Linux-libre 4.14.44-gnu
[librecmc/linux-libre.git] / drivers / gpu / drm / imx / imx-ldb.c
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_atomic.h>
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_fb_helper.h>
23 #include <drm/drm_crtc_helper.h>
24 #include <drm/drm_of.h>
25 #include <drm/drm_panel.h>
26 #include <linux/mfd/syscon.h>
27 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
28 #include <linux/of_device.h>
29 #include <linux/of_graph.h>
30 #include <video/of_display_timing.h>
31 #include <video/of_videomode.h>
32 #include <linux/regmap.h>
33 #include <linux/videodev2.h>
34
35 #include "imx-drm.h"
36
37 #define DRIVER_NAME "imx-ldb"
38
39 #define LDB_CH0_MODE_EN_TO_DI0          (1 << 0)
40 #define LDB_CH0_MODE_EN_TO_DI1          (3 << 0)
41 #define LDB_CH0_MODE_EN_MASK            (3 << 0)
42 #define LDB_CH1_MODE_EN_TO_DI0          (1 << 2)
43 #define LDB_CH1_MODE_EN_TO_DI1          (3 << 2)
44 #define LDB_CH1_MODE_EN_MASK            (3 << 2)
45 #define LDB_SPLIT_MODE_EN               (1 << 4)
46 #define LDB_DATA_WIDTH_CH0_24           (1 << 5)
47 #define LDB_BIT_MAP_CH0_JEIDA           (1 << 6)
48 #define LDB_DATA_WIDTH_CH1_24           (1 << 7)
49 #define LDB_BIT_MAP_CH1_JEIDA           (1 << 8)
50 #define LDB_DI0_VS_POL_ACT_LOW          (1 << 9)
51 #define LDB_DI1_VS_POL_ACT_LOW          (1 << 10)
52 #define LDB_BGREF_RMODE_INT             (1 << 15)
53
54 struct imx_ldb;
55
56 struct imx_ldb_channel {
57         struct imx_ldb *ldb;
58         struct drm_connector connector;
59         struct drm_encoder encoder;
60
61         /* Defines what is connected to the ldb, only one at a time */
62         struct drm_panel *panel;
63         struct drm_bridge *bridge;
64
65         struct device_node *child;
66         struct i2c_adapter *ddc;
67         int chno;
68         void *edid;
69         int edid_len;
70         struct drm_display_mode mode;
71         int mode_valid;
72         u32 bus_format;
73         u32 bus_flags;
74 };
75
76 static inline struct imx_ldb_channel *con_to_imx_ldb_ch(struct drm_connector *c)
77 {
78         return container_of(c, struct imx_ldb_channel, connector);
79 }
80
81 static inline struct imx_ldb_channel *enc_to_imx_ldb_ch(struct drm_encoder *e)
82 {
83         return container_of(e, struct imx_ldb_channel, encoder);
84 }
85
86 struct bus_mux {
87         int reg;
88         int shift;
89         int mask;
90 };
91
92 struct imx_ldb {
93         struct regmap *regmap;
94         struct device *dev;
95         struct imx_ldb_channel channel[2];
96         struct clk *clk[2]; /* our own clock */
97         struct clk *clk_sel[4]; /* parent of display clock */
98         struct clk *clk_parent[4]; /* original parent of clk_sel */
99         struct clk *clk_pll[2]; /* upstream clock we can adjust */
100         u32 ldb_ctrl;
101         const struct bus_mux *lvds_mux;
102 };
103
104 static void imx_ldb_ch_set_bus_format(struct imx_ldb_channel *imx_ldb_ch,
105                                       u32 bus_format)
106 {
107         struct imx_ldb *ldb = imx_ldb_ch->ldb;
108         int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
109
110         switch (bus_format) {
111         case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
112                 break;
113         case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
114                 if (imx_ldb_ch->chno == 0 || dual)
115                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24;
116                 if (imx_ldb_ch->chno == 1 || dual)
117                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24;
118                 break;
119         case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
120                 if (imx_ldb_ch->chno == 0 || dual)
121                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24 |
122                                          LDB_BIT_MAP_CH0_JEIDA;
123                 if (imx_ldb_ch->chno == 1 || dual)
124                         ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24 |
125                                          LDB_BIT_MAP_CH1_JEIDA;
126                 break;
127         }
128 }
129
130 static int imx_ldb_connector_get_modes(struct drm_connector *connector)
131 {
132         struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
133         int num_modes = 0;
134
135         if (imx_ldb_ch->panel && imx_ldb_ch->panel->funcs &&
136             imx_ldb_ch->panel->funcs->get_modes) {
137                 num_modes = imx_ldb_ch->panel->funcs->get_modes(imx_ldb_ch->panel);
138                 if (num_modes > 0)
139                         return num_modes;
140         }
141
142         if (!imx_ldb_ch->edid && imx_ldb_ch->ddc)
143                 imx_ldb_ch->edid = drm_get_edid(connector, imx_ldb_ch->ddc);
144
145         if (imx_ldb_ch->edid) {
146                 drm_mode_connector_update_edid_property(connector,
147                                                         imx_ldb_ch->edid);
148                 num_modes = drm_add_edid_modes(connector, imx_ldb_ch->edid);
149         }
150
151         if (imx_ldb_ch->mode_valid) {
152                 struct drm_display_mode *mode;
153
154                 mode = drm_mode_create(connector->dev);
155                 if (!mode)
156                         return -EINVAL;
157                 drm_mode_copy(mode, &imx_ldb_ch->mode);
158                 mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
159                 drm_mode_probed_add(connector, mode);
160                 num_modes++;
161         }
162
163         return num_modes;
164 }
165
166 static struct drm_encoder *imx_ldb_connector_best_encoder(
167                 struct drm_connector *connector)
168 {
169         struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
170
171         return &imx_ldb_ch->encoder;
172 }
173
174 static void imx_ldb_set_clock(struct imx_ldb *ldb, int mux, int chno,
175                 unsigned long serial_clk, unsigned long di_clk)
176 {
177         int ret;
178
179         dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
180                         clk_get_rate(ldb->clk_pll[chno]), serial_clk);
181         clk_set_rate(ldb->clk_pll[chno], serial_clk);
182
183         dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
184                         clk_get_rate(ldb->clk_pll[chno]));
185
186         dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
187                         clk_get_rate(ldb->clk[chno]),
188                         (long int)di_clk);
189         clk_set_rate(ldb->clk[chno], di_clk);
190
191         dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
192                         clk_get_rate(ldb->clk[chno]));
193
194         /* set display clock mux to LDB input clock */
195         ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk[chno]);
196         if (ret)
197                 dev_err(ldb->dev,
198                         "unable to set di%d parent clock to ldb_di%d\n", mux,
199                         chno);
200 }
201
202 static void imx_ldb_encoder_enable(struct drm_encoder *encoder)
203 {
204         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
205         struct imx_ldb *ldb = imx_ldb_ch->ldb;
206         int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
207         int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder);
208
209         drm_panel_prepare(imx_ldb_ch->panel);
210
211         if (dual) {
212                 clk_set_parent(ldb->clk_sel[mux], ldb->clk[0]);
213                 clk_set_parent(ldb->clk_sel[mux], ldb->clk[1]);
214
215                 clk_prepare_enable(ldb->clk[0]);
216                 clk_prepare_enable(ldb->clk[1]);
217         } else {
218                 clk_set_parent(ldb->clk_sel[mux], ldb->clk[imx_ldb_ch->chno]);
219         }
220
221         if (imx_ldb_ch == &ldb->channel[0] || dual) {
222                 ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
223                 if (mux == 0 || ldb->lvds_mux)
224                         ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI0;
225                 else if (mux == 1)
226                         ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI1;
227         }
228         if (imx_ldb_ch == &ldb->channel[1] || dual) {
229                 ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
230                 if (mux == 1 || ldb->lvds_mux)
231                         ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI1;
232                 else if (mux == 0)
233                         ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI0;
234         }
235
236         if (ldb->lvds_mux) {
237                 const struct bus_mux *lvds_mux = NULL;
238
239                 if (imx_ldb_ch == &ldb->channel[0])
240                         lvds_mux = &ldb->lvds_mux[0];
241                 else if (imx_ldb_ch == &ldb->channel[1])
242                         lvds_mux = &ldb->lvds_mux[1];
243
244                 regmap_update_bits(ldb->regmap, lvds_mux->reg, lvds_mux->mask,
245                                    mux << lvds_mux->shift);
246         }
247
248         regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
249
250         drm_panel_enable(imx_ldb_ch->panel);
251 }
252
253 static void
254 imx_ldb_encoder_atomic_mode_set(struct drm_encoder *encoder,
255                                 struct drm_crtc_state *crtc_state,
256                                 struct drm_connector_state *connector_state)
257 {
258         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
259         struct drm_display_mode *mode = &crtc_state->adjusted_mode;
260         struct imx_ldb *ldb = imx_ldb_ch->ldb;
261         int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
262         unsigned long serial_clk;
263         unsigned long di_clk = mode->clock * 1000;
264         int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder);
265         u32 bus_format = imx_ldb_ch->bus_format;
266
267         if (mode->clock > 170000) {
268                 dev_warn(ldb->dev,
269                          "%s: mode exceeds 170 MHz pixel clock\n", __func__);
270         }
271         if (mode->clock > 85000 && !dual) {
272                 dev_warn(ldb->dev,
273                          "%s: mode exceeds 85 MHz pixel clock\n", __func__);
274         }
275
276         if (dual) {
277                 serial_clk = 3500UL * mode->clock;
278                 imx_ldb_set_clock(ldb, mux, 0, serial_clk, di_clk);
279                 imx_ldb_set_clock(ldb, mux, 1, serial_clk, di_clk);
280         } else {
281                 serial_clk = 7000UL * mode->clock;
282                 imx_ldb_set_clock(ldb, mux, imx_ldb_ch->chno, serial_clk,
283                                   di_clk);
284         }
285
286         /* FIXME - assumes straight connections DI0 --> CH0, DI1 --> CH1 */
287         if (imx_ldb_ch == &ldb->channel[0] || dual) {
288                 if (mode->flags & DRM_MODE_FLAG_NVSYNC)
289                         ldb->ldb_ctrl |= LDB_DI0_VS_POL_ACT_LOW;
290                 else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
291                         ldb->ldb_ctrl &= ~LDB_DI0_VS_POL_ACT_LOW;
292         }
293         if (imx_ldb_ch == &ldb->channel[1] || dual) {
294                 if (mode->flags & DRM_MODE_FLAG_NVSYNC)
295                         ldb->ldb_ctrl |= LDB_DI1_VS_POL_ACT_LOW;
296                 else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
297                         ldb->ldb_ctrl &= ~LDB_DI1_VS_POL_ACT_LOW;
298         }
299
300         if (!bus_format) {
301                 struct drm_connector *connector = connector_state->connector;
302                 struct drm_display_info *di = &connector->display_info;
303
304                 if (di->num_bus_formats)
305                         bus_format = di->bus_formats[0];
306         }
307         imx_ldb_ch_set_bus_format(imx_ldb_ch, bus_format);
308 }
309
310 static void imx_ldb_encoder_disable(struct drm_encoder *encoder)
311 {
312         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
313         struct imx_ldb *ldb = imx_ldb_ch->ldb;
314         int mux, ret;
315
316         drm_panel_disable(imx_ldb_ch->panel);
317
318         if (imx_ldb_ch == &ldb->channel[0])
319                 ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
320         else if (imx_ldb_ch == &ldb->channel[1])
321                 ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
322
323         regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
324
325         if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
326                 clk_disable_unprepare(ldb->clk[0]);
327                 clk_disable_unprepare(ldb->clk[1]);
328         }
329
330         if (ldb->lvds_mux) {
331                 const struct bus_mux *lvds_mux = NULL;
332
333                 if (imx_ldb_ch == &ldb->channel[0])
334                         lvds_mux = &ldb->lvds_mux[0];
335                 else if (imx_ldb_ch == &ldb->channel[1])
336                         lvds_mux = &ldb->lvds_mux[1];
337
338                 regmap_read(ldb->regmap, lvds_mux->reg, &mux);
339                 mux &= lvds_mux->mask;
340                 mux >>= lvds_mux->shift;
341         } else {
342                 mux = (imx_ldb_ch == &ldb->channel[0]) ? 0 : 1;
343         }
344
345         /* set display clock mux back to original input clock */
346         ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk_parent[mux]);
347         if (ret)
348                 dev_err(ldb->dev,
349                         "unable to set di%d parent clock to original parent\n",
350                         mux);
351
352         drm_panel_unprepare(imx_ldb_ch->panel);
353 }
354
355 static int imx_ldb_encoder_atomic_check(struct drm_encoder *encoder,
356                                         struct drm_crtc_state *crtc_state,
357                                         struct drm_connector_state *conn_state)
358 {
359         struct imx_crtc_state *imx_crtc_state = to_imx_crtc_state(crtc_state);
360         struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
361         struct drm_display_info *di = &conn_state->connector->display_info;
362         u32 bus_format = imx_ldb_ch->bus_format;
363
364         /* Bus format description in DT overrides connector display info. */
365         if (!bus_format && di->num_bus_formats) {
366                 bus_format = di->bus_formats[0];
367                 imx_crtc_state->bus_flags = di->bus_flags;
368         } else {
369                 bus_format = imx_ldb_ch->bus_format;
370                 imx_crtc_state->bus_flags = imx_ldb_ch->bus_flags;
371         }
372         switch (bus_format) {
373         case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
374                 imx_crtc_state->bus_format = MEDIA_BUS_FMT_RGB666_1X18;
375                 break;
376         case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
377         case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
378                 imx_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
379                 break;
380         default:
381                 return -EINVAL;
382         }
383
384         imx_crtc_state->di_hsync_pin = 2;
385         imx_crtc_state->di_vsync_pin = 3;
386
387         return 0;
388 }
389
390
391 static const struct drm_connector_funcs imx_ldb_connector_funcs = {
392         .fill_modes = drm_helper_probe_single_connector_modes,
393         .destroy = imx_drm_connector_destroy,
394         .reset = drm_atomic_helper_connector_reset,
395         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
396         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
397 };
398
399 static const struct drm_connector_helper_funcs imx_ldb_connector_helper_funcs = {
400         .get_modes = imx_ldb_connector_get_modes,
401         .best_encoder = imx_ldb_connector_best_encoder,
402 };
403
404 static const struct drm_encoder_funcs imx_ldb_encoder_funcs = {
405         .destroy = imx_drm_encoder_destroy,
406 };
407
408 static const struct drm_encoder_helper_funcs imx_ldb_encoder_helper_funcs = {
409         .atomic_mode_set = imx_ldb_encoder_atomic_mode_set,
410         .enable = imx_ldb_encoder_enable,
411         .disable = imx_ldb_encoder_disable,
412         .atomic_check = imx_ldb_encoder_atomic_check,
413 };
414
415 static int imx_ldb_get_clk(struct imx_ldb *ldb, int chno)
416 {
417         char clkname[16];
418
419         snprintf(clkname, sizeof(clkname), "di%d", chno);
420         ldb->clk[chno] = devm_clk_get(ldb->dev, clkname);
421         if (IS_ERR(ldb->clk[chno]))
422                 return PTR_ERR(ldb->clk[chno]);
423
424         snprintf(clkname, sizeof(clkname), "di%d_pll", chno);
425         ldb->clk_pll[chno] = devm_clk_get(ldb->dev, clkname);
426
427         return PTR_ERR_OR_ZERO(ldb->clk_pll[chno]);
428 }
429
430 static int imx_ldb_register(struct drm_device *drm,
431         struct imx_ldb_channel *imx_ldb_ch)
432 {
433         struct imx_ldb *ldb = imx_ldb_ch->ldb;
434         struct drm_encoder *encoder = &imx_ldb_ch->encoder;
435         int ret;
436
437         ret = imx_drm_encoder_parse_of(drm, encoder, imx_ldb_ch->child);
438         if (ret)
439                 return ret;
440
441         ret = imx_ldb_get_clk(ldb, imx_ldb_ch->chno);
442         if (ret)
443                 return ret;
444
445         if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
446                 ret = imx_ldb_get_clk(ldb, 1);
447                 if (ret)
448                         return ret;
449         }
450
451         drm_encoder_helper_add(encoder, &imx_ldb_encoder_helper_funcs);
452         drm_encoder_init(drm, encoder, &imx_ldb_encoder_funcs,
453                          DRM_MODE_ENCODER_LVDS, NULL);
454
455         if (imx_ldb_ch->bridge) {
456                 ret = drm_bridge_attach(&imx_ldb_ch->encoder,
457                                         imx_ldb_ch->bridge, NULL);
458                 if (ret) {
459                         DRM_ERROR("Failed to initialize bridge with drm\n");
460                         return ret;
461                 }
462         } else {
463                 /*
464                  * We want to add the connector whenever there is no bridge
465                  * that brings its own, not only when there is a panel. For
466                  * historical reasons, the ldb driver can also work without
467                  * a panel.
468                  */
469                 drm_connector_helper_add(&imx_ldb_ch->connector,
470                                 &imx_ldb_connector_helper_funcs);
471                 drm_connector_init(drm, &imx_ldb_ch->connector,
472                                 &imx_ldb_connector_funcs,
473                                 DRM_MODE_CONNECTOR_LVDS);
474                 drm_mode_connector_attach_encoder(&imx_ldb_ch->connector,
475                                 encoder);
476         }
477
478         if (imx_ldb_ch->panel) {
479                 ret = drm_panel_attach(imx_ldb_ch->panel,
480                                        &imx_ldb_ch->connector);
481                 if (ret)
482                         return ret;
483         }
484
485         return 0;
486 }
487
488 enum {
489         LVDS_BIT_MAP_SPWG,
490         LVDS_BIT_MAP_JEIDA
491 };
492
493 struct imx_ldb_bit_mapping {
494         u32 bus_format;
495         u32 datawidth;
496         const char * const mapping;
497 };
498
499 static const struct imx_ldb_bit_mapping imx_ldb_bit_mappings[] = {
500         { MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,  18, "spwg" },
501         { MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,  24, "spwg" },
502         { MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, 24, "jeida" },
503 };
504
505 static u32 of_get_bus_format(struct device *dev, struct device_node *np)
506 {
507         const char *bm;
508         u32 datawidth = 0;
509         int ret, i;
510
511         ret = of_property_read_string(np, "fsl,data-mapping", &bm);
512         if (ret < 0)
513                 return ret;
514
515         of_property_read_u32(np, "fsl,data-width", &datawidth);
516
517         for (i = 0; i < ARRAY_SIZE(imx_ldb_bit_mappings); i++) {
518                 if (!strcasecmp(bm, imx_ldb_bit_mappings[i].mapping) &&
519                     datawidth == imx_ldb_bit_mappings[i].datawidth)
520                         return imx_ldb_bit_mappings[i].bus_format;
521         }
522
523         dev_err(dev, "invalid data mapping: %d-bit \"%s\"\n", datawidth, bm);
524
525         return -ENOENT;
526 }
527
528 static struct bus_mux imx6q_lvds_mux[2] = {
529         {
530                 .reg = IOMUXC_GPR3,
531                 .shift = 6,
532                 .mask = IMX6Q_GPR3_LVDS0_MUX_CTL_MASK,
533         }, {
534                 .reg = IOMUXC_GPR3,
535                 .shift = 8,
536                 .mask = IMX6Q_GPR3_LVDS1_MUX_CTL_MASK,
537         }
538 };
539
540 /*
541  * For a device declaring compatible = "fsl,imx6q-ldb", "fsl,imx53-ldb",
542  * of_match_device will walk through this list and take the first entry
543  * matching any of its compatible values. Therefore, the more generic
544  * entries (in this case fsl,imx53-ldb) need to be ordered last.
545  */
546 static const struct of_device_id imx_ldb_dt_ids[] = {
547         { .compatible = "fsl,imx6q-ldb", .data = imx6q_lvds_mux, },
548         { .compatible = "fsl,imx53-ldb", .data = NULL, },
549         { }
550 };
551 MODULE_DEVICE_TABLE(of, imx_ldb_dt_ids);
552
553 static int imx_ldb_panel_ddc(struct device *dev,
554                 struct imx_ldb_channel *channel, struct device_node *child)
555 {
556         struct device_node *ddc_node;
557         const u8 *edidp;
558         int ret;
559
560         ddc_node = of_parse_phandle(child, "ddc-i2c-bus", 0);
561         if (ddc_node) {
562                 channel->ddc = of_find_i2c_adapter_by_node(ddc_node);
563                 of_node_put(ddc_node);
564                 if (!channel->ddc) {
565                         dev_warn(dev, "failed to get ddc i2c adapter\n");
566                         return -EPROBE_DEFER;
567                 }
568         }
569
570         if (!channel->ddc) {
571                 /* if no DDC available, fallback to hardcoded EDID */
572                 dev_dbg(dev, "no ddc available\n");
573
574                 edidp = of_get_property(child, "edid",
575                                         &channel->edid_len);
576                 if (edidp) {
577                         channel->edid = kmemdup(edidp,
578                                                 channel->edid_len,
579                                                 GFP_KERNEL);
580                 } else if (!channel->panel) {
581                         /* fallback to display-timings node */
582                         ret = of_get_drm_display_mode(child,
583                                                       &channel->mode,
584                                                       &channel->bus_flags,
585                                                       OF_USE_NATIVE_MODE);
586                         if (!ret)
587                                 channel->mode_valid = 1;
588                 }
589         }
590         return 0;
591 }
592
593 static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
594 {
595         struct drm_device *drm = data;
596         struct device_node *np = dev->of_node;
597         const struct of_device_id *of_id =
598                         of_match_device(imx_ldb_dt_ids, dev);
599         struct device_node *child;
600         struct imx_ldb *imx_ldb;
601         int dual;
602         int ret;
603         int i;
604
605         imx_ldb = devm_kzalloc(dev, sizeof(*imx_ldb), GFP_KERNEL);
606         if (!imx_ldb)
607                 return -ENOMEM;
608
609         imx_ldb->regmap = syscon_regmap_lookup_by_phandle(np, "gpr");
610         if (IS_ERR(imx_ldb->regmap)) {
611                 dev_err(dev, "failed to get parent regmap\n");
612                 return PTR_ERR(imx_ldb->regmap);
613         }
614
615         imx_ldb->dev = dev;
616
617         if (of_id)
618                 imx_ldb->lvds_mux = of_id->data;
619
620         dual = of_property_read_bool(np, "fsl,dual-channel");
621         if (dual)
622                 imx_ldb->ldb_ctrl |= LDB_SPLIT_MODE_EN;
623
624         /*
625          * There are three different possible clock mux configurations:
626          * i.MX53:  ipu1_di0_sel, ipu1_di1_sel
627          * i.MX6q:  ipu1_di0_sel, ipu1_di1_sel, ipu2_di0_sel, ipu2_di1_sel
628          * i.MX6dl: ipu1_di0_sel, ipu1_di1_sel, lcdif_sel
629          * Map them all to di0_sel...di3_sel.
630          */
631         for (i = 0; i < 4; i++) {
632                 char clkname[16];
633
634                 sprintf(clkname, "di%d_sel", i);
635                 imx_ldb->clk_sel[i] = devm_clk_get(imx_ldb->dev, clkname);
636                 if (IS_ERR(imx_ldb->clk_sel[i])) {
637                         ret = PTR_ERR(imx_ldb->clk_sel[i]);
638                         imx_ldb->clk_sel[i] = NULL;
639                         break;
640                 }
641
642                 imx_ldb->clk_parent[i] = clk_get_parent(imx_ldb->clk_sel[i]);
643         }
644         if (i == 0)
645                 return ret;
646
647         for_each_child_of_node(np, child) {
648                 struct imx_ldb_channel *channel;
649                 int bus_format;
650
651                 ret = of_property_read_u32(child, "reg", &i);
652                 if (ret || i < 0 || i > 1)
653                         return -EINVAL;
654
655                 if (dual && i > 0) {
656                         dev_warn(dev, "dual-channel mode, ignoring second output\n");
657                         continue;
658                 }
659
660                 if (!of_device_is_available(child))
661                         continue;
662
663                 channel = &imx_ldb->channel[i];
664                 channel->ldb = imx_ldb;
665                 channel->chno = i;
666                 channel->child = child;
667
668                 /*
669                  * The output port is port@4 with an external 4-port mux or
670                  * port@2 with the internal 2-port mux.
671                  */
672                 ret = drm_of_find_panel_or_bridge(child,
673                                                   imx_ldb->lvds_mux ? 4 : 2, 0,
674                                                   &channel->panel, &channel->bridge);
675                 if (ret && ret != -ENODEV)
676                         return ret;
677
678                 /* panel ddc only if there is no bridge */
679                 if (!channel->bridge) {
680                         ret = imx_ldb_panel_ddc(dev, channel, child);
681                         if (ret)
682                                 return ret;
683                 }
684
685                 bus_format = of_get_bus_format(dev, child);
686                 if (bus_format == -EINVAL) {
687                         /*
688                          * If no bus format was specified in the device tree,
689                          * we can still get it from the connected panel later.
690                          */
691                         if (channel->panel && channel->panel->funcs &&
692                             channel->panel->funcs->get_modes)
693                                 bus_format = 0;
694                 }
695                 if (bus_format < 0) {
696                         dev_err(dev, "could not determine data mapping: %d\n",
697                                 bus_format);
698                         return bus_format;
699                 }
700                 channel->bus_format = bus_format;
701
702                 ret = imx_ldb_register(drm, channel);
703                 if (ret)
704                         return ret;
705         }
706
707         dev_set_drvdata(dev, imx_ldb);
708
709         return 0;
710 }
711
712 static void imx_ldb_unbind(struct device *dev, struct device *master,
713         void *data)
714 {
715         struct imx_ldb *imx_ldb = dev_get_drvdata(dev);
716         int i;
717
718         for (i = 0; i < 2; i++) {
719                 struct imx_ldb_channel *channel = &imx_ldb->channel[i];
720
721                 if (channel->panel)
722                         drm_panel_detach(channel->panel);
723
724                 kfree(channel->edid);
725                 i2c_put_adapter(channel->ddc);
726         }
727 }
728
729 static const struct component_ops imx_ldb_ops = {
730         .bind   = imx_ldb_bind,
731         .unbind = imx_ldb_unbind,
732 };
733
734 static int imx_ldb_probe(struct platform_device *pdev)
735 {
736         return component_add(&pdev->dev, &imx_ldb_ops);
737 }
738
739 static int imx_ldb_remove(struct platform_device *pdev)
740 {
741         component_del(&pdev->dev, &imx_ldb_ops);
742         return 0;
743 }
744
745 static struct platform_driver imx_ldb_driver = {
746         .probe          = imx_ldb_probe,
747         .remove         = imx_ldb_remove,
748         .driver         = {
749                 .of_match_table = imx_ldb_dt_ids,
750                 .name   = DRIVER_NAME,
751         },
752 };
753
754 module_platform_driver(imx_ldb_driver);
755
756 MODULE_DESCRIPTION("i.MX LVDS driver");
757 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
758 MODULE_LICENSE("GPL");
759 MODULE_ALIAS("platform:" DRIVER_NAME);