xref: /linux/drivers/gpu/drm/bridge/imx/imx8qm-ldb.c (revision 6f7e6393d1ce636bb7ec77a7fe7b77458fddf701)
1 // SPDX-License-Identifier: GPL-2.0+
2 
3 /*
4  * Copyright 2020 NXP
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/media-bus-format.h>
9 #include <linux/mfd/syscon.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/of_graph.h>
13 #include <linux/phy/phy.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/regmap.h>
17 
18 #include <drm/drm_atomic_state_helper.h>
19 #include <drm/drm_bridge.h>
20 #include <drm/drm_connector.h>
21 #include <drm/drm_fourcc.h>
22 #include <drm/drm_of.h>
23 #include <drm/drm_print.h>
24 
25 #include "imx-ldb-helper.h"
26 
27 #define  LDB_CH0_10BIT_EN		BIT(22)
28 #define  LDB_CH1_10BIT_EN		BIT(23)
29 #define  LDB_CH0_DATA_WIDTH_24BIT	BIT(24)
30 #define  LDB_CH1_DATA_WIDTH_24BIT	BIT(26)
31 #define  LDB_CH0_DATA_WIDTH_30BIT	(2 << 24)
32 #define  LDB_CH1_DATA_WIDTH_30BIT	(2 << 26)
33 
34 #define SS_CTRL				0x20
35 #define  CH_HSYNC_M(id)			BIT(0 + ((id) * 2))
36 #define  CH_VSYNC_M(id)			BIT(1 + ((id) * 2))
37 #define  CH_PHSYNC(id)			BIT(0 + ((id) * 2))
38 #define  CH_PVSYNC(id)			BIT(1 + ((id) * 2))
39 
40 #define DRIVER_NAME			"imx8qm-ldb"
41 
42 struct imx8qm_ldb_channel {
43 	struct ldb_channel base;
44 	struct phy *phy;
45 };
46 
47 struct imx8qm_ldb {
48 	struct ldb base;
49 	struct device *dev;
50 	struct imx8qm_ldb_channel *channel[MAX_LDB_CHAN_NUM];
51 	struct clk *clk_pixel;
52 	struct clk *clk_bypass;
53 	int active_chno;
54 };
55 
56 static inline struct imx8qm_ldb_channel *
57 base_to_imx8qm_ldb_channel(struct ldb_channel *base)
58 {
59 	return container_of(base, struct imx8qm_ldb_channel, base);
60 }
61 
62 static inline struct imx8qm_ldb *base_to_imx8qm_ldb(struct ldb *base)
63 {
64 	return container_of(base, struct imx8qm_ldb, base);
65 }
66 
67 static void imx8qm_ldb_set_phy_cfg(struct imx8qm_ldb *imx8qm_ldb,
68 				   unsigned long di_clk,
69 				   bool is_split, bool is_slave,
70 				   struct phy_configure_opts_lvds *phy_cfg)
71 {
72 	phy_cfg->bits_per_lane_and_dclk_cycle = 7;
73 	phy_cfg->lanes = 4;
74 	phy_cfg->differential_clk_rate = is_split ? di_clk / 2 : di_clk;
75 	phy_cfg->is_slave = is_slave;
76 }
77 
78 static int imx8qm_ldb_bridge_atomic_check(struct drm_bridge *bridge,
79 					  struct drm_bridge_state *bridge_state,
80 					  struct drm_crtc_state *crtc_state,
81 					  struct drm_connector_state *conn_state)
82 {
83 	struct ldb_channel *ldb_ch = bridge->driver_private;
84 	struct ldb *ldb = ldb_ch->ldb;
85 	struct imx8qm_ldb_channel *imx8qm_ldb_ch =
86 					base_to_imx8qm_ldb_channel(ldb_ch);
87 	struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
88 	struct drm_display_mode *adj = &crtc_state->adjusted_mode;
89 	unsigned long di_clk = adj->clock * 1000;
90 	bool is_split = ldb_channel_is_split_link(ldb_ch);
91 	union phy_configure_opts opts = { };
92 	struct phy_configure_opts_lvds *phy_cfg = &opts.lvds;
93 	int ret;
94 
95 	ret = ldb_bridge_atomic_check_helper(bridge, bridge_state,
96 					     crtc_state, conn_state);
97 	if (ret)
98 		return ret;
99 
100 	imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, false, phy_cfg);
101 	ret = phy_validate(imx8qm_ldb_ch->phy, PHY_MODE_LVDS, 0, &opts);
102 	if (ret < 0) {
103 		DRM_DEV_DEBUG_DRIVER(imx8qm_ldb->dev,
104 				     "failed to validate PHY: %d\n", ret);
105 		return ret;
106 	}
107 
108 	if (is_split) {
109 		imx8qm_ldb_ch =
110 			imx8qm_ldb->channel[imx8qm_ldb->active_chno ^ 1];
111 		imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, true,
112 				       phy_cfg);
113 		ret = phy_validate(imx8qm_ldb_ch->phy, PHY_MODE_LVDS, 0, &opts);
114 		if (ret < 0) {
115 			DRM_DEV_DEBUG_DRIVER(imx8qm_ldb->dev,
116 					     "failed to validate slave PHY: %d\n",
117 					     ret);
118 			return ret;
119 		}
120 	}
121 
122 	return ret;
123 }
124 
125 static void
126 imx8qm_ldb_bridge_mode_set(struct drm_bridge *bridge,
127 			   const struct drm_display_mode *mode,
128 			   const struct drm_display_mode *adjusted_mode)
129 {
130 	struct ldb_channel *ldb_ch = bridge->driver_private;
131 	struct ldb *ldb = ldb_ch->ldb;
132 	struct imx8qm_ldb_channel *imx8qm_ldb_ch =
133 					base_to_imx8qm_ldb_channel(ldb_ch);
134 	struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
135 	struct device *dev = imx8qm_ldb->dev;
136 	unsigned long di_clk = adjusted_mode->clock * 1000;
137 	bool is_split = ldb_channel_is_split_link(ldb_ch);
138 	union phy_configure_opts opts = { };
139 	struct phy_configure_opts_lvds *phy_cfg = &opts.lvds;
140 	u32 chno = ldb_ch->chno;
141 	int ret;
142 
143 	ret = pm_runtime_get_sync(dev);
144 	if (ret < 0)
145 		DRM_DEV_ERROR(dev, "failed to get runtime PM sync: %d\n", ret);
146 
147 	ret = phy_init(imx8qm_ldb_ch->phy);
148 	if (ret < 0)
149 		DRM_DEV_ERROR(dev, "failed to initialize PHY: %d\n", ret);
150 
151 	clk_set_rate(imx8qm_ldb->clk_bypass, di_clk);
152 	clk_set_rate(imx8qm_ldb->clk_pixel, di_clk);
153 
154 	imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, false, phy_cfg);
155 	ret = phy_configure(imx8qm_ldb_ch->phy, &opts);
156 	if (ret < 0)
157 		DRM_DEV_ERROR(dev, "failed to configure PHY: %d\n", ret);
158 
159 	if (is_split) {
160 		imx8qm_ldb_ch =
161 			imx8qm_ldb->channel[imx8qm_ldb->active_chno ^ 1];
162 		imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, true,
163 				       phy_cfg);
164 		ret = phy_configure(imx8qm_ldb_ch->phy, &opts);
165 		if (ret < 0)
166 			DRM_DEV_ERROR(dev, "failed to configure slave PHY: %d\n",
167 				      ret);
168 	}
169 
170 	/* input VSYNC signal from pixel link is active low */
171 	if (ldb_ch->chno == 0 || is_split)
172 		ldb->ldb_ctrl |= LDB_DI0_VS_POL_ACT_LOW;
173 	if (ldb_ch->chno == 1 || is_split)
174 		ldb->ldb_ctrl |= LDB_DI1_VS_POL_ACT_LOW;
175 
176 	switch (ldb_ch->out_bus_format) {
177 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
178 		break;
179 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
180 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
181 		if (ldb_ch->chno == 0 || is_split)
182 			ldb->ldb_ctrl |= LDB_CH0_DATA_WIDTH_24BIT;
183 		if (ldb_ch->chno == 1 || is_split)
184 			ldb->ldb_ctrl |= LDB_CH1_DATA_WIDTH_24BIT;
185 		break;
186 	}
187 
188 	ldb_bridge_mode_set_helper(bridge, mode, adjusted_mode);
189 
190 	if (adjusted_mode->flags & DRM_MODE_FLAG_NVSYNC)
191 		regmap_update_bits(ldb->regmap, SS_CTRL, CH_VSYNC_M(chno), 0);
192 	else if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
193 		regmap_update_bits(ldb->regmap, SS_CTRL,
194 				   CH_VSYNC_M(chno), CH_PVSYNC(chno));
195 
196 	if (adjusted_mode->flags & DRM_MODE_FLAG_NHSYNC)
197 		regmap_update_bits(ldb->regmap, SS_CTRL, CH_HSYNC_M(chno), 0);
198 	else if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
199 		regmap_update_bits(ldb->regmap, SS_CTRL,
200 				   CH_HSYNC_M(chno), CH_PHSYNC(chno));
201 }
202 
203 static void imx8qm_ldb_bridge_atomic_enable(struct drm_bridge *bridge,
204 					    struct drm_atomic_state *state)
205 {
206 	struct ldb_channel *ldb_ch = bridge->driver_private;
207 	struct ldb *ldb = ldb_ch->ldb;
208 	struct imx8qm_ldb_channel *imx8qm_ldb_ch =
209 					base_to_imx8qm_ldb_channel(ldb_ch);
210 	struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
211 	struct device *dev = imx8qm_ldb->dev;
212 	bool is_split = ldb_channel_is_split_link(ldb_ch);
213 	int ret;
214 
215 	clk_prepare_enable(imx8qm_ldb->clk_pixel);
216 	clk_prepare_enable(imx8qm_ldb->clk_bypass);
217 
218 	/* both DI0 and DI1 connect with pixel link, so ok to use DI0 only */
219 	if (ldb_ch->chno == 0 || is_split) {
220 		ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
221 		ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI0;
222 	}
223 	if (ldb_ch->chno == 1 || is_split) {
224 		ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
225 		ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI0;
226 	}
227 
228 	if (is_split) {
229 		ret = phy_power_on(imx8qm_ldb->channel[0]->phy);
230 		if (ret)
231 			DRM_DEV_ERROR(dev,
232 				      "failed to power on channel0 PHY: %d\n",
233 				      ret);
234 
235 		ret = phy_power_on(imx8qm_ldb->channel[1]->phy);
236 		if (ret)
237 			DRM_DEV_ERROR(dev,
238 				      "failed to power on channel1 PHY: %d\n",
239 				      ret);
240 	} else {
241 		ret = phy_power_on(imx8qm_ldb_ch->phy);
242 		if (ret)
243 			DRM_DEV_ERROR(dev, "failed to power on PHY: %d\n", ret);
244 	}
245 
246 	ldb_bridge_enable_helper(bridge);
247 }
248 
249 static void imx8qm_ldb_bridge_atomic_disable(struct drm_bridge *bridge,
250 					     struct drm_atomic_state *state)
251 {
252 	struct ldb_channel *ldb_ch = bridge->driver_private;
253 	struct ldb *ldb = ldb_ch->ldb;
254 	struct imx8qm_ldb_channel *imx8qm_ldb_ch =
255 					base_to_imx8qm_ldb_channel(ldb_ch);
256 	struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
257 	struct device *dev = imx8qm_ldb->dev;
258 	bool is_split = ldb_channel_is_split_link(ldb_ch);
259 	int ret;
260 
261 	ldb_bridge_disable_helper(bridge);
262 
263 	if (is_split) {
264 		ret = phy_power_off(imx8qm_ldb->channel[0]->phy);
265 		if (ret)
266 			DRM_DEV_ERROR(dev,
267 				      "failed to power off channel0 PHY: %d\n",
268 				      ret);
269 		ret = phy_power_off(imx8qm_ldb->channel[1]->phy);
270 		if (ret)
271 			DRM_DEV_ERROR(dev,
272 				      "failed to power off channel1 PHY: %d\n",
273 				      ret);
274 	} else {
275 		ret = phy_power_off(imx8qm_ldb_ch->phy);
276 		if (ret)
277 			DRM_DEV_ERROR(dev, "failed to power off PHY: %d\n", ret);
278 	}
279 
280 	clk_disable_unprepare(imx8qm_ldb->clk_bypass);
281 	clk_disable_unprepare(imx8qm_ldb->clk_pixel);
282 
283 	pm_runtime_put(dev);
284 }
285 
286 static const u32 imx8qm_ldb_bus_output_fmts[] = {
287 	MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
288 	MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
289 	MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA,
290 	MEDIA_BUS_FMT_FIXED,
291 };
292 
293 static bool imx8qm_ldb_bus_output_fmt_supported(u32 fmt)
294 {
295 	int i;
296 
297 	for (i = 0; i < ARRAY_SIZE(imx8qm_ldb_bus_output_fmts); i++) {
298 		if (imx8qm_ldb_bus_output_fmts[i] == fmt)
299 			return true;
300 	}
301 
302 	return false;
303 }
304 
305 static u32 *
306 imx8qm_ldb_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
307 					    struct drm_bridge_state *bridge_state,
308 					    struct drm_crtc_state *crtc_state,
309 					    struct drm_connector_state *conn_state,
310 					    u32 output_fmt,
311 					    unsigned int *num_input_fmts)
312 {
313 	struct drm_display_info *di;
314 	const struct drm_format_info *finfo;
315 	u32 *input_fmts;
316 
317 	if (!imx8qm_ldb_bus_output_fmt_supported(output_fmt))
318 		return NULL;
319 
320 	*num_input_fmts = 1;
321 
322 	input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
323 	if (!input_fmts)
324 		return NULL;
325 
326 	switch (output_fmt) {
327 	case MEDIA_BUS_FMT_FIXED:
328 		di = &conn_state->connector->display_info;
329 
330 		/*
331 		 * Look at the first bus format to determine input format.
332 		 * Default to MEDIA_BUS_FMT_RGB888_1X36_CPADLO, if no match.
333 		 */
334 		if (di->num_bus_formats) {
335 			finfo = drm_format_info(di->bus_formats[0]);
336 
337 			input_fmts[0] = finfo->depth == 18 ?
338 					MEDIA_BUS_FMT_RGB666_1X36_CPADLO :
339 					MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
340 		} else {
341 			input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
342 		}
343 		break;
344 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
345 		input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X36_CPADLO;
346 		break;
347 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
348 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
349 		input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
350 		break;
351 	default:
352 		kfree(input_fmts);
353 		input_fmts = NULL;
354 		break;
355 	}
356 
357 	return input_fmts;
358 }
359 
360 static u32 *
361 imx8qm_ldb_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
362 					     struct drm_bridge_state *bridge_state,
363 					     struct drm_crtc_state *crtc_state,
364 					     struct drm_connector_state *conn_state,
365 					     unsigned int *num_output_fmts)
366 {
367 	*num_output_fmts = ARRAY_SIZE(imx8qm_ldb_bus_output_fmts);
368 	return kmemdup(imx8qm_ldb_bus_output_fmts,
369 			sizeof(imx8qm_ldb_bus_output_fmts), GFP_KERNEL);
370 }
371 
372 static enum drm_mode_status
373 imx8qm_ldb_bridge_mode_valid(struct drm_bridge *bridge,
374 			     const struct drm_display_info *info,
375 			     const struct drm_display_mode *mode)
376 {
377 	struct ldb_channel *ldb_ch = bridge->driver_private;
378 	bool is_single = ldb_channel_is_single_link(ldb_ch);
379 
380 	if (mode->clock > 300000)
381 		return MODE_CLOCK_HIGH;
382 
383 	if (mode->clock > 150000 && is_single)
384 		return MODE_CLOCK_HIGH;
385 
386 	return MODE_OK;
387 }
388 
389 static const struct drm_bridge_funcs imx8qm_ldb_bridge_funcs = {
390 	.atomic_duplicate_state	= drm_atomic_helper_bridge_duplicate_state,
391 	.atomic_destroy_state	= drm_atomic_helper_bridge_destroy_state,
392 	.atomic_reset		= drm_atomic_helper_bridge_reset,
393 	.mode_valid		= imx8qm_ldb_bridge_mode_valid,
394 	.attach			= ldb_bridge_attach_helper,
395 	.atomic_check		= imx8qm_ldb_bridge_atomic_check,
396 	.mode_set		= imx8qm_ldb_bridge_mode_set,
397 	.atomic_enable		= imx8qm_ldb_bridge_atomic_enable,
398 	.atomic_disable		= imx8qm_ldb_bridge_atomic_disable,
399 	.atomic_get_input_bus_fmts =
400 			imx8qm_ldb_bridge_atomic_get_input_bus_fmts,
401 	.atomic_get_output_bus_fmts =
402 			imx8qm_ldb_bridge_atomic_get_output_bus_fmts,
403 };
404 
405 static int imx8qm_ldb_get_phy(struct imx8qm_ldb *imx8qm_ldb)
406 {
407 	struct imx8qm_ldb_channel *imx8qm_ldb_ch;
408 	struct ldb_channel *ldb_ch;
409 	struct device *dev = imx8qm_ldb->dev;
410 	int i, ret;
411 
412 	for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
413 		imx8qm_ldb_ch = imx8qm_ldb->channel[i];
414 		ldb_ch = &imx8qm_ldb_ch->base;
415 
416 		if (!ldb_ch->is_available)
417 			continue;
418 
419 		imx8qm_ldb_ch->phy = devm_of_phy_get(dev, ldb_ch->np,
420 						     "lvds_phy");
421 		if (IS_ERR(imx8qm_ldb_ch->phy)) {
422 			ret = PTR_ERR(imx8qm_ldb_ch->phy);
423 			if (ret != -EPROBE_DEFER)
424 				DRM_DEV_ERROR(dev,
425 					      "failed to get channel%d PHY: %d\n",
426 					      i, ret);
427 			return ret;
428 		}
429 	}
430 
431 	return 0;
432 }
433 
434 static int imx8qm_ldb_probe(struct platform_device *pdev)
435 {
436 	struct device *dev = &pdev->dev;
437 	struct imx8qm_ldb *imx8qm_ldb;
438 	struct imx8qm_ldb_channel *imx8qm_ldb_ch;
439 	struct ldb *ldb;
440 	struct ldb_channel *ldb_ch;
441 	struct device_node *port1, *port2;
442 	int pixel_order;
443 	int ret, i;
444 
445 	imx8qm_ldb = devm_kzalloc(dev, sizeof(*imx8qm_ldb), GFP_KERNEL);
446 	if (!imx8qm_ldb)
447 		return -ENOMEM;
448 
449 	for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
450 		imx8qm_ldb->channel[i] =
451 			devm_drm_bridge_alloc(dev, struct imx8qm_ldb_channel, base.bridge,
452 					      &imx8qm_ldb_bridge_funcs);
453 		if (IS_ERR(imx8qm_ldb->channel[i]))
454 			return PTR_ERR(imx8qm_ldb->channel[i]);
455 	}
456 
457 	imx8qm_ldb->clk_pixel = devm_clk_get(dev, "pixel");
458 	if (IS_ERR(imx8qm_ldb->clk_pixel)) {
459 		ret = PTR_ERR(imx8qm_ldb->clk_pixel);
460 		if (ret != -EPROBE_DEFER)
461 			DRM_DEV_ERROR(dev,
462 				      "failed to get pixel clock: %d\n", ret);
463 		return ret;
464 	}
465 
466 	imx8qm_ldb->clk_bypass = devm_clk_get(dev, "bypass");
467 	if (IS_ERR(imx8qm_ldb->clk_bypass)) {
468 		ret = PTR_ERR(imx8qm_ldb->clk_bypass);
469 		if (ret != -EPROBE_DEFER)
470 			DRM_DEV_ERROR(dev,
471 				      "failed to get bypass clock: %d\n", ret);
472 		return ret;
473 	}
474 
475 	imx8qm_ldb->dev = dev;
476 
477 	ldb = &imx8qm_ldb->base;
478 	ldb->dev = dev;
479 	ldb->ctrl_reg = 0xe0;
480 
481 	for (i = 0; i < MAX_LDB_CHAN_NUM; i++)
482 		ldb->channel[i] = &imx8qm_ldb->channel[i]->base;
483 
484 	ret = ldb_init_helper(ldb);
485 	if (ret)
486 		return ret;
487 
488 	if (ldb->available_ch_cnt == 0) {
489 		DRM_DEV_DEBUG_DRIVER(dev, "no available channel\n");
490 		return 0;
491 	}
492 
493 	if (ldb->available_ch_cnt == 2) {
494 		port1 = of_graph_get_port_by_id(ldb->channel[0]->np, 1);
495 		port2 = of_graph_get_port_by_id(ldb->channel[1]->np, 1);
496 		pixel_order =
497 			drm_of_lvds_get_dual_link_pixel_order(port1, port2);
498 		of_node_put(port1);
499 		of_node_put(port2);
500 
501 		if (pixel_order != DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS) {
502 			DRM_DEV_ERROR(dev, "invalid dual link pixel order: %d\n",
503 				      pixel_order);
504 			return -EINVAL;
505 		}
506 
507 		imx8qm_ldb->active_chno = 0;
508 		imx8qm_ldb_ch = imx8qm_ldb->channel[0];
509 		ldb_ch = &imx8qm_ldb_ch->base;
510 		ldb_ch->link_type = pixel_order;
511 	} else {
512 		for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
513 			imx8qm_ldb_ch = imx8qm_ldb->channel[i];
514 			ldb_ch = &imx8qm_ldb_ch->base;
515 
516 			if (ldb_ch->is_available) {
517 				imx8qm_ldb->active_chno = ldb_ch->chno;
518 				break;
519 			}
520 		}
521 	}
522 
523 	ret = imx8qm_ldb_get_phy(imx8qm_ldb);
524 	if (ret)
525 		return ret;
526 
527 	ret = ldb_find_next_bridge_helper(ldb);
528 	if (ret)
529 		return ret;
530 
531 	platform_set_drvdata(pdev, imx8qm_ldb);
532 	pm_runtime_enable(dev);
533 
534 	ldb_add_bridge_helper(ldb);
535 
536 	return ret;
537 }
538 
539 static void imx8qm_ldb_remove(struct platform_device *pdev)
540 {
541 	struct imx8qm_ldb *imx8qm_ldb = platform_get_drvdata(pdev);
542 	struct ldb *ldb = &imx8qm_ldb->base;
543 
544 	ldb_remove_bridge_helper(ldb);
545 
546 	pm_runtime_disable(&pdev->dev);
547 }
548 
549 static int imx8qm_ldb_runtime_suspend(struct device *dev)
550 {
551 	return 0;
552 }
553 
554 static int imx8qm_ldb_runtime_resume(struct device *dev)
555 {
556 	struct imx8qm_ldb *imx8qm_ldb = dev_get_drvdata(dev);
557 	struct ldb *ldb = &imx8qm_ldb->base;
558 
559 	/* disable LDB by resetting the control register to POR default */
560 	regmap_write(ldb->regmap, ldb->ctrl_reg, 0);
561 
562 	return 0;
563 }
564 
565 static const struct dev_pm_ops imx8qm_ldb_pm_ops = {
566 	RUNTIME_PM_OPS(imx8qm_ldb_runtime_suspend, imx8qm_ldb_runtime_resume, NULL)
567 };
568 
569 static const struct of_device_id imx8qm_ldb_dt_ids[] = {
570 	{ .compatible = "fsl,imx8qm-ldb" },
571 	{ /* sentinel */ }
572 };
573 MODULE_DEVICE_TABLE(of, imx8qm_ldb_dt_ids);
574 
575 static struct platform_driver imx8qm_ldb_driver = {
576 	.probe	= imx8qm_ldb_probe,
577 	.remove = imx8qm_ldb_remove,
578 	.driver	= {
579 		.pm = pm_ptr(&imx8qm_ldb_pm_ops),
580 		.name = DRIVER_NAME,
581 		.of_match_table = imx8qm_ldb_dt_ids,
582 	},
583 };
584 module_platform_driver(imx8qm_ldb_driver);
585 
586 MODULE_DESCRIPTION("i.MX8QM LVDS Display Bridge(LDB)/Pixel Mapper bridge driver");
587 MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
588 MODULE_LICENSE("GPL v2");
589 MODULE_ALIAS("platform:" DRIVER_NAME);
590