1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * i.MX drm driver - LVDS display bridge
4 *
5 * Copyright (C) 2012 Sascha Hauer, Pengutronix
6 */
7
8 #include <linux/clk.h>
9 #include <linux/component.h>
10 #include <linux/i2c.h>
11 #include <linux/media-bus-format.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_graph.h>
17 #include <linux/platform_device.h>
18 #include <linux/property.h>
19 #include <linux/regmap.h>
20 #include <linux/videodev2.h>
21
22 #include <drm/drm_atomic.h>
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_bridge_connector.h>
26 #include <drm/drm_managed.h>
27 #include <drm/drm_of.h>
28 #include <drm/drm_print.h>
29 #include <drm/drm_probe_helper.h>
30 #include <drm/drm_simple_kms_helper.h>
31 #include <drm/bridge/imx.h>
32
33 #include "imx-drm.h"
34
35 #define DRIVER_NAME "imx-ldb"
36
37 #define LDB_CH0_MODE_EN_TO_DI0 (1 << 0)
38 #define LDB_CH0_MODE_EN_TO_DI1 (3 << 0)
39 #define LDB_CH0_MODE_EN_MASK (3 << 0)
40 #define LDB_CH1_MODE_EN_TO_DI0 (1 << 2)
41 #define LDB_CH1_MODE_EN_TO_DI1 (3 << 2)
42 #define LDB_CH1_MODE_EN_MASK (3 << 2)
43 #define LDB_SPLIT_MODE_EN (1 << 4)
44 #define LDB_DATA_WIDTH_CH0_24 (1 << 5)
45 #define LDB_BIT_MAP_CH0_JEIDA (1 << 6)
46 #define LDB_DATA_WIDTH_CH1_24 (1 << 7)
47 #define LDB_BIT_MAP_CH1_JEIDA (1 << 8)
48 #define LDB_DI0_VS_POL_ACT_LOW (1 << 9)
49 #define LDB_DI1_VS_POL_ACT_LOW (1 << 10)
50 #define LDB_BGREF_RMODE_INT (1 << 15)
51
52 struct imx_ldb_channel;
53
54 struct imx_ldb_encoder {
55 struct drm_encoder encoder;
56 struct imx_ldb_channel *channel;
57 };
58
59 struct imx_ldb;
60
61 struct imx_ldb_channel {
62 struct imx_ldb *ldb;
63
64 struct drm_bridge *bridge;
65
66 struct device_node *child;
67 int chno;
68 u32 bus_format;
69 };
70
enc_to_imx_ldb_ch(struct drm_encoder * e)71 static inline struct imx_ldb_channel *enc_to_imx_ldb_ch(struct drm_encoder *e)
72 {
73 return container_of(e, struct imx_ldb_encoder, encoder)->channel;
74 }
75
76 struct bus_mux {
77 int reg;
78 int shift;
79 int mask;
80 };
81
82 struct imx_ldb {
83 struct regmap *regmap;
84 struct device *dev;
85 struct imx_ldb_channel channel[2];
86 struct clk *clk[2]; /* our own clock */
87 struct clk *clk_sel[4]; /* parent of display clock */
88 struct clk *clk_parent[4]; /* original parent of clk_sel */
89 struct clk *clk_pll[2]; /* upstream clock we can adjust */
90 u32 ldb_ctrl;
91 const struct bus_mux *lvds_mux;
92 };
93
imx_ldb_ch_set_bus_format(struct imx_ldb_channel * imx_ldb_ch,u32 bus_format)94 static void imx_ldb_ch_set_bus_format(struct imx_ldb_channel *imx_ldb_ch,
95 u32 bus_format)
96 {
97 struct imx_ldb *ldb = imx_ldb_ch->ldb;
98 int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
99
100 switch (bus_format) {
101 case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
102 break;
103 case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
104 if (imx_ldb_ch->chno == 0 || dual)
105 ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24;
106 if (imx_ldb_ch->chno == 1 || dual)
107 ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24;
108 break;
109 case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
110 if (imx_ldb_ch->chno == 0 || dual)
111 ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24 |
112 LDB_BIT_MAP_CH0_JEIDA;
113 if (imx_ldb_ch->chno == 1 || dual)
114 ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24 |
115 LDB_BIT_MAP_CH1_JEIDA;
116 break;
117 }
118 }
119
imx_ldb_set_clock(struct imx_ldb * ldb,int mux,int chno,unsigned long serial_clk,unsigned long di_clk)120 static void imx_ldb_set_clock(struct imx_ldb *ldb, int mux, int chno,
121 unsigned long serial_clk, unsigned long di_clk)
122 {
123 int ret;
124
125 dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
126 clk_get_rate(ldb->clk_pll[chno]), serial_clk);
127 clk_set_rate(ldb->clk_pll[chno], serial_clk);
128
129 dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
130 clk_get_rate(ldb->clk_pll[chno]));
131
132 dev_dbg(ldb->dev, "%s: now: %ld want: %ld\n", __func__,
133 clk_get_rate(ldb->clk[chno]),
134 (long int)di_clk);
135 clk_set_rate(ldb->clk[chno], di_clk);
136
137 dev_dbg(ldb->dev, "%s after: %ld\n", __func__,
138 clk_get_rate(ldb->clk[chno]));
139
140 /* set display clock mux to LDB input clock */
141 ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk[chno]);
142 if (ret)
143 dev_err(ldb->dev,
144 "unable to set di%d parent clock to ldb_di%d\n", mux,
145 chno);
146 }
147
imx_ldb_encoder_enable(struct drm_encoder * encoder)148 static void imx_ldb_encoder_enable(struct drm_encoder *encoder)
149 {
150 struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
151 struct imx_ldb *ldb = imx_ldb_ch->ldb;
152 int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
153 int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder);
154
155 if (mux < 0 || mux >= ARRAY_SIZE(ldb->clk_sel)) {
156 dev_warn(ldb->dev, "%s: invalid mux %d\n", __func__, mux);
157 return;
158 }
159
160 if (dual) {
161 clk_set_parent(ldb->clk_sel[mux], ldb->clk[0]);
162 clk_set_parent(ldb->clk_sel[mux], ldb->clk[1]);
163
164 clk_prepare_enable(ldb->clk[0]);
165 clk_prepare_enable(ldb->clk[1]);
166 } else {
167 clk_set_parent(ldb->clk_sel[mux], ldb->clk[imx_ldb_ch->chno]);
168 }
169
170 if (imx_ldb_ch == &ldb->channel[0] || dual) {
171 ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
172 if (mux == 0 || ldb->lvds_mux)
173 ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI0;
174 else if (mux == 1)
175 ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI1;
176 }
177 if (imx_ldb_ch == &ldb->channel[1] || dual) {
178 ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
179 if (mux == 1 || ldb->lvds_mux)
180 ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI1;
181 else if (mux == 0)
182 ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI0;
183 }
184
185 if (ldb->lvds_mux) {
186 const struct bus_mux *lvds_mux = NULL;
187
188 if (imx_ldb_ch == &ldb->channel[0])
189 lvds_mux = &ldb->lvds_mux[0];
190 else if (imx_ldb_ch == &ldb->channel[1])
191 lvds_mux = &ldb->lvds_mux[1];
192
193 regmap_update_bits(ldb->regmap, lvds_mux->reg, lvds_mux->mask,
194 mux << lvds_mux->shift);
195 }
196
197 regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
198 }
199
200 static void
imx_ldb_encoder_atomic_mode_set(struct drm_encoder * encoder,struct drm_crtc_state * crtc_state,struct drm_connector_state * connector_state)201 imx_ldb_encoder_atomic_mode_set(struct drm_encoder *encoder,
202 struct drm_crtc_state *crtc_state,
203 struct drm_connector_state *connector_state)
204 {
205 struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
206 struct drm_display_mode *mode = &crtc_state->adjusted_mode;
207 struct imx_ldb *ldb = imx_ldb_ch->ldb;
208 int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
209 unsigned long serial_clk;
210 unsigned long di_clk = mode->clock * 1000;
211 int mux = drm_of_encoder_active_port_id(imx_ldb_ch->child, encoder);
212 u32 bus_format = imx_ldb_ch->bus_format;
213
214 if (mux < 0 || mux >= ARRAY_SIZE(ldb->clk_sel)) {
215 dev_warn(ldb->dev, "%s: invalid mux %d\n", __func__, mux);
216 return;
217 }
218
219 if (mode->clock > 170000) {
220 dev_warn(ldb->dev,
221 "%s: mode exceeds 170 MHz pixel clock\n", __func__);
222 }
223 if (mode->clock > 85000 && !dual) {
224 dev_warn(ldb->dev,
225 "%s: mode exceeds 85 MHz pixel clock\n", __func__);
226 }
227
228 if (!IS_ALIGNED(mode->hdisplay, 8)) {
229 dev_warn(ldb->dev,
230 "%s: hdisplay does not align to 8 byte\n", __func__);
231 }
232
233 if (dual) {
234 serial_clk = 3500UL * mode->clock;
235 imx_ldb_set_clock(ldb, mux, 0, serial_clk, di_clk);
236 imx_ldb_set_clock(ldb, mux, 1, serial_clk, di_clk);
237 } else {
238 serial_clk = 7000UL * mode->clock;
239 imx_ldb_set_clock(ldb, mux, imx_ldb_ch->chno, serial_clk,
240 di_clk);
241 }
242
243 /* FIXME - assumes straight connections DI0 --> CH0, DI1 --> CH1 */
244 if (imx_ldb_ch == &ldb->channel[0] || dual) {
245 if (mode->flags & DRM_MODE_FLAG_NVSYNC)
246 ldb->ldb_ctrl |= LDB_DI0_VS_POL_ACT_LOW;
247 else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
248 ldb->ldb_ctrl &= ~LDB_DI0_VS_POL_ACT_LOW;
249 }
250 if (imx_ldb_ch == &ldb->channel[1] || dual) {
251 if (mode->flags & DRM_MODE_FLAG_NVSYNC)
252 ldb->ldb_ctrl |= LDB_DI1_VS_POL_ACT_LOW;
253 else if (mode->flags & DRM_MODE_FLAG_PVSYNC)
254 ldb->ldb_ctrl &= ~LDB_DI1_VS_POL_ACT_LOW;
255 }
256
257 if (!bus_format) {
258 struct drm_connector *connector = connector_state->connector;
259 struct drm_display_info *di = &connector->display_info;
260
261 if (di->num_bus_formats)
262 bus_format = di->bus_formats[0];
263 }
264 imx_ldb_ch_set_bus_format(imx_ldb_ch, bus_format);
265 }
266
imx_ldb_encoder_disable(struct drm_encoder * encoder)267 static void imx_ldb_encoder_disable(struct drm_encoder *encoder)
268 {
269 struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
270 struct imx_ldb *ldb = imx_ldb_ch->ldb;
271 int dual = ldb->ldb_ctrl & LDB_SPLIT_MODE_EN;
272 int mux, ret;
273
274 if (imx_ldb_ch == &ldb->channel[0] || dual)
275 ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
276 if (imx_ldb_ch == &ldb->channel[1] || dual)
277 ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
278
279 regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
280
281 if (dual) {
282 clk_disable_unprepare(ldb->clk[0]);
283 clk_disable_unprepare(ldb->clk[1]);
284 }
285
286 if (ldb->lvds_mux) {
287 const struct bus_mux *lvds_mux = NULL;
288
289 if (imx_ldb_ch == &ldb->channel[0])
290 lvds_mux = &ldb->lvds_mux[0];
291 else if (imx_ldb_ch == &ldb->channel[1])
292 lvds_mux = &ldb->lvds_mux[1];
293
294 regmap_read(ldb->regmap, lvds_mux->reg, &mux);
295 mux &= lvds_mux->mask;
296 mux >>= lvds_mux->shift;
297 } else {
298 mux = (imx_ldb_ch == &ldb->channel[0]) ? 0 : 1;
299 }
300
301 /* set display clock mux back to original input clock */
302 ret = clk_set_parent(ldb->clk_sel[mux], ldb->clk_parent[mux]);
303 if (ret)
304 dev_err(ldb->dev,
305 "unable to set di%d parent clock to original parent\n",
306 mux);
307 }
308
imx_ldb_encoder_atomic_check(struct drm_encoder * encoder,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state)309 static int imx_ldb_encoder_atomic_check(struct drm_encoder *encoder,
310 struct drm_crtc_state *crtc_state,
311 struct drm_connector_state *conn_state)
312 {
313 struct imx_crtc_state *imx_crtc_state = to_imx_crtc_state(crtc_state);
314 struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
315 struct drm_display_info *di = &conn_state->connector->display_info;
316 u32 bus_format = imx_ldb_ch->bus_format;
317
318 /* Bus format description in DT overrides connector display info. */
319 if (!bus_format && di->num_bus_formats) {
320 bus_format = di->bus_formats[0];
321 } else {
322 bus_format = imx_ldb_ch->bus_format;
323 }
324
325 imx_crtc_state->bus_flags = di->bus_flags;
326
327 switch (bus_format) {
328 case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
329 imx_crtc_state->bus_format = MEDIA_BUS_FMT_RGB666_1X18;
330 break;
331 case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
332 case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
333 imx_crtc_state->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
334 break;
335 default:
336 return -EINVAL;
337 }
338
339 imx_crtc_state->di_hsync_pin = 2;
340 imx_crtc_state->di_vsync_pin = 3;
341
342 return 0;
343 }
344
345
346 static const struct drm_encoder_helper_funcs imx_ldb_encoder_helper_funcs = {
347 .atomic_mode_set = imx_ldb_encoder_atomic_mode_set,
348 .enable = imx_ldb_encoder_enable,
349 .disable = imx_ldb_encoder_disable,
350 .atomic_check = imx_ldb_encoder_atomic_check,
351 };
352
imx_ldb_get_clk(struct imx_ldb * ldb,int chno)353 static int imx_ldb_get_clk(struct imx_ldb *ldb, int chno)
354 {
355 char clkname[16];
356
357 snprintf(clkname, sizeof(clkname), "di%d", chno);
358 ldb->clk[chno] = devm_clk_get(ldb->dev, clkname);
359 if (IS_ERR(ldb->clk[chno]))
360 return PTR_ERR(ldb->clk[chno]);
361
362 snprintf(clkname, sizeof(clkname), "di%d_pll", chno);
363 ldb->clk_pll[chno] = devm_clk_get(ldb->dev, clkname);
364
365 return PTR_ERR_OR_ZERO(ldb->clk_pll[chno]);
366 }
367
imx_ldb_register(struct drm_device * drm,struct imx_ldb_channel * imx_ldb_ch)368 static int imx_ldb_register(struct drm_device *drm,
369 struct imx_ldb_channel *imx_ldb_ch)
370 {
371 struct imx_ldb *ldb = imx_ldb_ch->ldb;
372 struct imx_ldb_encoder *ldb_encoder;
373 struct drm_connector *connector;
374 struct drm_encoder *encoder;
375 int ret;
376
377 ldb_encoder = drmm_simple_encoder_alloc(drm, struct imx_ldb_encoder,
378 encoder, DRM_MODE_ENCODER_LVDS);
379 if (IS_ERR(ldb_encoder))
380 return PTR_ERR(ldb_encoder);
381
382 ldb_encoder->channel = imx_ldb_ch;
383 encoder = &ldb_encoder->encoder;
384
385 ret = imx_drm_encoder_parse_of(drm, encoder, imx_ldb_ch->child);
386 if (ret)
387 return ret;
388
389 ret = imx_ldb_get_clk(ldb, imx_ldb_ch->chno);
390 if (ret)
391 return ret;
392
393 if (ldb->ldb_ctrl & LDB_SPLIT_MODE_EN) {
394 ret = imx_ldb_get_clk(ldb, 1);
395 if (ret)
396 return ret;
397 }
398
399 drm_encoder_helper_add(encoder, &imx_ldb_encoder_helper_funcs);
400
401 ret = drm_bridge_attach(encoder, imx_ldb_ch->bridge, NULL,
402 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
403 if (ret)
404 return ret;
405
406 connector = drm_bridge_connector_init(drm, encoder);
407 if (IS_ERR(connector))
408 return PTR_ERR(connector);
409
410 drm_connector_attach_encoder(connector, encoder);
411
412 return 0;
413 }
414
415 struct imx_ldb_bit_mapping {
416 u32 bus_format;
417 u32 datawidth;
418 const char * const mapping;
419 };
420
421 static const struct imx_ldb_bit_mapping imx_ldb_bit_mappings[] = {
422 { MEDIA_BUS_FMT_RGB666_1X7X3_SPWG, 18, "spwg" },
423 { MEDIA_BUS_FMT_RGB888_1X7X4_SPWG, 24, "spwg" },
424 { MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA, 24, "jeida" },
425 };
426
of_get_bus_format(struct device * dev,struct device_node * np)427 static u32 of_get_bus_format(struct device *dev, struct device_node *np)
428 {
429 const char *bm;
430 u32 datawidth = 0;
431 int ret, i;
432
433 ret = of_property_read_string(np, "fsl,data-mapping", &bm);
434 if (ret < 0)
435 return ret;
436
437 of_property_read_u32(np, "fsl,data-width", &datawidth);
438
439 for (i = 0; i < ARRAY_SIZE(imx_ldb_bit_mappings); i++) {
440 if (!strcasecmp(bm, imx_ldb_bit_mappings[i].mapping) &&
441 datawidth == imx_ldb_bit_mappings[i].datawidth)
442 return imx_ldb_bit_mappings[i].bus_format;
443 }
444
445 dev_err(dev, "invalid data mapping: %d-bit \"%s\"\n", datawidth, bm);
446
447 return -ENOENT;
448 }
449
450 static struct bus_mux imx6q_lvds_mux[2] = {
451 {
452 .reg = IOMUXC_GPR3,
453 .shift = 6,
454 .mask = IMX6Q_GPR3_LVDS0_MUX_CTL_MASK,
455 }, {
456 .reg = IOMUXC_GPR3,
457 .shift = 8,
458 .mask = IMX6Q_GPR3_LVDS1_MUX_CTL_MASK,
459 }
460 };
461
462 /*
463 * For a device declaring compatible = "fsl,imx6q-ldb", "fsl,imx53-ldb",
464 * of_match_device will walk through this list and take the first entry
465 * matching any of its compatible values. Therefore, the more generic
466 * entries (in this case fsl,imx53-ldb) need to be ordered last.
467 */
468 static const struct of_device_id imx_ldb_dt_ids[] = {
469 { .compatible = "fsl,imx6q-ldb", .data = imx6q_lvds_mux, },
470 { .compatible = "fsl,imx53-ldb", .data = NULL, },
471 { }
472 };
473 MODULE_DEVICE_TABLE(of, imx_ldb_dt_ids);
474
imx_ldb_bind(struct device * dev,struct device * master,void * data)475 static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
476 {
477 struct drm_device *drm = data;
478 struct imx_ldb *imx_ldb = dev_get_drvdata(dev);
479 int ret;
480 int i;
481
482 for (i = 0; i < 2; i++) {
483 struct imx_ldb_channel *channel = &imx_ldb->channel[i];
484
485 if (!channel->ldb)
486 continue;
487
488 ret = imx_ldb_register(drm, channel);
489 if (ret)
490 return ret;
491 }
492
493 return 0;
494 }
495
496 static const struct component_ops imx_ldb_ops = {
497 .bind = imx_ldb_bind,
498 };
499
imx_ldb_probe(struct platform_device * pdev)500 static int imx_ldb_probe(struct platform_device *pdev)
501 {
502 struct device *dev = &pdev->dev;
503 struct device_node *np = dev->of_node;
504 struct device_node *child;
505 struct imx_ldb *imx_ldb;
506 int dual;
507 int ret;
508 int i;
509
510 imx_ldb = devm_kzalloc(dev, sizeof(*imx_ldb), GFP_KERNEL);
511 if (!imx_ldb)
512 return -ENOMEM;
513
514 imx_ldb->regmap = syscon_regmap_lookup_by_phandle(np, "gpr");
515 if (IS_ERR(imx_ldb->regmap)) {
516 dev_err(dev, "failed to get parent regmap\n");
517 return PTR_ERR(imx_ldb->regmap);
518 }
519
520 /* disable LDB by resetting the control register to POR default */
521 regmap_write(imx_ldb->regmap, IOMUXC_GPR2, 0);
522
523 imx_ldb->dev = dev;
524 imx_ldb->lvds_mux = device_get_match_data(dev);
525
526 dual = of_property_read_bool(np, "fsl,dual-channel");
527 if (dual)
528 imx_ldb->ldb_ctrl |= LDB_SPLIT_MODE_EN;
529
530 /*
531 * There are three different possible clock mux configurations:
532 * i.MX53: ipu1_di0_sel, ipu1_di1_sel
533 * i.MX6q: ipu1_di0_sel, ipu1_di1_sel, ipu2_di0_sel, ipu2_di1_sel
534 * i.MX6dl: ipu1_di0_sel, ipu1_di1_sel, lcdif_sel
535 * Map them all to di0_sel...di3_sel.
536 */
537 for (i = 0; i < 4; i++) {
538 char clkname[16];
539
540 snprintf(clkname, sizeof(clkname), "di%d_sel", i);
541 imx_ldb->clk_sel[i] = devm_clk_get(imx_ldb->dev, clkname);
542 if (IS_ERR(imx_ldb->clk_sel[i])) {
543 ret = PTR_ERR(imx_ldb->clk_sel[i]);
544 imx_ldb->clk_sel[i] = NULL;
545 break;
546 }
547
548 imx_ldb->clk_parent[i] = clk_get_parent(imx_ldb->clk_sel[i]);
549 }
550 if (i == 0)
551 return ret;
552
553 for_each_child_of_node(np, child) {
554 struct imx_ldb_channel *channel;
555 int bus_format;
556
557 ret = of_property_read_u32(child, "reg", &i);
558 if (ret || i < 0 || i > 1) {
559 ret = -EINVAL;
560 goto free_child;
561 }
562
563 if (!of_device_is_available(child))
564 continue;
565
566 if (dual && i > 0) {
567 dev_warn(dev, "dual-channel mode, ignoring second output\n");
568 continue;
569 }
570
571 channel = &imx_ldb->channel[i];
572 channel->ldb = imx_ldb;
573 channel->chno = i;
574
575 /*
576 * The output port is port@4 with an external 4-port mux or
577 * port@2 with the internal 2-port mux.
578 */
579 channel->bridge = devm_drm_of_get_bridge(dev, child,
580 imx_ldb->lvds_mux ? 4 : 2, 0);
581 if (IS_ERR(channel->bridge)) {
582 ret = PTR_ERR(channel->bridge);
583 if (ret != -ENODEV)
584 goto free_child;
585 channel->bridge = NULL;
586 }
587
588 bus_format = of_get_bus_format(dev, child);
589 /*
590 * If no bus format was specified in the device tree,
591 * we can still get it from the connected panel later.
592 */
593 if (bus_format == -EINVAL && channel->bridge)
594 bus_format = 0;
595 if (bus_format < 0) {
596 dev_err(dev, "could not determine data mapping: %d\n",
597 bus_format);
598 ret = bus_format;
599 goto free_child;
600 }
601 channel->bus_format = bus_format;
602
603 /*
604 * legacy bridge doesn't handle bus_format, so create it after
605 * checking the bus_format property.
606 */
607 if (!channel->bridge) {
608 channel->bridge = devm_imx_drm_legacy_bridge(dev, child,
609 DRM_MODE_CONNECTOR_LVDS);
610 if (IS_ERR(channel->bridge)) {
611 ret = PTR_ERR(channel->bridge);
612 goto free_child;
613 }
614 }
615
616 channel->child = child;
617 }
618
619 platform_set_drvdata(pdev, imx_ldb);
620
621 return component_add(&pdev->dev, &imx_ldb_ops);
622
623 free_child:
624 of_node_put(child);
625 return ret;
626 }
627
imx_ldb_remove(struct platform_device * pdev)628 static void imx_ldb_remove(struct platform_device *pdev)
629 {
630 component_del(&pdev->dev, &imx_ldb_ops);
631 }
632
633 static struct platform_driver imx_ldb_driver = {
634 .probe = imx_ldb_probe,
635 .remove = imx_ldb_remove,
636 .driver = {
637 .of_match_table = imx_ldb_dt_ids,
638 .name = DRIVER_NAME,
639 },
640 };
641
642 module_platform_driver(imx_ldb_driver);
643
644 MODULE_DESCRIPTION("i.MX LVDS driver");
645 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
646 MODULE_LICENSE("GPL");
647 MODULE_ALIAS("platform:" DRIVER_NAME);
648