1/*
2 * i.MX drm driver - LVDS display bridge
3 *
4 * Copyright (C) 2012 Sascha Hauer, Pengutronix
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/module.h>
17#include <linux/clk.h>
18#include <linux/component.h>
19#include <drm/drmP.h>
20#include <drm/drm_fb_helper.h>
21#include <drm/drm_crtc_helper.h>
22#include <drm/drm_panel.h>
23#include <linux/mfd/syscon.h>
24#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
25#include <linux/of_device.h>
26#include <linux/of_graph.h>
27#include <video/of_videomode.h>
28#include <linux/regmap.h>
29#include <linux/videodev2.h>
30
31#include "imx-drm.h"
32
33#define DRIVER_NAME "imx-ldb"
34
35#define LDB_CH0_MODE_EN_TO_DI0		(1 << 0)
36#define LDB_CH0_MODE_EN_TO_DI1		(3 << 0)
37#define LDB_CH0_MODE_EN_MASK		(3 << 0)
38#define LDB_CH1_MODE_EN_TO_DI0		(1 << 2)
39#define LDB_CH1_MODE_EN_TO_DI1		(3 << 2)
40#define LDB_CH1_MODE_EN_MASK		(3 << 2)
41#define LDB_SPLIT_MODE_EN		(1 << 4)
42#define LDB_DATA_WIDTH_CH0_24		(1 << 5)
43#define LDB_BIT_MAP_CH0_JEIDA		(1 << 6)
44#define LDB_DATA_WIDTH_CH1_24		(1 << 7)
45#define LDB_BIT_MAP_CH1_JEIDA		(1 << 8)
46#define LDB_DI0_VS_POL_ACT_LOW		(1 << 9)
47#define LDB_DI1_VS_POL_ACT_LOW		(1 << 10)
48#define LDB_BGREF_RMODE_INT		(1 << 15)
49
50#define con_to_imx_ldb_ch(x) container_of(x, struct imx_ldb_channel, connector)
51#define enc_to_imx_ldb_ch(x) container_of(x, struct imx_ldb_channel, encoder)
52
53struct imx_ldb;
54
55struct imx_ldb_channel {
56	struct imx_ldb *ldb;
57	struct drm_connector connector;
58	struct drm_encoder encoder;
59	struct drm_panel *panel;
60	struct device_node *child;
61	int chno;
62	void *edid;
63	int edid_len;
64	struct drm_display_mode mode;
65	int mode_valid;
66	int bus_format;
67};
68
69struct bus_mux {
70	int reg;
71	int shift;
72	int mask;
73};
74
75struct imx_ldb {
76	struct regmap *regmap;
77	struct device *dev;
78	struct imx_ldb_channel channel[2];
79	struct clk *clk[2]; /* our own clock */
80	struct clk *clk_sel[4]; /* parent of display clock */
81	struct clk *clk_parent[4]; /* original parent of clk_sel */
82	struct clk *clk_pll[2]; /* upstream clock we can adjust */
83	u32 ldb_ctrl;
84	const struct bus_mux *lvds_mux;
85};
86
87static enum drm_connector_status imx_ldb_connector_detect(
88		struct drm_connector *connector, bool force)
89{
90	return connector_status_connected;
91}
92
93static int imx_ldb_connector_get_modes(struct drm_connector *connector)
94{
95	struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
96	int num_modes = 0;
97
98	if (imx_ldb_ch->panel && imx_ldb_ch->panel->funcs &&
99	    imx_ldb_ch->panel->funcs->get_modes) {
100		struct drm_display_info *di = &connector->display_info;
101
102		num_modes = imx_ldb_ch->panel->funcs->get_modes(imx_ldb_ch->panel);
103		if (!imx_ldb_ch->bus_format && di->num_bus_formats)
104			imx_ldb_ch->bus_format = di->bus_formats[0];
105		if (num_modes > 0)
106			return num_modes;
107	}
108
109	if (imx_ldb_ch->edid) {
110		drm_mode_connector_update_edid_property(connector,
111							imx_ldb_ch->edid);
112		num_modes = drm_add_edid_modes(connector, imx_ldb_ch->edid);
113	}
114
115	if (imx_ldb_ch->mode_valid) {
116		struct drm_display_mode *mode;
117
118		mode = drm_mode_create(connector->dev);
119		if (!mode)
120			return -EINVAL;
121		drm_mode_copy(mode, &imx_ldb_ch->mode);
122		mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
123		drm_mode_probed_add(connector, mode);
124		num_modes++;
125	}
126
127	return num_modes;
128}
129
130static struct drm_encoder *imx_ldb_connector_best_encoder(
131		struct drm_connector *connector)
132{
133	struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
134
135	return &imx_ldb_ch->encoder;
136}
137
138static void imx_ldb_encoder_dpms(struct drm_encoder *encoder, int mode)
139{
140}
141
142static bool imx_ldb_encoder_mode_fixup(struct drm_encoder *encoder,
143			   const struct drm_display_mode *mode,
144			   struct drm_display_mode *adjusted_mode)
145{
146	return true;
147}
148
149static void imx_ldb_set_clock(struct imx_ldb *ldb, int mux, int chno,
150		unsigned long serial_clk, unsigned long di_clk)
151{
152	int ret;
153
154	dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
155			clk_get_rate(ldb->clk_pll[chno]), serial_clk);
156	clk_set_rate(ldb->clk_pll[chno], serial_clk);
157
158	dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
159			clk_get_rate(ldb->clk_pll[chno]));
160
161	dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
162			clk_get_rate(ldb->clk[chno]),
163			(long int)di_clk);
164	clk_set_rate(ldb->clk[chno], di_clk);
165
166	dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
167			clk_get_rate(ldb->clk[chno]));
168
169	/* set display clock mux to LDB input clock */
170	ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk[chno]);
171	if (ret)
172		dev_err(ldb->dev,
173			"unable to set di%d parent clock to ldb_di%d\n", mux,
174			chno);
175}
176
177static void imx_ldb_encoder_prepare(struct drm_encoder *encoder)
178{
179	struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
180	struct imx_ldb *ldb = imx_ldb_ch->ldb;
181	int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
182	u32 bus_format;
183
184	switch (imx_ldb_ch->bus_format) {
185	default:
186		dev_warn(ldb->dev,
187			 "could not determine data mapping, default to 18-bit \"spwg\"\n");
188		/* fallthrough */
189	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
190		bus_format = MEDIA_BUS_FMT_RGB666_1X18;
191		break;
192	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
193		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
194		if (imx_ldb_ch->chno == 0 || dual)
195			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24;
196		if (imx_ldb_ch->chno == 1 || dual)
197			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24;
198		break;
199	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
200		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
201		if (imx_ldb_ch->chno == 0 || dual)
202			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24 |
203					 LDB_BIT_MAP_CH0_JEIDA;
204		if (imx_ldb_ch->chno == 1 || dual)
205			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24 |
206					 LDB_BIT_MAP_CH1_JEIDA;
207		break;
208	}
209
210	imx_drm_set_bus_format(encoder, bus_format);
211}
212
213static void imx_ldb_encoder_commit(struct drm_encoder *encoder)
214{
215	struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
216	struct imx_ldb *ldb = imx_ldb_ch->ldb;
217	int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
218	int mux = imx_drm_encoder_get_mux_id(imx_ldb_ch->child, encoder);
219
220	drm_panel_prepare(imx_ldb_ch->panel);
221
222	if (dual) {
223		clk_prepare_enable(ldb->clk[0]);
224		clk_prepare_enable(ldb->clk[1]);
225	}
226
227	if (imx_ldb_ch == &ldb->channel[0] || dual) {
228		ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
229		if (mux == 0 || ldb->lvds_mux)
230			ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI0;
231		else if (mux == 1)
232			ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI1;
233	}
234	if (imx_ldb_ch == &ldb->channel[1] || dual) {
235		ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
236		if (mux == 1 || ldb->lvds_mux)
237			ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI1;
238		else if (mux == 0)
239			ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI0;
240	}
241
242	if (ldb->lvds_mux) {
243		const struct bus_mux *lvds_mux = NULL;
244
245		if (imx_ldb_ch == &ldb->channel[0])
246			lvds_mux = &ldb->lvds_mux[0];
247		else if (imx_ldb_ch == &ldb->channel[1])
248			lvds_mux = &ldb->lvds_mux[1];
249
250		regmap_update_bits(ldb->regmap, lvds_mux->reg, lvds_mux->mask,
251				   mux << lvds_mux->shift);
252	}
253
254	regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
255
256	drm_panel_enable(imx_ldb_ch->panel);
257}
258
259static void imx_ldb_encoder_mode_set(struct drm_encoder *encoder,
260			 struct drm_display_mode *orig_mode,
261			 struct drm_display_mode *mode)
262{
263	struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
264	struct imx_ldb *ldb = imx_ldb_ch->ldb;
265	int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
266	unsigned long serial_clk;
267	unsigned long di_clk = mode->clock * 1000;
268	int mux = imx_drm_encoder_get_mux_id(imx_ldb_ch->child, encoder);
269
270	if (mode->clock > 170000) {
271		dev_warn(ldb->dev,
272			 "%s: mode exceeds 170 MHz pixel clock\n", __func__);
273	}
274	if (mode->clock > 85000 && !dual) {
275		dev_warn(ldb->dev,
276			 "%s: mode exceeds 85 MHz pixel clock\n", __func__);
277	}
278
279	if (dual) {
280		serial_clk = 3500UL * mode->clock;
281		imx_ldb_set_clock(ldb, mux, 0, serial_clk, di_clk);
282		imx_ldb_set_clock(ldb, mux, 1, serial_clk, di_clk);
283	} else {
284		serial_clk = 7000UL * mode->clock;
285		imx_ldb_set_clock(ldb, mux, imx_ldb_ch->chno, serial_clk,
286				  di_clk);
287	}
288
289	/* FIXME - assumes straight connections DI0 --> CH0, DI1 --> CH1 */
290	if (imx_ldb_ch == &ldb->channel[0]) {
291		if (mode->flags & DRM_MODE_FLAG_NVSYNC)
292			ldb->ldb_ctrl |= LDB_DI0_VS_POL_ACT_LOW;
293		else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
294			ldb->ldb_ctrl &= ~LDB_DI0_VS_POL_ACT_LOW;
295	}
296	if (imx_ldb_ch == &ldb->channel[1]) {
297		if (mode->flags & DRM_MODE_FLAG_NVSYNC)
298			ldb->ldb_ctrl |= LDB_DI1_VS_POL_ACT_LOW;
299		else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
300			ldb->ldb_ctrl &= ~LDB_DI1_VS_POL_ACT_LOW;
301	}
302}
303
304static void imx_ldb_encoder_disable(struct drm_encoder *encoder)
305{
306	struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
307	struct imx_ldb *ldb = imx_ldb_ch->ldb;
308	int mux, ret;
309
310	/*
311	 * imx_ldb_encoder_disable is called by
312	 * drm_helper_disable_unused_functions without
313	 * the encoder being enabled before.
314	 */
315	if (imx_ldb_ch == &ldb->channel[0] &&
316	    (ldb->ldb_ctrl & LDB_CH0_MODE_EN_MASK) == 0)
317		return;
318	else if (imx_ldb_ch == &ldb->channel[1] &&
319		 (ldb->ldb_ctrl & LDB_CH1_MODE_EN_MASK) == 0)
320		return;
321
322	drm_panel_disable(imx_ldb_ch->panel);
323
324	if (imx_ldb_ch == &ldb->channel[0])
325		ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
326	else if (imx_ldb_ch == &ldb->channel[1])
327		ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
328
329	regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
330
331	if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
332		clk_disable_unprepare(ldb->clk[0]);
333		clk_disable_unprepare(ldb->clk[1]);
334	}
335
336	if (ldb->lvds_mux) {
337		const struct bus_mux *lvds_mux = NULL;
338
339		if (imx_ldb_ch == &ldb->channel[0])
340			lvds_mux = &ldb->lvds_mux[0];
341		else if (imx_ldb_ch == &ldb->channel[1])
342			lvds_mux = &ldb->lvds_mux[1];
343
344		regmap_read(ldb->regmap, lvds_mux->reg, &mux);
345		mux &= lvds_mux->mask;
346		mux >>= lvds_mux->shift;
347	} else {
348		mux = (imx_ldb_ch == &ldb->channel[0]) ? 0 : 1;
349	}
350
351	/* set display clock mux back to original input clock */
352	ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk_parent[mux]);
353	if (ret)
354		dev_err(ldb->dev,
355			"unable to set di%d parent clock to original parent\n",
356			mux);
357
358	drm_panel_unprepare(imx_ldb_ch->panel);
359}
360
361static struct drm_connector_funcs imx_ldb_connector_funcs = {
362	.dpms = drm_helper_connector_dpms,
363	.fill_modes = drm_helper_probe_single_connector_modes,
364	.detect = imx_ldb_connector_detect,
365	.destroy = imx_drm_connector_destroy,
366};
367
368static struct drm_connector_helper_funcs imx_ldb_connector_helper_funcs = {
369	.get_modes = imx_ldb_connector_get_modes,
370	.best_encoder = imx_ldb_connector_best_encoder,
371};
372
373static struct drm_encoder_funcs imx_ldb_encoder_funcs = {
374	.destroy = imx_drm_encoder_destroy,
375};
376
377static struct drm_encoder_helper_funcs imx_ldb_encoder_helper_funcs = {
378	.dpms = imx_ldb_encoder_dpms,
379	.mode_fixup = imx_ldb_encoder_mode_fixup,
380	.prepare = imx_ldb_encoder_prepare,
381	.commit = imx_ldb_encoder_commit,
382	.mode_set = imx_ldb_encoder_mode_set,
383	.disable = imx_ldb_encoder_disable,
384};
385
386static int imx_ldb_get_clk(struct imx_ldb *ldb, int chno)
387{
388	char clkname[16];
389
390	snprintf(clkname, sizeof(clkname), "di%d", chno);
391	ldb->clk[chno] = devm_clk_get(ldb->dev, clkname);
392	if (IS_ERR(ldb->clk[chno]))
393		return PTR_ERR(ldb->clk[chno]);
394
395	snprintf(clkname, sizeof(clkname), "di%d_pll", chno);
396	ldb->clk_pll[chno] = devm_clk_get(ldb->dev, clkname);
397
398	return PTR_ERR_OR_ZERO(ldb->clk_pll[chno]);
399}
400
401static int imx_ldb_register(struct drm_device *drm,
402	struct imx_ldb_channel *imx_ldb_ch)
403{
404	struct imx_ldb *ldb = imx_ldb_ch->ldb;
405	int ret;
406
407	ret = imx_drm_encoder_parse_of(drm, &imx_ldb_ch->encoder,
408				       imx_ldb_ch->child);
409	if (ret)
410		return ret;
411
412	ret = imx_ldb_get_clk(ldb, imx_ldb_ch->chno);
413	if (ret)
414		return ret;
415
416	if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
417		ret = imx_ldb_get_clk(ldb, 1);
418		if (ret)
419			return ret;
420	}
421
422	drm_encoder_helper_add(&imx_ldb_ch->encoder,
423			&imx_ldb_encoder_helper_funcs);
424	drm_encoder_init(drm, &imx_ldb_ch->encoder, &imx_ldb_encoder_funcs,
425			 DRM_MODE_ENCODER_LVDS);
426
427	drm_connector_helper_add(&imx_ldb_ch->connector,
428			&imx_ldb_connector_helper_funcs);
429	drm_connector_init(drm, &imx_ldb_ch->connector,
430			   &imx_ldb_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
431
432	if (imx_ldb_ch->panel)
433		drm_panel_attach(imx_ldb_ch->panel, &imx_ldb_ch->connector);
434
435	drm_mode_connector_attach_encoder(&imx_ldb_ch->connector,
436			&imx_ldb_ch->encoder);
437
438	return 0;
439}
440
441enum {
442	LVDS_BIT_MAP_SPWG,
443	LVDS_BIT_MAP_JEIDA
444};
445
446struct imx_ldb_bit_mapping {
447	u32 bus_format;
448	u32 datawidth;
449	const char * const mapping;
450};
451
452static const struct imx_ldb_bit_mapping imx_ldb_bit_mappings[] = {
453	{ MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,  18, "spwg" },
454	{ MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,  24, "spwg" },
455	{ MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, 24, "jeida" },
456};
457
458static u32 of_get_bus_format(struct device *dev, struct device_node *np)
459{
460	const char *bm;
461	u32 datawidth = 0;
462	int ret, i;
463
464	ret = of_property_read_string(np, "fsl,data-mapping", &bm);
465	if (ret < 0)
466		return ret;
467
468	of_property_read_u32(np, "fsl,data-width", &datawidth);
469
470	for (i = 0; i < ARRAY_SIZE(imx_ldb_bit_mappings); i++) {
471		if (!strcasecmp(bm, imx_ldb_bit_mappings[i].mapping) &&
472		    datawidth == imx_ldb_bit_mappings[i].datawidth)
473			return imx_ldb_bit_mappings[i].bus_format;
474	}
475
476	dev_err(dev, "invalid data mapping: %d-bit \"%s\"\n", datawidth, bm);
477
478	return -ENOENT;
479}
480
481static struct bus_mux imx6q_lvds_mux[2] = {
482	{
483		.reg = IOMUXC_GPR3,
484		.shift = 6,
485		.mask = IMX6Q_GPR3_LVDS0_MUX_CTL_MASK,
486	}, {
487		.reg = IOMUXC_GPR3,
488		.shift = 8,
489		.mask = IMX6Q_GPR3_LVDS1_MUX_CTL_MASK,
490	}
491};
492
493/*
494 * For a device declaring compatible = "fsl,imx6q-ldb", "fsl,imx53-ldb",
495 * of_match_device will walk through this list and take the first entry
496 * matching any of its compatible values. Therefore, the more generic
497 * entries (in this case fsl,imx53-ldb) need to be ordered last.
498 */
499static const struct of_device_id imx_ldb_dt_ids[] = {
500	{ .compatible = "fsl,imx6q-ldb", .data = imx6q_lvds_mux, },
501	{ .compatible = "fsl,imx53-ldb", .data = NULL, },
502	{ }
503};
504MODULE_DEVICE_TABLE(of, imx_ldb_dt_ids);
505
506static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
507{
508	struct drm_device *drm = data;
509	struct device_node *np = dev->of_node;
510	const struct of_device_id *of_id =
511			of_match_device(imx_ldb_dt_ids, dev);
512	struct device_node *child;
513	const u8 *edidp;
514	struct imx_ldb *imx_ldb;
515	int dual;
516	int ret;
517	int i;
518
519	imx_ldb = devm_kzalloc(dev, sizeof(*imx_ldb), GFP_KERNEL);
520	if (!imx_ldb)
521		return -ENOMEM;
522
523	imx_ldb->regmap = syscon_regmap_lookup_by_phandle(np, "gpr");
524	if (IS_ERR(imx_ldb->regmap)) {
525		dev_err(dev, "failed to get parent regmap\n");
526		return PTR_ERR(imx_ldb->regmap);
527	}
528
529	imx_ldb->dev = dev;
530
531	if (of_id)
532		imx_ldb->lvds_mux = of_id->data;
533
534	dual = of_property_read_bool(np, "fsl,dual-channel");
535	if (dual)
536		imx_ldb->ldb_ctrl |= LDB_SPLIT_MODE_EN;
537
538	/*
539	 * There are three different possible clock mux configurations:
540	 * i.MX53:  ipu1_di0_sel, ipu1_di1_sel
541	 * i.MX6q:  ipu1_di0_sel, ipu1_di1_sel, ipu2_di0_sel, ipu2_di1_sel
542	 * i.MX6dl: ipu1_di0_sel, ipu1_di1_sel, lcdif_sel
543	 * Map them all to di0_sel...di3_sel.
544	 */
545	for (i = 0; i < 4; i++) {
546		char clkname[16];
547
548		sprintf(clkname, "di%d_sel", i);
549		imx_ldb->clk_sel[i] = devm_clk_get(imx_ldb->dev, clkname);
550		if (IS_ERR(imx_ldb->clk_sel[i])) {
551			ret = PTR_ERR(imx_ldb->clk_sel[i]);
552			imx_ldb->clk_sel[i] = NULL;
553			break;
554		}
555
556		imx_ldb->clk_parent[i] = clk_get_parent(imx_ldb->clk_sel[i]);
557	}
558	if (i == 0)
559		return ret;
560
561	for_each_child_of_node(np, child) {
562		struct imx_ldb_channel *channel;
563		struct device_node *port;
564
565		ret = of_property_read_u32(child, "reg", &i);
566		if (ret || i < 0 || i > 1)
567			return -EINVAL;
568
569		if (dual && i > 0) {
570			dev_warn(dev, "dual-channel mode, ignoring second output\n");
571			continue;
572		}
573
574		if (!of_device_is_available(child))
575			continue;
576
577		channel = &imx_ldb->channel[i];
578		channel->ldb = imx_ldb;
579		channel->chno = i;
580		channel->child = child;
581
582		/*
583		 * The output port is port@4 with an external 4-port mux or
584		 * port@2 with the internal 2-port mux.
585		 */
586		port = of_graph_get_port_by_id(child, imx_ldb->lvds_mux ? 4 : 2);
587		if (port) {
588			struct device_node *endpoint, *remote;
589
590			endpoint = of_get_child_by_name(port, "endpoint");
591			if (endpoint) {
592				remote = of_graph_get_remote_port_parent(endpoint);
593				if (remote)
594					channel->panel = of_drm_find_panel(remote);
595				else
596					return -EPROBE_DEFER;
597				if (!channel->panel) {
598					dev_err(dev, "panel not found: %s\n",
599						remote->full_name);
600					return -EPROBE_DEFER;
601				}
602			}
603		}
604
605		edidp = of_get_property(child, "edid", &channel->edid_len);
606		if (edidp) {
607			channel->edid = kmemdup(edidp, channel->edid_len,
608						GFP_KERNEL);
609		} else if (!channel->panel) {
610			ret = of_get_drm_display_mode(child, &channel->mode, 0);
611			if (!ret)
612				channel->mode_valid = 1;
613		}
614
615		channel->bus_format = of_get_bus_format(dev, child);
616		if (channel->bus_format == -EINVAL) {
617			/*
618			 * If no bus format was specified in the device tree,
619			 * we can still get it from the connected panel later.
620			 */
621			if (channel->panel && channel->panel->funcs &&
622			    channel->panel->funcs->get_modes)
623				channel->bus_format = 0;
624		}
625		if (channel->bus_format < 0) {
626			dev_err(dev, "could not determine data mapping: %d\n",
627				channel->bus_format);
628			return channel->bus_format;
629		}
630
631		ret = imx_ldb_register(drm, channel);
632		if (ret)
633			return ret;
634	}
635
636	dev_set_drvdata(dev, imx_ldb);
637
638	return 0;
639}
640
641static void imx_ldb_unbind(struct device *dev, struct device *master,
642	void *data)
643{
644	struct imx_ldb *imx_ldb = dev_get_drvdata(dev);
645	int i;
646
647	for (i = 0; i < 2; i++) {
648		struct imx_ldb_channel *channel = &imx_ldb->channel[i];
649
650		if (!channel->connector.funcs)
651			continue;
652
653		channel->connector.funcs->destroy(&channel->connector);
654		channel->encoder.funcs->destroy(&channel->encoder);
655
656		kfree(channel->edid);
657	}
658}
659
660static const struct component_ops imx_ldb_ops = {
661	.bind	= imx_ldb_bind,
662	.unbind	= imx_ldb_unbind,
663};
664
665static int imx_ldb_probe(struct platform_device *pdev)
666{
667	return component_add(&pdev->dev, &imx_ldb_ops);
668}
669
670static int imx_ldb_remove(struct platform_device *pdev)
671{
672	component_del(&pdev->dev, &imx_ldb_ops);
673	return 0;
674}
675
676static struct platform_driver imx_ldb_driver = {
677	.probe		= imx_ldb_probe,
678	.remove		= imx_ldb_remove,
679	.driver		= {
680		.of_match_table = imx_ldb_dt_ids,
681		.name	= DRIVER_NAME,
682	},
683};
684
685module_platform_driver(imx_ldb_driver);
686
687MODULE_DESCRIPTION("i.MX LVDS driver");
688MODULE_AUTHOR("Sascha Hauer, Pengutronix");
689MODULE_LICENSE("GPL");
690MODULE_ALIAS("platform:" DRIVER_NAME);
691