summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/panel/panel-lvds.c
blob: 5ce3f4a2b7a19da6849b41fdb697c8d71025a3db (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
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
// SPDX-License-Identifier: GPL-2.0+
/*
 * Generic LVDS panel driver
 *
 * Copyright (C) 2016 Laurent Pinchart
 * Copyright (C) 2016 Renesas Electronics Corporation
 *
 * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
 */

#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>

#include <video/display_timing.h>
#include <video/of_display_timing.h>
#include <video/videomode.h>

#include <drm/drm_crtc.h>
#include <drm/drm_panel.h>

struct panel_lvds {
	struct drm_panel panel;
	struct device *dev;

	const char *label;
	unsigned int width;
	unsigned int height;
	struct videomode video_mode;
	unsigned int bus_format;
	bool data_mirror;

	struct regulator *supply;

	struct gpio_desc *enable_gpio;
	struct gpio_desc *reset_gpio;
};

static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel)
{
	return container_of(panel, struct panel_lvds, panel);
}

static int panel_lvds_unprepare(struct drm_panel *panel)
{
	struct panel_lvds *lvds = to_panel_lvds(panel);

	if (lvds->enable_gpio)
		gpiod_set_value_cansleep(lvds->enable_gpio, 0);

	if (lvds->supply)
		regulator_disable(lvds->supply);

	return 0;
}

static int panel_lvds_prepare(struct drm_panel *panel)
{
	struct panel_lvds *lvds = to_panel_lvds(panel);

	if (lvds->supply) {
		int err;

		err = regulator_enable(lvds->supply);
		if (err < 0) {
			dev_err(lvds->dev, "failed to enable supply: %d\n",
				err);
			return err;
		}
	}

	if (lvds->enable_gpio)
		gpiod_set_value_cansleep(lvds->enable_gpio, 1);

	return 0;
}

static int panel_lvds_get_modes(struct drm_panel *panel,
				struct drm_connector *connector)
{
	struct panel_lvds *lvds = to_panel_lvds(panel);
	struct drm_display_mode *mode;

	mode = drm_mode_create(connector->dev);
	if (!mode)
		return 0;

	drm_display_mode_from_videomode(&lvds->video_mode, mode);
	mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
	drm_mode_probed_add(connector, mode);

	connector->display_info.width_mm = lvds->width;
	connector->display_info.height_mm = lvds->height;
	drm_display_info_set_bus_formats(&connector->display_info,
					 &lvds->bus_format, 1);
	connector->display_info.bus_flags = lvds->data_mirror
					  ? DRM_BUS_FLAG_DATA_LSB_TO_MSB
					  : DRM_BUS_FLAG_DATA_MSB_TO_LSB;

	return 1;
}

static const struct drm_panel_funcs panel_lvds_funcs = {
	.unprepare = panel_lvds_unprepare,
	.prepare = panel_lvds_prepare,
	.get_modes = panel_lvds_get_modes,
};

static int panel_lvds_parse_dt(struct panel_lvds *lvds)
{
	struct device_node *np = lvds->dev->of_node;
	struct display_timing timing;
	const char *mapping;
	int ret;

	ret = of_get_display_timing(np, "panel-timing", &timing);
	if (ret < 0) {
		dev_err(lvds->dev, "%pOF: problems parsing panel-timing (%d)\n",
			np, ret);
		return ret;
	}

	videomode_from_timing(&timing, &lvds->video_mode);

	ret = of_property_read_u32(np, "width-mm", &lvds->width);
	if (ret < 0) {
		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
			np, "width-mm");
		return -ENODEV;
	}
	ret = of_property_read_u32(np, "height-mm", &lvds->height);
	if (ret < 0) {
		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
			np, "height-mm");
		return -ENODEV;
	}

	of_property_read_string(np, "label", &lvds->label);

	ret = of_property_read_string(np, "data-mapping", &mapping);
	if (ret < 0) {
		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
			np, "data-mapping");
		return -ENODEV;
	}

	if (!strcmp(mapping, "jeida-18")) {
		lvds->bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG;
	} else if (!strcmp(mapping, "jeida-24")) {
		lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA;
	} else if (!strcmp(mapping, "vesa-24")) {
		lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG;
	} else {
		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
			np, "data-mapping");
		return -EINVAL;
	}

	lvds->data_mirror = of_property_read_bool(np, "data-mirror");

	return 0;
}

static int panel_lvds_probe(struct platform_device *pdev)
{
	struct panel_lvds *lvds;
	int ret;

	lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
	if (!lvds)
		return -ENOMEM;

	lvds->dev = &pdev->dev;

	ret = panel_lvds_parse_dt(lvds);
	if (ret < 0)
		return ret;

	lvds->supply = devm_regulator_get_optional(lvds->dev, "power");
	if (IS_ERR(lvds->supply)) {
		ret = PTR_ERR(lvds->supply);

		if (ret != -ENODEV) {
			if (ret != -EPROBE_DEFER)
				dev_err(lvds->dev, "failed to request regulator: %d\n",
					ret);
			return ret;
		}

		lvds->supply = NULL;
	}

	/* Get GPIOs and backlight controller. */
	lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable",
						     GPIOD_OUT_LOW);
	if (IS_ERR(lvds->enable_gpio)) {
		ret = PTR_ERR(lvds->enable_gpio);
		dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
			"enable", ret);
		return ret;
	}

	lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset",
						     GPIOD_OUT_HIGH);
	if (IS_ERR(lvds->reset_gpio)) {
		ret = PTR_ERR(lvds->reset_gpio);
		dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
			"reset", ret);
		return ret;
	}

	/*
	 * TODO: Handle all power supplies specified in the DT node in a generic
	 * way for panels that don't care about power supply ordering. LVDS
	 * panels that require a specific power sequence will need a dedicated
	 * driver.
	 */

	/* Register the panel. */
	drm_panel_init(&lvds->panel, lvds->dev, &panel_lvds_funcs,
		       DRM_MODE_CONNECTOR_LVDS);

	ret = drm_panel_of_backlight(&lvds->panel);
	if (ret)
		return ret;

	ret = drm_panel_add(&lvds->panel);
	if (ret < 0)
		return ret;

	dev_set_drvdata(lvds->dev, lvds);
	return 0;
}

static int panel_lvds_remove(struct platform_device *pdev)
{
	struct panel_lvds *lvds = dev_get_drvdata(&pdev->dev);

	drm_panel_remove(&lvds->panel);

	drm_panel_disable(&lvds->panel);

	return 0;
}

static const struct of_device_id panel_lvds_of_table[] = {
	{ .compatible = "panel-lvds", },
	{ /* Sentinel */ },
};

MODULE_DEVICE_TABLE(of, panel_lvds_of_table);

static struct platform_driver panel_lvds_driver = {
	.probe		= panel_lvds_probe,
	.remove		= panel_lvds_remove,
	.driver		= {
		.name	= "panel-lvds",
		.of_match_table = panel_lvds_of_table,
	},
};

module_platform_driver(panel_lvds_driver);

MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
MODULE_DESCRIPTION("LVDS Panel Driver");
MODULE_LICENSE("GPL");