1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 NVIDIA Corporation
4  */
5 
6 #include <linux/delay.h>
7 #include <linux/gpio/consumer.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/regulator/consumer.h>
11 
12 #include <video/mipi_display.h>
13 
14 #include <drm/drm_crtc.h>
15 #include <drm/drm_device.h>
16 #include <drm/drm_mipi_dsi.h>
17 #include <drm/drm_panel.h>
18 
19 struct sharp_panel {
20 	struct drm_panel base;
21 	/* the datasheet refers to them as DSI-LINK1 and DSI-LINK2 */
22 	struct mipi_dsi_device *link1;
23 	struct mipi_dsi_device *link2;
24 
25 	struct regulator *supply;
26 
27 	bool prepared;
28 	bool enabled;
29 
30 	const struct drm_display_mode *mode;
31 };
32 
to_sharp_panel(struct drm_panel * panel)33 static inline struct sharp_panel *to_sharp_panel(struct drm_panel *panel)
34 {
35 	return container_of(panel, struct sharp_panel, base);
36 }
37 
sharp_wait_frames(struct sharp_panel * sharp,unsigned int frames)38 static void sharp_wait_frames(struct sharp_panel *sharp, unsigned int frames)
39 {
40 	unsigned int refresh = drm_mode_vrefresh(sharp->mode);
41 
42 	if (WARN_ON(frames > refresh))
43 		return;
44 
45 	msleep(1000 / (refresh / frames));
46 }
47 
sharp_panel_write(struct sharp_panel * sharp,u16 offset,u8 value)48 static int sharp_panel_write(struct sharp_panel *sharp, u16 offset, u8 value)
49 {
50 	u8 payload[3] = { offset >> 8, offset & 0xff, value };
51 	struct mipi_dsi_device *dsi = sharp->link1;
52 	ssize_t err;
53 
54 	err = mipi_dsi_generic_write(dsi, payload, sizeof(payload));
55 	if (err < 0) {
56 		dev_err(&dsi->dev, "failed to write %02x to %04x: %zd\n",
57 			value, offset, err);
58 		return err;
59 	}
60 
61 	err = mipi_dsi_dcs_nop(dsi);
62 	if (err < 0) {
63 		dev_err(&dsi->dev, "failed to send DCS nop: %zd\n", err);
64 		return err;
65 	}
66 
67 	usleep_range(10, 20);
68 
69 	return 0;
70 }
71 
sharp_panel_read(struct sharp_panel * sharp,u16 offset,u8 * value)72 static __maybe_unused int sharp_panel_read(struct sharp_panel *sharp,
73 					   u16 offset, u8 *value)
74 {
75 	ssize_t err;
76 
77 	cpu_to_be16s(&offset);
78 
79 	err = mipi_dsi_generic_read(sharp->link1, &offset, sizeof(offset),
80 				    value, sizeof(*value));
81 	if (err < 0)
82 		dev_err(&sharp->link1->dev, "failed to read from %04x: %zd\n",
83 			offset, err);
84 
85 	return err;
86 }
87 
sharp_panel_disable(struct drm_panel * panel)88 static int sharp_panel_disable(struct drm_panel *panel)
89 {
90 	struct sharp_panel *sharp = to_sharp_panel(panel);
91 
92 	if (!sharp->enabled)
93 		return 0;
94 
95 	sharp->enabled = false;
96 
97 	return 0;
98 }
99 
sharp_panel_unprepare(struct drm_panel * panel)100 static int sharp_panel_unprepare(struct drm_panel *panel)
101 {
102 	struct sharp_panel *sharp = to_sharp_panel(panel);
103 	int err;
104 
105 	if (!sharp->prepared)
106 		return 0;
107 
108 	sharp_wait_frames(sharp, 4);
109 
110 	err = mipi_dsi_dcs_set_display_off(sharp->link1);
111 	if (err < 0)
112 		dev_err(panel->dev, "failed to set display off: %d\n", err);
113 
114 	err = mipi_dsi_dcs_enter_sleep_mode(sharp->link1);
115 	if (err < 0)
116 		dev_err(panel->dev, "failed to enter sleep mode: %d\n", err);
117 
118 	msleep(120);
119 
120 	regulator_disable(sharp->supply);
121 
122 	sharp->prepared = false;
123 
124 	return 0;
125 }
126 
sharp_setup_symmetrical_split(struct mipi_dsi_device * left,struct mipi_dsi_device * right,const struct drm_display_mode * mode)127 static int sharp_setup_symmetrical_split(struct mipi_dsi_device *left,
128 					 struct mipi_dsi_device *right,
129 					 const struct drm_display_mode *mode)
130 {
131 	int err;
132 
133 	err = mipi_dsi_dcs_set_column_address(left, 0, mode->hdisplay / 2 - 1);
134 	if (err < 0) {
135 		dev_err(&left->dev, "failed to set column address: %d\n", err);
136 		return err;
137 	}
138 
139 	err = mipi_dsi_dcs_set_page_address(left, 0, mode->vdisplay - 1);
140 	if (err < 0) {
141 		dev_err(&left->dev, "failed to set page address: %d\n", err);
142 		return err;
143 	}
144 
145 	err = mipi_dsi_dcs_set_column_address(right, mode->hdisplay / 2,
146 					      mode->hdisplay - 1);
147 	if (err < 0) {
148 		dev_err(&right->dev, "failed to set column address: %d\n", err);
149 		return err;
150 	}
151 
152 	err = mipi_dsi_dcs_set_page_address(right, 0, mode->vdisplay - 1);
153 	if (err < 0) {
154 		dev_err(&right->dev, "failed to set page address: %d\n", err);
155 		return err;
156 	}
157 
158 	return 0;
159 }
160 
sharp_panel_prepare(struct drm_panel * panel)161 static int sharp_panel_prepare(struct drm_panel *panel)
162 {
163 	struct sharp_panel *sharp = to_sharp_panel(panel);
164 	u8 format = MIPI_DCS_PIXEL_FMT_24BIT;
165 	int err;
166 
167 	if (sharp->prepared)
168 		return 0;
169 
170 	err = regulator_enable(sharp->supply);
171 	if (err < 0)
172 		return err;
173 
174 	/*
175 	 * According to the datasheet, the panel needs around 10 ms to fully
176 	 * power up. At least another 120 ms is required before exiting sleep
177 	 * mode to make sure the panel is ready. Throw in another 20 ms for
178 	 * good measure.
179 	 */
180 	msleep(150);
181 
182 	err = mipi_dsi_dcs_exit_sleep_mode(sharp->link1);
183 	if (err < 0) {
184 		dev_err(panel->dev, "failed to exit sleep mode: %d\n", err);
185 		goto poweroff;
186 	}
187 
188 	/*
189 	 * The MIPI DCS specification mandates this delay only between the
190 	 * exit_sleep_mode and enter_sleep_mode commands, so it isn't strictly
191 	 * necessary here.
192 	 */
193 	/*
194 	msleep(120);
195 	*/
196 
197 	/* set left-right mode */
198 	err = sharp_panel_write(sharp, 0x1000, 0x2a);
199 	if (err < 0) {
200 		dev_err(panel->dev, "failed to set left-right mode: %d\n", err);
201 		goto poweroff;
202 	}
203 
204 	/* enable command mode */
205 	err = sharp_panel_write(sharp, 0x1001, 0x01);
206 	if (err < 0) {
207 		dev_err(panel->dev, "failed to enable command mode: %d\n", err);
208 		goto poweroff;
209 	}
210 
211 	err = mipi_dsi_dcs_set_pixel_format(sharp->link1, format);
212 	if (err < 0) {
213 		dev_err(panel->dev, "failed to set pixel format: %d\n", err);
214 		goto poweroff;
215 	}
216 
217 	/*
218 	 * TODO: The device supports both left-right and even-odd split
219 	 * configurations, but this driver currently supports only the left-
220 	 * right split. To support a different mode a mechanism needs to be
221 	 * put in place to communicate the configuration back to the DSI host
222 	 * controller.
223 	 */
224 	err = sharp_setup_symmetrical_split(sharp->link1, sharp->link2,
225 					    sharp->mode);
226 	if (err < 0) {
227 		dev_err(panel->dev, "failed to set up symmetrical split: %d\n",
228 			err);
229 		goto poweroff;
230 	}
231 
232 	err = mipi_dsi_dcs_set_display_on(sharp->link1);
233 	if (err < 0) {
234 		dev_err(panel->dev, "failed to set display on: %d\n", err);
235 		goto poweroff;
236 	}
237 
238 	sharp->prepared = true;
239 
240 	/* wait for 6 frames before continuing */
241 	sharp_wait_frames(sharp, 6);
242 
243 	return 0;
244 
245 poweroff:
246 	regulator_disable(sharp->supply);
247 	return err;
248 }
249 
sharp_panel_enable(struct drm_panel * panel)250 static int sharp_panel_enable(struct drm_panel *panel)
251 {
252 	struct sharp_panel *sharp = to_sharp_panel(panel);
253 
254 	if (sharp->enabled)
255 		return 0;
256 
257 	sharp->enabled = true;
258 
259 	return 0;
260 }
261 
262 static const struct drm_display_mode default_mode = {
263 	.clock = 278000,
264 	.hdisplay = 2560,
265 	.hsync_start = 2560 + 128,
266 	.hsync_end = 2560 + 128 + 64,
267 	.htotal = 2560 + 128 + 64 + 64,
268 	.vdisplay = 1600,
269 	.vsync_start = 1600 + 4,
270 	.vsync_end = 1600 + 4 + 8,
271 	.vtotal = 1600 + 4 + 8 + 32,
272 };
273 
sharp_panel_get_modes(struct drm_panel * panel,struct drm_connector * connector)274 static int sharp_panel_get_modes(struct drm_panel *panel,
275 				 struct drm_connector *connector)
276 {
277 	struct drm_display_mode *mode;
278 
279 	mode = drm_mode_duplicate(connector->dev, &default_mode);
280 	if (!mode) {
281 		dev_err(panel->dev, "failed to add mode %ux%ux@%u\n",
282 			default_mode.hdisplay, default_mode.vdisplay,
283 			drm_mode_vrefresh(&default_mode));
284 		return -ENOMEM;
285 	}
286 
287 	drm_mode_set_name(mode);
288 
289 	drm_mode_probed_add(connector, mode);
290 
291 	connector->display_info.width_mm = 217;
292 	connector->display_info.height_mm = 136;
293 
294 	return 1;
295 }
296 
297 static const struct drm_panel_funcs sharp_panel_funcs = {
298 	.disable = sharp_panel_disable,
299 	.unprepare = sharp_panel_unprepare,
300 	.prepare = sharp_panel_prepare,
301 	.enable = sharp_panel_enable,
302 	.get_modes = sharp_panel_get_modes,
303 };
304 
305 static const struct of_device_id sharp_of_match[] = {
306 	{ .compatible = "sharp,lq101r1sx01", },
307 	{ }
308 };
309 MODULE_DEVICE_TABLE(of, sharp_of_match);
310 
sharp_panel_add(struct sharp_panel * sharp)311 static int sharp_panel_add(struct sharp_panel *sharp)
312 {
313 	int ret;
314 
315 	sharp->mode = &default_mode;
316 
317 	sharp->supply = devm_regulator_get(&sharp->link1->dev, "power");
318 	if (IS_ERR(sharp->supply))
319 		return PTR_ERR(sharp->supply);
320 
321 	drm_panel_init(&sharp->base, &sharp->link1->dev, &sharp_panel_funcs,
322 		       DRM_MODE_CONNECTOR_DSI);
323 
324 	ret = drm_panel_of_backlight(&sharp->base);
325 	if (ret)
326 		return ret;
327 
328 	drm_panel_add(&sharp->base);
329 
330 	return 0;
331 }
332 
sharp_panel_del(struct sharp_panel * sharp)333 static void sharp_panel_del(struct sharp_panel *sharp)
334 {
335 	if (sharp->base.dev)
336 		drm_panel_remove(&sharp->base);
337 
338 	if (sharp->link2)
339 		put_device(&sharp->link2->dev);
340 }
341 
sharp_panel_probe(struct mipi_dsi_device * dsi)342 static int sharp_panel_probe(struct mipi_dsi_device *dsi)
343 {
344 	struct mipi_dsi_device *secondary = NULL;
345 	struct sharp_panel *sharp;
346 	struct device_node *np;
347 	int err;
348 
349 	dsi->lanes = 4;
350 	dsi->format = MIPI_DSI_FMT_RGB888;
351 	dsi->mode_flags = MIPI_DSI_MODE_LPM;
352 
353 	/* Find DSI-LINK1 */
354 	np = of_parse_phandle(dsi->dev.of_node, "link2", 0);
355 	if (np) {
356 		secondary = of_find_mipi_dsi_device_by_node(np);
357 		of_node_put(np);
358 
359 		if (!secondary)
360 			return -EPROBE_DEFER;
361 	}
362 
363 	/* register a panel for only the DSI-LINK1 interface */
364 	if (secondary) {
365 		sharp = devm_kzalloc(&dsi->dev, sizeof(*sharp), GFP_KERNEL);
366 		if (!sharp) {
367 			put_device(&secondary->dev);
368 			return -ENOMEM;
369 		}
370 
371 		mipi_dsi_set_drvdata(dsi, sharp);
372 
373 		sharp->link2 = secondary;
374 		sharp->link1 = dsi;
375 
376 		err = sharp_panel_add(sharp);
377 		if (err < 0) {
378 			put_device(&secondary->dev);
379 			return err;
380 		}
381 	}
382 
383 	err = mipi_dsi_attach(dsi);
384 	if (err < 0) {
385 		if (secondary)
386 			sharp_panel_del(sharp);
387 
388 		return err;
389 	}
390 
391 	return 0;
392 }
393 
sharp_panel_remove(struct mipi_dsi_device * dsi)394 static void sharp_panel_remove(struct mipi_dsi_device *dsi)
395 {
396 	struct sharp_panel *sharp = mipi_dsi_get_drvdata(dsi);
397 	int err;
398 
399 	/* only detach from host for the DSI-LINK2 interface */
400 	if (!sharp) {
401 		mipi_dsi_detach(dsi);
402 		return;
403 	}
404 
405 	err = drm_panel_disable(&sharp->base);
406 	if (err < 0)
407 		dev_err(&dsi->dev, "failed to disable panel: %d\n", err);
408 
409 	err = mipi_dsi_detach(dsi);
410 	if (err < 0)
411 		dev_err(&dsi->dev, "failed to detach from DSI host: %d\n", err);
412 
413 	sharp_panel_del(sharp);
414 }
415 
sharp_panel_shutdown(struct mipi_dsi_device * dsi)416 static void sharp_panel_shutdown(struct mipi_dsi_device *dsi)
417 {
418 	struct sharp_panel *sharp = mipi_dsi_get_drvdata(dsi);
419 
420 	/* nothing to do for DSI-LINK2 */
421 	if (!sharp)
422 		return;
423 
424 	drm_panel_disable(&sharp->base);
425 }
426 
427 static struct mipi_dsi_driver sharp_panel_driver = {
428 	.driver = {
429 		.name = "panel-sharp-lq101r1sx01",
430 		.of_match_table = sharp_of_match,
431 	},
432 	.probe = sharp_panel_probe,
433 	.remove = sharp_panel_remove,
434 	.shutdown = sharp_panel_shutdown,
435 };
436 module_mipi_dsi_driver(sharp_panel_driver);
437 
438 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
439 MODULE_DESCRIPTION("Sharp LQ101R1SX01 panel driver");
440 MODULE_LICENSE("GPL v2");
441