xref: /linux/drivers/gpu/drm/bridge/imx/imx-ldb-helper.c (revision 0791faebfe750292a8a842b64795a390ca4a3b51)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2012 Sascha Hauer, Pengutronix
4  * Copyright 2019,2020,2022 NXP
5  */
6 
7 #include <linux/export.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/regmap.h>
13 
14 #include <drm/drm_bridge.h>
15 #include <drm/drm_of.h>
16 #include <drm/drm_print.h>
17 
18 #include "imx-ldb-helper.h"
19 
20 bool ldb_channel_is_single_link(struct ldb_channel *ldb_ch)
21 {
22 	return ldb_ch->link_type == LDB_CH_SINGLE_LINK;
23 }
24 EXPORT_SYMBOL_GPL(ldb_channel_is_single_link);
25 
26 bool ldb_channel_is_split_link(struct ldb_channel *ldb_ch)
27 {
28 	return ldb_ch->link_type == LDB_CH_DUAL_LINK_EVEN_ODD_PIXELS ||
29 	       ldb_ch->link_type == LDB_CH_DUAL_LINK_ODD_EVEN_PIXELS;
30 }
31 EXPORT_SYMBOL_GPL(ldb_channel_is_split_link);
32 
33 int ldb_bridge_atomic_check_helper(struct drm_bridge *bridge,
34 				   struct drm_bridge_state *bridge_state,
35 				   struct drm_crtc_state *crtc_state,
36 				   struct drm_connector_state *conn_state)
37 {
38 	struct ldb_channel *ldb_ch = bridge->driver_private;
39 
40 	ldb_ch->in_bus_format = bridge_state->input_bus_cfg.format;
41 	ldb_ch->out_bus_format = bridge_state->output_bus_cfg.format;
42 
43 	return 0;
44 }
45 EXPORT_SYMBOL_GPL(ldb_bridge_atomic_check_helper);
46 
47 void ldb_bridge_mode_set_helper(struct drm_bridge *bridge,
48 				const struct drm_display_mode *mode,
49 				const struct drm_display_mode *adjusted_mode)
50 {
51 	struct ldb_channel *ldb_ch = bridge->driver_private;
52 	struct ldb *ldb = ldb_ch->ldb;
53 	bool is_split = ldb_channel_is_split_link(ldb_ch);
54 
55 	if (is_split)
56 		ldb->ldb_ctrl |= LDB_SPLIT_MODE_EN;
57 
58 	switch (ldb_ch->out_bus_format) {
59 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
60 		break;
61 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
62 		if (ldb_ch->chno == 0 || is_split)
63 			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24;
64 		if (ldb_ch->chno == 1 || is_split)
65 			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24;
66 		break;
67 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
68 		if (ldb_ch->chno == 0 || is_split)
69 			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH0_24 |
70 					 LDB_BIT_MAP_CH0_JEIDA;
71 		if (ldb_ch->chno == 1 || is_split)
72 			ldb->ldb_ctrl |= LDB_DATA_WIDTH_CH1_24 |
73 					 LDB_BIT_MAP_CH1_JEIDA;
74 		break;
75 	}
76 }
77 EXPORT_SYMBOL_GPL(ldb_bridge_mode_set_helper);
78 
79 void ldb_bridge_enable_helper(struct drm_bridge *bridge)
80 {
81 	struct ldb_channel *ldb_ch = bridge->driver_private;
82 	struct ldb *ldb = ldb_ch->ldb;
83 
84 	/*
85 	 * Platform specific bridge drivers should set ldb_ctrl properly
86 	 * for the enablement, so just write the ctrl_reg here.
87 	 */
88 	regmap_write(ldb->regmap, ldb->ctrl_reg, ldb->ldb_ctrl);
89 }
90 EXPORT_SYMBOL_GPL(ldb_bridge_enable_helper);
91 
92 void ldb_bridge_disable_helper(struct drm_bridge *bridge)
93 {
94 	struct ldb_channel *ldb_ch = bridge->driver_private;
95 	struct ldb *ldb = ldb_ch->ldb;
96 	bool is_split = ldb_channel_is_split_link(ldb_ch);
97 
98 	if (ldb_ch->chno == 0 || is_split)
99 		ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
100 	if (ldb_ch->chno == 1 || is_split)
101 		ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
102 
103 	regmap_write(ldb->regmap, ldb->ctrl_reg, ldb->ldb_ctrl);
104 }
105 EXPORT_SYMBOL_GPL(ldb_bridge_disable_helper);
106 
107 int ldb_bridge_attach_helper(struct drm_bridge *bridge,
108 			     enum drm_bridge_attach_flags flags)
109 {
110 	struct ldb_channel *ldb_ch = bridge->driver_private;
111 	struct ldb *ldb = ldb_ch->ldb;
112 
113 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
114 		DRM_DEV_ERROR(ldb->dev,
115 			      "do not support creating a drm_connector\n");
116 		return -EINVAL;
117 	}
118 
119 	if (!bridge->encoder) {
120 		DRM_DEV_ERROR(ldb->dev, "missing encoder\n");
121 		return -ENODEV;
122 	}
123 
124 	return drm_bridge_attach(bridge->encoder,
125 				ldb_ch->next_bridge, bridge,
126 				DRM_BRIDGE_ATTACH_NO_CONNECTOR);
127 }
128 EXPORT_SYMBOL_GPL(ldb_bridge_attach_helper);
129 
130 int ldb_init_helper(struct ldb *ldb)
131 {
132 	struct device *dev = ldb->dev;
133 	struct device_node *np = dev->of_node;
134 	struct device_node *child;
135 	int ret;
136 	u32 i;
137 
138 	ldb->regmap = syscon_node_to_regmap(np->parent);
139 	if (IS_ERR(ldb->regmap)) {
140 		ret = PTR_ERR(ldb->regmap);
141 		if (ret != -EPROBE_DEFER)
142 			DRM_DEV_ERROR(dev, "failed to get regmap: %d\n", ret);
143 		return ret;
144 	}
145 
146 	for_each_available_child_of_node(np, child) {
147 		struct ldb_channel *ldb_ch;
148 
149 		ret = of_property_read_u32(child, "reg", &i);
150 		if (ret || i > MAX_LDB_CHAN_NUM - 1) {
151 			ret = -EINVAL;
152 			DRM_DEV_ERROR(dev,
153 				      "invalid channel node address: %u\n", i);
154 			of_node_put(child);
155 			return ret;
156 		}
157 
158 		ldb_ch = ldb->channel[i];
159 		ldb_ch->ldb = ldb;
160 		ldb_ch->chno = i;
161 		ldb_ch->is_available = true;
162 		ldb_ch->np = child;
163 
164 		ldb->available_ch_cnt++;
165 	}
166 
167 	return 0;
168 }
169 EXPORT_SYMBOL_GPL(ldb_init_helper);
170 
171 int ldb_find_next_bridge_helper(struct ldb *ldb)
172 {
173 	struct device *dev = ldb->dev;
174 	struct ldb_channel *ldb_ch;
175 	int ret, i;
176 
177 	for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
178 		ldb_ch = ldb->channel[i];
179 
180 		if (!ldb_ch->is_available)
181 			continue;
182 
183 		ldb_ch->next_bridge = devm_drm_of_get_bridge(dev, ldb_ch->np,
184 							     1, 0);
185 		if (IS_ERR(ldb_ch->next_bridge)) {
186 			ret = PTR_ERR(ldb_ch->next_bridge);
187 			if (ret != -EPROBE_DEFER)
188 				DRM_DEV_ERROR(dev,
189 					      "failed to get next bridge: %d\n",
190 					      ret);
191 			return ret;
192 		}
193 	}
194 
195 	return 0;
196 }
197 EXPORT_SYMBOL_GPL(ldb_find_next_bridge_helper);
198 
199 void ldb_add_bridge_helper(struct ldb *ldb,
200 			   const struct drm_bridge_funcs *bridge_funcs)
201 {
202 	struct ldb_channel *ldb_ch;
203 	int i;
204 
205 	for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
206 		ldb_ch = ldb->channel[i];
207 
208 		if (!ldb_ch->is_available)
209 			continue;
210 
211 		ldb_ch->bridge.driver_private = ldb_ch;
212 		ldb_ch->bridge.funcs = bridge_funcs;
213 		ldb_ch->bridge.of_node = ldb_ch->np;
214 
215 		drm_bridge_add(&ldb_ch->bridge);
216 	}
217 }
218 EXPORT_SYMBOL_GPL(ldb_add_bridge_helper);
219 
220 void ldb_remove_bridge_helper(struct ldb *ldb)
221 {
222 	struct ldb_channel *ldb_ch;
223 	int i;
224 
225 	for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
226 		ldb_ch = ldb->channel[i];
227 
228 		if (!ldb_ch->is_available)
229 			continue;
230 
231 		drm_bridge_remove(&ldb_ch->bridge);
232 	}
233 }
234 EXPORT_SYMBOL_GPL(ldb_remove_bridge_helper);
235 
236 MODULE_DESCRIPTION("i.MX8 LVDS Display Bridge(LDB)/Pixel Mapper bridge helper");
237 MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
238 MODULE_LICENSE("GPL");
239