xref: /openbmc/linux/drivers/gpu/drm/omapdrm/dss/dpi.c (revision f220d3eb)
1 /*
2  * Copyright (C) 2009 Nokia Corporation
3  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
4  *
5  * Some code and ideas taken from drivers/video/omap/ driver
6  * by Imre Deak.
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License version 2 as published by
10  * the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15  * more details.
16  *
17  * You should have received a copy of the GNU General Public License along with
18  * this program.  If not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #define DSS_SUBSYS_NAME "DPI"
22 
23 #include <linux/kernel.h>
24 #include <linux/delay.h>
25 #include <linux/export.h>
26 #include <linux/err.h>
27 #include <linux/errno.h>
28 #include <linux/platform_device.h>
29 #include <linux/regulator/consumer.h>
30 #include <linux/string.h>
31 #include <linux/of.h>
32 #include <linux/clk.h>
33 #include <linux/sys_soc.h>
34 
35 #include "omapdss.h"
36 #include "dss.h"
37 
38 struct dpi_data {
39 	struct platform_device *pdev;
40 	enum dss_model dss_model;
41 	struct dss_device *dss;
42 
43 	struct regulator *vdds_dsi_reg;
44 	enum dss_clk_source clk_src;
45 	struct dss_pll *pll;
46 
47 	struct mutex lock;
48 
49 	struct videomode vm;
50 	struct dss_lcd_mgr_config mgr_config;
51 	int data_lines;
52 
53 	struct omap_dss_device output;
54 };
55 
56 static struct dpi_data *dpi_get_data_from_dssdev(struct omap_dss_device *dssdev)
57 {
58 	return container_of(dssdev, struct dpi_data, output);
59 }
60 
61 static enum dss_clk_source dpi_get_clk_src_dra7xx(struct dpi_data *dpi,
62 						  enum omap_channel channel)
63 {
64 	/*
65 	 * Possible clock sources:
66 	 * LCD1: FCK/PLL1_1/HDMI_PLL
67 	 * LCD2: FCK/PLL1_3/HDMI_PLL (DRA74x: PLL2_3)
68 	 * LCD3: FCK/PLL1_3/HDMI_PLL (DRA74x: PLL2_1)
69 	 */
70 
71 	switch (channel) {
72 	case OMAP_DSS_CHANNEL_LCD:
73 	{
74 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL1_1))
75 			return DSS_CLK_SRC_PLL1_1;
76 		break;
77 	}
78 	case OMAP_DSS_CHANNEL_LCD2:
79 	{
80 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL1_3))
81 			return DSS_CLK_SRC_PLL1_3;
82 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL2_3))
83 			return DSS_CLK_SRC_PLL2_3;
84 		break;
85 	}
86 	case OMAP_DSS_CHANNEL_LCD3:
87 	{
88 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL2_1))
89 			return DSS_CLK_SRC_PLL2_1;
90 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL1_3))
91 			return DSS_CLK_SRC_PLL1_3;
92 		break;
93 	}
94 	default:
95 		break;
96 	}
97 
98 	return DSS_CLK_SRC_FCK;
99 }
100 
101 static enum dss_clk_source dpi_get_clk_src(struct dpi_data *dpi)
102 {
103 	enum omap_channel channel = dpi->output.dispc_channel;
104 
105 	/*
106 	 * XXX we can't currently use DSI PLL for DPI with OMAP3, as the DSI PLL
107 	 * would also be used for DISPC fclk. Meaning, when the DPI output is
108 	 * disabled, DISPC clock will be disabled, and TV out will stop.
109 	 */
110 	switch (dpi->dss_model) {
111 	case DSS_MODEL_OMAP2:
112 	case DSS_MODEL_OMAP3:
113 		return DSS_CLK_SRC_FCK;
114 
115 	case DSS_MODEL_OMAP4:
116 		switch (channel) {
117 		case OMAP_DSS_CHANNEL_LCD:
118 			return DSS_CLK_SRC_PLL1_1;
119 		case OMAP_DSS_CHANNEL_LCD2:
120 			return DSS_CLK_SRC_PLL2_1;
121 		default:
122 			return DSS_CLK_SRC_FCK;
123 		}
124 
125 	case DSS_MODEL_OMAP5:
126 		switch (channel) {
127 		case OMAP_DSS_CHANNEL_LCD:
128 			return DSS_CLK_SRC_PLL1_1;
129 		case OMAP_DSS_CHANNEL_LCD3:
130 			return DSS_CLK_SRC_PLL2_1;
131 		case OMAP_DSS_CHANNEL_LCD2:
132 		default:
133 			return DSS_CLK_SRC_FCK;
134 		}
135 
136 	case DSS_MODEL_DRA7:
137 		return dpi_get_clk_src_dra7xx(dpi, channel);
138 
139 	default:
140 		return DSS_CLK_SRC_FCK;
141 	}
142 }
143 
144 struct dpi_clk_calc_ctx {
145 	struct dpi_data *dpi;
146 	unsigned int clkout_idx;
147 
148 	/* inputs */
149 
150 	unsigned long pck_min, pck_max;
151 
152 	/* outputs */
153 
154 	struct dss_pll_clock_info pll_cinfo;
155 	unsigned long fck;
156 	struct dispc_clock_info dispc_cinfo;
157 };
158 
159 static bool dpi_calc_dispc_cb(int lckd, int pckd, unsigned long lck,
160 		unsigned long pck, void *data)
161 {
162 	struct dpi_clk_calc_ctx *ctx = data;
163 
164 	/*
165 	 * Odd dividers give us uneven duty cycle, causing problem when level
166 	 * shifted. So skip all odd dividers when the pixel clock is on the
167 	 * higher side.
168 	 */
169 	if (ctx->pck_min >= 100000000) {
170 		if (lckd > 1 && lckd % 2 != 0)
171 			return false;
172 
173 		if (pckd > 1 && pckd % 2 != 0)
174 			return false;
175 	}
176 
177 	ctx->dispc_cinfo.lck_div = lckd;
178 	ctx->dispc_cinfo.pck_div = pckd;
179 	ctx->dispc_cinfo.lck = lck;
180 	ctx->dispc_cinfo.pck = pck;
181 
182 	return true;
183 }
184 
185 
186 static bool dpi_calc_hsdiv_cb(int m_dispc, unsigned long dispc,
187 		void *data)
188 {
189 	struct dpi_clk_calc_ctx *ctx = data;
190 
191 	ctx->pll_cinfo.mX[ctx->clkout_idx] = m_dispc;
192 	ctx->pll_cinfo.clkout[ctx->clkout_idx] = dispc;
193 
194 	return dispc_div_calc(ctx->dpi->dss->dispc, dispc,
195 			      ctx->pck_min, ctx->pck_max,
196 			      dpi_calc_dispc_cb, ctx);
197 }
198 
199 
200 static bool dpi_calc_pll_cb(int n, int m, unsigned long fint,
201 		unsigned long clkdco,
202 		void *data)
203 {
204 	struct dpi_clk_calc_ctx *ctx = data;
205 
206 	ctx->pll_cinfo.n = n;
207 	ctx->pll_cinfo.m = m;
208 	ctx->pll_cinfo.fint = fint;
209 	ctx->pll_cinfo.clkdco = clkdco;
210 
211 	return dss_pll_hsdiv_calc_a(ctx->dpi->pll, clkdco,
212 		ctx->pck_min, dss_get_max_fck_rate(ctx->dpi->dss),
213 		dpi_calc_hsdiv_cb, ctx);
214 }
215 
216 static bool dpi_calc_dss_cb(unsigned long fck, void *data)
217 {
218 	struct dpi_clk_calc_ctx *ctx = data;
219 
220 	ctx->fck = fck;
221 
222 	return dispc_div_calc(ctx->dpi->dss->dispc, fck,
223 			      ctx->pck_min, ctx->pck_max,
224 			      dpi_calc_dispc_cb, ctx);
225 }
226 
227 static bool dpi_pll_clk_calc(struct dpi_data *dpi, unsigned long pck,
228 		struct dpi_clk_calc_ctx *ctx)
229 {
230 	unsigned long clkin;
231 
232 	memset(ctx, 0, sizeof(*ctx));
233 	ctx->dpi = dpi;
234 	ctx->clkout_idx = dss_pll_get_clkout_idx_for_src(dpi->clk_src);
235 
236 	clkin = clk_get_rate(dpi->pll->clkin);
237 
238 	if (dpi->pll->hw->type == DSS_PLL_TYPE_A) {
239 		unsigned long pll_min, pll_max;
240 
241 		ctx->pck_min = pck - 1000;
242 		ctx->pck_max = pck + 1000;
243 
244 		pll_min = 0;
245 		pll_max = 0;
246 
247 		return dss_pll_calc_a(ctx->dpi->pll, clkin,
248 				pll_min, pll_max,
249 				dpi_calc_pll_cb, ctx);
250 	} else { /* DSS_PLL_TYPE_B */
251 		dss_pll_calc_b(dpi->pll, clkin, pck, &ctx->pll_cinfo);
252 
253 		ctx->dispc_cinfo.lck_div = 1;
254 		ctx->dispc_cinfo.pck_div = 1;
255 		ctx->dispc_cinfo.lck = ctx->pll_cinfo.clkout[0];
256 		ctx->dispc_cinfo.pck = ctx->dispc_cinfo.lck;
257 
258 		return true;
259 	}
260 }
261 
262 static bool dpi_dss_clk_calc(struct dpi_data *dpi, unsigned long pck,
263 			     struct dpi_clk_calc_ctx *ctx)
264 {
265 	int i;
266 
267 	/*
268 	 * DSS fck gives us very few possibilities, so finding a good pixel
269 	 * clock may not be possible. We try multiple times to find the clock,
270 	 * each time widening the pixel clock range we look for, up to
271 	 * +/- ~15MHz.
272 	 */
273 
274 	for (i = 0; i < 25; ++i) {
275 		bool ok;
276 
277 		memset(ctx, 0, sizeof(*ctx));
278 		ctx->dpi = dpi;
279 		if (pck > 1000 * i * i * i)
280 			ctx->pck_min = max(pck - 1000 * i * i * i, 0lu);
281 		else
282 			ctx->pck_min = 0;
283 		ctx->pck_max = pck + 1000 * i * i * i;
284 
285 		ok = dss_div_calc(dpi->dss, pck, ctx->pck_min,
286 				  dpi_calc_dss_cb, ctx);
287 		if (ok)
288 			return ok;
289 	}
290 
291 	return false;
292 }
293 
294 
295 
296 static int dpi_set_pll_clk(struct dpi_data *dpi, enum omap_channel channel,
297 		unsigned long pck_req, unsigned long *fck, int *lck_div,
298 		int *pck_div)
299 {
300 	struct dpi_clk_calc_ctx ctx;
301 	int r;
302 	bool ok;
303 
304 	ok = dpi_pll_clk_calc(dpi, pck_req, &ctx);
305 	if (!ok)
306 		return -EINVAL;
307 
308 	r = dss_pll_set_config(dpi->pll, &ctx.pll_cinfo);
309 	if (r)
310 		return r;
311 
312 	dss_select_lcd_clk_source(dpi->dss, channel, dpi->clk_src);
313 
314 	dpi->mgr_config.clock_info = ctx.dispc_cinfo;
315 
316 	*fck = ctx.pll_cinfo.clkout[ctx.clkout_idx];
317 	*lck_div = ctx.dispc_cinfo.lck_div;
318 	*pck_div = ctx.dispc_cinfo.pck_div;
319 
320 	return 0;
321 }
322 
323 static int dpi_set_dispc_clk(struct dpi_data *dpi, unsigned long pck_req,
324 		unsigned long *fck, int *lck_div, int *pck_div)
325 {
326 	struct dpi_clk_calc_ctx ctx;
327 	int r;
328 	bool ok;
329 
330 	ok = dpi_dss_clk_calc(dpi, pck_req, &ctx);
331 	if (!ok)
332 		return -EINVAL;
333 
334 	r = dss_set_fck_rate(dpi->dss, ctx.fck);
335 	if (r)
336 		return r;
337 
338 	dpi->mgr_config.clock_info = ctx.dispc_cinfo;
339 
340 	*fck = ctx.fck;
341 	*lck_div = ctx.dispc_cinfo.lck_div;
342 	*pck_div = ctx.dispc_cinfo.pck_div;
343 
344 	return 0;
345 }
346 
347 static int dpi_set_mode(struct dpi_data *dpi)
348 {
349 	struct videomode *vm = &dpi->vm;
350 	int lck_div = 0, pck_div = 0;
351 	unsigned long fck = 0;
352 	unsigned long pck;
353 	int r = 0;
354 
355 	if (dpi->pll)
356 		r = dpi_set_pll_clk(dpi, dpi->output.dispc_channel,
357 				    vm->pixelclock, &fck, &lck_div, &pck_div);
358 	else
359 		r = dpi_set_dispc_clk(dpi, vm->pixelclock, &fck,
360 				&lck_div, &pck_div);
361 	if (r)
362 		return r;
363 
364 	pck = fck / lck_div / pck_div;
365 
366 	if (pck != vm->pixelclock) {
367 		DSSWARN("Could not find exact pixel clock. Requested %lu Hz, got %lu Hz\n",
368 			vm->pixelclock, pck);
369 
370 		vm->pixelclock = pck;
371 	}
372 
373 	dss_mgr_set_timings(&dpi->output, vm);
374 
375 	return 0;
376 }
377 
378 static void dpi_config_lcd_manager(struct dpi_data *dpi)
379 {
380 	dpi->mgr_config.io_pad_mode = DSS_IO_PAD_MODE_BYPASS;
381 
382 	dpi->mgr_config.stallmode = false;
383 	dpi->mgr_config.fifohandcheck = false;
384 
385 	dpi->mgr_config.video_port_width = dpi->data_lines;
386 
387 	dpi->mgr_config.lcden_sig_polarity = 0;
388 
389 	dss_mgr_set_lcd_config(&dpi->output, &dpi->mgr_config);
390 }
391 
392 static int dpi_display_enable(struct omap_dss_device *dssdev)
393 {
394 	struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
395 	struct omap_dss_device *out = &dpi->output;
396 	int r;
397 
398 	mutex_lock(&dpi->lock);
399 
400 	if (!out->dispc_channel_connected) {
401 		DSSERR("failed to enable display: no output/manager\n");
402 		r = -ENODEV;
403 		goto err_no_out_mgr;
404 	}
405 
406 	if (dpi->vdds_dsi_reg) {
407 		r = regulator_enable(dpi->vdds_dsi_reg);
408 		if (r)
409 			goto err_reg_enable;
410 	}
411 
412 	r = dispc_runtime_get(dpi->dss->dispc);
413 	if (r)
414 		goto err_get_dispc;
415 
416 	r = dss_dpi_select_source(dpi->dss, out->port_num, out->dispc_channel);
417 	if (r)
418 		goto err_src_sel;
419 
420 	if (dpi->pll) {
421 		r = dss_pll_enable(dpi->pll);
422 		if (r)
423 			goto err_pll_init;
424 	}
425 
426 	r = dpi_set_mode(dpi);
427 	if (r)
428 		goto err_set_mode;
429 
430 	dpi_config_lcd_manager(dpi);
431 
432 	mdelay(2);
433 
434 	r = dss_mgr_enable(&dpi->output);
435 	if (r)
436 		goto err_mgr_enable;
437 
438 	mutex_unlock(&dpi->lock);
439 
440 	return 0;
441 
442 err_mgr_enable:
443 err_set_mode:
444 	if (dpi->pll)
445 		dss_pll_disable(dpi->pll);
446 err_pll_init:
447 err_src_sel:
448 	dispc_runtime_put(dpi->dss->dispc);
449 err_get_dispc:
450 	if (dpi->vdds_dsi_reg)
451 		regulator_disable(dpi->vdds_dsi_reg);
452 err_reg_enable:
453 err_no_out_mgr:
454 	mutex_unlock(&dpi->lock);
455 	return r;
456 }
457 
458 static void dpi_display_disable(struct omap_dss_device *dssdev)
459 {
460 	struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
461 
462 	mutex_lock(&dpi->lock);
463 
464 	dss_mgr_disable(&dpi->output);
465 
466 	if (dpi->pll) {
467 		dss_select_lcd_clk_source(dpi->dss, dpi->output.dispc_channel,
468 					  DSS_CLK_SRC_FCK);
469 		dss_pll_disable(dpi->pll);
470 	}
471 
472 	dispc_runtime_put(dpi->dss->dispc);
473 
474 	if (dpi->vdds_dsi_reg)
475 		regulator_disable(dpi->vdds_dsi_reg);
476 
477 	mutex_unlock(&dpi->lock);
478 }
479 
480 static void dpi_set_timings(struct omap_dss_device *dssdev,
481 			    struct videomode *vm)
482 {
483 	struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
484 
485 	DSSDBG("dpi_set_timings\n");
486 
487 	mutex_lock(&dpi->lock);
488 
489 	dpi->vm = *vm;
490 
491 	mutex_unlock(&dpi->lock);
492 }
493 
494 static void dpi_get_timings(struct omap_dss_device *dssdev,
495 			    struct videomode *vm)
496 {
497 	struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
498 
499 	mutex_lock(&dpi->lock);
500 
501 	*vm = dpi->vm;
502 
503 	mutex_unlock(&dpi->lock);
504 }
505 
506 static int dpi_check_timings(struct omap_dss_device *dssdev,
507 			     struct videomode *vm)
508 {
509 	struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
510 	enum omap_channel channel = dpi->output.dispc_channel;
511 	int lck_div, pck_div;
512 	unsigned long fck;
513 	unsigned long pck;
514 	struct dpi_clk_calc_ctx ctx;
515 	bool ok;
516 
517 	if (vm->hactive % 8 != 0)
518 		return -EINVAL;
519 
520 	if (!dispc_mgr_timings_ok(dpi->dss->dispc, channel, vm))
521 		return -EINVAL;
522 
523 	if (vm->pixelclock == 0)
524 		return -EINVAL;
525 
526 	if (dpi->pll) {
527 		ok = dpi_pll_clk_calc(dpi, vm->pixelclock, &ctx);
528 		if (!ok)
529 			return -EINVAL;
530 
531 		fck = ctx.pll_cinfo.clkout[ctx.clkout_idx];
532 	} else {
533 		ok = dpi_dss_clk_calc(dpi, vm->pixelclock, &ctx);
534 		if (!ok)
535 			return -EINVAL;
536 
537 		fck = ctx.fck;
538 	}
539 
540 	lck_div = ctx.dispc_cinfo.lck_div;
541 	pck_div = ctx.dispc_cinfo.pck_div;
542 
543 	pck = fck / lck_div / pck_div;
544 
545 	vm->pixelclock = pck;
546 
547 	return 0;
548 }
549 
550 static int dpi_verify_pll(struct dss_pll *pll)
551 {
552 	int r;
553 
554 	/* do initial setup with the PLL to see if it is operational */
555 
556 	r = dss_pll_enable(pll);
557 	if (r)
558 		return r;
559 
560 	dss_pll_disable(pll);
561 
562 	return 0;
563 }
564 
565 static const struct soc_device_attribute dpi_soc_devices[] = {
566 	{ .machine = "OMAP3[456]*" },
567 	{ .machine = "[AD]M37*" },
568 	{ /* sentinel */ }
569 };
570 
571 static int dpi_init_regulator(struct dpi_data *dpi)
572 {
573 	struct regulator *vdds_dsi;
574 
575 	/*
576 	 * The DPI uses the DSI VDDS on OMAP34xx, OMAP35xx, OMAP36xx, AM37xx and
577 	 * DM37xx only.
578 	 */
579 	if (!soc_device_match(dpi_soc_devices))
580 		return 0;
581 
582 	if (dpi->vdds_dsi_reg)
583 		return 0;
584 
585 	vdds_dsi = devm_regulator_get(&dpi->pdev->dev, "vdds_dsi");
586 	if (IS_ERR(vdds_dsi)) {
587 		if (PTR_ERR(vdds_dsi) != -EPROBE_DEFER)
588 			DSSERR("can't get VDDS_DSI regulator\n");
589 		return PTR_ERR(vdds_dsi);
590 	}
591 
592 	dpi->vdds_dsi_reg = vdds_dsi;
593 
594 	return 0;
595 }
596 
597 static void dpi_init_pll(struct dpi_data *dpi)
598 {
599 	struct dss_pll *pll;
600 
601 	if (dpi->pll)
602 		return;
603 
604 	dpi->clk_src = dpi_get_clk_src(dpi);
605 
606 	pll = dss_pll_find_by_src(dpi->dss, dpi->clk_src);
607 	if (!pll)
608 		return;
609 
610 	if (dpi_verify_pll(pll)) {
611 		DSSWARN("PLL not operational\n");
612 		return;
613 	}
614 
615 	dpi->pll = pll;
616 }
617 
618 /*
619  * Return a hardcoded channel for the DPI output. This should work for
620  * current use cases, but this can be later expanded to either resolve
621  * the channel in some more dynamic manner, or get the channel as a user
622  * parameter.
623  */
624 static enum omap_channel dpi_get_channel(struct dpi_data *dpi, int port_num)
625 {
626 	switch (dpi->dss_model) {
627 	case DSS_MODEL_OMAP2:
628 	case DSS_MODEL_OMAP3:
629 		return OMAP_DSS_CHANNEL_LCD;
630 
631 	case DSS_MODEL_DRA7:
632 		switch (port_num) {
633 		case 2:
634 			return OMAP_DSS_CHANNEL_LCD3;
635 		case 1:
636 			return OMAP_DSS_CHANNEL_LCD2;
637 		case 0:
638 		default:
639 			return OMAP_DSS_CHANNEL_LCD;
640 		}
641 
642 	case DSS_MODEL_OMAP4:
643 		return OMAP_DSS_CHANNEL_LCD2;
644 
645 	case DSS_MODEL_OMAP5:
646 		return OMAP_DSS_CHANNEL_LCD3;
647 
648 	default:
649 		DSSWARN("unsupported DSS version\n");
650 		return OMAP_DSS_CHANNEL_LCD;
651 	}
652 }
653 
654 static int dpi_connect(struct omap_dss_device *dssdev,
655 		struct omap_dss_device *dst)
656 {
657 	struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
658 	int r;
659 
660 	r = dpi_init_regulator(dpi);
661 	if (r)
662 		return r;
663 
664 	dpi_init_pll(dpi);
665 
666 	r = dss_mgr_connect(&dpi->output, dssdev);
667 	if (r)
668 		return r;
669 
670 	r = omapdss_output_set_device(dssdev, dst);
671 	if (r) {
672 		DSSERR("failed to connect output to new device: %s\n",
673 				dst->name);
674 		dss_mgr_disconnect(&dpi->output, dssdev);
675 		return r;
676 	}
677 
678 	return 0;
679 }
680 
681 static void dpi_disconnect(struct omap_dss_device *dssdev,
682 		struct omap_dss_device *dst)
683 {
684 	struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
685 
686 	WARN_ON(dst != dssdev->dst);
687 
688 	if (dst != dssdev->dst)
689 		return;
690 
691 	omapdss_output_unset_device(dssdev);
692 
693 	dss_mgr_disconnect(&dpi->output, dssdev);
694 }
695 
696 static const struct omapdss_dpi_ops dpi_ops = {
697 	.connect = dpi_connect,
698 	.disconnect = dpi_disconnect,
699 
700 	.enable = dpi_display_enable,
701 	.disable = dpi_display_disable,
702 
703 	.check_timings = dpi_check_timings,
704 	.set_timings = dpi_set_timings,
705 	.get_timings = dpi_get_timings,
706 };
707 
708 static void dpi_init_output_port(struct dpi_data *dpi, struct device_node *port)
709 {
710 	struct omap_dss_device *out = &dpi->output;
711 	int r;
712 	u32 port_num;
713 
714 	r = of_property_read_u32(port, "reg", &port_num);
715 	if (r)
716 		port_num = 0;
717 
718 	switch (port_num) {
719 	case 2:
720 		out->name = "dpi.2";
721 		break;
722 	case 1:
723 		out->name = "dpi.1";
724 		break;
725 	case 0:
726 	default:
727 		out->name = "dpi.0";
728 		break;
729 	}
730 
731 	out->dev = &dpi->pdev->dev;
732 	out->id = OMAP_DSS_OUTPUT_DPI;
733 	out->output_type = OMAP_DISPLAY_TYPE_DPI;
734 	out->dispc_channel = dpi_get_channel(dpi, port_num);
735 	out->port_num = port_num;
736 	out->ops.dpi = &dpi_ops;
737 	out->owner = THIS_MODULE;
738 
739 	omapdss_register_output(out);
740 }
741 
742 static void dpi_uninit_output_port(struct device_node *port)
743 {
744 	struct dpi_data *dpi = port->data;
745 	struct omap_dss_device *out = &dpi->output;
746 
747 	omapdss_unregister_output(out);
748 }
749 
750 int dpi_init_port(struct dss_device *dss, struct platform_device *pdev,
751 		  struct device_node *port, enum dss_model dss_model)
752 {
753 	struct dpi_data *dpi;
754 	struct device_node *ep;
755 	u32 datalines;
756 	int r;
757 
758 	dpi = devm_kzalloc(&pdev->dev, sizeof(*dpi), GFP_KERNEL);
759 	if (!dpi)
760 		return -ENOMEM;
761 
762 	ep = of_get_next_child(port, NULL);
763 	if (!ep)
764 		return 0;
765 
766 	r = of_property_read_u32(ep, "data-lines", &datalines);
767 	if (r) {
768 		DSSERR("failed to parse datalines\n");
769 		goto err_datalines;
770 	}
771 
772 	dpi->data_lines = datalines;
773 
774 	of_node_put(ep);
775 
776 	dpi->pdev = pdev;
777 	dpi->dss_model = dss_model;
778 	dpi->dss = dss;
779 	port->data = dpi;
780 
781 	mutex_init(&dpi->lock);
782 
783 	dpi_init_output_port(dpi, port);
784 
785 	return 0;
786 
787 err_datalines:
788 	of_node_put(ep);
789 
790 	return r;
791 }
792 
793 void dpi_uninit_port(struct device_node *port)
794 {
795 	struct dpi_data *dpi = port->data;
796 
797 	if (!dpi)
798 		return;
799 
800 	dpi_uninit_output_port(port);
801 }
802