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11#include <linux/backlight.h>
12#include <linux/gpio/consumer.h>
13#include <linux/module.h>
14#include <linux/of_platform.h>
15#include <linux/platform_device.h>
16#include <linux/regulator/consumer.h>
17#include <linux/slab.h>
18
19#include <video/display_timing.h>
20#include <video/of_display_timing.h>
21#include <video/videomode.h>
22
23#include <drm/drm_crtc.h>
24#include <drm/drm_panel.h>
25
26struct panel_lvds {
27 struct drm_panel panel;
28 struct device *dev;
29
30 const char *label;
31 unsigned int width;
32 unsigned int height;
33 struct videomode video_mode;
34 unsigned int bus_format;
35 bool data_mirror;
36
37 struct backlight_device *backlight;
38 struct regulator *supply;
39
40 struct gpio_desc *enable_gpio;
41 struct gpio_desc *reset_gpio;
42};
43
44static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel)
45{
46 return container_of(panel, struct panel_lvds, panel);
47}
48
49static int panel_lvds_disable(struct drm_panel *panel)
50{
51 struct panel_lvds *lvds = to_panel_lvds(panel);
52
53 if (lvds->backlight) {
54 lvds->backlight->props.power = FB_BLANK_POWERDOWN;
55 lvds->backlight->props.state |= BL_CORE_FBBLANK;
56 backlight_update_status(lvds->backlight);
57 }
58
59 return 0;
60}
61
62static int panel_lvds_unprepare(struct drm_panel *panel)
63{
64 struct panel_lvds *lvds = to_panel_lvds(panel);
65
66 if (lvds->enable_gpio)
67 gpiod_set_value_cansleep(lvds->enable_gpio, 0);
68
69 if (lvds->supply)
70 regulator_disable(lvds->supply);
71
72 return 0;
73}
74
75static int panel_lvds_prepare(struct drm_panel *panel)
76{
77 struct panel_lvds *lvds = to_panel_lvds(panel);
78
79 if (lvds->supply) {
80 int err;
81
82 err = regulator_enable(lvds->supply);
83 if (err < 0) {
84 dev_err(lvds->dev, "failed to enable supply: %d\n",
85 err);
86 return err;
87 }
88 }
89
90 if (lvds->enable_gpio)
91 gpiod_set_value_cansleep(lvds->enable_gpio, 1);
92
93 return 0;
94}
95
96static int panel_lvds_enable(struct drm_panel *panel)
97{
98 struct panel_lvds *lvds = to_panel_lvds(panel);
99
100 if (lvds->backlight) {
101 lvds->backlight->props.state &= ~BL_CORE_FBBLANK;
102 lvds->backlight->props.power = FB_BLANK_UNBLANK;
103 backlight_update_status(lvds->backlight);
104 }
105
106 return 0;
107}
108
109static int panel_lvds_get_modes(struct drm_panel *panel)
110{
111 struct panel_lvds *lvds = to_panel_lvds(panel);
112 struct drm_connector *connector = lvds->panel.connector;
113 struct drm_display_mode *mode;
114
115 mode = drm_mode_create(lvds->panel.drm);
116 if (!mode)
117 return 0;
118
119 drm_display_mode_from_videomode(&lvds->video_mode, mode);
120 mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
121 drm_mode_probed_add(connector, mode);
122
123 connector->display_info.width_mm = lvds->width;
124 connector->display_info.height_mm = lvds->height;
125 drm_display_info_set_bus_formats(&connector->display_info,
126 &lvds->bus_format, 1);
127 connector->display_info.bus_flags = lvds->data_mirror
128 ? DRM_BUS_FLAG_DATA_LSB_TO_MSB
129 : DRM_BUS_FLAG_DATA_MSB_TO_LSB;
130
131 return 1;
132}
133
134static const struct drm_panel_funcs panel_lvds_funcs = {
135 .disable = panel_lvds_disable,
136 .unprepare = panel_lvds_unprepare,
137 .prepare = panel_lvds_prepare,
138 .enable = panel_lvds_enable,
139 .get_modes = panel_lvds_get_modes,
140};
141
142static int panel_lvds_parse_dt(struct panel_lvds *lvds)
143{
144 struct device_node *np = lvds->dev->of_node;
145 struct display_timing timing;
146 const char *mapping;
147 int ret;
148
149 ret = of_get_display_timing(np, "panel-timing", &timing);
150 if (ret < 0)
151 return ret;
152
153 videomode_from_timing(&timing, &lvds->video_mode);
154
155 ret = of_property_read_u32(np, "width-mm", &lvds->width);
156 if (ret < 0) {
157 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
158 np, "width-mm");
159 return -ENODEV;
160 }
161 ret = of_property_read_u32(np, "height-mm", &lvds->height);
162 if (ret < 0) {
163 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
164 np, "height-mm");
165 return -ENODEV;
166 }
167
168 of_property_read_string(np, "label", &lvds->label);
169
170 ret = of_property_read_string(np, "data-mapping", &mapping);
171 if (ret < 0) {
172 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
173 np, "data-mapping");
174 return -ENODEV;
175 }
176
177 if (!strcmp(mapping, "jeida-18")) {
178 lvds->bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG;
179 } else if (!strcmp(mapping, "jeida-24")) {
180 lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA;
181 } else if (!strcmp(mapping, "vesa-24")) {
182 lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG;
183 } else {
184 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
185 np, "data-mapping");
186 return -EINVAL;
187 }
188
189 lvds->data_mirror = of_property_read_bool(np, "data-mirror");
190
191 return 0;
192}
193
194static int panel_lvds_probe(struct platform_device *pdev)
195{
196 struct panel_lvds *lvds;
197 struct device_node *np;
198 int ret;
199
200 lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
201 if (!lvds)
202 return -ENOMEM;
203
204 lvds->dev = &pdev->dev;
205
206 ret = panel_lvds_parse_dt(lvds);
207 if (ret < 0)
208 return ret;
209
210 lvds->supply = devm_regulator_get_optional(lvds->dev, "power");
211 if (IS_ERR(lvds->supply)) {
212 ret = PTR_ERR(lvds->supply);
213
214 if (ret != -ENODEV) {
215 if (ret != -EPROBE_DEFER)
216 dev_err(lvds->dev, "failed to request regulator: %d\n",
217 ret);
218 return ret;
219 }
220
221 lvds->supply = NULL;
222 }
223
224
225 lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable",
226 GPIOD_OUT_LOW);
227 if (IS_ERR(lvds->enable_gpio)) {
228 ret = PTR_ERR(lvds->enable_gpio);
229 dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
230 "enable", ret);
231 return ret;
232 }
233
234 lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset",
235 GPIOD_OUT_HIGH);
236 if (IS_ERR(lvds->reset_gpio)) {
237 ret = PTR_ERR(lvds->reset_gpio);
238 dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
239 "reset", ret);
240 return ret;
241 }
242
243 np = of_parse_phandle(lvds->dev->of_node, "backlight", 0);
244 if (np) {
245 lvds->backlight = of_find_backlight_by_node(np);
246 of_node_put(np);
247
248 if (!lvds->backlight)
249 return -EPROBE_DEFER;
250 }
251
252
253
254
255
256
257
258
259
260 drm_panel_init(&lvds->panel);
261 lvds->panel.dev = lvds->dev;
262 lvds->panel.funcs = &panel_lvds_funcs;
263
264 ret = drm_panel_add(&lvds->panel);
265 if (ret < 0)
266 goto error;
267
268 dev_set_drvdata(lvds->dev, lvds);
269 return 0;
270
271error:
272 put_device(&lvds->backlight->dev);
273 return ret;
274}
275
276static int panel_lvds_remove(struct platform_device *pdev)
277{
278 struct panel_lvds *lvds = dev_get_drvdata(&pdev->dev);
279
280 drm_panel_remove(&lvds->panel);
281
282 panel_lvds_disable(&lvds->panel);
283
284 if (lvds->backlight)
285 put_device(&lvds->backlight->dev);
286
287 return 0;
288}
289
290static const struct of_device_id panel_lvds_of_table[] = {
291 { .compatible = "panel-lvds", },
292 { },
293};
294
295MODULE_DEVICE_TABLE(of, panel_lvds_of_table);
296
297static struct platform_driver panel_lvds_driver = {
298 .probe = panel_lvds_probe,
299 .remove = panel_lvds_remove,
300 .driver = {
301 .name = "panel-lvds",
302 .of_match_table = panel_lvds_of_table,
303 },
304};
305
306module_platform_driver(panel_lvds_driver);
307
308MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
309MODULE_DESCRIPTION("LVDS Panel Driver");
310MODULE_LICENSE("GPL");
311