summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/bridge/waveshare-dsi.c
blob: 43f4e7412d722281d66b8776aa726a320bc4f7c8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright 2025 NXP
 * Based on panel-raspberrypi-touchscreen by Broadcom
 */

#include <linux/backlight.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_graph.h>
#include <linux/regmap.h>

#include <drm/drm_bridge.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_of.h>
#include <drm/drm_panel.h>

struct ws_bridge {
	struct drm_bridge bridge;
	struct drm_bridge *next_bridge;
	struct backlight_device *backlight;
	struct device *dev;
	struct regmap *reg_map;
};

static const struct regmap_config ws_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = 0xff,
};

static struct ws_bridge *bridge_to_ws_bridge(struct drm_bridge *bridge)
{
	return container_of(bridge, struct ws_bridge, bridge);
}

static int ws_bridge_attach_dsi(struct ws_bridge *ws)
{
	const struct mipi_dsi_device_info info = {
		.type = "ws-bridge",
		.channel = 0,
		.node = NULL,
	};
	struct device_node *dsi_host_node;
	struct device *dev = ws->dev;
	struct mipi_dsi_device *dsi;
	struct mipi_dsi_host *host;
	int ret;

	dsi_host_node = of_graph_get_remote_node(dev->of_node, 0, 0);
	if (!dsi_host_node) {
		dev_err(dev, "Failed to get remote port\n");
		return -ENODEV;
	}
	host = of_find_mipi_dsi_host_by_node(dsi_host_node);
	of_node_put(dsi_host_node);
	if (!host)
		return dev_err_probe(dev, -EPROBE_DEFER, "Failed to find dsi_host\n");

	dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
	if (IS_ERR(dsi))
		return dev_err_probe(dev, PTR_ERR(dsi), "Failed to create dsi device\n");

	dsi->mode_flags = MIPI_DSI_MODE_VIDEO_HSE | MIPI_DSI_MODE_VIDEO |
			  MIPI_DSI_CLOCK_NON_CONTINUOUS;
	dsi->format = MIPI_DSI_FMT_RGB888;
	dsi->lanes = 2;

	ret = devm_mipi_dsi_attach(dev, dsi);
	if (ret < 0)
		return dev_err_probe(dev, ret, "Failed to attach dsi to host\n");

	return 0;
}

static int ws_bridge_bridge_attach(struct drm_bridge *bridge,
				   struct drm_encoder *encoder,
				   enum drm_bridge_attach_flags flags)
{
	struct ws_bridge *ws = bridge_to_ws_bridge(bridge);
	int ret;

	ret = ws_bridge_attach_dsi(ws);
	if (ret)
		return ret;

	return drm_bridge_attach(encoder, ws->next_bridge,
				 &ws->bridge, flags);
}

static void ws_bridge_bridge_enable(struct drm_bridge *bridge)
{
	struct ws_bridge *ws = bridge_to_ws_bridge(bridge);

	regmap_write(ws->reg_map, 0xad, 0x01);
	backlight_enable(ws->backlight);
}

static void ws_bridge_bridge_disable(struct drm_bridge *bridge)
{
	struct ws_bridge *ws = bridge_to_ws_bridge(bridge);

	backlight_disable(ws->backlight);
	regmap_write(ws->reg_map, 0xad, 0x00);
}

static const struct drm_bridge_funcs ws_bridge_bridge_funcs = {
	.enable = ws_bridge_bridge_enable,
	.disable = ws_bridge_bridge_disable,
	.attach = ws_bridge_bridge_attach,
};

static int ws_bridge_bl_update_status(struct backlight_device *bl)
{
	struct ws_bridge *ws = bl_get_data(bl);

	regmap_write(ws->reg_map, 0xab, 0xff - backlight_get_brightness(bl));
	regmap_write(ws->reg_map, 0xaa, 0x01);

	return 0;
}

static const struct backlight_ops ws_bridge_bl_ops = {
	.update_status = ws_bridge_bl_update_status,
};

static struct backlight_device *ws_bridge_create_backlight(struct ws_bridge *ws)
{
	const struct backlight_properties props = {
		.type = BACKLIGHT_RAW,
		.brightness = 255,
		.max_brightness = 255,
	};
	struct device *dev = ws->dev;

	return devm_backlight_device_register(dev, dev_name(dev), dev, ws,
					      &ws_bridge_bl_ops, &props);
}

static int ws_bridge_probe(struct i2c_client *i2c)
{
	struct device *dev = &i2c->dev;
	struct drm_panel *panel;
	struct ws_bridge *ws;
	int ret;

	ws = devm_drm_bridge_alloc(dev, struct ws_bridge, bridge, &ws_bridge_bridge_funcs);
	if (IS_ERR(ws))
		return PTR_ERR(ws);

	ws->dev = dev;

	ws->reg_map = devm_regmap_init_i2c(i2c, &ws_regmap_config);
	if (IS_ERR(ws->reg_map))
		return dev_err_probe(dev, PTR_ERR(ws->reg_map), "Failed to allocate regmap\n");

	ret = drm_of_find_panel_or_bridge(dev->of_node, 1, -1, &panel, NULL);
	if (ret)
		return dev_err_probe(dev, ret, "Failed to find remote panel\n");

	ws->next_bridge = devm_drm_panel_bridge_add(dev, panel);
	if (IS_ERR(ws->next_bridge))
		return PTR_ERR(ws->next_bridge);

	ws->backlight = ws_bridge_create_backlight(ws);
	if (IS_ERR(ws->backlight)) {
		ret = PTR_ERR(ws->backlight);
		dev_err(dev, "Failed to create backlight: %d\n", ret);
		return ret;
	}

	regmap_write(ws->reg_map, 0xc0, 0x01);
	regmap_write(ws->reg_map, 0xc2, 0x01);
	regmap_write(ws->reg_map, 0xac, 0x01);

	ws->bridge.type = DRM_MODE_CONNECTOR_DPI;
	ws->bridge.of_node = dev->of_node;
	devm_drm_bridge_add(dev, &ws->bridge);

	return 0;
}

static const struct of_device_id ws_bridge_of_ids[] = {
	{.compatible = "waveshare,dsi2dpi",},
	{ }
};

MODULE_DEVICE_TABLE(of, ws_bridge_of_ids);

static struct i2c_driver ws_bridge_driver = {
	.driver = {
		.name = "ws_dsi2dpi",
		.of_match_table = ws_bridge_of_ids,
	},
	.probe = ws_bridge_probe,
};
module_i2c_driver(ws_bridge_driver);

MODULE_AUTHOR("Joseph Guo <qijian.guo@nxp.com>");
MODULE_DESCRIPTION("Waveshare DSI2DPI bridge driver");
MODULE_LICENSE("GPL");