xref: /linux/drivers/gpu/drm/omapdrm/dss/dpi.c (revision fcc79e1714e8c2b8e216dc3149812edd37884eef)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2009 Nokia Corporation
4  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
5  *
6  * Some code and ideas taken from drivers/video/omap/ driver
7  * by Imre Deak.
8  */
9 
10 #define DSS_SUBSYS_NAME "DPI"
11 
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/err.h>
15 #include <linux/errno.h>
16 #include <linux/export.h>
17 #include <linux/kernel.h>
18 #include <linux/of.h>
19 #include <linux/of_graph.h>
20 #include <linux/platform_device.h>
21 #include <linux/regulator/consumer.h>
22 #include <linux/string.h>
23 #include <linux/sys_soc.h>
24 
25 #include <drm/drm_bridge.h>
26 
27 #include "dss.h"
28 #include "omapdss.h"
29 
30 struct dpi_data {
31 	struct platform_device *pdev;
32 	enum dss_model dss_model;
33 	struct dss_device *dss;
34 	unsigned int id;
35 
36 	struct regulator *vdds_dsi_reg;
37 	enum dss_clk_source clk_src;
38 	struct dss_pll *pll;
39 
40 	struct dss_lcd_mgr_config mgr_config;
41 	unsigned long pixelclock;
42 	int data_lines;
43 
44 	struct omap_dss_device output;
45 	struct drm_bridge bridge;
46 };
47 
48 #define drm_bridge_to_dpi(bridge) container_of(bridge, struct dpi_data, bridge)
49 
50 /* -----------------------------------------------------------------------------
51  * Clock Handling and PLL
52  */
53 
54 static enum dss_clk_source dpi_get_clk_src_dra7xx(struct dpi_data *dpi,
55 						  enum omap_channel channel)
56 {
57 	/*
58 	 * Possible clock sources:
59 	 * LCD1: FCK/PLL1_1/HDMI_PLL
60 	 * LCD2: FCK/PLL1_3/HDMI_PLL (DRA74x: PLL2_3)
61 	 * LCD3: FCK/PLL1_3/HDMI_PLL (DRA74x: PLL2_1)
62 	 */
63 
64 	switch (channel) {
65 	case OMAP_DSS_CHANNEL_LCD:
66 	{
67 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL1_1))
68 			return DSS_CLK_SRC_PLL1_1;
69 		break;
70 	}
71 	case OMAP_DSS_CHANNEL_LCD2:
72 	{
73 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL1_3))
74 			return DSS_CLK_SRC_PLL1_3;
75 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL2_3))
76 			return DSS_CLK_SRC_PLL2_3;
77 		break;
78 	}
79 	case OMAP_DSS_CHANNEL_LCD3:
80 	{
81 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL2_1))
82 			return DSS_CLK_SRC_PLL2_1;
83 		if (dss_pll_find_by_src(dpi->dss, DSS_CLK_SRC_PLL1_3))
84 			return DSS_CLK_SRC_PLL1_3;
85 		break;
86 	}
87 	default:
88 		break;
89 	}
90 
91 	return DSS_CLK_SRC_FCK;
92 }
93 
94 static enum dss_clk_source dpi_get_clk_src(struct dpi_data *dpi)
95 {
96 	enum omap_channel channel = dpi->output.dispc_channel;
97 
98 	/*
99 	 * XXX we can't currently use DSI PLL for DPI with OMAP3, as the DSI PLL
100 	 * would also be used for DISPC fclk. Meaning, when the DPI output is
101 	 * disabled, DISPC clock will be disabled, and TV out will stop.
102 	 */
103 	switch (dpi->dss_model) {
104 	case DSS_MODEL_OMAP2:
105 	case DSS_MODEL_OMAP3:
106 		return DSS_CLK_SRC_FCK;
107 
108 	case DSS_MODEL_OMAP4:
109 		switch (channel) {
110 		case OMAP_DSS_CHANNEL_LCD:
111 			return DSS_CLK_SRC_PLL1_1;
112 		case OMAP_DSS_CHANNEL_LCD2:
113 			return DSS_CLK_SRC_PLL2_1;
114 		default:
115 			return DSS_CLK_SRC_FCK;
116 		}
117 
118 	case DSS_MODEL_OMAP5:
119 		switch (channel) {
120 		case OMAP_DSS_CHANNEL_LCD:
121 			return DSS_CLK_SRC_PLL1_1;
122 		case OMAP_DSS_CHANNEL_LCD3:
123 			return DSS_CLK_SRC_PLL2_1;
124 		case OMAP_DSS_CHANNEL_LCD2:
125 		default:
126 			return DSS_CLK_SRC_FCK;
127 		}
128 
129 	case DSS_MODEL_DRA7:
130 		return dpi_get_clk_src_dra7xx(dpi, channel);
131 
132 	default:
133 		return DSS_CLK_SRC_FCK;
134 	}
135 }
136 
137 struct dpi_clk_calc_ctx {
138 	struct dpi_data *dpi;
139 	unsigned int clkout_idx;
140 
141 	/* inputs */
142 
143 	unsigned long pck_min, pck_max;
144 
145 	/* outputs */
146 
147 	struct dss_pll_clock_info pll_cinfo;
148 	unsigned long fck;
149 	struct dispc_clock_info dispc_cinfo;
150 };
151 
152 static bool dpi_calc_dispc_cb(int lckd, int pckd, unsigned long lck,
153 		unsigned long pck, void *data)
154 {
155 	struct dpi_clk_calc_ctx *ctx = data;
156 
157 	/*
158 	 * Odd dividers give us uneven duty cycle, causing problem when level
159 	 * shifted. So skip all odd dividers when the pixel clock is on the
160 	 * higher side.
161 	 */
162 	if (ctx->pck_min >= 100000000) {
163 		if (lckd > 1 && lckd % 2 != 0)
164 			return false;
165 
166 		if (pckd > 1 && pckd % 2 != 0)
167 			return false;
168 	}
169 
170 	ctx->dispc_cinfo.lck_div = lckd;
171 	ctx->dispc_cinfo.pck_div = pckd;
172 	ctx->dispc_cinfo.lck = lck;
173 	ctx->dispc_cinfo.pck = pck;
174 
175 	return true;
176 }
177 
178 
179 static bool dpi_calc_hsdiv_cb(int m_dispc, unsigned long dispc,
180 		void *data)
181 {
182 	struct dpi_clk_calc_ctx *ctx = data;
183 
184 	ctx->pll_cinfo.mX[ctx->clkout_idx] = m_dispc;
185 	ctx->pll_cinfo.clkout[ctx->clkout_idx] = dispc;
186 
187 	return dispc_div_calc(ctx->dpi->dss->dispc, dispc,
188 			      ctx->pck_min, ctx->pck_max,
189 			      dpi_calc_dispc_cb, ctx);
190 }
191 
192 
193 static bool dpi_calc_pll_cb(int n, int m, unsigned long fint,
194 		unsigned long clkdco,
195 		void *data)
196 {
197 	struct dpi_clk_calc_ctx *ctx = data;
198 
199 	ctx->pll_cinfo.n = n;
200 	ctx->pll_cinfo.m = m;
201 	ctx->pll_cinfo.fint = fint;
202 	ctx->pll_cinfo.clkdco = clkdco;
203 
204 	return dss_pll_hsdiv_calc_a(ctx->dpi->pll, clkdco,
205 		ctx->pck_min, dss_get_max_fck_rate(ctx->dpi->dss),
206 		dpi_calc_hsdiv_cb, ctx);
207 }
208 
209 static bool dpi_calc_dss_cb(unsigned long fck, void *data)
210 {
211 	struct dpi_clk_calc_ctx *ctx = data;
212 
213 	ctx->fck = fck;
214 
215 	return dispc_div_calc(ctx->dpi->dss->dispc, fck,
216 			      ctx->pck_min, ctx->pck_max,
217 			      dpi_calc_dispc_cb, ctx);
218 }
219 
220 static bool dpi_pll_clk_calc(struct dpi_data *dpi, unsigned long pck,
221 		struct dpi_clk_calc_ctx *ctx)
222 {
223 	unsigned long clkin;
224 
225 	memset(ctx, 0, sizeof(*ctx));
226 	ctx->dpi = dpi;
227 	ctx->clkout_idx = dss_pll_get_clkout_idx_for_src(dpi->clk_src);
228 
229 	clkin = clk_get_rate(dpi->pll->clkin);
230 
231 	if (dpi->pll->hw->type == DSS_PLL_TYPE_A) {
232 		unsigned long pll_min, pll_max;
233 
234 		ctx->pck_min = pck - 1000;
235 		ctx->pck_max = pck + 1000;
236 
237 		pll_min = 0;
238 		pll_max = 0;
239 
240 		return dss_pll_calc_a(ctx->dpi->pll, clkin,
241 				pll_min, pll_max,
242 				dpi_calc_pll_cb, ctx);
243 	} else { /* DSS_PLL_TYPE_B */
244 		dss_pll_calc_b(dpi->pll, clkin, pck, &ctx->pll_cinfo);
245 
246 		ctx->dispc_cinfo.lck_div = 1;
247 		ctx->dispc_cinfo.pck_div = 1;
248 		ctx->dispc_cinfo.lck = ctx->pll_cinfo.clkout[0];
249 		ctx->dispc_cinfo.pck = ctx->dispc_cinfo.lck;
250 
251 		return true;
252 	}
253 }
254 
255 static bool dpi_dss_clk_calc(struct dpi_data *dpi, unsigned long pck,
256 			     struct dpi_clk_calc_ctx *ctx)
257 {
258 	int i;
259 
260 	/*
261 	 * DSS fck gives us very few possibilities, so finding a good pixel
262 	 * clock may not be possible. We try multiple times to find the clock,
263 	 * each time widening the pixel clock range we look for, up to
264 	 * +/- ~15MHz.
265 	 */
266 
267 	for (i = 0; i < 25; ++i) {
268 		bool ok;
269 
270 		memset(ctx, 0, sizeof(*ctx));
271 		ctx->dpi = dpi;
272 		if (pck > 1000 * i * i * i)
273 			ctx->pck_min = max(pck - 1000 * i * i * i, 0lu);
274 		else
275 			ctx->pck_min = 0;
276 		ctx->pck_max = pck + 1000 * i * i * i;
277 
278 		ok = dss_div_calc(dpi->dss, pck, ctx->pck_min,
279 				  dpi_calc_dss_cb, ctx);
280 		if (ok)
281 			return ok;
282 	}
283 
284 	return false;
285 }
286 
287 
288 
289 static int dpi_set_pll_clk(struct dpi_data *dpi, unsigned long pck_req)
290 {
291 	struct dpi_clk_calc_ctx ctx;
292 	int r;
293 	bool ok;
294 
295 	ok = dpi_pll_clk_calc(dpi, pck_req, &ctx);
296 	if (!ok)
297 		return -EINVAL;
298 
299 	r = dss_pll_set_config(dpi->pll, &ctx.pll_cinfo);
300 	if (r)
301 		return r;
302 
303 	dss_select_lcd_clk_source(dpi->dss, dpi->output.dispc_channel,
304 				  dpi->clk_src);
305 
306 	dpi->mgr_config.clock_info = ctx.dispc_cinfo;
307 
308 	return 0;
309 }
310 
311 static int dpi_set_dispc_clk(struct dpi_data *dpi, unsigned long pck_req)
312 {
313 	struct dpi_clk_calc_ctx ctx;
314 	int r;
315 	bool ok;
316 
317 	ok = dpi_dss_clk_calc(dpi, pck_req, &ctx);
318 	if (!ok)
319 		return -EINVAL;
320 
321 	r = dss_set_fck_rate(dpi->dss, ctx.fck);
322 	if (r)
323 		return r;
324 
325 	dpi->mgr_config.clock_info = ctx.dispc_cinfo;
326 
327 	return 0;
328 }
329 
330 static int dpi_set_mode(struct dpi_data *dpi)
331 {
332 	int r;
333 
334 	if (dpi->pll)
335 		r = dpi_set_pll_clk(dpi, dpi->pixelclock);
336 	else
337 		r = dpi_set_dispc_clk(dpi, dpi->pixelclock);
338 
339 	return r;
340 }
341 
342 static void dpi_config_lcd_manager(struct dpi_data *dpi)
343 {
344 	dpi->mgr_config.io_pad_mode = DSS_IO_PAD_MODE_BYPASS;
345 
346 	dpi->mgr_config.stallmode = false;
347 	dpi->mgr_config.fifohandcheck = false;
348 
349 	dpi->mgr_config.video_port_width = dpi->data_lines;
350 
351 	dpi->mgr_config.lcden_sig_polarity = 0;
352 
353 	dss_mgr_set_lcd_config(&dpi->output, &dpi->mgr_config);
354 }
355 
356 static int dpi_clock_update(struct dpi_data *dpi, unsigned long *clock)
357 {
358 	int lck_div, pck_div;
359 	unsigned long fck;
360 	struct dpi_clk_calc_ctx ctx;
361 
362 	if (dpi->pll) {
363 		if (!dpi_pll_clk_calc(dpi, *clock, &ctx))
364 			return -EINVAL;
365 
366 		fck = ctx.pll_cinfo.clkout[ctx.clkout_idx];
367 	} else {
368 		if (!dpi_dss_clk_calc(dpi, *clock, &ctx))
369 			return -EINVAL;
370 
371 		fck = ctx.fck;
372 	}
373 
374 	lck_div = ctx.dispc_cinfo.lck_div;
375 	pck_div = ctx.dispc_cinfo.pck_div;
376 
377 	*clock = fck / lck_div / pck_div;
378 
379 	return 0;
380 }
381 
382 static int dpi_verify_pll(struct dss_pll *pll)
383 {
384 	int r;
385 
386 	/* do initial setup with the PLL to see if it is operational */
387 
388 	r = dss_pll_enable(pll);
389 	if (r)
390 		return r;
391 
392 	dss_pll_disable(pll);
393 
394 	return 0;
395 }
396 
397 static void dpi_init_pll(struct dpi_data *dpi)
398 {
399 	struct dss_pll *pll;
400 
401 	if (dpi->pll)
402 		return;
403 
404 	dpi->clk_src = dpi_get_clk_src(dpi);
405 
406 	pll = dss_pll_find_by_src(dpi->dss, dpi->clk_src);
407 	if (!pll)
408 		return;
409 
410 	if (dpi_verify_pll(pll)) {
411 		DSSWARN("PLL not operational\n");
412 		return;
413 	}
414 
415 	dpi->pll = pll;
416 }
417 
418 /* -----------------------------------------------------------------------------
419  * DRM Bridge Operations
420  */
421 
422 static int dpi_bridge_attach(struct drm_bridge *bridge,
423 			     enum drm_bridge_attach_flags flags)
424 {
425 	struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
426 
427 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
428 		return -EINVAL;
429 
430 	dpi_init_pll(dpi);
431 
432 	return drm_bridge_attach(bridge->encoder, dpi->output.next_bridge,
433 				 bridge, flags);
434 }
435 
436 static enum drm_mode_status
437 dpi_bridge_mode_valid(struct drm_bridge *bridge,
438 		       const struct drm_display_info *info,
439 		       const struct drm_display_mode *mode)
440 {
441 	struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
442 	unsigned long clock = mode->clock * 1000;
443 	int ret;
444 
445 	if (mode->hdisplay % 8 != 0)
446 		return MODE_BAD_WIDTH;
447 
448 	if (mode->clock == 0)
449 		return MODE_NOCLOCK;
450 
451 	ret = dpi_clock_update(dpi, &clock);
452 	if (ret < 0)
453 		return MODE_CLOCK_RANGE;
454 
455 	return MODE_OK;
456 }
457 
458 static bool dpi_bridge_mode_fixup(struct drm_bridge *bridge,
459 				   const struct drm_display_mode *mode,
460 				   struct drm_display_mode *adjusted_mode)
461 {
462 	struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
463 	unsigned long clock = mode->clock * 1000;
464 	int ret;
465 
466 	ret = dpi_clock_update(dpi, &clock);
467 	if (ret < 0)
468 		return false;
469 
470 	adjusted_mode->clock = clock / 1000;
471 
472 	return true;
473 }
474 
475 static void dpi_bridge_mode_set(struct drm_bridge *bridge,
476 				 const struct drm_display_mode *mode,
477 				 const struct drm_display_mode *adjusted_mode)
478 {
479 	struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
480 
481 	dpi->pixelclock = adjusted_mode->clock * 1000;
482 }
483 
484 static void dpi_bridge_enable(struct drm_bridge *bridge)
485 {
486 	struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
487 	int r;
488 
489 	if (dpi->vdds_dsi_reg) {
490 		r = regulator_enable(dpi->vdds_dsi_reg);
491 		if (r)
492 			return;
493 	}
494 
495 	r = dispc_runtime_get(dpi->dss->dispc);
496 	if (r)
497 		goto err_get_dispc;
498 
499 	r = dss_dpi_select_source(dpi->dss, dpi->id, dpi->output.dispc_channel);
500 	if (r)
501 		goto err_src_sel;
502 
503 	if (dpi->pll) {
504 		r = dss_pll_enable(dpi->pll);
505 		if (r)
506 			goto err_pll_init;
507 	}
508 
509 	r = dpi_set_mode(dpi);
510 	if (r)
511 		goto err_set_mode;
512 
513 	dpi_config_lcd_manager(dpi);
514 
515 	mdelay(2);
516 
517 	r = dss_mgr_enable(&dpi->output);
518 	if (r)
519 		goto err_mgr_enable;
520 
521 	return;
522 
523 err_mgr_enable:
524 err_set_mode:
525 	if (dpi->pll)
526 		dss_pll_disable(dpi->pll);
527 err_pll_init:
528 err_src_sel:
529 	dispc_runtime_put(dpi->dss->dispc);
530 err_get_dispc:
531 	if (dpi->vdds_dsi_reg)
532 		regulator_disable(dpi->vdds_dsi_reg);
533 }
534 
535 static void dpi_bridge_disable(struct drm_bridge *bridge)
536 {
537 	struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
538 
539 	dss_mgr_disable(&dpi->output);
540 
541 	if (dpi->pll) {
542 		dss_select_lcd_clk_source(dpi->dss, dpi->output.dispc_channel,
543 					  DSS_CLK_SRC_FCK);
544 		dss_pll_disable(dpi->pll);
545 	}
546 
547 	dispc_runtime_put(dpi->dss->dispc);
548 
549 	if (dpi->vdds_dsi_reg)
550 		regulator_disable(dpi->vdds_dsi_reg);
551 }
552 
553 static const struct drm_bridge_funcs dpi_bridge_funcs = {
554 	.attach = dpi_bridge_attach,
555 	.mode_valid = dpi_bridge_mode_valid,
556 	.mode_fixup = dpi_bridge_mode_fixup,
557 	.mode_set = dpi_bridge_mode_set,
558 	.enable = dpi_bridge_enable,
559 	.disable = dpi_bridge_disable,
560 };
561 
562 static void dpi_bridge_init(struct dpi_data *dpi)
563 {
564 	dpi->bridge.funcs = &dpi_bridge_funcs;
565 	dpi->bridge.of_node = dpi->pdev->dev.of_node;
566 	dpi->bridge.type = DRM_MODE_CONNECTOR_DPI;
567 
568 	drm_bridge_add(&dpi->bridge);
569 }
570 
571 static void dpi_bridge_cleanup(struct dpi_data *dpi)
572 {
573 	drm_bridge_remove(&dpi->bridge);
574 }
575 
576 /* -----------------------------------------------------------------------------
577  * Initialisation and Cleanup
578  */
579 
580 /*
581  * Return a hardcoded channel for the DPI output. This should work for
582  * current use cases, but this can be later expanded to either resolve
583  * the channel in some more dynamic manner, or get the channel as a user
584  * parameter.
585  */
586 static enum omap_channel dpi_get_channel(struct dpi_data *dpi)
587 {
588 	switch (dpi->dss_model) {
589 	case DSS_MODEL_OMAP2:
590 	case DSS_MODEL_OMAP3:
591 		return OMAP_DSS_CHANNEL_LCD;
592 
593 	case DSS_MODEL_DRA7:
594 		switch (dpi->id) {
595 		case 2:
596 			return OMAP_DSS_CHANNEL_LCD3;
597 		case 1:
598 			return OMAP_DSS_CHANNEL_LCD2;
599 		case 0:
600 		default:
601 			return OMAP_DSS_CHANNEL_LCD;
602 		}
603 
604 	case DSS_MODEL_OMAP4:
605 		return OMAP_DSS_CHANNEL_LCD2;
606 
607 	case DSS_MODEL_OMAP5:
608 		return OMAP_DSS_CHANNEL_LCD3;
609 
610 	default:
611 		DSSWARN("unsupported DSS version\n");
612 		return OMAP_DSS_CHANNEL_LCD;
613 	}
614 }
615 
616 static int dpi_init_output_port(struct dpi_data *dpi, struct device_node *port)
617 {
618 	struct omap_dss_device *out = &dpi->output;
619 	u32 port_num = 0;
620 	int r;
621 
622 	dpi_bridge_init(dpi);
623 
624 	of_property_read_u32(port, "reg", &port_num);
625 	dpi->id = port_num <= 2 ? port_num : 0;
626 
627 	switch (port_num) {
628 	case 2:
629 		out->name = "dpi.2";
630 		break;
631 	case 1:
632 		out->name = "dpi.1";
633 		break;
634 	case 0:
635 	default:
636 		out->name = "dpi.0";
637 		break;
638 	}
639 
640 	out->dev = &dpi->pdev->dev;
641 	out->id = OMAP_DSS_OUTPUT_DPI;
642 	out->type = OMAP_DISPLAY_TYPE_DPI;
643 	out->dispc_channel = dpi_get_channel(dpi);
644 	out->of_port = port_num;
645 
646 	r = omapdss_device_init_output(out, &dpi->bridge);
647 	if (r < 0) {
648 		dpi_bridge_cleanup(dpi);
649 		return r;
650 	}
651 
652 	omapdss_device_register(out);
653 
654 	return 0;
655 }
656 
657 static void dpi_uninit_output_port(struct device_node *port)
658 {
659 	struct dpi_data *dpi = port->data;
660 	struct omap_dss_device *out = &dpi->output;
661 
662 	omapdss_device_unregister(out);
663 	omapdss_device_cleanup_output(out);
664 
665 	dpi_bridge_cleanup(dpi);
666 }
667 
668 /* -----------------------------------------------------------------------------
669  * Initialisation and Cleanup
670  */
671 
672 static const struct soc_device_attribute dpi_soc_devices[] = {
673 	{ .machine = "OMAP3[456]*" },
674 	{ .machine = "[AD]M37*" },
675 	{ /* sentinel */ }
676 };
677 
678 static int dpi_init_regulator(struct dpi_data *dpi)
679 {
680 	struct regulator *vdds_dsi;
681 
682 	/*
683 	 * The DPI uses the DSI VDDS on OMAP34xx, OMAP35xx, OMAP36xx, AM37xx and
684 	 * DM37xx only.
685 	 */
686 	if (!soc_device_match(dpi_soc_devices))
687 		return 0;
688 
689 	vdds_dsi = devm_regulator_get(&dpi->pdev->dev, "vdds_dsi");
690 	if (IS_ERR(vdds_dsi)) {
691 		if (PTR_ERR(vdds_dsi) != -EPROBE_DEFER)
692 			DSSERR("can't get VDDS_DSI regulator\n");
693 		return PTR_ERR(vdds_dsi);
694 	}
695 
696 	dpi->vdds_dsi_reg = vdds_dsi;
697 
698 	return 0;
699 }
700 
701 int dpi_init_port(struct dss_device *dss, struct platform_device *pdev,
702 		  struct device_node *port, enum dss_model dss_model)
703 {
704 	struct dpi_data *dpi;
705 	struct device_node *ep;
706 	u32 datalines;
707 	int r;
708 
709 	dpi = devm_kzalloc(&pdev->dev, sizeof(*dpi), GFP_KERNEL);
710 	if (!dpi)
711 		return -ENOMEM;
712 
713 	ep = of_graph_get_next_port_endpoint(port, NULL);
714 	if (!ep)
715 		return 0;
716 
717 	r = of_property_read_u32(ep, "data-lines", &datalines);
718 	of_node_put(ep);
719 	if (r) {
720 		DSSERR("failed to parse datalines\n");
721 		return r;
722 	}
723 
724 	dpi->data_lines = datalines;
725 
726 	dpi->pdev = pdev;
727 	dpi->dss_model = dss_model;
728 	dpi->dss = dss;
729 	port->data = dpi;
730 
731 	r = dpi_init_regulator(dpi);
732 	if (r)
733 		return r;
734 
735 	return dpi_init_output_port(dpi, port);
736 }
737 
738 void dpi_uninit_port(struct device_node *port)
739 {
740 	struct dpi_data *dpi = port->data;
741 
742 	if (!dpi)
743 		return;
744 
745 	dpi_uninit_output_port(port);
746 }
747