xref: /linux/drivers/gpu/drm/udl/udl_modeset.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
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_probe_helper.h>
25 #include <drm/drm_vblank.h>
26 
27 #include "udl_drv.h"
28 #include "udl_proto.h"
29 
30 /*
31  * All DisplayLink bulk operations start with 0xaf (UDL_MSG_BULK), followed by
32  * a specific command code. All operations are written to a command buffer, which
33  * the driver sends to the device.
34  */
35 static char *udl_set_register(char *buf, u8 reg, u8 val)
36 {
37 	*buf++ = UDL_MSG_BULK;
38 	*buf++ = UDL_CMD_WRITEREG;
39 	*buf++ = reg;
40 	*buf++ = val;
41 
42 	return buf;
43 }
44 
45 static char *udl_vidreg_lock(char *buf)
46 {
47 	return udl_set_register(buf, UDL_REG_VIDREG, UDL_VIDREG_LOCK);
48 }
49 
50 static char *udl_vidreg_unlock(char *buf)
51 {
52 	return udl_set_register(buf, UDL_REG_VIDREG, UDL_VIDREG_UNLOCK);
53 }
54 
55 static char *udl_set_blank_mode(char *buf, u8 mode)
56 {
57 	return udl_set_register(buf, UDL_REG_BLANKMODE, mode);
58 }
59 
60 static char *udl_set_color_depth(char *buf, u8 selection)
61 {
62 	return udl_set_register(buf, UDL_REG_COLORDEPTH, selection);
63 }
64 
65 static char *udl_set_base16bpp(char *buf, u32 base)
66 {
67 	/* the base pointer is 24 bits wide, 0x20 is hi byte. */
68 	u8 reg20 = FIELD_GET(UDL_BASE_ADDR2_MASK, base);
69 	u8 reg21 = FIELD_GET(UDL_BASE_ADDR1_MASK, base);
70 	u8 reg22 = FIELD_GET(UDL_BASE_ADDR0_MASK, base);
71 
72 	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR2, reg20);
73 	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR1, reg21);
74 	buf = udl_set_register(buf, UDL_REG_BASE16BPP_ADDR0, reg22);
75 
76 	return buf;
77 }
78 
79 /*
80  * DisplayLink HW has separate 16bpp and 8bpp framebuffers.
81  * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer
82  */
83 static char *udl_set_base8bpp(char *buf, u32 base)
84 {
85 	/* the base pointer is 24 bits wide, 0x26 is hi byte. */
86 	u8 reg26 = FIELD_GET(UDL_BASE_ADDR2_MASK, base);
87 	u8 reg27 = FIELD_GET(UDL_BASE_ADDR1_MASK, base);
88 	u8 reg28 = FIELD_GET(UDL_BASE_ADDR0_MASK, base);
89 
90 	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR2, reg26);
91 	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR1, reg27);
92 	buf = udl_set_register(buf, UDL_REG_BASE8BPP_ADDR0, reg28);
93 
94 	return buf;
95 }
96 
97 static char *udl_set_register_16(char *wrptr, u8 reg, u16 value)
98 {
99 	wrptr = udl_set_register(wrptr, reg, value >> 8);
100 	return udl_set_register(wrptr, reg+1, value);
101 }
102 
103 /*
104  * This is kind of weird because the controller takes some
105  * register values in a different byte order than other registers.
106  */
107 static char *udl_set_register_16be(char *wrptr, u8 reg, u16 value)
108 {
109 	wrptr = udl_set_register(wrptr, reg, value);
110 	return udl_set_register(wrptr, reg+1, value >> 8);
111 }
112 
113 /*
114  * LFSR is linear feedback shift register. The reason we have this is
115  * because the display controller needs to minimize the clock depth of
116  * various counters used in the display path. So this code reverses the
117  * provided value into the lfsr16 value by counting backwards to get
118  * the value that needs to be set in the hardware comparator to get the
119  * same actual count. This makes sense once you read above a couple of
120  * times and think about it from a hardware perspective.
121  */
122 static u16 udl_lfsr16(u16 actual_count)
123 {
124 	u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */
125 
126 	while (actual_count--) {
127 		lv =	 ((lv << 1) |
128 			(((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1))
129 			& 0xFFFF;
130 	}
131 
132 	return (u16) lv;
133 }
134 
135 /*
136  * This does LFSR conversion on the value that is to be written.
137  * See LFSR explanation above for more detail.
138  */
139 static char *udl_set_register_lfsr16(char *wrptr, u8 reg, u16 value)
140 {
141 	return udl_set_register_16(wrptr, reg, udl_lfsr16(value));
142 }
143 
144 /*
145  * Takes a DRM display mode and converts it into the DisplayLink
146  * equivalent register commands.
147  */
148 static char *udl_set_display_mode(char *buf, struct drm_display_mode *mode)
149 {
150 	u16 reg01 = mode->crtc_htotal - mode->crtc_hsync_start;
151 	u16 reg03 = reg01 + mode->crtc_hdisplay;
152 	u16 reg05 = mode->crtc_vtotal - mode->crtc_vsync_start;
153 	u16 reg07 = reg05 + mode->crtc_vdisplay;
154 	u16 reg09 = mode->crtc_htotal - 1;
155 	u16 reg0b = 1; /* libdlo hardcodes hsync start to 1 */
156 	u16 reg0d = mode->crtc_hsync_end - mode->crtc_hsync_start + 1;
157 	u16 reg0f = mode->hdisplay;
158 	u16 reg11 = mode->crtc_vtotal;
159 	u16 reg13 = 0; /* libdlo hardcodes vsync start to 0 */
160 	u16 reg15 = mode->crtc_vsync_end - mode->crtc_vsync_start;
161 	u16 reg17 = mode->crtc_vdisplay;
162 	u16 reg1b = mode->clock / 5;
163 
164 	buf = udl_set_register_lfsr16(buf, UDL_REG_XDISPLAYSTART, reg01);
165 	buf = udl_set_register_lfsr16(buf, UDL_REG_XDISPLAYEND, reg03);
166 	buf = udl_set_register_lfsr16(buf, UDL_REG_YDISPLAYSTART, reg05);
167 	buf = udl_set_register_lfsr16(buf, UDL_REG_YDISPLAYEND, reg07);
168 	buf = udl_set_register_lfsr16(buf, UDL_REG_XENDCOUNT, reg09);
169 	buf = udl_set_register_lfsr16(buf, UDL_REG_HSYNCSTART, reg0b);
170 	buf = udl_set_register_lfsr16(buf, UDL_REG_HSYNCEND, reg0d);
171 	buf = udl_set_register_16(buf, UDL_REG_HPIXELS, reg0f);
172 	buf = udl_set_register_lfsr16(buf, UDL_REG_YENDCOUNT, reg11);
173 	buf = udl_set_register_lfsr16(buf, UDL_REG_VSYNCSTART, reg13);
174 	buf = udl_set_register_lfsr16(buf, UDL_REG_VSYNCEND, reg15);
175 	buf = udl_set_register_16(buf, UDL_REG_VPIXELS, reg17);
176 	buf = udl_set_register_16be(buf, UDL_REG_PIXELCLOCK5KHZ, reg1b);
177 
178 	return buf;
179 }
180 
181 static char *udl_dummy_render(char *wrptr)
182 {
183 	*wrptr++ = UDL_MSG_BULK;
184 	*wrptr++ = UDL_CMD_WRITECOPY16;
185 	*wrptr++ = 0x00; /* from addr */
186 	*wrptr++ = 0x00;
187 	*wrptr++ = 0x00;
188 	*wrptr++ = 0x01; /* one pixel */
189 	*wrptr++ = 0x00; /* to address */
190 	*wrptr++ = 0x00;
191 	*wrptr++ = 0x00;
192 	return wrptr;
193 }
194 
195 static long udl_log_cpp(unsigned int cpp)
196 {
197 	if (WARN_ON(!is_power_of_2(cpp)))
198 		return -EINVAL;
199 	return __ffs(cpp);
200 }
201 
202 static int udl_handle_damage(struct drm_framebuffer *fb,
203 			     const struct iosys_map *map,
204 			     const struct drm_rect *clip)
205 {
206 	struct drm_device *dev = fb->dev;
207 	void *vaddr = map->vaddr; /* TODO: Use mapping abstraction properly */
208 	int i, ret;
209 	char *cmd;
210 	struct urb *urb;
211 	int log_bpp;
212 
213 	ret = udl_log_cpp(fb->format->cpp[0]);
214 	if (ret < 0)
215 		return ret;
216 	log_bpp = ret;
217 
218 	urb = udl_get_urb(dev);
219 	if (!urb)
220 		return -ENOMEM;
221 	cmd = urb->transfer_buffer;
222 
223 	for (i = clip->y1; i < clip->y2; i++) {
224 		const int line_offset = fb->pitches[0] * i;
225 		const int byte_offset = line_offset + (clip->x1 << log_bpp);
226 		const int dev_byte_offset = (fb->width * i + clip->x1) << log_bpp;
227 		const int byte_width = drm_rect_width(clip) << log_bpp;
228 		ret = udl_render_hline(dev, log_bpp, &urb, (char *)vaddr,
229 				       &cmd, byte_offset, dev_byte_offset,
230 				       byte_width);
231 		if (ret)
232 			return ret;
233 	}
234 
235 	if (cmd > (char *)urb->transfer_buffer) {
236 		/* Send partial buffer remaining before exiting */
237 		int len;
238 		if (cmd < (char *)urb->transfer_buffer + urb->transfer_buffer_length)
239 			*cmd++ = UDL_MSG_BULK;
240 		len = cmd - (char *)urb->transfer_buffer;
241 		ret = udl_submit_urb(dev, urb, len);
242 	} else {
243 		udl_urb_completion(urb);
244 	}
245 
246 	return 0;
247 }
248 
249 /*
250  * Primary plane
251  */
252 
253 static const uint32_t udl_primary_plane_formats[] = {
254 	DRM_FORMAT_RGB565,
255 	DRM_FORMAT_XRGB8888,
256 };
257 
258 static const uint64_t udl_primary_plane_fmtmods[] = {
259 	DRM_FORMAT_MOD_LINEAR,
260 	DRM_FORMAT_MOD_INVALID
261 };
262 
263 static int udl_primary_plane_helper_atomic_check(struct drm_plane *plane,
264 						 struct drm_atomic_state *state)
265 {
266 	struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state, plane);
267 	struct drm_crtc *new_crtc = new_plane_state->crtc;
268 	struct drm_crtc_state *new_crtc_state = NULL;
269 
270 	if (new_crtc)
271 		new_crtc_state = drm_atomic_get_new_crtc_state(state, new_crtc);
272 
273 	return drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state,
274 						   DRM_PLANE_NO_SCALING,
275 						   DRM_PLANE_NO_SCALING,
276 						   false, false);
277 }
278 
279 static void udl_primary_plane_helper_atomic_update(struct drm_plane *plane,
280 						   struct drm_atomic_state *state)
281 {
282 	struct drm_device *dev = plane->dev;
283 	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
284 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
285 	struct drm_framebuffer *fb = plane_state->fb;
286 	struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane);
287 	struct drm_atomic_helper_damage_iter iter;
288 	struct drm_rect damage;
289 	int ret, idx;
290 
291 	if (!fb)
292 		return; /* no framebuffer; plane is disabled */
293 
294 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
295 	if (ret)
296 		return;
297 
298 	if (!drm_dev_enter(dev, &idx))
299 		goto out_drm_gem_fb_end_cpu_access;
300 
301 	drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state);
302 	drm_atomic_for_each_plane_damage(&iter, &damage) {
303 		udl_handle_damage(fb, &shadow_plane_state->data[0], &damage);
304 	}
305 
306 	drm_dev_exit(idx);
307 
308 out_drm_gem_fb_end_cpu_access:
309 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
310 }
311 
312 static const struct drm_plane_helper_funcs udl_primary_plane_helper_funcs = {
313 	DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
314 	.atomic_check = udl_primary_plane_helper_atomic_check,
315 	.atomic_update = udl_primary_plane_helper_atomic_update,
316 };
317 
318 static const struct drm_plane_funcs udl_primary_plane_funcs = {
319 	.update_plane = drm_atomic_helper_update_plane,
320 	.disable_plane = drm_atomic_helper_disable_plane,
321 	.destroy = drm_plane_cleanup,
322 	DRM_GEM_SHADOW_PLANE_FUNCS,
323 };
324 
325 /*
326  * CRTC
327  */
328 
329 static void udl_crtc_helper_atomic_enable(struct drm_crtc *crtc, struct drm_atomic_state *state)
330 {
331 	struct drm_device *dev = crtc->dev;
332 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
333 	struct drm_display_mode *mode = &crtc_state->mode;
334 	struct urb *urb;
335 	char *buf;
336 	int idx;
337 
338 	if (!drm_dev_enter(dev, &idx))
339 		return;
340 
341 	urb = udl_get_urb(dev);
342 	if (!urb)
343 		goto out;
344 
345 	buf = (char *)urb->transfer_buffer;
346 	buf = udl_vidreg_lock(buf);
347 	buf = udl_set_color_depth(buf, UDL_COLORDEPTH_16BPP);
348 	/* set base for 16bpp segment to 0 */
349 	buf = udl_set_base16bpp(buf, 0);
350 	/* set base for 8bpp segment to end of fb */
351 	buf = udl_set_base8bpp(buf, 2 * mode->vdisplay * mode->hdisplay);
352 	buf = udl_set_display_mode(buf, mode);
353 	buf = udl_set_blank_mode(buf, UDL_BLANKMODE_ON);
354 	buf = udl_vidreg_unlock(buf);
355 	buf = udl_dummy_render(buf);
356 
357 	udl_submit_urb(dev, urb, buf - (char *)urb->transfer_buffer);
358 
359 out:
360 	drm_dev_exit(idx);
361 }
362 
363 static void udl_crtc_helper_atomic_disable(struct drm_crtc *crtc, struct drm_atomic_state *state)
364 {
365 	struct drm_device *dev = crtc->dev;
366 	struct urb *urb;
367 	char *buf;
368 	int idx;
369 
370 	if (!drm_dev_enter(dev, &idx))
371 		return;
372 
373 	urb = udl_get_urb(dev);
374 	if (!urb)
375 		goto out;
376 
377 	buf = (char *)urb->transfer_buffer;
378 	buf = udl_vidreg_lock(buf);
379 	buf = udl_set_blank_mode(buf, UDL_BLANKMODE_POWERDOWN);
380 	buf = udl_vidreg_unlock(buf);
381 	buf = udl_dummy_render(buf);
382 
383 	udl_submit_urb(dev, urb, buf - (char *)urb->transfer_buffer);
384 
385 out:
386 	drm_dev_exit(idx);
387 }
388 
389 static const struct drm_crtc_helper_funcs udl_crtc_helper_funcs = {
390 	.atomic_check = drm_crtc_helper_atomic_check,
391 	.atomic_enable = udl_crtc_helper_atomic_enable,
392 	.atomic_disable = udl_crtc_helper_atomic_disable,
393 };
394 
395 static const struct drm_crtc_funcs udl_crtc_funcs = {
396 	.reset = drm_atomic_helper_crtc_reset,
397 	.destroy = drm_crtc_cleanup,
398 	.set_config = drm_atomic_helper_set_config,
399 	.page_flip = drm_atomic_helper_page_flip,
400 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
401 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
402 };
403 
404 /*
405  * Encoder
406  */
407 
408 static const struct drm_encoder_funcs udl_encoder_funcs = {
409 	.destroy = drm_encoder_cleanup,
410 };
411 
412 /*
413  * Connector
414  */
415 
416 static int udl_connector_helper_get_modes(struct drm_connector *connector)
417 {
418 	struct udl_connector *udl_connector = to_udl_connector(connector);
419 
420 	drm_connector_update_edid_property(connector, udl_connector->edid);
421 	if (udl_connector->edid)
422 		return drm_add_edid_modes(connector, udl_connector->edid);
423 
424 	return 0;
425 }
426 
427 static const struct drm_connector_helper_funcs udl_connector_helper_funcs = {
428 	.get_modes = udl_connector_helper_get_modes,
429 };
430 
431 static int udl_get_edid_block(void *data, u8 *buf, unsigned int block, size_t len)
432 {
433 	struct udl_device *udl = data;
434 	struct drm_device *dev = &udl->drm;
435 	struct usb_device *udev = udl_to_usb_device(udl);
436 	u8 *read_buff;
437 	int ret;
438 	size_t i;
439 
440 	read_buff = kmalloc(2, GFP_KERNEL);
441 	if (!read_buff)
442 		return -ENOMEM;
443 
444 	for (i = 0; i < len; i++) {
445 		int bval = (i + block * EDID_LENGTH) << 8;
446 
447 		ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
448 				      0x02, (0x80 | (0x02 << 5)), bval,
449 				      0xA1, read_buff, 2, USB_CTRL_GET_TIMEOUT);
450 		if (ret < 0) {
451 			drm_err(dev, "Read EDID byte %zu failed err %x\n", i, ret);
452 			goto err_kfree;
453 		} else if (ret < 1) {
454 			ret = -EIO;
455 			drm_err(dev, "Read EDID byte %zu failed\n", i);
456 			goto err_kfree;
457 		}
458 
459 		buf[i] = read_buff[1];
460 	}
461 
462 	kfree(read_buff);
463 
464 	return 0;
465 
466 err_kfree:
467 	kfree(read_buff);
468 	return ret;
469 }
470 
471 static enum drm_connector_status udl_connector_detect(struct drm_connector *connector, bool force)
472 {
473 	struct drm_device *dev = connector->dev;
474 	struct udl_device *udl = to_udl(dev);
475 	struct udl_connector *udl_connector = to_udl_connector(connector);
476 	enum drm_connector_status status = connector_status_disconnected;
477 	int idx;
478 
479 	/* cleanup previous EDID */
480 	kfree(udl_connector->edid);
481 	udl_connector->edid = NULL;
482 
483 	if (!drm_dev_enter(dev, &idx))
484 		return connector_status_disconnected;
485 
486 	udl_connector->edid = drm_do_get_edid(connector, udl_get_edid_block, udl);
487 	if (udl_connector->edid)
488 		status = connector_status_connected;
489 
490 	drm_dev_exit(idx);
491 
492 	return status;
493 }
494 
495 static void udl_connector_destroy(struct drm_connector *connector)
496 {
497 	struct udl_connector *udl_connector = to_udl_connector(connector);
498 
499 	drm_connector_cleanup(connector);
500 	kfree(udl_connector->edid);
501 	kfree(udl_connector);
502 }
503 
504 static const struct drm_connector_funcs udl_connector_funcs = {
505 	.reset = drm_atomic_helper_connector_reset,
506 	.detect = udl_connector_detect,
507 	.fill_modes = drm_helper_probe_single_connector_modes,
508 	.destroy = udl_connector_destroy,
509 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
510 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
511 };
512 
513 struct drm_connector *udl_connector_init(struct drm_device *dev)
514 {
515 	struct udl_connector *udl_connector;
516 	struct drm_connector *connector;
517 	int ret;
518 
519 	udl_connector = kzalloc(sizeof(*udl_connector), GFP_KERNEL);
520 	if (!udl_connector)
521 		return ERR_PTR(-ENOMEM);
522 
523 	connector = &udl_connector->connector;
524 	ret = drm_connector_init(dev, connector, &udl_connector_funcs, DRM_MODE_CONNECTOR_VGA);
525 	if (ret)
526 		goto err_kfree;
527 
528 	drm_connector_helper_add(connector, &udl_connector_helper_funcs);
529 
530 	connector->polled = DRM_CONNECTOR_POLL_HPD |
531 			    DRM_CONNECTOR_POLL_CONNECT |
532 			    DRM_CONNECTOR_POLL_DISCONNECT;
533 
534 	return connector;
535 
536 err_kfree:
537 	kfree(udl_connector);
538 	return ERR_PTR(ret);
539 }
540 
541 /*
542  * Modesetting
543  */
544 
545 static enum drm_mode_status udl_mode_config_mode_valid(struct drm_device *dev,
546 						       const struct drm_display_mode *mode)
547 {
548 	struct udl_device *udl = to_udl(dev);
549 
550 	if (udl->sku_pixel_limit) {
551 		if (mode->vdisplay * mode->hdisplay > udl->sku_pixel_limit)
552 			return MODE_MEM;
553 	}
554 
555 	return MODE_OK;
556 }
557 
558 static const struct drm_mode_config_funcs udl_mode_config_funcs = {
559 	.fb_create = drm_gem_fb_create_with_dirty,
560 	.mode_valid = udl_mode_config_mode_valid,
561 	.atomic_check  = drm_atomic_helper_check,
562 	.atomic_commit = drm_atomic_helper_commit,
563 };
564 
565 int udl_modeset_init(struct drm_device *dev)
566 {
567 	struct udl_device *udl = to_udl(dev);
568 	struct drm_plane *primary_plane;
569 	struct drm_crtc *crtc;
570 	struct drm_encoder *encoder;
571 	struct drm_connector *connector;
572 	int ret;
573 
574 	ret = drmm_mode_config_init(dev);
575 	if (ret)
576 		return ret;
577 
578 	dev->mode_config.min_width = 640;
579 	dev->mode_config.min_height = 480;
580 	dev->mode_config.max_width = 2048;
581 	dev->mode_config.max_height = 2048;
582 	dev->mode_config.preferred_depth = 16;
583 	dev->mode_config.funcs = &udl_mode_config_funcs;
584 
585 	primary_plane = &udl->primary_plane;
586 	ret = drm_universal_plane_init(dev, primary_plane, 0,
587 				       &udl_primary_plane_funcs,
588 				       udl_primary_plane_formats,
589 				       ARRAY_SIZE(udl_primary_plane_formats),
590 				       udl_primary_plane_fmtmods,
591 				       DRM_PLANE_TYPE_PRIMARY, NULL);
592 	if (ret)
593 		return ret;
594 	drm_plane_helper_add(primary_plane, &udl_primary_plane_helper_funcs);
595 	drm_plane_enable_fb_damage_clips(primary_plane);
596 
597 	crtc = &udl->crtc;
598 	ret = drm_crtc_init_with_planes(dev, crtc, primary_plane, NULL,
599 					&udl_crtc_funcs, NULL);
600 	if (ret)
601 		return ret;
602 	drm_crtc_helper_add(crtc, &udl_crtc_helper_funcs);
603 
604 	encoder = &udl->encoder;
605 	ret = drm_encoder_init(dev, encoder, &udl_encoder_funcs, DRM_MODE_ENCODER_DAC, NULL);
606 	if (ret)
607 		return ret;
608 	encoder->possible_crtcs = drm_crtc_mask(crtc);
609 
610 	connector = udl_connector_init(dev);
611 	if (IS_ERR(connector))
612 		return PTR_ERR(connector);
613 	ret = drm_connector_attach_encoder(connector, encoder);
614 	if (ret)
615 		return ret;
616 
617 	drm_mode_config_reset(dev);
618 
619 	return 0;
620 }
621