xref: /linux/drivers/gpu/drm/udl/udl_modeset.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 Red Hat
4  *
5  * based in parts on udlfb.c:
6  * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
7  * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
8  * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
9  */
10 
11 #include <linux/bitfield.h>
12 
13 #include <drm/drm_atomic.h>
14 #include <drm/drm_atomic_helper.h>
15 #include <drm/drm_crtc_helper.h>
16 #include <drm/drm_damage_helper.h>
17 #include <drm/drm_drv.h>
18 #include <drm/drm_edid.h>
19 #include <drm/drm_fourcc.h>
20 #include <drm/drm_gem_atomic_helper.h>
21 #include <drm/drm_gem_framebuffer_helper.h>
22 #include <drm/drm_gem_shmem_helper.h>
23 #include <drm/drm_modeset_helper_vtables.h>
24 #include <drm/drm_plane_helper.h>
25 #include <drm/drm_probe_helper.h>
26 #include <drm/drm_vblank.h>
27 
28 #include "udl_drv.h"
29 #include "udl_proto.h"
30 
31 /*
32  * All DisplayLink bulk operations start with 0xaf (UDL_MSG_BULK), followed by
33  * a specific command code. All operations are written to a command buffer, which
34  * the driver sends to the device.
35  */
36 static char *udl_set_register(char *buf, u8 reg, u8 val)
37 {
38 	*buf++ = UDL_MSG_BULK;
39 	*buf++ = UDL_CMD_WRITEREG;
40 	*buf++ = reg;
41 	*buf++ = val;
42 
43 	return buf;
44 }
45 
46 static char *udl_vidreg_lock(char *buf)
47 {
48 	return udl_set_register(buf, UDL_REG_VIDREG, UDL_VIDREG_LOCK);
49 }
50 
51 static char *udl_vidreg_unlock(char *buf)
52 {
53 	return udl_set_register(buf, UDL_REG_VIDREG, UDL_VIDREG_UNLOCK);
54 }
55 
56 static char *udl_set_blank_mode(char *buf, u8 mode)
57 {
58 	return udl_set_register(buf, UDL_REG_BLANKMODE, mode);
59 }
60 
61 static char *udl_set_color_depth(char *buf, u8 selection)
62 {
63 	return udl_set_register(buf, UDL_REG_COLORDEPTH, selection);
64 }
65 
66 static char *udl_set_base16bpp(char *buf, u32 base)
67 {
68 	/* the base pointer is 24 bits wide, 0x20 is hi byte. */
69 	u8 reg20 = FIELD_GET(UDL_BASE_ADDR2_MASK, base);
70 	u8 reg21 = FIELD_GET(UDL_BASE_ADDR1_MASK, base);
71 	u8 reg22 = FIELD_GET(UDL_BASE_ADDR0_MASK, base);
72 
73 	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR2, reg20);
74 	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR1, reg21);
75 	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR0, reg22);
76 
77 	return buf;
78 }
79 
80 /*
81  * DisplayLink HW has separate 16bpp and 8bpp framebuffers.
82  * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer
83  */
84 static char *udl_set_base8bpp(char *buf, u32 base)
85 {
86 	/* the base pointer is 24 bits wide, 0x26 is hi byte. */
87 	u8 reg26 = FIELD_GET(UDL_BASE_ADDR2_MASK, base);
88 	u8 reg27 = FIELD_GET(UDL_BASE_ADDR1_MASK, base);
89 	u8 reg28 = FIELD_GET(UDL_BASE_ADDR0_MASK, base);
90 
91 	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR2, reg26);
92 	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR1, reg27);
93 	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR0, reg28);
94 
95 	return buf;
96 }
97 
98 static char *udl_set_register_16(char *wrptr, u8 reg, u16 value)
99 {
100 	wrptr = udl_set_register(wrptr, reg, value >> 8);
101 	return udl_set_register(wrptr, reg+1, value);
102 }
103 
104 /*
105  * This is kind of weird because the controller takes some
106  * register values in a different byte order than other registers.
107  */
108 static char *udl_set_register_16be(char *wrptr, u8 reg, u16 value)
109 {
110 	wrptr = udl_set_register(wrptr, reg, value);
111 	return udl_set_register(wrptr, reg+1, value >> 8);
112 }
113 
114 /*
115  * LFSR is linear feedback shift register. The reason we have this is
116  * because the display controller needs to minimize the clock depth of
117  * various counters used in the display path. So this code reverses the
118  * provided value into the lfsr16 value by counting backwards to get
119  * the value that needs to be set in the hardware comparator to get the
120  * same actual count. This makes sense once you read above a couple of
121  * times and think about it from a hardware perspective.
122  */
123 static u16 udl_lfsr16(u16 actual_count)
124 {
125 	u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */
126 
127 	while (actual_count--) {
128 		lv =	 ((lv << 1) |
129 			(((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1))
130 			& 0xFFFF;
131 	}
132 
133 	return (u16) lv;
134 }
135 
136 /*
137  * This does LFSR conversion on the value that is to be written.
138  * See LFSR explanation above for more detail.
139  */
140 static char *udl_set_register_lfsr16(char *wrptr, u8 reg, u16 value)
141 {
142 	return udl_set_register_16(wrptr, reg, udl_lfsr16(value));
143 }
144 
145 /*
146  * Takes a DRM display mode and converts it into the DisplayLink
147  * equivalent register commands.
148  */
149 static char *udl_set_display_mode(char *buf, struct drm_display_mode *mode)
150 {
151 	u16 reg01 = mode->crtc_htotal - mode->crtc_hsync_start;
152 	u16 reg03 = reg01 + mode->crtc_hdisplay;
153 	u16 reg05 = mode->crtc_vtotal - mode->crtc_vsync_start;
154 	u16 reg07 = reg05 + mode->crtc_vdisplay;
155 	u16 reg09 = mode->crtc_htotal - 1;
156 	u16 reg0b = 1; /* libdlo hardcodes hsync start to 1 */
157 	u16 reg0d = mode->crtc_hsync_end - mode->crtc_hsync_start + 1;
158 	u16 reg0f = mode->hdisplay;
159 	u16 reg11 = mode->crtc_vtotal;
160 	u16 reg13 = 0; /* libdlo hardcodes vsync start to 0 */
161 	u16 reg15 = mode->crtc_vsync_end - mode->crtc_vsync_start;
162 	u16 reg17 = mode->crtc_vdisplay;
163 	u16 reg1b = mode->clock / 5;
164 
165 	buf = udl_set_register_lfsr16(buf, UDL_REG_XDISPLAYSTART, reg01);
166 	buf = udl_set_register_lfsr16(buf, UDL_REG_XDISPLAYEND, reg03);
167 	buf = udl_set_register_lfsr16(buf, UDL_REG_YDISPLAYSTART, reg05);
168 	buf = udl_set_register_lfsr16(buf, UDL_REG_YDISPLAYEND, reg07);
169 	buf = udl_set_register_lfsr16(buf, UDL_REG_XENDCOUNT, reg09);
170 	buf = udl_set_register_lfsr16(buf, UDL_REG_HSYNCSTART, reg0b);
171 	buf = udl_set_register_lfsr16(buf, UDL_REG_HSYNCEND, reg0d);
172 	buf = udl_set_register_16(buf, UDL_REG_HPIXELS, reg0f);
173 	buf = udl_set_register_lfsr16(buf, UDL_REG_YENDCOUNT, reg11);
174 	buf = udl_set_register_lfsr16(buf, UDL_REG_VSYNCSTART, reg13);
175 	buf = udl_set_register_lfsr16(buf, UDL_REG_VSYNCEND, reg15);
176 	buf = udl_set_register_16(buf, UDL_REG_VPIXELS, reg17);
177 	buf = udl_set_register_16be(buf, UDL_REG_PIXELCLOCK5KHZ, reg1b);
178 
179 	return buf;
180 }
181 
182 static char *udl_dummy_render(char *wrptr)
183 {
184 	*wrptr++ = UDL_MSG_BULK;
185 	*wrptr++ = UDL_CMD_WRITECOPY16;
186 	*wrptr++ = 0x00; /* from addr */
187 	*wrptr++ = 0x00;
188 	*wrptr++ = 0x00;
189 	*wrptr++ = 0x01; /* one pixel */
190 	*wrptr++ = 0x00; /* to address */
191 	*wrptr++ = 0x00;
192 	*wrptr++ = 0x00;
193 	return wrptr;
194 }
195 
196 static long udl_log_cpp(unsigned int cpp)
197 {
198 	if (WARN_ON(!is_power_of_2(cpp)))
199 		return -EINVAL;
200 	return __ffs(cpp);
201 }
202 
203 static int udl_handle_damage(struct drm_framebuffer *fb,
204 			     const struct iosys_map *map,
205 			     const struct drm_rect *clip)
206 {
207 	struct drm_device *dev = fb->dev;
208 	void *vaddr = map->vaddr; /* TODO: Use mapping abstraction properly */
209 	int i, ret;
210 	char *cmd;
211 	struct urb *urb;
212 	int log_bpp;
213 
214 	ret = udl_log_cpp(fb->format->cpp[0]);
215 	if (ret < 0)
216 		return ret;
217 	log_bpp = ret;
218 
219 	urb = udl_get_urb(dev);
220 	if (!urb)
221 		return -ENOMEM;
222 	cmd = urb->transfer_buffer;
223 
224 	for (i = clip->y1; i < clip->y2; i++) {
225 		const int line_offset = fb->pitches[0] * i;
226 		const int byte_offset = line_offset + (clip->x1 << log_bpp);
227 		const int dev_byte_offset = (fb->width * i + clip->x1) << log_bpp;
228 		const int byte_width = drm_rect_width(clip) << log_bpp;
229 		ret = udl_render_hline(dev, log_bpp, &urb, (char *)vaddr,
230 				       &cmd, byte_offset, dev_byte_offset,
231 				       byte_width);
232 		if (ret)
233 			return ret;
234 	}
235 
236 	if (cmd > (char *)urb->transfer_buffer) {
237 		/* Send partial buffer remaining before exiting */
238 		int len;
239 		if (cmd < (char *)urb->transfer_buffer + urb->transfer_buffer_length)
240 			*cmd++ = UDL_MSG_BULK;
241 		len = cmd - (char *)urb->transfer_buffer;
242 		ret = udl_submit_urb(dev, urb, len);
243 	} else {
244 		udl_urb_completion(urb);
245 	}
246 
247 	return 0;
248 }
249 
250 /*
251  * Primary plane
252  */
253 
254 static const uint32_t udl_primary_plane_formats[] = {
255 	DRM_FORMAT_RGB565,
256 	DRM_FORMAT_XRGB8888,
257 };
258 
259 static const uint64_t udl_primary_plane_fmtmods[] = {
260 	DRM_FORMAT_MOD_LINEAR,
261 	DRM_FORMAT_MOD_INVALID
262 };
263 
264 static void udl_primary_plane_helper_atomic_update(struct drm_plane *plane,
265 						   struct drm_atomic_state *state)
266 {
267 	struct drm_device *dev = plane->dev;
268 	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
269 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
270 	struct drm_framebuffer *fb = plane_state->fb;
271 	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
272 	struct drm_atomic_helper_damage_iter iter;
273 	struct drm_rect damage;
274 	int ret, idx;
275 
276 	if (!fb)
277 		return; /* no framebuffer; plane is disabled */
278 
279 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
280 	if (ret)
281 		return;
282 
283 	if (!drm_dev_enter(dev, &idx))
284 		goto out_drm_gem_fb_end_cpu_access;
285 
286 	drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);
287 	drm_atomic_for_each_plane_damage(&iter, &damage) {
288 		udl_handle_damage(fb, &shadow_plane_state->data[0], &damage);
289 	}
290 
291 	drm_dev_exit(idx);
292 
293 out_drm_gem_fb_end_cpu_access:
294 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
295 }
296 
297 static const struct drm_plane_helper_funcs udl_primary_plane_helper_funcs = {
298 	DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
299 	.atomic_check = drm_plane_helper_atomic_check,
300 	.atomic_update = udl_primary_plane_helper_atomic_update,
301 };
302 
303 static const struct drm_plane_funcs udl_primary_plane_funcs = {
304 	.update_plane = drm_atomic_helper_update_plane,
305 	.disable_plane = drm_atomic_helper_disable_plane,
306 	.destroy = drm_plane_cleanup,
307 	DRM_GEM_SHADOW_PLANE_FUNCS,
308 };
309 
310 /*
311  * CRTC
312  */
313 
314 static void udl_crtc_helper_atomic_enable(struct drm_crtc *crtc, struct drm_atomic_state *state)
315 {
316 	struct drm_device *dev = crtc->dev;
317 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
318 	struct drm_display_mode *mode = &crtc_state->mode;
319 	struct urb *urb;
320 	char *buf;
321 	int idx;
322 
323 	if (!drm_dev_enter(dev, &idx))
324 		return;
325 
326 	urb = udl_get_urb(dev);
327 	if (!urb)
328 		goto out;
329 
330 	buf = (char *)urb->transfer_buffer;
331 	buf = udl_vidreg_lock(buf);
332 	buf = udl_set_color_depth(buf, UDL_COLORDEPTH_16BPP);
333 	/* set base for 16bpp segment to 0 */
334 	buf = udl_set_base16bpp(buf, 0);
335 	/* set base for 8bpp segment to end of fb */
336 	buf = udl_set_base8bpp(buf, 2 * mode->vdisplay * mode->hdisplay);
337 	buf = udl_set_display_mode(buf, mode);
338 	buf = udl_set_blank_mode(buf, UDL_BLANKMODE_ON);
339 	buf = udl_vidreg_unlock(buf);
340 	buf = udl_dummy_render(buf);
341 
342 	udl_submit_urb(dev, urb, buf - (char *)urb->transfer_buffer);
343 
344 out:
345 	drm_dev_exit(idx);
346 }
347 
348 static void udl_crtc_helper_atomic_disable(struct drm_crtc *crtc, struct drm_atomic_state *state)
349 {
350 	struct drm_device *dev = crtc->dev;
351 	struct urb *urb;
352 	char *buf;
353 	int idx;
354 
355 	if (!drm_dev_enter(dev, &idx))
356 		return;
357 
358 	urb = udl_get_urb(dev);
359 	if (!urb)
360 		goto out;
361 
362 	buf = (char *)urb->transfer_buffer;
363 	buf = udl_vidreg_lock(buf);
364 	buf = udl_set_blank_mode(buf, UDL_BLANKMODE_POWERDOWN);
365 	buf = udl_vidreg_unlock(buf);
366 	buf = udl_dummy_render(buf);
367 
368 	udl_submit_urb(dev, urb, buf - (char *)urb->transfer_buffer);
369 
370 out:
371 	drm_dev_exit(idx);
372 }
373 
374 static const struct drm_crtc_helper_funcs udl_crtc_helper_funcs = {
375 	.atomic_check = drm_crtc_helper_atomic_check,
376 	.atomic_enable = udl_crtc_helper_atomic_enable,
377 	.atomic_disable = udl_crtc_helper_atomic_disable,
378 };
379 
380 static const struct drm_crtc_funcs udl_crtc_funcs = {
381 	.reset = drm_atomic_helper_crtc_reset,
382 	.destroy = drm_crtc_cleanup,
383 	.set_config = drm_atomic_helper_set_config,
384 	.page_flip = drm_atomic_helper_page_flip,
385 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
386 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
387 };
388 
389 /*
390  * Encoder
391  */
392 
393 static const struct drm_encoder_funcs udl_encoder_funcs = {
394 	.destroy = drm_encoder_cleanup,
395 };
396 
397 /*
398  * Connector
399  */
400 
401 static int udl_connector_helper_get_modes(struct drm_connector *connector)
402 {
403 	struct udl_connector *udl_connector = to_udl_connector(connector);
404 
405 	drm_connector_update_edid_property(connector, udl_connector->edid);
406 	if (udl_connector->edid)
407 		return drm_add_edid_modes(connector, udl_connector->edid);
408 
409 	return 0;
410 }
411 
412 static const struct drm_connector_helper_funcs udl_connector_helper_funcs = {
413 	.get_modes = udl_connector_helper_get_modes,
414 };
415 
416 static int udl_get_edid_block(void *data, u8 *buf, unsigned int block, size_t len)
417 {
418 	struct udl_device *udl = data;
419 	struct drm_device *dev = &udl->drm;
420 	struct usb_device *udev = udl_to_usb_device(udl);
421 	u8 *read_buff;
422 	int ret;
423 	size_t i;
424 
425 	read_buff = kmalloc(2, GFP_KERNEL);
426 	if (!read_buff)
427 		return -ENOMEM;
428 
429 	for (i = 0; i < len; i++) {
430 		int bval = (i + block * EDID_LENGTH) << 8;
431 
432 		ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
433 				      0x02, (0x80 | (0x02 << 5)), bval,
434 				      0xA1, read_buff, 2, USB_CTRL_GET_TIMEOUT);
435 		if (ret < 0) {
436 			drm_err(dev, "Read EDID byte %zu failed err %x\n", i, ret);
437 			goto err_kfree;
438 		} else if (ret < 1) {
439 			ret = -EIO;
440 			drm_err(dev, "Read EDID byte %zu failed\n", i);
441 			goto err_kfree;
442 		}
443 
444 		buf[i] = read_buff[1];
445 	}
446 
447 	kfree(read_buff);
448 
449 	return 0;
450 
451 err_kfree:
452 	kfree(read_buff);
453 	return ret;
454 }
455 
456 static enum drm_connector_status udl_connector_detect(struct drm_connector *connector, bool force)
457 {
458 	struct drm_device *dev = connector->dev;
459 	struct udl_device *udl = to_udl(dev);
460 	struct udl_connector *udl_connector = to_udl_connector(connector);
461 	enum drm_connector_status status = connector_status_disconnected;
462 	int idx;
463 
464 	/* cleanup previous EDID */
465 	kfree(udl_connector->edid);
466 	udl_connector->edid = NULL;
467 
468 	if (!drm_dev_enter(dev, &idx))
469 		return connector_status_disconnected;
470 
471 	udl_connector->edid = drm_do_get_edid(connector, udl_get_edid_block, udl);
472 	if (udl_connector->edid)
473 		status = connector_status_connected;
474 
475 	drm_dev_exit(idx);
476 
477 	return status;
478 }
479 
480 static void udl_connector_destroy(struct drm_connector *connector)
481 {
482 	struct udl_connector *udl_connector = to_udl_connector(connector);
483 
484 	drm_connector_cleanup(connector);
485 	kfree(udl_connector->edid);
486 	kfree(udl_connector);
487 }
488 
489 static const struct drm_connector_funcs udl_connector_funcs = {
490 	.reset = drm_atomic_helper_connector_reset,
491 	.detect = udl_connector_detect,
492 	.fill_modes = drm_helper_probe_single_connector_modes,
493 	.destroy = udl_connector_destroy,
494 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
495 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
496 };
497 
498 struct drm_connector *udl_connector_init(struct drm_device *dev)
499 {
500 	struct udl_connector *udl_connector;
501 	struct drm_connector *connector;
502 	int ret;
503 
504 	udl_connector = kzalloc(sizeof(*udl_connector), GFP_KERNEL);
505 	if (!udl_connector)
506 		return ERR_PTR(-ENOMEM);
507 
508 	connector = &udl_connector->connector;
509 	ret = drm_connector_init(dev, connector, &udl_connector_funcs, DRM_MODE_CONNECTOR_VGA);
510 	if (ret)
511 		goto err_kfree;
512 
513 	drm_connector_helper_add(connector, &udl_connector_helper_funcs);
514 
515 	connector->polled = DRM_CONNECTOR_POLL_HPD |
516 			    DRM_CONNECTOR_POLL_CONNECT |
517 			    DRM_CONNECTOR_POLL_DISCONNECT;
518 
519 	return connector;
520 
521 err_kfree:
522 	kfree(udl_connector);
523 	return ERR_PTR(ret);
524 }
525 
526 /*
527  * Modesetting
528  */
529 
530 static enum drm_mode_status udl_mode_config_mode_valid(struct drm_device *dev,
531 						       const struct drm_display_mode *mode)
532 {
533 	struct udl_device *udl = to_udl(dev);
534 
535 	if (udl->sku_pixel_limit) {
536 		if (mode->vdisplay * mode->hdisplay > udl->sku_pixel_limit)
537 			return MODE_MEM;
538 	}
539 
540 	return MODE_OK;
541 }
542 
543 static const struct drm_mode_config_funcs udl_mode_config_funcs = {
544 	.fb_create = drm_gem_fb_create_with_dirty,
545 	.mode_valid = udl_mode_config_mode_valid,
546 	.atomic_check  = drm_atomic_helper_check,
547 	.atomic_commit = drm_atomic_helper_commit,
548 };
549 
550 int udl_modeset_init(struct drm_device *dev)
551 {
552 	struct udl_device *udl = to_udl(dev);
553 	struct drm_plane *primary_plane;
554 	struct drm_crtc *crtc;
555 	struct drm_encoder *encoder;
556 	struct drm_connector *connector;
557 	int ret;
558 
559 	ret = drmm_mode_config_init(dev);
560 	if (ret)
561 		return ret;
562 
563 	dev->mode_config.min_width = 640;
564 	dev->mode_config.min_height = 480;
565 	dev->mode_config.max_width = 2048;
566 	dev->mode_config.max_height = 2048;
567 	dev->mode_config.preferred_depth = 16;
568 	dev->mode_config.funcs = &udl_mode_config_funcs;
569 
570 	primary_plane = &udl->primary_plane;
571 	ret = drm_universal_plane_init(dev, primary_plane, 0,
572 				       &udl_primary_plane_funcs,
573 				       udl_primary_plane_formats,
574 				       ARRAY_SIZE(udl_primary_plane_formats),
575 				       udl_primary_plane_fmtmods,
576 				       DRM_PLANE_TYPE_PRIMARY, NULL);
577 	if (ret)
578 		return ret;
579 	drm_plane_helper_add(primary_plane, &udl_primary_plane_helper_funcs);
580 	drm_plane_enable_fb_damage_clips(primary_plane);
581 
582 	crtc = &udl->crtc;
583 	ret = drm_crtc_init_with_planes(dev, crtc, primary_plane, NULL,
584 					&udl_crtc_funcs, NULL);
585 	if (ret)
586 		return ret;
587 	drm_crtc_helper_add(crtc, &udl_crtc_helper_funcs);
588 
589 	encoder = &udl->encoder;
590 	ret = drm_encoder_init(dev, encoder, &udl_encoder_funcs, DRM_MODE_ENCODER_DAC, NULL);
591 	if (ret)
592 		return ret;
593 	encoder->possible_crtcs = drm_crtc_mask(crtc);
594 
595 	connector = udl_connector_init(dev);
596 	if (IS_ERR(connector))
597 		return PTR_ERR(connector);
598 	ret = drm_connector_attach_encoder(connector, encoder);
599 	if (ret)
600 		return ret;
601 
602 	drm_mode_config_reset(dev);
603 
604 	return 0;
605 }
606