xref: /openbmc/linux/arch/arm/mach-omap2/display.c (revision d0b5e15f)
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 
30 #include <video/omapdss.h>
31 #include "omap_hwmod.h"
32 #include "omap_device.h"
33 #include "omap-pm.h"
34 #include "common.h"
35 
36 #include "soc.h"
37 #include "iomap.h"
38 #include "control.h"
39 #include "display.h"
40 #include "prm.h"
41 
42 #define DISPC_CONTROL		0x0040
43 #define DISPC_CONTROL2		0x0238
44 #define DISPC_CONTROL3		0x0848
45 #define DISPC_IRQSTATUS		0x0018
46 
47 #define DSS_SYSCONFIG		0x10
48 #define DSS_SYSSTATUS		0x14
49 #define DSS_CONTROL		0x40
50 #define DSS_SDI_CONTROL		0x44
51 #define DSS_PLL_CONTROL		0x48
52 
53 #define LCD_EN_MASK		(0x1 << 0)
54 #define DIGIT_EN_MASK		(0x1 << 1)
55 
56 #define FRAMEDONE_IRQ_SHIFT	0
57 #define EVSYNC_EVEN_IRQ_SHIFT	2
58 #define EVSYNC_ODD_IRQ_SHIFT	3
59 #define FRAMEDONE2_IRQ_SHIFT	22
60 #define FRAMEDONE3_IRQ_SHIFT	30
61 #define FRAMEDONETV_IRQ_SHIFT	24
62 
63 /*
64  * FRAMEDONE_IRQ_TIMEOUT: how long (in milliseconds) to wait during DISPC
65  *     reset before deciding that something has gone wrong
66  */
67 #define FRAMEDONE_IRQ_TIMEOUT		100
68 
69 static struct platform_device omap_display_device = {
70 	.name          = "omapdss",
71 	.id            = -1,
72 	.dev            = {
73 		.platform_data = NULL,
74 	},
75 };
76 
77 struct omap_dss_hwmod_data {
78 	const char *oh_name;
79 	const char *dev_name;
80 	const int id;
81 };
82 
83 static const struct omap_dss_hwmod_data omap2_dss_hwmod_data[] __initconst = {
84 	{ "dss_core", "omapdss_dss", -1 },
85 	{ "dss_dispc", "omapdss_dispc", -1 },
86 	{ "dss_rfbi", "omapdss_rfbi", -1 },
87 	{ "dss_venc", "omapdss_venc", -1 },
88 };
89 
90 static const struct omap_dss_hwmod_data omap3_dss_hwmod_data[] __initconst = {
91 	{ "dss_core", "omapdss_dss", -1 },
92 	{ "dss_dispc", "omapdss_dispc", -1 },
93 	{ "dss_rfbi", "omapdss_rfbi", -1 },
94 	{ "dss_venc", "omapdss_venc", -1 },
95 	{ "dss_dsi1", "omapdss_dsi", 0 },
96 };
97 
98 static const struct omap_dss_hwmod_data omap4_dss_hwmod_data[] __initconst = {
99 	{ "dss_core", "omapdss_dss", -1 },
100 	{ "dss_dispc", "omapdss_dispc", -1 },
101 	{ "dss_rfbi", "omapdss_rfbi", -1 },
102 	{ "dss_dsi1", "omapdss_dsi", 0 },
103 	{ "dss_dsi2", "omapdss_dsi", 1 },
104 	{ "dss_hdmi", "omapdss_hdmi", -1 },
105 };
106 
107 static int omap4_dsi_mux_pads(int dsi_id, unsigned lanes)
108 {
109 	u32 enable_mask, enable_shift;
110 	u32 pipd_mask, pipd_shift;
111 	u32 reg;
112 
113 	if (dsi_id == 0) {
114 		enable_mask = OMAP4_DSI1_LANEENABLE_MASK;
115 		enable_shift = OMAP4_DSI1_LANEENABLE_SHIFT;
116 		pipd_mask = OMAP4_DSI1_PIPD_MASK;
117 		pipd_shift = OMAP4_DSI1_PIPD_SHIFT;
118 	} else if (dsi_id == 1) {
119 		enable_mask = OMAP4_DSI2_LANEENABLE_MASK;
120 		enable_shift = OMAP4_DSI2_LANEENABLE_SHIFT;
121 		pipd_mask = OMAP4_DSI2_PIPD_MASK;
122 		pipd_shift = OMAP4_DSI2_PIPD_SHIFT;
123 	} else {
124 		return -ENODEV;
125 	}
126 
127 	reg = omap4_ctrl_pad_readl(OMAP4_CTRL_MODULE_PAD_CORE_CONTROL_DSIPHY);
128 
129 	reg &= ~enable_mask;
130 	reg &= ~pipd_mask;
131 
132 	reg |= (lanes << enable_shift) & enable_mask;
133 	reg |= (lanes << pipd_shift) & pipd_mask;
134 
135 	omap4_ctrl_pad_writel(reg, OMAP4_CTRL_MODULE_PAD_CORE_CONTROL_DSIPHY);
136 
137 	return 0;
138 }
139 
140 static int omap_dsi_enable_pads(int dsi_id, unsigned lane_mask)
141 {
142 	if (cpu_is_omap44xx())
143 		return omap4_dsi_mux_pads(dsi_id, lane_mask);
144 
145 	return 0;
146 }
147 
148 static void omap_dsi_disable_pads(int dsi_id, unsigned lane_mask)
149 {
150 	if (cpu_is_omap44xx())
151 		omap4_dsi_mux_pads(dsi_id, 0);
152 }
153 
154 static int omap_dss_set_min_bus_tput(struct device *dev, unsigned long tput)
155 {
156 	return omap_pm_set_min_bus_tput(dev, OCP_INITIATOR_AGENT, tput);
157 }
158 
159 static struct platform_device *create_dss_pdev(const char *pdev_name,
160 		int pdev_id, const char *oh_name, void *pdata, int pdata_len,
161 		struct platform_device *parent)
162 {
163 	struct platform_device *pdev;
164 	struct omap_device *od;
165 	struct omap_hwmod *ohs[1];
166 	struct omap_hwmod *oh;
167 	int r;
168 
169 	oh = omap_hwmod_lookup(oh_name);
170 	if (!oh) {
171 		pr_err("Could not look up %s\n", oh_name);
172 		r = -ENODEV;
173 		goto err;
174 	}
175 
176 	pdev = platform_device_alloc(pdev_name, pdev_id);
177 	if (!pdev) {
178 		pr_err("Could not create pdev for %s\n", pdev_name);
179 		r = -ENOMEM;
180 		goto err;
181 	}
182 
183 	if (parent != NULL)
184 		pdev->dev.parent = &parent->dev;
185 
186 	if (pdev->id != -1)
187 		dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
188 	else
189 		dev_set_name(&pdev->dev, "%s", pdev->name);
190 
191 	ohs[0] = oh;
192 	od = omap_device_alloc(pdev, ohs, 1);
193 	if (IS_ERR(od)) {
194 		pr_err("Could not alloc omap_device for %s\n", pdev_name);
195 		r = -ENOMEM;
196 		goto err;
197 	}
198 
199 	r = platform_device_add_data(pdev, pdata, pdata_len);
200 	if (r) {
201 		pr_err("Could not set pdata for %s\n", pdev_name);
202 		goto err;
203 	}
204 
205 	r = omap_device_register(pdev);
206 	if (r) {
207 		pr_err("Could not register omap_device for %s\n", pdev_name);
208 		goto err;
209 	}
210 
211 	return pdev;
212 
213 err:
214 	return ERR_PTR(r);
215 }
216 
217 static struct platform_device *create_simple_dss_pdev(const char *pdev_name,
218 		int pdev_id, void *pdata, int pdata_len,
219 		struct platform_device *parent)
220 {
221 	struct platform_device *pdev;
222 	int r;
223 
224 	pdev = platform_device_alloc(pdev_name, pdev_id);
225 	if (!pdev) {
226 		pr_err("Could not create pdev for %s\n", pdev_name);
227 		r = -ENOMEM;
228 		goto err;
229 	}
230 
231 	if (parent != NULL)
232 		pdev->dev.parent = &parent->dev;
233 
234 	if (pdev->id != -1)
235 		dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id);
236 	else
237 		dev_set_name(&pdev->dev, "%s", pdev->name);
238 
239 	r = platform_device_add_data(pdev, pdata, pdata_len);
240 	if (r) {
241 		pr_err("Could not set pdata for %s\n", pdev_name);
242 		goto err;
243 	}
244 
245 	r = platform_device_add(pdev);
246 	if (r) {
247 		pr_err("Could not register platform_device for %s\n", pdev_name);
248 		goto err;
249 	}
250 
251 	return pdev;
252 
253 err:
254 	return ERR_PTR(r);
255 }
256 
257 static enum omapdss_version __init omap_display_get_version(void)
258 {
259 	if (cpu_is_omap24xx())
260 		return OMAPDSS_VER_OMAP24xx;
261 	else if (cpu_is_omap3630())
262 		return OMAPDSS_VER_OMAP3630;
263 	else if (cpu_is_omap34xx()) {
264 		if (soc_is_am35xx()) {
265 			return OMAPDSS_VER_AM35xx;
266 		} else {
267 			if (omap_rev() < OMAP3430_REV_ES3_0)
268 				return OMAPDSS_VER_OMAP34xx_ES1;
269 			else
270 				return OMAPDSS_VER_OMAP34xx_ES3;
271 		}
272 	} else if (omap_rev() == OMAP4430_REV_ES1_0)
273 		return OMAPDSS_VER_OMAP4430_ES1;
274 	else if (omap_rev() == OMAP4430_REV_ES2_0 ||
275 			omap_rev() == OMAP4430_REV_ES2_1 ||
276 			omap_rev() == OMAP4430_REV_ES2_2)
277 		return OMAPDSS_VER_OMAP4430_ES2;
278 	else if (cpu_is_omap44xx())
279 		return OMAPDSS_VER_OMAP4;
280 	else if (soc_is_omap54xx())
281 		return OMAPDSS_VER_OMAP5;
282 	else if (soc_is_am43xx())
283 		return OMAPDSS_VER_AM43xx;
284 	else
285 		return OMAPDSS_VER_UNKNOWN;
286 }
287 
288 int __init omap_display_init(struct omap_dss_board_info *board_data)
289 {
290 	int r = 0;
291 	struct platform_device *pdev;
292 	int i, oh_count;
293 	const struct omap_dss_hwmod_data *curr_dss_hwmod;
294 	struct platform_device *dss_pdev;
295 	enum omapdss_version ver;
296 
297 	/* create omapdss device */
298 
299 	ver = omap_display_get_version();
300 
301 	if (ver == OMAPDSS_VER_UNKNOWN) {
302 		pr_err("DSS not supported on this SoC\n");
303 		return -ENODEV;
304 	}
305 
306 	board_data->version = ver;
307 	board_data->dsi_enable_pads = omap_dsi_enable_pads;
308 	board_data->dsi_disable_pads = omap_dsi_disable_pads;
309 	board_data->set_min_bus_tput = omap_dss_set_min_bus_tput;
310 
311 	omap_display_device.dev.platform_data = board_data;
312 
313 	r = platform_device_register(&omap_display_device);
314 	if (r < 0) {
315 		pr_err("Unable to register omapdss device\n");
316 		return r;
317 	}
318 
319 	/* create devices for dss hwmods */
320 
321 	if (cpu_is_omap24xx()) {
322 		curr_dss_hwmod = omap2_dss_hwmod_data;
323 		oh_count = ARRAY_SIZE(omap2_dss_hwmod_data);
324 	} else if (cpu_is_omap34xx()) {
325 		curr_dss_hwmod = omap3_dss_hwmod_data;
326 		oh_count = ARRAY_SIZE(omap3_dss_hwmod_data);
327 	} else {
328 		curr_dss_hwmod = omap4_dss_hwmod_data;
329 		oh_count = ARRAY_SIZE(omap4_dss_hwmod_data);
330 	}
331 
332 	/*
333 	 * First create the pdev for dss_core, which is used as a parent device
334 	 * by the other dss pdevs. Note: dss_core has to be the first item in
335 	 * the hwmod list.
336 	 */
337 	dss_pdev = create_dss_pdev(curr_dss_hwmod[0].dev_name,
338 			curr_dss_hwmod[0].id,
339 			curr_dss_hwmod[0].oh_name,
340 			board_data, sizeof(*board_data),
341 			NULL);
342 
343 	if (IS_ERR(dss_pdev)) {
344 		pr_err("Could not build omap_device for %s\n",
345 				curr_dss_hwmod[0].oh_name);
346 
347 		return PTR_ERR(dss_pdev);
348 	}
349 
350 	for (i = 1; i < oh_count; i++) {
351 		pdev = create_dss_pdev(curr_dss_hwmod[i].dev_name,
352 				curr_dss_hwmod[i].id,
353 				curr_dss_hwmod[i].oh_name,
354 				board_data, sizeof(*board_data),
355 				dss_pdev);
356 
357 		if (IS_ERR(pdev)) {
358 			pr_err("Could not build omap_device for %s\n",
359 					curr_dss_hwmod[i].oh_name);
360 
361 			return PTR_ERR(pdev);
362 		}
363 	}
364 
365 	/* Create devices for DPI and SDI */
366 
367 	pdev = create_simple_dss_pdev("omapdss_dpi", 0,
368 			board_data, sizeof(*board_data), dss_pdev);
369 	if (IS_ERR(pdev)) {
370 		pr_err("Could not build platform_device for omapdss_dpi\n");
371 		return PTR_ERR(pdev);
372 	}
373 
374 	if (cpu_is_omap34xx()) {
375 		pdev = create_simple_dss_pdev("omapdss_sdi", 0,
376 				board_data, sizeof(*board_data), dss_pdev);
377 		if (IS_ERR(pdev)) {
378 			pr_err("Could not build platform_device for omapdss_sdi\n");
379 			return PTR_ERR(pdev);
380 		}
381 	}
382 
383 	/* create DRM device */
384 	r = omap_init_drm();
385 	if (r < 0) {
386 		pr_err("Unable to register omapdrm device\n");
387 		return r;
388 	}
389 
390 	/* create vrfb device */
391 	r = omap_init_vrfb();
392 	if (r < 0) {
393 		pr_err("Unable to register omapvrfb device\n");
394 		return r;
395 	}
396 
397 	/* create FB device */
398 	r = omap_init_fb();
399 	if (r < 0) {
400 		pr_err("Unable to register omapfb device\n");
401 		return r;
402 	}
403 
404 	/* create V4L2 display device */
405 	r = omap_init_vout();
406 	if (r < 0) {
407 		pr_err("Unable to register omap_vout device\n");
408 		return r;
409 	}
410 
411 	return 0;
412 }
413 
414 static void dispc_disable_outputs(void)
415 {
416 	u32 v, irq_mask = 0;
417 	bool lcd_en, digit_en, lcd2_en = false, lcd3_en = false;
418 	int i;
419 	struct omap_dss_dispc_dev_attr *da;
420 	struct omap_hwmod *oh;
421 
422 	oh = omap_hwmod_lookup("dss_dispc");
423 	if (!oh) {
424 		WARN(1, "display: could not disable outputs during reset - could not find dss_dispc hwmod\n");
425 		return;
426 	}
427 
428 	if (!oh->dev_attr) {
429 		pr_err("display: could not disable outputs during reset due to missing dev_attr\n");
430 		return;
431 	}
432 
433 	da = (struct omap_dss_dispc_dev_attr *)oh->dev_attr;
434 
435 	/* store value of LCDENABLE and DIGITENABLE bits */
436 	v = omap_hwmod_read(oh, DISPC_CONTROL);
437 	lcd_en = v & LCD_EN_MASK;
438 	digit_en = v & DIGIT_EN_MASK;
439 
440 	/* store value of LCDENABLE for LCD2 */
441 	if (da->manager_count > 2) {
442 		v = omap_hwmod_read(oh, DISPC_CONTROL2);
443 		lcd2_en = v & LCD_EN_MASK;
444 	}
445 
446 	/* store value of LCDENABLE for LCD3 */
447 	if (da->manager_count > 3) {
448 		v = omap_hwmod_read(oh, DISPC_CONTROL3);
449 		lcd3_en = v & LCD_EN_MASK;
450 	}
451 
452 	if (!(lcd_en | digit_en | lcd2_en | lcd3_en))
453 		return; /* no managers currently enabled */
454 
455 	/*
456 	 * If any manager was enabled, we need to disable it before
457 	 * DSS clocks are disabled or DISPC module is reset
458 	 */
459 	if (lcd_en)
460 		irq_mask |= 1 << FRAMEDONE_IRQ_SHIFT;
461 
462 	if (digit_en) {
463 		if (da->has_framedonetv_irq) {
464 			irq_mask |= 1 << FRAMEDONETV_IRQ_SHIFT;
465 		} else {
466 			irq_mask |= 1 << EVSYNC_EVEN_IRQ_SHIFT |
467 				1 << EVSYNC_ODD_IRQ_SHIFT;
468 		}
469 	}
470 
471 	if (lcd2_en)
472 		irq_mask |= 1 << FRAMEDONE2_IRQ_SHIFT;
473 	if (lcd3_en)
474 		irq_mask |= 1 << FRAMEDONE3_IRQ_SHIFT;
475 
476 	/*
477 	 * clear any previous FRAMEDONE, FRAMEDONETV,
478 	 * EVSYNC_EVEN/ODD, FRAMEDONE2 or FRAMEDONE3 interrupts
479 	 */
480 	omap_hwmod_write(irq_mask, oh, DISPC_IRQSTATUS);
481 
482 	/* disable LCD and TV managers */
483 	v = omap_hwmod_read(oh, DISPC_CONTROL);
484 	v &= ~(LCD_EN_MASK | DIGIT_EN_MASK);
485 	omap_hwmod_write(v, oh, DISPC_CONTROL);
486 
487 	/* disable LCD2 manager */
488 	if (da->manager_count > 2) {
489 		v = omap_hwmod_read(oh, DISPC_CONTROL2);
490 		v &= ~LCD_EN_MASK;
491 		omap_hwmod_write(v, oh, DISPC_CONTROL2);
492 	}
493 
494 	/* disable LCD3 manager */
495 	if (da->manager_count > 3) {
496 		v = omap_hwmod_read(oh, DISPC_CONTROL3);
497 		v &= ~LCD_EN_MASK;
498 		omap_hwmod_write(v, oh, DISPC_CONTROL3);
499 	}
500 
501 	i = 0;
502 	while ((omap_hwmod_read(oh, DISPC_IRQSTATUS) & irq_mask) !=
503 	       irq_mask) {
504 		i++;
505 		if (i > FRAMEDONE_IRQ_TIMEOUT) {
506 			pr_err("didn't get FRAMEDONE1/2/3 or TV interrupt\n");
507 			break;
508 		}
509 		mdelay(1);
510 	}
511 }
512 
513 int omap_dss_reset(struct omap_hwmod *oh)
514 {
515 	struct omap_hwmod_opt_clk *oc;
516 	int c = 0;
517 	int i, r;
518 
519 	if (!(oh->class->sysc->sysc_flags & SYSS_HAS_RESET_STATUS)) {
520 		pr_err("dss_core: hwmod data doesn't contain reset data\n");
521 		return -EINVAL;
522 	}
523 
524 	for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++)
525 		if (oc->_clk)
526 			clk_prepare_enable(oc->_clk);
527 
528 	dispc_disable_outputs();
529 
530 	/* clear SDI registers */
531 	if (cpu_is_omap3430()) {
532 		omap_hwmod_write(0x0, oh, DSS_SDI_CONTROL);
533 		omap_hwmod_write(0x0, oh, DSS_PLL_CONTROL);
534 	}
535 
536 	/*
537 	 * clear DSS_CONTROL register to switch DSS clock sources to
538 	 * PRCM clock, if any
539 	 */
540 	omap_hwmod_write(0x0, oh, DSS_CONTROL);
541 
542 	omap_test_timeout((omap_hwmod_read(oh, oh->class->sysc->syss_offs)
543 				& SYSS_RESETDONE_MASK),
544 			MAX_MODULE_SOFTRESET_WAIT, c);
545 
546 	if (c == MAX_MODULE_SOFTRESET_WAIT)
547 		pr_warn("dss_core: waiting for reset to finish failed\n");
548 	else
549 		pr_debug("dss_core: softreset done\n");
550 
551 	for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++)
552 		if (oc->_clk)
553 			clk_disable_unprepare(oc->_clk);
554 
555 	r = (c == MAX_MODULE_SOFTRESET_WAIT) ? -ETIMEDOUT : 0;
556 
557 	return r;
558 }
559 
560 void __init omapdss_early_init_of(void)
561 {
562 
563 }
564 
565 struct device_node * __init omapdss_find_dss_of_node(void)
566 {
567 	struct device_node *node;
568 
569 	node = of_find_compatible_node(NULL, NULL, "ti,omap2-dss");
570 	if (node)
571 		return node;
572 
573 	node = of_find_compatible_node(NULL, NULL, "ti,omap3-dss");
574 	if (node)
575 		return node;
576 
577 	node = of_find_compatible_node(NULL, NULL, "ti,omap4-dss");
578 	if (node)
579 		return node;
580 
581 	node = of_find_compatible_node(NULL, NULL, "ti,omap5-dss");
582 	if (node)
583 		return node;
584 
585 	return NULL;
586 }
587 
588 int __init omapdss_init_of(void)
589 {
590 	int r;
591 	enum omapdss_version ver;
592 	struct device_node *node;
593 	struct platform_device *pdev;
594 
595 	static struct omap_dss_board_info board_data = {
596 		.dsi_enable_pads = omap_dsi_enable_pads,
597 		.dsi_disable_pads = omap_dsi_disable_pads,
598 		.set_min_bus_tput = omap_dss_set_min_bus_tput,
599 	};
600 
601 	/* only create dss helper devices if dss is enabled in the .dts */
602 
603 	node = omapdss_find_dss_of_node();
604 	if (!node)
605 		return 0;
606 
607 	if (!of_device_is_available(node))
608 		return 0;
609 
610 	ver = omap_display_get_version();
611 
612 	if (ver == OMAPDSS_VER_UNKNOWN) {
613 		pr_err("DSS not supported on this SoC\n");
614 		return -ENODEV;
615 	}
616 
617 	pdev = of_find_device_by_node(node);
618 
619 	if (!pdev) {
620 		pr_err("Unable to find DSS platform device\n");
621 		return -ENODEV;
622 	}
623 
624 	r = of_platform_populate(node, NULL, NULL, &pdev->dev);
625 	if (r) {
626 		pr_err("Unable to populate DSS submodule devices\n");
627 		return r;
628 	}
629 
630 	board_data.version = ver;
631 
632 	omap_display_device.dev.platform_data = &board_data;
633 
634 	r = platform_device_register(&omap_display_device);
635 	if (r < 0) {
636 		pr_err("Unable to register omapdss device\n");
637 		return r;
638 	}
639 
640 	/* create DRM device */
641 	r = omap_init_drm();
642 	if (r < 0) {
643 		pr_err("Unable to register omapdrm device\n");
644 		return r;
645 	}
646 
647 	/* create vrfb device */
648 	r = omap_init_vrfb();
649 	if (r < 0) {
650 		pr_err("Unable to register omapvrfb device\n");
651 		return r;
652 	}
653 
654 	/* create FB device */
655 	r = omap_init_fb();
656 	if (r < 0) {
657 		pr_err("Unable to register omapfb device\n");
658 		return r;
659 	}
660 
661 	/* create V4L2 display device */
662 	r = omap_init_vout();
663 	if (r < 0) {
664 		pr_err("Unable to register omap_vout device\n");
665 		return r;
666 	}
667 
668 	return 0;
669 }
670