out:
560 	kfree(req);
561 
562 	return ret;
563 }
564 
565 void gud_pipe_update(struct drm_simple_display_pipe *pipe,
566 		     struct drm_plane_state *old_state)
567 {
568 	struct drm_device *drm = pipe->crtc.dev;
569 	struct gud_device *gdrm = to_gud_device(drm);
570 	struct drm_plane_state *state = pipe->plane.state;
571 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
572 	struct drm_framebuffer *fb = state->fb;
573 	struct drm_crtc *crtc = &pipe->crtc;
574 	struct drm_rect damage;
575 	int ret, idx;
576 
577 	if (crtc->state->mode_changed || !crtc->state->enable) {
578 		cancel_work_sync(&gdrm->work);
579 		mutex_lock(&gdrm->damage_lock);
580 		if (gdrm->fb) {
581 			drm_framebuffer_put(gdrm->fb);
582 			gdrm->fb = NULL;
583 		}
584 		gud_clear_damage(gdrm);
585 		vfree(gdrm->shadow_buf);
586 		gdrm->shadow_buf = NULL;
587 		mutex_unlock(&gdrm->damage_lock);
588 	}
589 
590 	if (!drm_dev_enter(drm, &idx))
591 		return;
592 
593 	if (!old_state->fb)
594 		gud_usb_set_u8(gdrm, GUD_REQ_SET_CONTROLLER_ENABLE, 1);
595 
596 	if (fb && (crtc->state->mode_changed || crtc->state->connectors_changed))
597 		gud_usb_set(gdrm, GUD_REQ_SET_STATE_COMMIT, 0, NULL, 0);
598 
599 	if (crtc->state->active_changed)
600 		gud_usb_set_u8(gdrm, GUD_REQ_SET_DISPLAY_ENABLE, crtc->state->active);
601 
602 	if (!fb)
603 		goto ctrl_disable;
604 
605 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
606 	if (ret)
607 		goto ctrl_disable;
608 
609 	if (drm_atomic_helper_damage_merged(old_state, state, &damage))
610 		gud_fb_handle_damage(gdrm, fb, &shadow_plane_state->data[0], &damage);
611 
612 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
613 
614 ctrl_disable:
615 	if (!crtc->state->enable)
616 		gud_usb_set_u8(gdrm, GUD_REQ_SET_CONTROLLER_ENABLE, 0);
617 
618 	drm_dev_exit(idx);
619 }
620