1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic DSI Command Mode panel driver
4  *
5  * Copyright (C) 2013 Texas Instruments
6  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
7  */
8 
9 /* #define DEBUG */
10 
11 #include <linux/backlight.h>
12 #include <linux/delay.h>
13 #include <linux/err.h>
14 #include <linux/fb.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/interrupt.h>
17 #include <linux/jiffies.h>
18 #include <linux/mod_devicetable.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/sched/signal.h>
22 #include <linux/slab.h>
23 #include <linux/workqueue.h>
24 
25 #include <video/omapfb_dss.h>
26 #include <video/mipi_display.h>
27 
28 /* DSI Virtual channel. Hardcoded for now. */
29 #define TCH 0
30 
31 #define DCS_READ_NUM_ERRORS	0x05
32 #define DCS_BRIGHTNESS		0x51
33 #define DCS_CTRL_DISPLAY	0x53
34 #define DCS_GET_ID1		0xda
35 #define DCS_GET_ID2		0xdb
36 #define DCS_GET_ID3		0xdc
37 
38 struct panel_drv_data {
39 	struct omap_dss_device dssdev;
40 	struct omap_dss_device *in;
41 
42 	struct omap_video_timings timings;
43 
44 	struct platform_device *pdev;
45 
46 	struct mutex lock;
47 
48 	struct backlight_device *bldev;
49 
50 	unsigned long	hw_guard_end;	/* next value of jiffies when we can
51 					 * issue the next sleep in/out command
52 					 */
53 	unsigned long	hw_guard_wait;	/* max guard time in jiffies */
54 
55 	/* panel HW configuration from DT or platform data */
56 	struct gpio_desc *reset_gpio;
57 	struct gpio_desc *ext_te_gpio;
58 
59 	bool use_dsi_backlight;
60 
61 	struct omap_dsi_pin_config pin_config;
62 
63 	/* runtime variables */
64 	bool enabled;
65 
66 	bool te_enabled;
67 
68 	atomic_t do_update;
69 	int channel;
70 
71 	struct delayed_work te_timeout_work;
72 
73 	bool intro_printed;
74 
75 	bool ulps_enabled;
76 	unsigned ulps_timeout;
77 	struct delayed_work ulps_work;
78 };
79 
80 #define to_panel_data(p) container_of(p, struct panel_drv_data, dssdev)
81 
82 static irqreturn_t dsicm_te_isr(int irq, void *data);
83 static void dsicm_te_timeout_work_callback(struct work_struct *work);
84 static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable);
85 
86 static int dsicm_panel_reset(struct panel_drv_data *ddata);
87 
88 static void dsicm_ulps_work(struct work_struct *work);
89 
90 static void hw_guard_start(struct panel_drv_data *ddata, int guard_msec)
91 {
92 	ddata->hw_guard_wait = msecs_to_jiffies(guard_msec);
93 	ddata->hw_guard_end = jiffies + ddata->hw_guard_wait;
94 }
95 
96 static void hw_guard_wait(struct panel_drv_data *ddata)
97 {
98 	unsigned long wait = ddata->hw_guard_end - jiffies;
99 
100 	if ((long)wait > 0 && time_before_eq(wait, ddata->hw_guard_wait)) {
101 		set_current_state(TASK_UNINTERRUPTIBLE);
102 		schedule_timeout(wait);
103 	}
104 }
105 
106 static int dsicm_dcs_read_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 *data)
107 {
108 	struct omap_dss_device *in = ddata->in;
109 	int r;
110 	u8 buf[1];
111 
112 	r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd, buf, 1);
113 
114 	if (r < 0)
115 		return r;
116 
117 	*data = buf[0];
118 
119 	return 0;
120 }
121 
122 static int dsicm_dcs_write_0(struct panel_drv_data *ddata, u8 dcs_cmd)
123 {
124 	struct omap_dss_device *in = ddata->in;
125 	return in->ops.dsi->dcs_write(in, ddata->channel, &dcs_cmd, 1);
126 }
127 
128 static int dsicm_dcs_write_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 param)
129 {
130 	struct omap_dss_device *in = ddata->in;
131 	u8 buf[2] = { dcs_cmd, param };
132 
133 	return in->ops.dsi->dcs_write(in, ddata->channel, buf, 2);
134 }
135 
136 static int dsicm_sleep_in(struct panel_drv_data *ddata)
137 
138 {
139 	struct omap_dss_device *in = ddata->in;
140 	u8 cmd;
141 	int r;
142 
143 	hw_guard_wait(ddata);
144 
145 	cmd = MIPI_DCS_ENTER_SLEEP_MODE;
146 	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, &cmd, 1);
147 	if (r)
148 		return r;
149 
150 	hw_guard_start(ddata, 120);
151 
152 	usleep_range(5000, 10000);
153 
154 	return 0;
155 }
156 
157 static int dsicm_sleep_out(struct panel_drv_data *ddata)
158 {
159 	int r;
160 
161 	hw_guard_wait(ddata);
162 
163 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_EXIT_SLEEP_MODE);
164 	if (r)
165 		return r;
166 
167 	hw_guard_start(ddata, 120);
168 
169 	usleep_range(5000, 10000);
170 
171 	return 0;
172 }
173 
174 static int dsicm_get_id(struct panel_drv_data *ddata, u8 *id1, u8 *id2, u8 *id3)
175 {
176 	int r;
177 
178 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID1, id1);
179 	if (r)
180 		return r;
181 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID2, id2);
182 	if (r)
183 		return r;
184 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID3, id3);
185 	if (r)
186 		return r;
187 
188 	return 0;
189 }
190 
191 static int dsicm_set_update_window(struct panel_drv_data *ddata,
192 		u16 x, u16 y, u16 w, u16 h)
193 {
194 	struct omap_dss_device *in = ddata->in;
195 	int r;
196 	u16 x1 = x;
197 	u16 x2 = x + w - 1;
198 	u16 y1 = y;
199 	u16 y2 = y + h - 1;
200 
201 	u8 buf[5];
202 	buf[0] = MIPI_DCS_SET_COLUMN_ADDRESS;
203 	buf[1] = (x1 >> 8) & 0xff;
204 	buf[2] = (x1 >> 0) & 0xff;
205 	buf[3] = (x2 >> 8) & 0xff;
206 	buf[4] = (x2 >> 0) & 0xff;
207 
208 	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, buf, sizeof(buf));
209 	if (r)
210 		return r;
211 
212 	buf[0] = MIPI_DCS_SET_PAGE_ADDRESS;
213 	buf[1] = (y1 >> 8) & 0xff;
214 	buf[2] = (y1 >> 0) & 0xff;
215 	buf[3] = (y2 >> 8) & 0xff;
216 	buf[4] = (y2 >> 0) & 0xff;
217 
218 	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, buf, sizeof(buf));
219 	if (r)
220 		return r;
221 
222 	in->ops.dsi->bta_sync(in, ddata->channel);
223 
224 	return r;
225 }
226 
227 static void dsicm_queue_ulps_work(struct panel_drv_data *ddata)
228 {
229 	if (ddata->ulps_timeout > 0)
230 		schedule_delayed_work(&ddata->ulps_work,
231 				msecs_to_jiffies(ddata->ulps_timeout));
232 }
233 
234 static void dsicm_cancel_ulps_work(struct panel_drv_data *ddata)
235 {
236 	cancel_delayed_work(&ddata->ulps_work);
237 }
238 
239 static int dsicm_enter_ulps(struct panel_drv_data *ddata)
240 {
241 	struct omap_dss_device *in = ddata->in;
242 	int r;
243 
244 	if (ddata->ulps_enabled)
245 		return 0;
246 
247 	dsicm_cancel_ulps_work(ddata);
248 
249 	r = _dsicm_enable_te(ddata, false);
250 	if (r)
251 		goto err;
252 
253 	if (ddata->ext_te_gpio)
254 		disable_irq(gpiod_to_irq(ddata->ext_te_gpio));
255 
256 	in->ops.dsi->disable(in, false, true);
257 
258 	ddata->ulps_enabled = true;
259 
260 	return 0;
261 
262 err:
263 	dev_err(&ddata->pdev->dev, "enter ULPS failed");
264 	dsicm_panel_reset(ddata);
265 
266 	ddata->ulps_enabled = false;
267 
268 	dsicm_queue_ulps_work(ddata);
269 
270 	return r;
271 }
272 
273 static int dsicm_exit_ulps(struct panel_drv_data *ddata)
274 {
275 	struct omap_dss_device *in = ddata->in;
276 	int r;
277 
278 	if (!ddata->ulps_enabled)
279 		return 0;
280 
281 	r = in->ops.dsi->enable(in);
282 	if (r) {
283 		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
284 		goto err1;
285 	}
286 
287 	in->ops.dsi->enable_hs(in, ddata->channel, true);
288 
289 	r = _dsicm_enable_te(ddata, true);
290 	if (r) {
291 		dev_err(&ddata->pdev->dev, "failed to re-enable TE");
292 		goto err2;
293 	}
294 
295 	if (ddata->ext_te_gpio)
296 		enable_irq(gpiod_to_irq(ddata->ext_te_gpio));
297 
298 	dsicm_queue_ulps_work(ddata);
299 
300 	ddata->ulps_enabled = false;
301 
302 	return 0;
303 
304 err2:
305 	dev_err(&ddata->pdev->dev, "failed to exit ULPS");
306 
307 	r = dsicm_panel_reset(ddata);
308 	if (!r) {
309 		if (ddata->ext_te_gpio)
310 			enable_irq(gpiod_to_irq(ddata->ext_te_gpio));
311 		ddata->ulps_enabled = false;
312 	}
313 err1:
314 	dsicm_queue_ulps_work(ddata);
315 
316 	return r;
317 }
318 
319 static int dsicm_wake_up(struct panel_drv_data *ddata)
320 {
321 	if (ddata->ulps_enabled)
322 		return dsicm_exit_ulps(ddata);
323 
324 	dsicm_cancel_ulps_work(ddata);
325 	dsicm_queue_ulps_work(ddata);
326 	return 0;
327 }
328 
329 static int dsicm_bl_update_status(struct backlight_device *dev)
330 {
331 	struct panel_drv_data *ddata = dev_get_drvdata(&dev->dev);
332 	struct omap_dss_device *in = ddata->in;
333 	int r;
334 	int level = backlight_get_brightness(dev);
335 
336 	dev_dbg(&ddata->pdev->dev, "update brightness to %d\n", level);
337 
338 	mutex_lock(&ddata->lock);
339 
340 	if (ddata->enabled) {
341 		in->ops.dsi->bus_lock(in);
342 
343 		r = dsicm_wake_up(ddata);
344 		if (!r)
345 			r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, level);
346 
347 		in->ops.dsi->bus_unlock(in);
348 	} else {
349 		r = 0;
350 	}
351 
352 	mutex_unlock(&ddata->lock);
353 
354 	return r;
355 }
356 
357 static int dsicm_bl_get_intensity(struct backlight_device *dev)
358 {
359 	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
360 			dev->props.power == FB_BLANK_UNBLANK)
361 		return dev->props.brightness;
362 
363 	return 0;
364 }
365 
366 static const struct backlight_ops dsicm_bl_ops = {
367 	.get_brightness = dsicm_bl_get_intensity,
368 	.update_status  = dsicm_bl_update_status,
369 };
370 
371 static void dsicm_get_resolution(struct omap_dss_device *dssdev,
372 		u16 *xres, u16 *yres)
373 {
374 	*xres = dssdev->panel.timings.x_res;
375 	*yres = dssdev->panel.timings.y_res;
376 }
377 
378 static ssize_t dsicm_num_errors_show(struct device *dev,
379 		struct device_attribute *attr, char *buf)
380 {
381 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
382 	struct omap_dss_device *in = ddata->in;
383 	u8 errors = 0;
384 	int r;
385 
386 	mutex_lock(&ddata->lock);
387 
388 	if (ddata->enabled) {
389 		in->ops.dsi->bus_lock(in);
390 
391 		r = dsicm_wake_up(ddata);
392 		if (!r)
393 			r = dsicm_dcs_read_1(ddata, DCS_READ_NUM_ERRORS,
394 					&errors);
395 
396 		in->ops.dsi->bus_unlock(in);
397 	} else {
398 		r = -ENODEV;
399 	}
400 
401 	mutex_unlock(&ddata->lock);
402 
403 	if (r)
404 		return r;
405 
406 	return sysfs_emit(buf, "%d\n", errors);
407 }
408 
409 static ssize_t dsicm_hw_revision_show(struct device *dev,
410 		struct device_attribute *attr, char *buf)
411 {
412 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
413 	struct omap_dss_device *in = ddata->in;
414 	u8 id1, id2, id3;
415 	int r;
416 
417 	mutex_lock(&ddata->lock);
418 
419 	if (ddata->enabled) {
420 		in->ops.dsi->bus_lock(in);
421 
422 		r = dsicm_wake_up(ddata);
423 		if (!r)
424 			r = dsicm_get_id(ddata, &id1, &id2, &id3);
425 
426 		in->ops.dsi->bus_unlock(in);
427 	} else {
428 		r = -ENODEV;
429 	}
430 
431 	mutex_unlock(&ddata->lock);
432 
433 	if (r)
434 		return r;
435 
436 	return sysfs_emit(buf, "%02x.%02x.%02x\n", id1, id2, id3);
437 }
438 
439 static ssize_t dsicm_store_ulps(struct device *dev,
440 		struct device_attribute *attr,
441 		const char *buf, size_t count)
442 {
443 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
444 	struct omap_dss_device *in = ddata->in;
445 	unsigned long t;
446 	int r;
447 
448 	r = kstrtoul(buf, 0, &t);
449 	if (r)
450 		return r;
451 
452 	mutex_lock(&ddata->lock);
453 
454 	if (ddata->enabled) {
455 		in->ops.dsi->bus_lock(in);
456 
457 		if (t)
458 			r = dsicm_enter_ulps(ddata);
459 		else
460 			r = dsicm_wake_up(ddata);
461 
462 		in->ops.dsi->bus_unlock(in);
463 	}
464 
465 	mutex_unlock(&ddata->lock);
466 
467 	if (r)
468 		return r;
469 
470 	return count;
471 }
472 
473 static ssize_t dsicm_show_ulps(struct device *dev,
474 		struct device_attribute *attr,
475 		char *buf)
476 {
477 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
478 	unsigned t;
479 
480 	mutex_lock(&ddata->lock);
481 	t = ddata->ulps_enabled;
482 	mutex_unlock(&ddata->lock);
483 
484 	return sysfs_emit(buf, "%u\n", t);
485 }
486 
487 static ssize_t dsicm_store_ulps_timeout(struct device *dev,
488 		struct device_attribute *attr,
489 		const char *buf, size_t count)
490 {
491 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
492 	struct omap_dss_device *in = ddata->in;
493 	unsigned long t;
494 	int r;
495 
496 	r = kstrtoul(buf, 0, &t);
497 	if (r)
498 		return r;
499 
500 	mutex_lock(&ddata->lock);
501 	ddata->ulps_timeout = t;
502 
503 	if (ddata->enabled) {
504 		/* dsicm_wake_up will restart the timer */
505 		in->ops.dsi->bus_lock(in);
506 		r = dsicm_wake_up(ddata);
507 		in->ops.dsi->bus_unlock(in);
508 	}
509 
510 	mutex_unlock(&ddata->lock);
511 
512 	if (r)
513 		return r;
514 
515 	return count;
516 }
517 
518 static ssize_t dsicm_show_ulps_timeout(struct device *dev,
519 		struct device_attribute *attr,
520 		char *buf)
521 {
522 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
523 	unsigned t;
524 
525 	mutex_lock(&ddata->lock);
526 	t = ddata->ulps_timeout;
527 	mutex_unlock(&ddata->lock);
528 
529 	return sysfs_emit(buf, "%u\n", t);
530 }
531 
532 static DEVICE_ATTR(num_dsi_errors, S_IRUGO, dsicm_num_errors_show, NULL);
533 static DEVICE_ATTR(hw_revision, S_IRUGO, dsicm_hw_revision_show, NULL);
534 static DEVICE_ATTR(ulps, S_IRUGO | S_IWUSR,
535 		dsicm_show_ulps, dsicm_store_ulps);
536 static DEVICE_ATTR(ulps_timeout, S_IRUGO | S_IWUSR,
537 		dsicm_show_ulps_timeout, dsicm_store_ulps_timeout);
538 
539 static struct attribute *dsicm_attrs[] = {
540 	&dev_attr_num_dsi_errors.attr,
541 	&dev_attr_hw_revision.attr,
542 	&dev_attr_ulps.attr,
543 	&dev_attr_ulps_timeout.attr,
544 	NULL,
545 };
546 
547 static const struct attribute_group dsicm_attr_group = {
548 	.attrs = dsicm_attrs,
549 };
550 
551 static void dsicm_hw_reset(struct panel_drv_data *ddata)
552 {
553 	/*
554 	 * Note that we appear to activate the reset line here. However
555 	 * existing DTSes specified incorrect polarity for it (active high),
556 	 * so in fact this deasserts the reset line.
557 	 */
558 	gpiod_set_value_cansleep(ddata->reset_gpio, 1);
559 	udelay(10);
560 	/* reset the panel */
561 	gpiod_set_value_cansleep(ddata->reset_gpio, 0);
562 	/* keep reset asserted */
563 	udelay(10);
564 	/* release reset line */
565 	gpiod_set_value_cansleep(ddata->reset_gpio, 1);
566 	/* wait after releasing reset */
567 	usleep_range(5000, 10000);
568 }
569 
570 static int dsicm_power_on(struct panel_drv_data *ddata)
571 {
572 	struct omap_dss_device *in = ddata->in;
573 	u8 id1, id2, id3;
574 	int r;
575 	struct omap_dss_dsi_config dsi_config = {
576 		.mode = OMAP_DSS_DSI_CMD_MODE,
577 		.pixel_format = OMAP_DSS_DSI_FMT_RGB888,
578 		.timings = &ddata->timings,
579 		.hs_clk_min = 150000000,
580 		.hs_clk_max = 300000000,
581 		.lp_clk_min = 7000000,
582 		.lp_clk_max = 10000000,
583 	};
584 
585 	if (ddata->pin_config.num_pins > 0) {
586 		r = in->ops.dsi->configure_pins(in, &ddata->pin_config);
587 		if (r) {
588 			dev_err(&ddata->pdev->dev,
589 				"failed to configure DSI pins\n");
590 			goto err0;
591 		}
592 	}
593 
594 	r = in->ops.dsi->set_config(in, &dsi_config);
595 	if (r) {
596 		dev_err(&ddata->pdev->dev, "failed to configure DSI\n");
597 		goto err0;
598 	}
599 
600 	r = in->ops.dsi->enable(in);
601 	if (r) {
602 		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
603 		goto err0;
604 	}
605 
606 	dsicm_hw_reset(ddata);
607 
608 	in->ops.dsi->enable_hs(in, ddata->channel, false);
609 
610 	r = dsicm_sleep_out(ddata);
611 	if (r)
612 		goto err;
613 
614 	r = dsicm_get_id(ddata, &id1, &id2, &id3);
615 	if (r)
616 		goto err;
617 
618 	r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, 0xff);
619 	if (r)
620 		goto err;
621 
622 	r = dsicm_dcs_write_1(ddata, DCS_CTRL_DISPLAY,
623 			(1<<2) | (1<<5));	/* BL | BCTRL */
624 	if (r)
625 		goto err;
626 
627 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_PIXEL_FORMAT,
628 		MIPI_DCS_PIXEL_FMT_24BIT);
629 	if (r)
630 		goto err;
631 
632 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_ON);
633 	if (r)
634 		goto err;
635 
636 	r = _dsicm_enable_te(ddata, ddata->te_enabled);
637 	if (r)
638 		goto err;
639 
640 	r = in->ops.dsi->enable_video_output(in, ddata->channel);
641 	if (r)
642 		goto err;
643 
644 	ddata->enabled = 1;
645 
646 	if (!ddata->intro_printed) {
647 		dev_info(&ddata->pdev->dev, "panel revision %02x.%02x.%02x\n",
648 			id1, id2, id3);
649 		ddata->intro_printed = true;
650 	}
651 
652 	in->ops.dsi->enable_hs(in, ddata->channel, true);
653 
654 	return 0;
655 err:
656 	dev_err(&ddata->pdev->dev, "error while enabling panel, issuing HW reset\n");
657 
658 	dsicm_hw_reset(ddata);
659 
660 	in->ops.dsi->disable(in, true, false);
661 err0:
662 	return r;
663 }
664 
665 static void dsicm_power_off(struct panel_drv_data *ddata)
666 {
667 	struct omap_dss_device *in = ddata->in;
668 	int r;
669 
670 	in->ops.dsi->disable_video_output(in, ddata->channel);
671 
672 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_OFF);
673 	if (!r)
674 		r = dsicm_sleep_in(ddata);
675 
676 	if (r) {
677 		dev_err(&ddata->pdev->dev,
678 				"error disabling panel, issuing HW reset\n");
679 		dsicm_hw_reset(ddata);
680 	}
681 
682 	in->ops.dsi->disable(in, true, false);
683 
684 	ddata->enabled = 0;
685 }
686 
687 static int dsicm_panel_reset(struct panel_drv_data *ddata)
688 {
689 	dev_err(&ddata->pdev->dev, "performing LCD reset\n");
690 
691 	dsicm_power_off(ddata);
692 	dsicm_hw_reset(ddata);
693 	return dsicm_power_on(ddata);
694 }
695 
696 static int dsicm_connect(struct omap_dss_device *dssdev)
697 {
698 	struct panel_drv_data *ddata = to_panel_data(dssdev);
699 	struct omap_dss_device *in = ddata->in;
700 	struct device *dev = &ddata->pdev->dev;
701 	int r;
702 
703 	if (omapdss_device_is_connected(dssdev))
704 		return 0;
705 
706 	r = in->ops.dsi->connect(in, dssdev);
707 	if (r) {
708 		dev_err(dev, "Failed to connect to video source\n");
709 		return r;
710 	}
711 
712 	r = in->ops.dsi->request_vc(ddata->in, &ddata->channel);
713 	if (r) {
714 		dev_err(dev, "failed to get virtual channel\n");
715 		goto err_req_vc;
716 	}
717 
718 	r = in->ops.dsi->set_vc_id(ddata->in, ddata->channel, TCH);
719 	if (r) {
720 		dev_err(dev, "failed to set VC_ID\n");
721 		goto err_vc_id;
722 	}
723 
724 	return 0;
725 
726 err_vc_id:
727 	in->ops.dsi->release_vc(ddata->in, ddata->channel);
728 err_req_vc:
729 	in->ops.dsi->disconnect(in, dssdev);
730 	return r;
731 }
732 
733 static void dsicm_disconnect(struct omap_dss_device *dssdev)
734 {
735 	struct panel_drv_data *ddata = to_panel_data(dssdev);
736 	struct omap_dss_device *in = ddata->in;
737 
738 	if (!omapdss_device_is_connected(dssdev))
739 		return;
740 
741 	in->ops.dsi->release_vc(in, ddata->channel);
742 	in->ops.dsi->disconnect(in, dssdev);
743 }
744 
745 static int dsicm_enable(struct omap_dss_device *dssdev)
746 {
747 	struct panel_drv_data *ddata = to_panel_data(dssdev);
748 	struct omap_dss_device *in = ddata->in;
749 	int r;
750 
751 	dev_dbg(&ddata->pdev->dev, "enable\n");
752 
753 	mutex_lock(&ddata->lock);
754 
755 	if (!omapdss_device_is_connected(dssdev)) {
756 		r = -ENODEV;
757 		goto err;
758 	}
759 
760 	if (omapdss_device_is_enabled(dssdev)) {
761 		r = 0;
762 		goto err;
763 	}
764 
765 	in->ops.dsi->bus_lock(in);
766 
767 	r = dsicm_power_on(ddata);
768 
769 	in->ops.dsi->bus_unlock(in);
770 
771 	if (r)
772 		goto err;
773 
774 	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
775 
776 	mutex_unlock(&ddata->lock);
777 
778 	return 0;
779 err:
780 	dev_dbg(&ddata->pdev->dev, "enable failed\n");
781 	mutex_unlock(&ddata->lock);
782 	return r;
783 }
784 
785 static void dsicm_disable(struct omap_dss_device *dssdev)
786 {
787 	struct panel_drv_data *ddata = to_panel_data(dssdev);
788 	struct omap_dss_device *in = ddata->in;
789 	int r;
790 
791 	dev_dbg(&ddata->pdev->dev, "disable\n");
792 
793 	mutex_lock(&ddata->lock);
794 
795 	dsicm_cancel_ulps_work(ddata);
796 
797 	in->ops.dsi->bus_lock(in);
798 
799 	if (omapdss_device_is_enabled(dssdev)) {
800 		r = dsicm_wake_up(ddata);
801 		if (!r)
802 			dsicm_power_off(ddata);
803 	}
804 
805 	in->ops.dsi->bus_unlock(in);
806 
807 	dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
808 
809 	mutex_unlock(&ddata->lock);
810 }
811 
812 static void dsicm_framedone_cb(int err, void *data)
813 {
814 	struct panel_drv_data *ddata = data;
815 	struct omap_dss_device *in = ddata->in;
816 
817 	dev_dbg(&ddata->pdev->dev, "framedone, err %d\n", err);
818 	in->ops.dsi->bus_unlock(ddata->in);
819 }
820 
821 static irqreturn_t dsicm_te_isr(int irq, void *data)
822 {
823 	struct panel_drv_data *ddata = data;
824 	struct omap_dss_device *in = ddata->in;
825 	int old;
826 	int r;
827 
828 	old = atomic_cmpxchg(&ddata->do_update, 1, 0);
829 
830 	if (old) {
831 		cancel_delayed_work(&ddata->te_timeout_work);
832 
833 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
834 				ddata);
835 		if (r)
836 			goto err;
837 	}
838 
839 	return IRQ_HANDLED;
840 err:
841 	dev_err(&ddata->pdev->dev, "start update failed\n");
842 	in->ops.dsi->bus_unlock(in);
843 	return IRQ_HANDLED;
844 }
845 
846 static void dsicm_te_timeout_work_callback(struct work_struct *work)
847 {
848 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
849 					te_timeout_work.work);
850 	struct omap_dss_device *in = ddata->in;
851 
852 	dev_err(&ddata->pdev->dev, "TE not received for 250ms!\n");
853 
854 	atomic_set(&ddata->do_update, 0);
855 	in->ops.dsi->bus_unlock(in);
856 }
857 
858 static int dsicm_update(struct omap_dss_device *dssdev,
859 				    u16 x, u16 y, u16 w, u16 h)
860 {
861 	struct panel_drv_data *ddata = to_panel_data(dssdev);
862 	struct omap_dss_device *in = ddata->in;
863 	int r;
864 
865 	dev_dbg(&ddata->pdev->dev, "update %d, %d, %d x %d\n", x, y, w, h);
866 
867 	mutex_lock(&ddata->lock);
868 	in->ops.dsi->bus_lock(in);
869 
870 	r = dsicm_wake_up(ddata);
871 	if (r)
872 		goto err;
873 
874 	if (!ddata->enabled) {
875 		r = 0;
876 		goto err;
877 	}
878 
879 	/* XXX no need to send this every frame, but dsi break if not done */
880 	r = dsicm_set_update_window(ddata, 0, 0,
881 			dssdev->panel.timings.x_res,
882 			dssdev->panel.timings.y_res);
883 	if (r)
884 		goto err;
885 
886 	if (ddata->te_enabled && ddata->ext_te_gpio) {
887 		schedule_delayed_work(&ddata->te_timeout_work,
888 				msecs_to_jiffies(250));
889 		atomic_set(&ddata->do_update, 1);
890 	} else {
891 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
892 				ddata);
893 		if (r)
894 			goto err;
895 	}
896 
897 	/* note: no bus_unlock here. unlock is in framedone_cb */
898 	mutex_unlock(&ddata->lock);
899 	return 0;
900 err:
901 	in->ops.dsi->bus_unlock(in);
902 	mutex_unlock(&ddata->lock);
903 	return r;
904 }
905 
906 static int dsicm_sync(struct omap_dss_device *dssdev)
907 {
908 	struct panel_drv_data *ddata = to_panel_data(dssdev);
909 	struct omap_dss_device *in = ddata->in;
910 
911 	dev_dbg(&ddata->pdev->dev, "sync\n");
912 
913 	mutex_lock(&ddata->lock);
914 	in->ops.dsi->bus_lock(in);
915 	in->ops.dsi->bus_unlock(in);
916 	mutex_unlock(&ddata->lock);
917 
918 	dev_dbg(&ddata->pdev->dev, "sync done\n");
919 
920 	return 0;
921 }
922 
923 static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable)
924 {
925 	struct omap_dss_device *in = ddata->in;
926 	int r;
927 
928 	if (enable)
929 		r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_TEAR_ON, 0);
930 	else
931 		r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_TEAR_OFF);
932 
933 	if (!ddata->ext_te_gpio)
934 		in->ops.dsi->enable_te(in, enable);
935 
936 	/* possible panel bug */
937 	msleep(100);
938 
939 	return r;
940 }
941 
942 static int dsicm_enable_te(struct omap_dss_device *dssdev, bool enable)
943 {
944 	struct panel_drv_data *ddata = to_panel_data(dssdev);
945 	struct omap_dss_device *in = ddata->in;
946 	int r;
947 
948 	mutex_lock(&ddata->lock);
949 
950 	if (ddata->te_enabled == enable)
951 		goto end;
952 
953 	in->ops.dsi->bus_lock(in);
954 
955 	if (ddata->enabled) {
956 		r = dsicm_wake_up(ddata);
957 		if (r)
958 			goto err;
959 
960 		r = _dsicm_enable_te(ddata, enable);
961 		if (r)
962 			goto err;
963 	}
964 
965 	ddata->te_enabled = enable;
966 
967 	in->ops.dsi->bus_unlock(in);
968 end:
969 	mutex_unlock(&ddata->lock);
970 
971 	return 0;
972 err:
973 	in->ops.dsi->bus_unlock(in);
974 	mutex_unlock(&ddata->lock);
975 
976 	return r;
977 }
978 
979 static int dsicm_get_te(struct omap_dss_device *dssdev)
980 {
981 	struct panel_drv_data *ddata = to_panel_data(dssdev);
982 	int r;
983 
984 	mutex_lock(&ddata->lock);
985 	r = ddata->te_enabled;
986 	mutex_unlock(&ddata->lock);
987 
988 	return r;
989 }
990 
991 static int dsicm_memory_read(struct omap_dss_device *dssdev,
992 		void *buf, size_t size,
993 		u16 x, u16 y, u16 w, u16 h)
994 {
995 	struct panel_drv_data *ddata = to_panel_data(dssdev);
996 	struct omap_dss_device *in = ddata->in;
997 	int r;
998 	int first = 1;
999 	int plen;
1000 	unsigned buf_used = 0;
1001 
1002 	if (size < w * h * 3)
1003 		return -ENOMEM;
1004 
1005 	mutex_lock(&ddata->lock);
1006 
1007 	if (!ddata->enabled) {
1008 		r = -ENODEV;
1009 		goto err1;
1010 	}
1011 
1012 	size = min(w * h * 3,
1013 			dssdev->panel.timings.x_res *
1014 			dssdev->panel.timings.y_res * 3);
1015 
1016 	in->ops.dsi->bus_lock(in);
1017 
1018 	r = dsicm_wake_up(ddata);
1019 	if (r)
1020 		goto err2;
1021 
1022 	/* plen 1 or 2 goes into short packet. until checksum error is fixed,
1023 	 * use short packets. plen 32 works, but bigger packets seem to cause
1024 	 * an error. */
1025 	if (size % 2)
1026 		plen = 1;
1027 	else
1028 		plen = 2;
1029 
1030 	dsicm_set_update_window(ddata, x, y, w, h);
1031 
1032 	r = in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, plen);
1033 	if (r)
1034 		goto err2;
1035 
1036 	while (buf_used < size) {
1037 		u8 dcs_cmd = first ? 0x2e : 0x3e;
1038 		first = 0;
1039 
1040 		r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd,
1041 				buf + buf_used, size - buf_used);
1042 
1043 		if (r < 0) {
1044 			dev_err(dssdev->dev, "read error\n");
1045 			goto err3;
1046 		}
1047 
1048 		buf_used += r;
1049 
1050 		if (r < plen) {
1051 			dev_err(&ddata->pdev->dev, "short read\n");
1052 			break;
1053 		}
1054 
1055 		if (signal_pending(current)) {
1056 			dev_err(&ddata->pdev->dev, "signal pending, "
1057 					"aborting memory read\n");
1058 			r = -ERESTARTSYS;
1059 			goto err3;
1060 		}
1061 	}
1062 
1063 	r = buf_used;
1064 
1065 err3:
1066 	in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, 1);
1067 err2:
1068 	in->ops.dsi->bus_unlock(in);
1069 err1:
1070 	mutex_unlock(&ddata->lock);
1071 	return r;
1072 }
1073 
1074 static void dsicm_ulps_work(struct work_struct *work)
1075 {
1076 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
1077 			ulps_work.work);
1078 	struct omap_dss_device *dssdev = &ddata->dssdev;
1079 	struct omap_dss_device *in = ddata->in;
1080 
1081 	mutex_lock(&ddata->lock);
1082 
1083 	if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE || !ddata->enabled) {
1084 		mutex_unlock(&ddata->lock);
1085 		return;
1086 	}
1087 
1088 	in->ops.dsi->bus_lock(in);
1089 
1090 	dsicm_enter_ulps(ddata);
1091 
1092 	in->ops.dsi->bus_unlock(in);
1093 	mutex_unlock(&ddata->lock);
1094 }
1095 
1096 static struct omap_dss_driver dsicm_ops = {
1097 	.connect	= dsicm_connect,
1098 	.disconnect	= dsicm_disconnect,
1099 
1100 	.enable		= dsicm_enable,
1101 	.disable	= dsicm_disable,
1102 
1103 	.update		= dsicm_update,
1104 	.sync		= dsicm_sync,
1105 
1106 	.get_resolution	= dsicm_get_resolution,
1107 	.get_recommended_bpp = omapdss_default_get_recommended_bpp,
1108 
1109 	.enable_te	= dsicm_enable_te,
1110 	.get_te		= dsicm_get_te,
1111 
1112 	.memory_read	= dsicm_memory_read,
1113 };
1114 
1115 static int dsicm_probe(struct platform_device *pdev)
1116 {
1117 	struct backlight_properties props;
1118 	struct panel_drv_data *ddata;
1119 	struct backlight_device *bldev = NULL;
1120 	struct device *dev = &pdev->dev;
1121 	struct omap_dss_device *dssdev;
1122 	int r;
1123 
1124 	dev_dbg(dev, "probe\n");
1125 
1126 	if (!pdev->dev.of_node)
1127 		return -ENODEV;
1128 
1129 	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
1130 	if (!ddata)
1131 		return -ENOMEM;
1132 
1133 	platform_set_drvdata(pdev, ddata);
1134 	ddata->pdev = pdev;
1135 
1136 	ddata->in = omapdss_of_find_source_for_first_ep(pdev->dev.of_node);
1137 	r = PTR_ERR_OR_ZERO(ddata->in);
1138 	if (r) {
1139 		dev_err(&pdev->dev, "failed to find video source: %d\n", r);
1140 		return r;
1141 	}
1142 
1143 	ddata->timings.x_res = 864;
1144 	ddata->timings.y_res = 480;
1145 	ddata->timings.pixelclock = 864 * 480 * 60;
1146 
1147 	dssdev = &ddata->dssdev;
1148 	dssdev->dev = dev;
1149 	dssdev->driver = &dsicm_ops;
1150 	dssdev->panel.timings = ddata->timings;
1151 	dssdev->type = OMAP_DISPLAY_TYPE_DSI;
1152 	dssdev->owner = THIS_MODULE;
1153 
1154 	dssdev->panel.dsi_pix_fmt = OMAP_DSS_DSI_FMT_RGB888;
1155 	dssdev->caps = OMAP_DSS_DISPLAY_CAP_MANUAL_UPDATE |
1156 		OMAP_DSS_DISPLAY_CAP_TEAR_ELIM;
1157 
1158 	r = omapdss_register_display(dssdev);
1159 	if (r) {
1160 		dev_err(dev, "Failed to register panel\n");
1161 		goto err_reg;
1162 	}
1163 
1164 	mutex_init(&ddata->lock);
1165 
1166 	atomic_set(&ddata->do_update, 0);
1167 
1168 	ddata->reset_gpio = devm_gpiod_get(&pdev->dev, "reset", GPIOD_OUT_LOW);
1169 	r = PTR_ERR_OR_ZERO(ddata->reset_gpio);
1170 	if (r) {
1171 		dev_err(&pdev->dev, "Failed to request reset gpio: %d\n", r);
1172 		return r;
1173 	}
1174 
1175 	gpiod_set_consumer_name(ddata->reset_gpio, "taal rst");
1176 
1177 	ddata->ext_te_gpio = devm_gpiod_get_optional(&pdev->dev, "te",
1178 						     GPIOD_IN);
1179 	r = PTR_ERR_OR_ZERO(ddata->ext_te_gpio);
1180 	if (r) {
1181 		dev_err(&pdev->dev, "Failed to request TE gpio: %d\n", r);
1182 		return r;
1183 	}
1184 
1185 	if (ddata->ext_te_gpio) {
1186 		gpiod_set_consumer_name(ddata->ext_te_gpio, "taal irq");
1187 
1188 		r = devm_request_irq(dev, gpiod_to_irq(ddata->ext_te_gpio),
1189 				dsicm_te_isr,
1190 				IRQF_TRIGGER_RISING,
1191 				"taal vsync", ddata);
1192 
1193 		if (r) {
1194 			dev_err(dev, "IRQ request failed\n");
1195 			return r;
1196 		}
1197 
1198 		INIT_DEFERRABLE_WORK(&ddata->te_timeout_work,
1199 					dsicm_te_timeout_work_callback);
1200 
1201 		dev_dbg(dev, "Using GPIO TE\n");
1202 	}
1203 
1204 	INIT_DELAYED_WORK(&ddata->ulps_work, dsicm_ulps_work);
1205 
1206 	dsicm_hw_reset(ddata);
1207 
1208 	if (ddata->use_dsi_backlight) {
1209 		memset(&props, 0, sizeof(struct backlight_properties));
1210 		props.max_brightness = 255;
1211 
1212 		props.type = BACKLIGHT_RAW;
1213 		bldev = backlight_device_register(dev_name(dev),
1214 				dev, ddata, &dsicm_bl_ops, &props);
1215 		if (IS_ERR(bldev)) {
1216 			r = PTR_ERR(bldev);
1217 			goto err_reg;
1218 		}
1219 
1220 		ddata->bldev = bldev;
1221 
1222 		bldev->props.fb_blank = FB_BLANK_UNBLANK;
1223 		bldev->props.power = FB_BLANK_UNBLANK;
1224 		bldev->props.brightness = 255;
1225 
1226 		dsicm_bl_update_status(bldev);
1227 	}
1228 
1229 	r = sysfs_create_group(&dev->kobj, &dsicm_attr_group);
1230 	if (r) {
1231 		dev_err(dev, "failed to create sysfs files\n");
1232 		goto err_sysfs_create;
1233 	}
1234 
1235 	return 0;
1236 
1237 err_sysfs_create:
1238 	if (bldev != NULL)
1239 		backlight_device_unregister(bldev);
1240 err_reg:
1241 	return r;
1242 }
1243 
1244 static int __exit dsicm_remove(struct platform_device *pdev)
1245 {
1246 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
1247 	struct omap_dss_device *dssdev = &ddata->dssdev;
1248 	struct backlight_device *bldev;
1249 
1250 	dev_dbg(&pdev->dev, "remove\n");
1251 
1252 	omapdss_unregister_display(dssdev);
1253 
1254 	dsicm_disable(dssdev);
1255 	dsicm_disconnect(dssdev);
1256 
1257 	sysfs_remove_group(&pdev->dev.kobj, &dsicm_attr_group);
1258 
1259 	bldev = ddata->bldev;
1260 	if (bldev != NULL) {
1261 		bldev->props.power = FB_BLANK_POWERDOWN;
1262 		dsicm_bl_update_status(bldev);
1263 		backlight_device_unregister(bldev);
1264 	}
1265 
1266 	omap_dss_put_device(ddata->in);
1267 
1268 	dsicm_cancel_ulps_work(ddata);
1269 
1270 	/* reset, to be sure that the panel is in a valid state */
1271 	dsicm_hw_reset(ddata);
1272 
1273 	return 0;
1274 }
1275 
1276 static const struct of_device_id dsicm_of_match[] = {
1277 	{ .compatible = "omapdss,panel-dsi-cm", },
1278 	{},
1279 };
1280 
1281 MODULE_DEVICE_TABLE(of, dsicm_of_match);
1282 
1283 static struct platform_driver dsicm_driver = {
1284 	.probe = dsicm_probe,
1285 	.remove = __exit_p(dsicm_remove),
1286 	.driver = {
1287 		.name = "panel-dsi-cm",
1288 		.of_match_table = dsicm_of_match,
1289 		.suppress_bind_attrs = true,
1290 	},
1291 };
1292 
1293 module_platform_driver(dsicm_driver);
1294 
1295 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
1296 MODULE_DESCRIPTION("Generic DSI Command Mode Panel Driver");
1297 MODULE_LICENSE("GPL");
1298