1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic DSI Command Mode panel driver
4  *
5  * Copyright (C) 2013 Texas Instruments Incorporated - https://www.ti.com/
6  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
7  */
8 
9 #include <linux/backlight.h>
10 #include <linux/delay.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/jiffies.h>
13 #include <linux/module.h>
14 #include <linux/of_device.h>
15 #include <linux/regulator/consumer.h>
16 
17 #include <drm/drm_connector.h>
18 #include <drm/drm_mipi_dsi.h>
19 #include <drm/drm_modes.h>
20 #include <drm/drm_panel.h>
21 
22 #include <video/mipi_display.h>
23 
24 #define DCS_GET_ID1		0xda
25 #define DCS_GET_ID2		0xdb
26 #define DCS_GET_ID3		0xdc
27 
28 #define DCS_REGULATOR_SUPPLY_NUM 2
29 
30 static const struct of_device_id dsicm_of_match[];
31 
32 struct dsic_panel_data {
33 	u32 xres;
34 	u32 yres;
35 	u32 refresh;
36 	u32 width_mm;
37 	u32 height_mm;
38 	u32 max_hs_rate;
39 	u32 max_lp_rate;
40 	bool te_support;
41 };
42 
43 struct panel_drv_data {
44 	struct mipi_dsi_device *dsi;
45 	struct drm_panel panel;
46 	struct drm_display_mode mode;
47 
48 	struct mutex lock;
49 
50 	struct backlight_device *bldev;
51 	struct backlight_device *extbldev;
52 
53 	unsigned long	hw_guard_end;	/* next value of jiffies when we can
54 					 * issue the next sleep in/out command
55 					 */
56 	unsigned long	hw_guard_wait;	/* max guard time in jiffies */
57 
58 	const struct dsic_panel_data *panel_data;
59 
60 	struct gpio_desc *reset_gpio;
61 
62 	struct regulator_bulk_data supplies[DCS_REGULATOR_SUPPLY_NUM];
63 
64 	bool use_dsi_backlight;
65 
66 	/* runtime variables */
67 	bool enabled;
68 
69 	bool intro_printed;
70 };
71 
72 static inline struct panel_drv_data *panel_to_ddata(struct drm_panel *panel)
73 {
74 	return container_of(panel, struct panel_drv_data, panel);
75 }
76 
77 static void dsicm_bl_power(struct panel_drv_data *ddata, bool enable)
78 {
79 	struct backlight_device *backlight;
80 
81 	if (ddata->bldev)
82 		backlight = ddata->bldev;
83 	else if (ddata->extbldev)
84 		backlight = ddata->extbldev;
85 	else
86 		return;
87 
88 	if (enable) {
89 		backlight->props.fb_blank = FB_BLANK_UNBLANK;
90 		backlight->props.state = ~(BL_CORE_FBBLANK | BL_CORE_SUSPENDED);
91 		backlight->props.power = FB_BLANK_UNBLANK;
92 	} else {
93 		backlight->props.fb_blank = FB_BLANK_NORMAL;
94 		backlight->props.power = FB_BLANK_POWERDOWN;
95 		backlight->props.state |= BL_CORE_FBBLANK | BL_CORE_SUSPENDED;
96 	}
97 
98 	backlight_update_status(backlight);
99 }
100 
101 static void hw_guard_start(struct panel_drv_data *ddata, int guard_msec)
102 {
103 	ddata->hw_guard_wait = msecs_to_jiffies(guard_msec);
104 	ddata->hw_guard_end = jiffies + ddata->hw_guard_wait;
105 }
106 
107 static void hw_guard_wait(struct panel_drv_data *ddata)
108 {
109 	unsigned long wait = ddata->hw_guard_end - jiffies;
110 
111 	if ((long)wait > 0 && wait <= ddata->hw_guard_wait) {
112 		set_current_state(TASK_UNINTERRUPTIBLE);
113 		schedule_timeout(wait);
114 	}
115 }
116 
117 static int dsicm_dcs_read_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 *data)
118 {
119 	return mipi_dsi_dcs_read(ddata->dsi, dcs_cmd, data, 1);
120 }
121 
122 static int dsicm_dcs_write_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 param)
123 {
124 	return mipi_dsi_dcs_write(ddata->dsi, dcs_cmd, &param, 1);
125 }
126 
127 static int dsicm_sleep_in(struct panel_drv_data *ddata)
128 
129 {
130 	int r;
131 
132 	hw_guard_wait(ddata);
133 
134 	r = mipi_dsi_dcs_enter_sleep_mode(ddata->dsi);
135 	if (r)
136 		return r;
137 
138 	hw_guard_start(ddata, 120);
139 
140 	usleep_range(5000, 10000);
141 
142 	return 0;
143 }
144 
145 static int dsicm_sleep_out(struct panel_drv_data *ddata)
146 {
147 	int r;
148 
149 	hw_guard_wait(ddata);
150 
151 	r = mipi_dsi_dcs_exit_sleep_mode(ddata->dsi);
152 	if (r)
153 		return r;
154 
155 	hw_guard_start(ddata, 120);
156 
157 	usleep_range(5000, 10000);
158 
159 	return 0;
160 }
161 
162 static int dsicm_get_id(struct panel_drv_data *ddata, u8 *id1, u8 *id2, u8 *id3)
163 {
164 	int r;
165 
166 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID1, id1);
167 	if (r)
168 		return r;
169 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID2, id2);
170 	if (r)
171 		return r;
172 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID3, id3);
173 	if (r)
174 		return r;
175 
176 	return 0;
177 }
178 
179 static int dsicm_set_update_window(struct panel_drv_data *ddata)
180 {
181 	struct mipi_dsi_device *dsi = ddata->dsi;
182 	int r;
183 
184 	r = mipi_dsi_dcs_set_column_address(dsi, 0, ddata->mode.hdisplay - 1);
185 	if (r < 0)
186 		return r;
187 
188 	r = mipi_dsi_dcs_set_page_address(dsi, 0, ddata->mode.vdisplay - 1);
189 	if (r < 0)
190 		return r;
191 
192 	return 0;
193 }
194 
195 static int dsicm_bl_update_status(struct backlight_device *dev)
196 {
197 	struct panel_drv_data *ddata = dev_get_drvdata(&dev->dev);
198 	int r = 0;
199 	int level;
200 
201 	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
202 			dev->props.power == FB_BLANK_UNBLANK)
203 		level = dev->props.brightness;
204 	else
205 		level = 0;
206 
207 	dev_dbg(&ddata->dsi->dev, "update brightness to %d\n", level);
208 
209 	mutex_lock(&ddata->lock);
210 
211 	if (ddata->enabled)
212 		r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
213 				      level);
214 
215 	mutex_unlock(&ddata->lock);
216 
217 	return r;
218 }
219 
220 static int dsicm_bl_get_intensity(struct backlight_device *dev)
221 {
222 	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
223 			dev->props.power == FB_BLANK_UNBLANK)
224 		return dev->props.brightness;
225 
226 	return 0;
227 }
228 
229 static const struct backlight_ops dsicm_bl_ops = {
230 	.get_brightness = dsicm_bl_get_intensity,
231 	.update_status  = dsicm_bl_update_status,
232 };
233 
234 static ssize_t num_dsi_errors_show(struct device *dev,
235 		struct device_attribute *attr, char *buf)
236 {
237 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
238 	u8 errors = 0;
239 	int r = -ENODEV;
240 
241 	mutex_lock(&ddata->lock);
242 
243 	if (ddata->enabled)
244 		r = dsicm_dcs_read_1(ddata, MIPI_DCS_GET_ERROR_COUNT_ON_DSI, &errors);
245 
246 	mutex_unlock(&ddata->lock);
247 
248 	if (r)
249 		return r;
250 
251 	return snprintf(buf, PAGE_SIZE, "%d\n", errors);
252 }
253 
254 static ssize_t hw_revision_show(struct device *dev,
255 		struct device_attribute *attr, char *buf)
256 {
257 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
258 	u8 id1, id2, id3;
259 	int r = -ENODEV;
260 
261 	mutex_lock(&ddata->lock);
262 
263 	if (ddata->enabled)
264 		r = dsicm_get_id(ddata, &id1, &id2, &id3);
265 
266 	mutex_unlock(&ddata->lock);
267 
268 	if (r)
269 		return r;
270 
271 	return snprintf(buf, PAGE_SIZE, "%02x.%02x.%02x\n", id1, id2, id3);
272 }
273 
274 static DEVICE_ATTR_RO(num_dsi_errors);
275 static DEVICE_ATTR_RO(hw_revision);
276 
277 static struct attribute *dsicm_attrs[] = {
278 	&dev_attr_num_dsi_errors.attr,
279 	&dev_attr_hw_revision.attr,
280 	NULL,
281 };
282 
283 static const struct attribute_group dsicm_attr_group = {
284 	.attrs = dsicm_attrs,
285 };
286 
287 static void dsicm_hw_reset(struct panel_drv_data *ddata)
288 {
289 	gpiod_set_value(ddata->reset_gpio, 1);
290 	udelay(10);
291 	/* reset the panel */
292 	gpiod_set_value(ddata->reset_gpio, 0);
293 	/* assert reset */
294 	udelay(10);
295 	gpiod_set_value(ddata->reset_gpio, 1);
296 	/* wait after releasing reset */
297 	usleep_range(5000, 10000);
298 }
299 
300 static int dsicm_power_on(struct panel_drv_data *ddata)
301 {
302 	u8 id1, id2, id3;
303 	int r;
304 
305 	dsicm_hw_reset(ddata);
306 
307 	ddata->dsi->mode_flags |= MIPI_DSI_MODE_LPM;
308 
309 	r = dsicm_sleep_out(ddata);
310 	if (r)
311 		goto err;
312 
313 	r = dsicm_get_id(ddata, &id1, &id2, &id3);
314 	if (r)
315 		goto err;
316 
317 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_DISPLAY_BRIGHTNESS, 0xff);
318 	if (r)
319 		goto err;
320 
321 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_WRITE_CONTROL_DISPLAY,
322 			(1<<2) | (1<<5));	/* BL | BCTRL */
323 	if (r)
324 		goto err;
325 
326 	r = mipi_dsi_dcs_set_pixel_format(ddata->dsi, MIPI_DCS_PIXEL_FMT_24BIT);
327 	if (r)
328 		goto err;
329 
330 	r = dsicm_set_update_window(ddata);
331 	if (r)
332 		goto err;
333 
334 	r = mipi_dsi_dcs_set_display_on(ddata->dsi);
335 	if (r)
336 		goto err;
337 
338 	if (ddata->panel_data->te_support) {
339 		r = mipi_dsi_dcs_set_tear_on(ddata->dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
340 		if (r)
341 			goto err;
342 	}
343 
344 	/* possible panel bug */
345 	msleep(100);
346 
347 	ddata->enabled = true;
348 
349 	if (!ddata->intro_printed) {
350 		dev_info(&ddata->dsi->dev, "panel revision %02x.%02x.%02x\n",
351 			id1, id2, id3);
352 		ddata->intro_printed = true;
353 	}
354 
355 	ddata->dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
356 
357 	return 0;
358 err:
359 	dev_err(&ddata->dsi->dev, "error while enabling panel, issuing HW reset\n");
360 
361 	dsicm_hw_reset(ddata);
362 
363 	return r;
364 }
365 
366 static int dsicm_power_off(struct panel_drv_data *ddata)
367 {
368 	int r;
369 
370 	ddata->enabled = false;
371 
372 	r = mipi_dsi_dcs_set_display_off(ddata->dsi);
373 	if (!r)
374 		r = dsicm_sleep_in(ddata);
375 
376 	if (r) {
377 		dev_err(&ddata->dsi->dev,
378 				"error disabling panel, issuing HW reset\n");
379 		dsicm_hw_reset(ddata);
380 	}
381 
382 	return r;
383 }
384 
385 static int dsicm_prepare(struct drm_panel *panel)
386 {
387 	struct panel_drv_data *ddata = panel_to_ddata(panel);
388 	int r;
389 
390 	r = regulator_bulk_enable(ARRAY_SIZE(ddata->supplies), ddata->supplies);
391 	if (r)
392 		dev_err(&ddata->dsi->dev, "failed to enable supplies: %d\n", r);
393 
394 	return r;
395 }
396 
397 static int dsicm_enable(struct drm_panel *panel)
398 {
399 	struct panel_drv_data *ddata = panel_to_ddata(panel);
400 	int r;
401 
402 	mutex_lock(&ddata->lock);
403 
404 	r = dsicm_power_on(ddata);
405 	if (r)
406 		goto err;
407 
408 	mutex_unlock(&ddata->lock);
409 
410 	dsicm_bl_power(ddata, true);
411 
412 	return 0;
413 err:
414 	dev_err(&ddata->dsi->dev, "enable failed (%d)\n", r);
415 	mutex_unlock(&ddata->lock);
416 	return r;
417 }
418 
419 static int dsicm_unprepare(struct drm_panel *panel)
420 {
421 	struct panel_drv_data *ddata = panel_to_ddata(panel);
422 	int r;
423 
424 	r = regulator_bulk_disable(ARRAY_SIZE(ddata->supplies), ddata->supplies);
425 	if (r)
426 		dev_err(&ddata->dsi->dev, "failed to disable supplies: %d\n", r);
427 
428 	return r;
429 }
430 
431 static int dsicm_disable(struct drm_panel *panel)
432 {
433 	struct panel_drv_data *ddata = panel_to_ddata(panel);
434 	int r;
435 
436 	dsicm_bl_power(ddata, false);
437 
438 	mutex_lock(&ddata->lock);
439 
440 	r = dsicm_power_off(ddata);
441 
442 	mutex_unlock(&ddata->lock);
443 
444 	return r;
445 }
446 
447 static int dsicm_get_modes(struct drm_panel *panel,
448 			   struct drm_connector *connector)
449 {
450 	struct panel_drv_data *ddata = panel_to_ddata(panel);
451 	struct drm_display_mode *mode;
452 
453 	mode = drm_mode_duplicate(connector->dev, &ddata->mode);
454 	if (!mode) {
455 		dev_err(&ddata->dsi->dev, "failed to add mode %ux%ux@%u kHz\n",
456 			ddata->mode.hdisplay, ddata->mode.vdisplay,
457 			ddata->mode.clock);
458 		return -ENOMEM;
459 	}
460 
461 	connector->display_info.width_mm = ddata->panel_data->width_mm;
462 	connector->display_info.height_mm = ddata->panel_data->height_mm;
463 
464 	drm_mode_probed_add(connector, mode);
465 
466 	return 1;
467 }
468 
469 static const struct drm_panel_funcs dsicm_panel_funcs = {
470 	.unprepare = dsicm_unprepare,
471 	.disable = dsicm_disable,
472 	.prepare = dsicm_prepare,
473 	.enable = dsicm_enable,
474 	.get_modes = dsicm_get_modes,
475 };
476 
477 static int dsicm_probe_of(struct mipi_dsi_device *dsi)
478 {
479 	struct backlight_device *backlight;
480 	struct panel_drv_data *ddata = mipi_dsi_get_drvdata(dsi);
481 	int err;
482 	struct drm_display_mode *mode = &ddata->mode;
483 
484 	ddata->reset_gpio = devm_gpiod_get(&dsi->dev, "reset", GPIOD_OUT_LOW);
485 	if (IS_ERR(ddata->reset_gpio)) {
486 		err = PTR_ERR(ddata->reset_gpio);
487 		dev_err(&dsi->dev, "reset gpio request failed: %d", err);
488 		return err;
489 	}
490 
491 	mode->hdisplay = mode->hsync_start = mode->hsync_end = mode->htotal =
492 		ddata->panel_data->xres;
493 	mode->vdisplay = mode->vsync_start = mode->vsync_end = mode->vtotal =
494 		ddata->panel_data->yres;
495 	mode->clock = ddata->panel_data->xres * ddata->panel_data->yres *
496 		ddata->panel_data->refresh / 1000;
497 	mode->width_mm = ddata->panel_data->width_mm;
498 	mode->height_mm = ddata->panel_data->height_mm;
499 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
500 	drm_mode_set_name(mode);
501 
502 	ddata->supplies[0].supply = "vpnl";
503 	ddata->supplies[1].supply = "vddi";
504 	err = devm_regulator_bulk_get(&dsi->dev, ARRAY_SIZE(ddata->supplies),
505 				      ddata->supplies);
506 	if (err)
507 		return err;
508 
509 	backlight = devm_of_find_backlight(&dsi->dev);
510 	if (IS_ERR(backlight))
511 		return PTR_ERR(backlight);
512 
513 	/* If no backlight device is found assume native backlight support */
514 	if (backlight)
515 		ddata->extbldev = backlight;
516 	else
517 		ddata->use_dsi_backlight = true;
518 
519 	return 0;
520 }
521 
522 static int dsicm_probe(struct mipi_dsi_device *dsi)
523 {
524 	struct panel_drv_data *ddata;
525 	struct backlight_device *bldev = NULL;
526 	struct device *dev = &dsi->dev;
527 	int r;
528 
529 	dev_dbg(dev, "probe\n");
530 
531 	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
532 	if (!ddata)
533 		return -ENOMEM;
534 
535 	mipi_dsi_set_drvdata(dsi, ddata);
536 	ddata->dsi = dsi;
537 
538 	ddata->panel_data = of_device_get_match_data(dev);
539 	if (!ddata->panel_data)
540 		return -ENODEV;
541 
542 	r = dsicm_probe_of(dsi);
543 	if (r)
544 		return r;
545 
546 	mutex_init(&ddata->lock);
547 
548 	dsicm_hw_reset(ddata);
549 
550 	drm_panel_init(&ddata->panel, dev, &dsicm_panel_funcs,
551 		       DRM_MODE_CONNECTOR_DSI);
552 
553 	if (ddata->use_dsi_backlight) {
554 		struct backlight_properties props = { 0 };
555 		props.max_brightness = 255;
556 		props.type = BACKLIGHT_RAW;
557 
558 		bldev = devm_backlight_device_register(dev, dev_name(dev),
559 			dev, ddata, &dsicm_bl_ops, &props);
560 		if (IS_ERR(bldev)) {
561 			r = PTR_ERR(bldev);
562 			goto err_bl;
563 		}
564 
565 		ddata->bldev = bldev;
566 	}
567 
568 	r = sysfs_create_group(&dev->kobj, &dsicm_attr_group);
569 	if (r) {
570 		dev_err(dev, "failed to create sysfs files\n");
571 		goto err_bl;
572 	}
573 
574 	dsi->lanes = 2;
575 	dsi->format = MIPI_DSI_FMT_RGB888;
576 	dsi->mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS |
577 			  MIPI_DSI_MODE_EOT_PACKET;
578 	dsi->hs_rate = ddata->panel_data->max_hs_rate;
579 	dsi->lp_rate = ddata->panel_data->max_lp_rate;
580 
581 	drm_panel_add(&ddata->panel);
582 
583 	r = mipi_dsi_attach(dsi);
584 	if (r < 0)
585 		goto err_dsi_attach;
586 
587 	return 0;
588 
589 err_dsi_attach:
590 	drm_panel_remove(&ddata->panel);
591 	sysfs_remove_group(&dsi->dev.kobj, &dsicm_attr_group);
592 err_bl:
593 	if (ddata->extbldev)
594 		put_device(&ddata->extbldev->dev);
595 
596 	return r;
597 }
598 
599 static int dsicm_remove(struct mipi_dsi_device *dsi)
600 {
601 	struct panel_drv_data *ddata = mipi_dsi_get_drvdata(dsi);
602 
603 	dev_dbg(&dsi->dev, "remove\n");
604 
605 	mipi_dsi_detach(dsi);
606 
607 	drm_panel_remove(&ddata->panel);
608 
609 	sysfs_remove_group(&dsi->dev.kobj, &dsicm_attr_group);
610 
611 	if (ddata->extbldev)
612 		put_device(&ddata->extbldev->dev);
613 
614 	return 0;
615 }
616 
617 static const struct dsic_panel_data taal_data = {
618 	.xres = 864,
619 	.yres = 480,
620 	.refresh = 60,
621 	.width_mm = 0,
622 	.height_mm = 0,
623 	.max_hs_rate = 300000000,
624 	.max_lp_rate = 10000000,
625 	.te_support = true,
626 };
627 
628 static const struct dsic_panel_data himalaya_data = {
629 	.xres = 480,
630 	.yres = 864,
631 	.refresh = 60,
632 	.width_mm = 49,
633 	.height_mm = 88,
634 	.max_hs_rate = 300000000,
635 	.max_lp_rate = 10000000,
636 	.te_support = false,
637 };
638 
639 static const struct dsic_panel_data droid4_data = {
640 	.xres = 540,
641 	.yres = 960,
642 	.refresh = 60,
643 	.width_mm = 50,
644 	.height_mm = 89,
645 	.max_hs_rate = 300000000,
646 	.max_lp_rate = 10000000,
647 	.te_support = false,
648 };
649 
650 static const struct of_device_id dsicm_of_match[] = {
651 	{ .compatible = "tpo,taal", .data = &taal_data },
652 	{ .compatible = "nokia,himalaya", &himalaya_data },
653 	{ .compatible = "motorola,droid4-panel", &droid4_data },
654 	{},
655 };
656 
657 MODULE_DEVICE_TABLE(of, dsicm_of_match);
658 
659 static struct mipi_dsi_driver dsicm_driver = {
660 	.probe = dsicm_probe,
661 	.remove = dsicm_remove,
662 	.driver = {
663 		.name = "panel-dsi-cm",
664 		.of_match_table = dsicm_of_match,
665 	},
666 };
667 module_mipi_dsi_driver(dsicm_driver);
668 
669 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
670 MODULE_DESCRIPTION("Generic DSI Command Mode Panel Driver");
671 MODULE_LICENSE("GPL");
672