xref: /openbmc/linux/arch/arm/mach-omap2/display.c (revision a06c488d)
1 /*
2  * OMAP2plus display device setup / initialization.
3  *
4  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
5  *	Senthilvadivu Guruswamy
6  *	Sumit Semwal
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
13  * kind, whether express or implied; without even the implied warranty
14  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 #include <linux/string.h>
19 #include <linux/kernel.h>
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/io.h>
23 #include <linux/clk.h>
24 #include <linux/err.h>
25 #include <linux/delay.h>
26 #include <linux/of.h>
27 #include <linux/of_platform.h>
28 #include <linux/slab.h>
29 #include <linux/mfd/syscon.h>
30 #include <linux/regmap.h>
31 
32 #include <video/omapdss.h>
33 #include "omap_hwmod.h"
34 #include "omap_device.h"
35 #include "omap-pm.h"
36 #include "common.h"
37 
38 #include "soc.h"
39 #include "iomap.h"
40 #include "control.h"
41 #include "display.h"
42 #include "prm.h"
43 
44 #define DISPC_CONTROL		0x0040
45 #define DISPC_CONTROL2		0x0238
46 #define DISPC_CONTROL3		0x0848
47 #define DISPC_IRQSTATUS		0x0018
48 
49 #define DSS_SYSCONFIG		0x10
50 #define DSS_SYSSTATUS		0x14
51 #define DSS_CONTROL		0x40
52 #define DSS_SDI_CONTROL		0x44
53 #define DSS_PLL_CONTROL		0x48
54 
55 #define LCD_EN_MASK		(0x1 << 0)
56 #define DIGIT_EN_MASK		(0x1 << 1)
57 
58 #define FRAMEDONE_IRQ_SHIFT	0
59 #define EVSYNC_EVEN_IRQ_SHIFT	2
60 #define EVSYNC_ODD_IRQ_SHIFT	3
61 #define FRAMEDONE2_IRQ_SHIFT	22
62 #define FRAMEDONE3_IRQ_SHIFT	30
63 #define FRAMEDONETV_IRQ_SHIFT	24
64 
65 /*
66  * FRAMEDONE_IRQ_TIMEOUT: how long (in milliseconds) to wait during DISPC
67  *     reset before deciding that something has gone wrong
68  */
69 #define FRAMEDONE_IRQ_TIMEOUT		100
70 
71 static struct platform_device omap_display_device = {
72 	.name          = "omapdss",
73 	.id            = -1,
74 	.dev            = {
75 		.platform_data = NULL,
76 	},
77 };
78 
79 struct omap_dss_hwmod_data {
80 	const char *oh_name;
81 	const char *dev_name;
82 	const int id;
83 };
84 
85 static const struct omap_dss_hwmod_data omap2_dss_hwmod_data[] __initconst = {
86 	{ "dss_core", "omapdss_dss", -1 },
87 	{ "dss_dispc", "omapdss_dispc", -1 },
88 	{ "dss_rfbi", "omapdss_rfbi", -1 },
89 	{ "dss_venc", "omapdss_venc", -1 },
90 };
91 
92 static const struct omap_dss_hwmod_data omap3_dss_hwmod_data[] __initconst = {
93 	{ "dss_core", "omapdss_dss", -1 },
94 	{ "dss_dispc", "omapdss_dispc", -1 },
95 	{ "dss_rfbi", "omapdss_rfbi", -1 },
96 	{ "dss_venc", "omapdss_venc", -1 },
97 	{ "dss_dsi1", "omapdss_dsi", 0 },
98 };
99 
100 static const struct omap_dss_hwmod_data omap4_dss_hwmod_data[] __initconst = {
101 	{ "dss_core", "omapdss_dss", -1 },
102 	{ "dss_dispc", "omapdss_dispc", -1 },
103 	{ "dss_rfbi", "omapdss_rfbi", -1 },
104 	{ "dss_dsi1", "omapdss_dsi", 0 },
105 	{ "dss_dsi2", "omapdss_dsi", 1 },
106 	{ "dss_hdmi", "omapdss_hdmi", -1 },
107 };
108 
109 #define OMAP4_DSIPHY_SYSCON_OFFSET		0x78
110 
111 static struct regmap *omap4_dsi_mux_syscon;
112 
113 static int omap4_dsi_mux_pads(int dsi_id, unsigned lanes)
114 {
115 	u32 enable_mask, enable_shift;
116 	u32 pipd_mask, pipd_shift;
117 	u32 reg;
118 
119 	if (dsi_id == 0) {
120 		enable_mask = OMAP4_DSI1_LANEENABLE_MASK;
121 		enable_shift = OMAP4_DSI1_LANEENABLE_SHIFT;
122 		pipd_mask = OMAP4_DSI1_PIPD_MASK;
123 		pipd_shift = OMAP4_DSI1_PIPD_SHIFT;
124 	} else if (dsi_id == 1) {
125 		enable_mask = OMAP4_DSI2_LANEENABLE_MASK;
126 		enable_shift = OMAP4_DSI2_LANEENABLE_SHIFT;
127 		pipd_mask = OMAP4_DSI2_PIPD_MASK;
128 		pipd_shift = OMAP4_DSI2_PIPD_SHIFT;
129 	} else {
130 		return -ENODEV;
131 	}
132 
133 	regmap_read(omap4_dsi_mux_syscon, OMAP4_DSIPHY_SYSCON_OFFSET, &reg);
134 
135 	reg &= ~enable_mask;
136 	reg &= ~pipd_mask;
137 
138 	reg |= (lanes << enable_shift) & enable_mask;
139 	reg |= (lanes << pipd_shift) & pipd_mask;
140 
141 	regmap_write(omap4_dsi_mux_syscon, OMAP4_DSIPHY_SYSCON_OFFSET, reg);
142 
143 	return 0;
144 }
145 
146 static int omap_dsi_enable_pads(int dsi_id, unsigned lane_mask)
147 {
148 	if (cpu_is_omap44xx())
149 		return omap4_dsi_mux_pads(dsi_id, lane_mask);
150 
151 	return 0;
152 }
153 
154 static void omap_dsi_disable_pads(int dsi_id, unsigned lane_mask)
155 {
156 	if (cpu_is_omap44xx())
157 		omap4_dsi_mux_pads(dsi_id, 0);
158 }
159 
160 static int omap_dss_set_min_bus_tput(struct device *dev, unsigned long tput)
161 {
162 	return omap_pm_set_min_bus_tput(dev, OCP_INITIATOR_AGENT, tput);
163 }
164 
165 static struct platform_device *create_dss_pdev(const char *pdev_name,
166 		int pdev_id, const char *oh_name, void *pdata, int pdata_len,
167 		struct platform_device *parent)
168 {
169 	struct platform_device *pdev;
170 	struct omap_device *od;
171 	struct omap_hwmod *ohs[1];
172 	struct omap_hwmod *oh;
173 	int r;
174 
175 	oh = omap_hwmod_lookup(oh_name);
176 	if (!oh) {
177 		pr_err("Could not look up %s\n", oh_name);
178 		r = -ENODEV;
179 		goto err;
180 	}
181 
182 	pdev = platform_device_alloc(pdev_name, pdev_id);
183 	if (!pdev) {
184 		pr_err("Could not create pdev for %s\n", pdev_name);
185 		r = -ENOMEM;
186 		goto err;
187 	}
188 
189 	if (parent != NULL)
190 		pdev->dev.parent = &parent->dev;
191 
192 	if (pdev->id != -1)
193 		dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
194 	else
195 		dev_set_name(&pdev->dev, "%s", pdev->name);
196 
197 	ohs[0] = oh;
198 	od = omap_device_alloc(pdev, ohs, 1);
199 	if (IS_ERR(od)) {
200 		pr_err("Could not alloc omap_device for %s\n", pdev_name);
201 		r = -ENOMEM;
202 		goto err;
203 	}
204 
205 	r = platform_device_add_data(pdev, pdata, pdata_len);
206 	if (r) {
207 		pr_err("Could not set pdata for %s\n", pdev_name);
208 		goto err;
209 	}
210 
211 	r = omap_device_register(pdev);
212 	if (r) {
213 		pr_err("Could not register omap_device for %s\n", pdev_name);
214 		goto err;
215 	}
216 
217 	return pdev;
218 
219 err:
220 	return ERR_PTR(r);
221 }
222 
223 static struct platform_device *create_simple_dss_pdev(const char *pdev_name,
224 		int pdev_id, void *pdata, int pdata_len,
225 		struct platform_device *parent)
226 {
227 	struct platform_device *pdev;
228 	int r;
229 
230 	pdev = platform_device_alloc(pdev_name, pdev_id);
231 	if (!pdev) {
232 		pr_err("Could not create pdev for %s\n", pdev_name);
233 		r = -ENOMEM;
234 		goto err;
235 	}
236 
237 	if (parent != NULL)
238 		pdev->dev.parent = &parent->dev;
239 
240 	if (pdev->id != -1)
241 		dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
242 	else
243 		dev_set_name(&pdev->dev, "%s", pdev->name);
244 
245 	r = platform_device_add_data(pdev, pdata, pdata_len);
246 	if (r) {
247 		pr_err("Could not set pdata for %s\n", pdev_name);
248 		goto err;
249 	}
250 
251 	r = platform_device_add(pdev);
252 	if (r) {
253 		pr_err("Could not register platform_device for %s\n", pdev_name);
254 		goto err;
255 	}
256 
257 	return pdev;
258 
259 err:
260 	return ERR_PTR(r);
261 }
262 
263 static enum omapdss_version __init omap_display_get_version(void)
264 {
265 	if (cpu_is_omap24xx())
266 		return OMAPDSS_VER_OMAP24xx;
267 	else if (cpu_is_omap3630())
268 		return OMAPDSS_VER_OMAP3630;
269 	else if (cpu_is_omap34xx()) {
270 		if (soc_is_am35xx()) {
271 			return OMAPDSS_VER_AM35xx;
272 		} else {
273 			if (omap_rev() < OMAP3430_REV_ES3_0)
274 				return OMAPDSS_VER_OMAP34xx_ES1;
275 			else
276 				return OMAPDSS_VER_OMAP34xx_ES3;
277 		}
278 	} else if (omap_rev() == OMAP4430_REV_ES1_0)
279 		return OMAPDSS_VER_OMAP4430_ES1;
280 	else if (omap_rev() == OMAP4430_REV_ES2_0 ||
281 			omap_rev() == OMAP4430_REV_ES2_1 ||
282 			omap_rev() == OMAP4430_REV_ES2_2)
283 		return OMAPDSS_VER_OMAP4430_ES2;
284 	else if (cpu_is_omap44xx())
285 		return OMAPDSS_VER_OMAP4;
286 	else if (soc_is_omap54xx())
287 		return OMAPDSS_VER_OMAP5;
288 	else if (soc_is_am43xx())
289 		return OMAPDSS_VER_AM43xx;
290 	else if (soc_is_dra7xx())
291 		return OMAPDSS_VER_DRA7xx;
292 	else
293 		return OMAPDSS_VER_UNKNOWN;
294 }
295 
296 int __init omap_display_init(struct omap_dss_board_info *board_data)
297 {
298 	int r = 0;
299 	struct platform_device *pdev;
300 	int i, oh_count;
301 	const struct omap_dss_hwmod_data *curr_dss_hwmod;
302 	struct platform_device *dss_pdev;
303 	enum omapdss_version ver;
304 
305 	/* create omapdss device */
306 
307 	ver = omap_display_get_version();
308 
309 	if (ver == OMAPDSS_VER_UNKNOWN) {
310 		pr_err("DSS not supported on this SoC\n");
311 		return -ENODEV;
312 	}
313 
314 	board_data->version = ver;
315 	board_data->dsi_enable_pads = omap_dsi_enable_pads;
316 	board_data->dsi_disable_pads = omap_dsi_disable_pads;
317 	board_data->set_min_bus_tput = omap_dss_set_min_bus_tput;
318 
319 	omap_display_device.dev.platform_data = board_data;
320 
321 	r = platform_device_register(&omap_display_device);
322 	if (r < 0) {
323 		pr_err("Unable to register omapdss device\n");
324 		return r;
325 	}
326 
327 	/* create devices for dss hwmods */
328 
329 	if (cpu_is_omap24xx()) {
330 		curr_dss_hwmod = omap2_dss_hwmod_data;
331 		oh_count = ARRAY_SIZE(omap2_dss_hwmod_data);
332 	} else if (cpu_is_omap34xx()) {
333 		curr_dss_hwmod = omap3_dss_hwmod_data;
334 		oh_count = ARRAY_SIZE(omap3_dss_hwmod_data);
335 	} else {
336 		curr_dss_hwmod = omap4_dss_hwmod_data;
337 		oh_count = ARRAY_SIZE(omap4_dss_hwmod_data);
338 	}
339 
340 	/*
341 	 * First create the pdev for dss_core, which is used as a parent device
342 	 * by the other dss pdevs. Note: dss_core has to be the first item in
343 	 * the hwmod list.
344 	 */
345 	dss_pdev = create_dss_pdev(curr_dss_hwmod[0].dev_name,
346 			curr_dss_hwmod[0].id,
347 			curr_dss_hwmod[0].oh_name,
348 			board_data, sizeof(*board_data),
349 			NULL);
350 
351 	if (IS_ERR(dss_pdev)) {
352 		pr_err("Could not build omap_device for %s\n",
353 				curr_dss_hwmod[0].oh_name);
354 
355 		return PTR_ERR(dss_pdev);
356 	}
357 
358 	for (i = 1; i < oh_count; i++) {
359 		pdev = create_dss_pdev(curr_dss_hwmod[i].dev_name,
360 				curr_dss_hwmod[i].id,
361 				curr_dss_hwmod[i].oh_name,
362 				board_data, sizeof(*board_data),
363 				dss_pdev);
364 
365 		if (IS_ERR(pdev)) {
366 			pr_err("Could not build omap_device for %s\n",
367 					curr_dss_hwmod[i].oh_name);
368 
369 			return PTR_ERR(pdev);
370 		}
371 	}
372 
373 	/* Create devices for DPI and SDI */
374 
375 	pdev = create_simple_dss_pdev("omapdss_dpi", 0,
376 			board_data, sizeof(*board_data), dss_pdev);
377 	if (IS_ERR(pdev)) {
378 		pr_err("Could not build platform_device for omapdss_dpi\n");
379 		return PTR_ERR(pdev);
380 	}
381 
382 	if (cpu_is_omap34xx()) {
383 		pdev = create_simple_dss_pdev("omapdss_sdi", 0,
384 				board_data, sizeof(*board_data), dss_pdev);
385 		if (IS_ERR(pdev)) {
386 			pr_err("Could not build platform_device for omapdss_sdi\n");
387 			return PTR_ERR(pdev);
388 		}
389 	}
390 
391 	/* create DRM device */
392 	r = omap_init_drm();
393 	if (r < 0) {
394 		pr_err("Unable to register omapdrm device\n");
395 		return r;
396 	}
397 
398 	/* create vrfb device */
399 	r = omap_init_vrfb();
400 	if (r < 0) {
401 		pr_err("Unable to register omapvrfb device\n");
402 		return r;
403 	}
404 
405 	/* create FB device */
406 	r = omap_init_fb();
407 	if (r < 0) {
408 		pr_err("Unable to register omapfb device\n");
409 		return r;
410 	}
411 
412 	/* create V4L2 display device */
413 	r = omap_init_vout();
414 	if (r < 0) {
415 		pr_err("Unable to register omap_vout device\n");
416 		return r;
417 	}
418 
419 	return 0;
420 }
421 
422 static void dispc_disable_outputs(void)
423 {
424 	u32 v, irq_mask = 0;
425 	bool lcd_en, digit_en, lcd2_en = false, lcd3_en = false;
426 	int i;
427 	struct omap_dss_dispc_dev_attr *da;
428 	struct omap_hwmod *oh;
429 
430 	oh = omap_hwmod_lookup("dss_dispc");
431 	if (!oh) {
432 		WARN(1, "display: could not disable outputs during reset - could not find dss_dispc hwmod\n");
433 		return;
434 	}
435 
436 	if (!oh->dev_attr) {
437 		pr_err("display: could not disable outputs during reset due to missing dev_attr\n");
438 		return;
439 	}
440 
441 	da = (struct omap_dss_dispc_dev_attr *)oh->dev_attr;
442 
443 	/* store value of LCDENABLE and DIGITENABLE bits */
444 	v = omap_hwmod_read(oh, DISPC_CONTROL);
445 	lcd_en = v & LCD_EN_MASK;
446 	digit_en = v & DIGIT_EN_MASK;
447 
448 	/* store value of LCDENABLE for LCD2 */
449 	if (da->manager_count > 2) {
450 		v = omap_hwmod_read(oh, DISPC_CONTROL2);
451 		lcd2_en = v & LCD_EN_MASK;
452 	}
453 
454 	/* store value of LCDENABLE for LCD3 */
455 	if (da->manager_count > 3) {
456 		v = omap_hwmod_read(oh, DISPC_CONTROL3);
457 		lcd3_en = v & LCD_EN_MASK;
458 	}
459 
460 	if (!(lcd_en | digit_en | lcd2_en | lcd3_en))
461 		return; /* no managers currently enabled */
462 
463 	/*
464 	 * If any manager was enabled, we need to disable it before
465 	 * DSS clocks are disabled or DISPC module is reset
466 	 */
467 	if (lcd_en)
468 		irq_mask |= 1 << FRAMEDONE_IRQ_SHIFT;
469 
470 	if (digit_en) {
471 		if (da->has_framedonetv_irq) {
472 			irq_mask |= 1 << FRAMEDONETV_IRQ_SHIFT;
473 		} else {
474 			irq_mask |= 1 << EVSYNC_EVEN_IRQ_SHIFT |
475 				1 << EVSYNC_ODD_IRQ_SHIFT;
476 		}
477 	}
478 
479 	if (lcd2_en)
480 		irq_mask |= 1 << FRAMEDONE2_IRQ_SHIFT;
481 	if (lcd3_en)
482 		irq_mask |= 1 << FRAMEDONE3_IRQ_SHIFT;
483 
484 	/*
485 	 * clear any previous FRAMEDONE, FRAMEDONETV,
486 	 * EVSYNC_EVEN/ODD, FRAMEDONE2 or FRAMEDONE3 interrupts
487 	 */
488 	omap_hwmod_write(irq_mask, oh, DISPC_IRQSTATUS);
489 
490 	/* disable LCD and TV managers */
491 	v = omap_hwmod_read(oh, DISPC_CONTROL);
492 	v &= ~(LCD_EN_MASK | DIGIT_EN_MASK);
493 	omap_hwmod_write(v, oh, DISPC_CONTROL);
494 
495 	/* disable LCD2 manager */
496 	if (da->manager_count > 2) {
497 		v = omap_hwmod_read(oh, DISPC_CONTROL2);
498 		v &= ~LCD_EN_MASK;
499 		omap_hwmod_write(v, oh, DISPC_CONTROL2);
500 	}
501 
502 	/* disable LCD3 manager */
503 	if (da->manager_count > 3) {
504 		v = omap_hwmod_read(oh, DISPC_CONTROL3);
505 		v &= ~LCD_EN_MASK;
506 		omap_hwmod_write(v, oh, DISPC_CONTROL3);
507 	}
508 
509 	i = 0;
510 	while ((omap_hwmod_read(oh, DISPC_IRQSTATUS) & irq_mask) !=
511 	       irq_mask) {
512 		i++;
513 		if (i > FRAMEDONE_IRQ_TIMEOUT) {
514 			pr_err("didn't get FRAMEDONE1/2/3 or TV interrupt\n");
515 			break;
516 		}
517 		mdelay(1);
518 	}
519 }
520 
521 int omap_dss_reset(struct omap_hwmod *oh)
522 {
523 	struct omap_hwmod_opt_clk *oc;
524 	int c = 0;
525 	int i, r;
526 
527 	if (!(oh->class->sysc->sysc_flags & SYSS_HAS_RESET_STATUS)) {
528 		pr_err("dss_core: hwmod data doesn't contain reset data\n");
529 		return -EINVAL;
530 	}
531 
532 	for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++)
533 		if (oc->_clk)
534 			clk_prepare_enable(oc->_clk);
535 
536 	dispc_disable_outputs();
537 
538 	/* clear SDI registers */
539 	if (cpu_is_omap3430()) {
540 		omap_hwmod_write(0x0, oh, DSS_SDI_CONTROL);
541 		omap_hwmod_write(0x0, oh, DSS_PLL_CONTROL);
542 	}
543 
544 	/*
545 	 * clear DSS_CONTROL register to switch DSS clock sources to
546 	 * PRCM clock, if any
547 	 */
548 	omap_hwmod_write(0x0, oh, DSS_CONTROL);
549 
550 	omap_test_timeout((omap_hwmod_read(oh, oh->class->sysc->syss_offs)
551 				& SYSS_RESETDONE_MASK),
552 			MAX_MODULE_SOFTRESET_WAIT, c);
553 
554 	if (c == MAX_MODULE_SOFTRESET_WAIT)
555 		pr_warn("dss_core: waiting for reset to finish failed\n");
556 	else
557 		pr_debug("dss_core: softreset done\n");
558 
559 	for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++)
560 		if (oc->_clk)
561 			clk_disable_unprepare(oc->_clk);
562 
563 	r = (c == MAX_MODULE_SOFTRESET_WAIT) ? -ETIMEDOUT : 0;
564 
565 	return r;
566 }
567 
568 void __init omapdss_early_init_of(void)
569 {
570 
571 }
572 
573 static const char * const omapdss_compat_names[] __initconst = {
574 	"ti,omap2-dss",
575 	"ti,omap3-dss",
576 	"ti,omap4-dss",
577 	"ti,omap5-dss",
578 	"ti,dra7-dss",
579 };
580 
581 struct device_node * __init omapdss_find_dss_of_node(void)
582 {
583 	struct device_node *node;
584 	int i;
585 
586 	for (i = 0; i < ARRAY_SIZE(omapdss_compat_names); ++i) {
587 		node = of_find_compatible_node(NULL, NULL,
588 			omapdss_compat_names[i]);
589 		if (node)
590 			return node;
591 	}
592 
593 	return NULL;
594 }
595 
596 int __init omapdss_init_of(void)
597 {
598 	int r;
599 	enum omapdss_version ver;
600 	struct device_node *node;
601 	struct platform_device *pdev;
602 
603 	static struct omap_dss_board_info board_data = {
604 		.dsi_enable_pads = omap_dsi_enable_pads,
605 		.dsi_disable_pads = omap_dsi_disable_pads,
606 		.set_min_bus_tput = omap_dss_set_min_bus_tput,
607 	};
608 
609 	/* only create dss helper devices if dss is enabled in the .dts */
610 
611 	node = omapdss_find_dss_of_node();
612 	if (!node)
613 		return 0;
614 
615 	if (!of_device_is_available(node))
616 		return 0;
617 
618 	ver = omap_display_get_version();
619 
620 	if (ver == OMAPDSS_VER_UNKNOWN) {
621 		pr_err("DSS not supported on this SoC\n");
622 		return -ENODEV;
623 	}
624 
625 	pdev = of_find_device_by_node(node);
626 
627 	if (!pdev) {
628 		pr_err("Unable to find DSS platform device\n");
629 		return -ENODEV;
630 	}
631 
632 	r = of_platform_populate(node, NULL, NULL, &pdev->dev);
633 	if (r) {
634 		pr_err("Unable to populate DSS submodule devices\n");
635 		return r;
636 	}
637 
638 	board_data.version = ver;
639 
640 	omap_display_device.dev.platform_data = &board_data;
641 
642 	r = platform_device_register(&omap_display_device);
643 	if (r < 0) {
644 		pr_err("Unable to register omapdss device\n");
645 		return r;
646 	}
647 
648 	/* create DRM device */
649 	r = omap_init_drm();
650 	if (r < 0) {
651 		pr_err("Unable to register omapdrm device\n");
652 		return r;
653 	}
654 
655 	/* create vrfb device */
656 	r = omap_init_vrfb();
657 	if (r < 0) {
658 		pr_err("Unable to register omapvrfb device\n");
659 		return r;
660 	}
661 
662 	/* create FB device */
663 	r = omap_init_fb();
664 	if (r < 0) {
665 		pr_err("Unable to register omapfb device\n");
666 		return r;
667 	}
668 
669 	/* create V4L2 display device */
670 	r = omap_init_vout();
671 	if (r < 0) {
672 		pr_err("Unable to register omap_vout device\n");
673 		return r;
674 	}
675 
676 	/* add DSI info for omap4 */
677 	node = of_find_node_by_name(NULL, "omap4_padconf_global");
678 	if (node)
679 		omap4_dsi_mux_syscon = syscon_node_to_regmap(node);
680 
681 	return 0;
682 }
683