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/fb.h>
14 #include <linux/gpio.h>
15 #include <linux/interrupt.h>
16 #include <linux/jiffies.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/sched/signal.h>
20 #include <linux/slab.h>
21 #include <linux/workqueue.h>
22 #include <linux/of_device.h>
23 #include <linux/of_gpio.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 	int reset_gpio;
57 	int 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 (gpio_is_valid(ddata->ext_te_gpio))
254 		disable_irq(gpio_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 (gpio_is_valid(ddata->ext_te_gpio))
296 		enable_irq(gpio_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 (gpio_is_valid(ddata->ext_te_gpio))
310 			enable_irq(gpio_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;
335 
336 	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
337 			dev->props.power == FB_BLANK_UNBLANK)
338 		level = dev->props.brightness;
339 	else
340 		level = 0;
341 
342 	dev_dbg(&ddata->pdev->dev, "update brightness to %d\n", level);
343 
344 	mutex_lock(&ddata->lock);
345 
346 	if (ddata->enabled) {
347 		in->ops.dsi->bus_lock(in);
348 
349 		r = dsicm_wake_up(ddata);
350 		if (!r)
351 			r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, level);
352 
353 		in->ops.dsi->bus_unlock(in);
354 	} else {
355 		r = 0;
356 	}
357 
358 	mutex_unlock(&ddata->lock);
359 
360 	return r;
361 }
362 
363 static int dsicm_bl_get_intensity(struct backlight_device *dev)
364 {
365 	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
366 			dev->props.power == FB_BLANK_UNBLANK)
367 		return dev->props.brightness;
368 
369 	return 0;
370 }
371 
372 static const struct backlight_ops dsicm_bl_ops = {
373 	.get_brightness = dsicm_bl_get_intensity,
374 	.update_status  = dsicm_bl_update_status,
375 };
376 
377 static void dsicm_get_resolution(struct omap_dss_device *dssdev,
378 		u16 *xres, u16 *yres)
379 {
380 	*xres = dssdev->panel.timings.x_res;
381 	*yres = dssdev->panel.timings.y_res;
382 }
383 
384 static ssize_t dsicm_num_errors_show(struct device *dev,
385 		struct device_attribute *attr, char *buf)
386 {
387 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
388 	struct omap_dss_device *in = ddata->in;
389 	u8 errors = 0;
390 	int r;
391 
392 	mutex_lock(&ddata->lock);
393 
394 	if (ddata->enabled) {
395 		in->ops.dsi->bus_lock(in);
396 
397 		r = dsicm_wake_up(ddata);
398 		if (!r)
399 			r = dsicm_dcs_read_1(ddata, DCS_READ_NUM_ERRORS,
400 					&errors);
401 
402 		in->ops.dsi->bus_unlock(in);
403 	} else {
404 		r = -ENODEV;
405 	}
406 
407 	mutex_unlock(&ddata->lock);
408 
409 	if (r)
410 		return r;
411 
412 	return sysfs_emit(buf, "%d\n", errors);
413 }
414 
415 static ssize_t dsicm_hw_revision_show(struct device *dev,
416 		struct device_attribute *attr, char *buf)
417 {
418 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
419 	struct omap_dss_device *in = ddata->in;
420 	u8 id1, id2, id3;
421 	int r;
422 
423 	mutex_lock(&ddata->lock);
424 
425 	if (ddata->enabled) {
426 		in->ops.dsi->bus_lock(in);
427 
428 		r = dsicm_wake_up(ddata);
429 		if (!r)
430 			r = dsicm_get_id(ddata, &id1, &id2, &id3);
431 
432 		in->ops.dsi->bus_unlock(in);
433 	} else {
434 		r = -ENODEV;
435 	}
436 
437 	mutex_unlock(&ddata->lock);
438 
439 	if (r)
440 		return r;
441 
442 	return sysfs_emit(buf, "%02x.%02x.%02x\n", id1, id2, id3);
443 }
444 
445 static ssize_t dsicm_store_ulps(struct device *dev,
446 		struct device_attribute *attr,
447 		const char *buf, size_t count)
448 {
449 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
450 	struct omap_dss_device *in = ddata->in;
451 	unsigned long t;
452 	int r;
453 
454 	r = kstrtoul(buf, 0, &t);
455 	if (r)
456 		return r;
457 
458 	mutex_lock(&ddata->lock);
459 
460 	if (ddata->enabled) {
461 		in->ops.dsi->bus_lock(in);
462 
463 		if (t)
464 			r = dsicm_enter_ulps(ddata);
465 		else
466 			r = dsicm_wake_up(ddata);
467 
468 		in->ops.dsi->bus_unlock(in);
469 	}
470 
471 	mutex_unlock(&ddata->lock);
472 
473 	if (r)
474 		return r;
475 
476 	return count;
477 }
478 
479 static ssize_t dsicm_show_ulps(struct device *dev,
480 		struct device_attribute *attr,
481 		char *buf)
482 {
483 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
484 	unsigned t;
485 
486 	mutex_lock(&ddata->lock);
487 	t = ddata->ulps_enabled;
488 	mutex_unlock(&ddata->lock);
489 
490 	return sysfs_emit(buf, "%u\n", t);
491 }
492 
493 static ssize_t dsicm_store_ulps_timeout(struct device *dev,
494 		struct device_attribute *attr,
495 		const char *buf, size_t count)
496 {
497 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
498 	struct omap_dss_device *in = ddata->in;
499 	unsigned long t;
500 	int r;
501 
502 	r = kstrtoul(buf, 0, &t);
503 	if (r)
504 		return r;
505 
506 	mutex_lock(&ddata->lock);
507 	ddata->ulps_timeout = t;
508 
509 	if (ddata->enabled) {
510 		/* dsicm_wake_up will restart the timer */
511 		in->ops.dsi->bus_lock(in);
512 		r = dsicm_wake_up(ddata);
513 		in->ops.dsi->bus_unlock(in);
514 	}
515 
516 	mutex_unlock(&ddata->lock);
517 
518 	if (r)
519 		return r;
520 
521 	return count;
522 }
523 
524 static ssize_t dsicm_show_ulps_timeout(struct device *dev,
525 		struct device_attribute *attr,
526 		char *buf)
527 {
528 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
529 	unsigned t;
530 
531 	mutex_lock(&ddata->lock);
532 	t = ddata->ulps_timeout;
533 	mutex_unlock(&ddata->lock);
534 
535 	return sysfs_emit(buf, "%u\n", t);
536 }
537 
538 static DEVICE_ATTR(num_dsi_errors, S_IRUGO, dsicm_num_errors_show, NULL);
539 static DEVICE_ATTR(hw_revision, S_IRUGO, dsicm_hw_revision_show, NULL);
540 static DEVICE_ATTR(ulps, S_IRUGO | S_IWUSR,
541 		dsicm_show_ulps, dsicm_store_ulps);
542 static DEVICE_ATTR(ulps_timeout, S_IRUGO | S_IWUSR,
543 		dsicm_show_ulps_timeout, dsicm_store_ulps_timeout);
544 
545 static struct attribute *dsicm_attrs[] = {
546 	&dev_attr_num_dsi_errors.attr,
547 	&dev_attr_hw_revision.attr,
548 	&dev_attr_ulps.attr,
549 	&dev_attr_ulps_timeout.attr,
550 	NULL,
551 };
552 
553 static const struct attribute_group dsicm_attr_group = {
554 	.attrs = dsicm_attrs,
555 };
556 
557 static void dsicm_hw_reset(struct panel_drv_data *ddata)
558 {
559 	if (!gpio_is_valid(ddata->reset_gpio))
560 		return;
561 
562 	gpio_set_value(ddata->reset_gpio, 1);
563 	udelay(10);
564 	/* reset the panel */
565 	gpio_set_value(ddata->reset_gpio, 0);
566 	/* assert reset */
567 	udelay(10);
568 	gpio_set_value(ddata->reset_gpio, 1);
569 	/* wait after releasing reset */
570 	usleep_range(5000, 10000);
571 }
572 
573 static int dsicm_power_on(struct panel_drv_data *ddata)
574 {
575 	struct omap_dss_device *in = ddata->in;
576 	u8 id1, id2, id3;
577 	int r;
578 	struct omap_dss_dsi_config dsi_config = {
579 		.mode = OMAP_DSS_DSI_CMD_MODE,
580 		.pixel_format = OMAP_DSS_DSI_FMT_RGB888,
581 		.timings = &ddata->timings,
582 		.hs_clk_min = 150000000,
583 		.hs_clk_max = 300000000,
584 		.lp_clk_min = 7000000,
585 		.lp_clk_max = 10000000,
586 	};
587 
588 	if (ddata->pin_config.num_pins > 0) {
589 		r = in->ops.dsi->configure_pins(in, &ddata->pin_config);
590 		if (r) {
591 			dev_err(&ddata->pdev->dev,
592 				"failed to configure DSI pins\n");
593 			goto err0;
594 		}
595 	}
596 
597 	r = in->ops.dsi->set_config(in, &dsi_config);
598 	if (r) {
599 		dev_err(&ddata->pdev->dev, "failed to configure DSI\n");
600 		goto err0;
601 	}
602 
603 	r = in->ops.dsi->enable(in);
604 	if (r) {
605 		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
606 		goto err0;
607 	}
608 
609 	dsicm_hw_reset(ddata);
610 
611 	in->ops.dsi->enable_hs(in, ddata->channel, false);
612 
613 	r = dsicm_sleep_out(ddata);
614 	if (r)
615 		goto err;
616 
617 	r = dsicm_get_id(ddata, &id1, &id2, &id3);
618 	if (r)
619 		goto err;
620 
621 	r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, 0xff);
622 	if (r)
623 		goto err;
624 
625 	r = dsicm_dcs_write_1(ddata, DCS_CTRL_DISPLAY,
626 			(1<<2) | (1<<5));	/* BL | BCTRL */
627 	if (r)
628 		goto err;
629 
630 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_PIXEL_FORMAT,
631 		MIPI_DCS_PIXEL_FMT_24BIT);
632 	if (r)
633 		goto err;
634 
635 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_ON);
636 	if (r)
637 		goto err;
638 
639 	r = _dsicm_enable_te(ddata, ddata->te_enabled);
640 	if (r)
641 		goto err;
642 
643 	r = in->ops.dsi->enable_video_output(in, ddata->channel);
644 	if (r)
645 		goto err;
646 
647 	ddata->enabled = 1;
648 
649 	if (!ddata->intro_printed) {
650 		dev_info(&ddata->pdev->dev, "panel revision %02x.%02x.%02x\n",
651 			id1, id2, id3);
652 		ddata->intro_printed = true;
653 	}
654 
655 	in->ops.dsi->enable_hs(in, ddata->channel, true);
656 
657 	return 0;
658 err:
659 	dev_err(&ddata->pdev->dev, "error while enabling panel, issuing HW reset\n");
660 
661 	dsicm_hw_reset(ddata);
662 
663 	in->ops.dsi->disable(in, true, false);
664 err0:
665 	return r;
666 }
667 
668 static void dsicm_power_off(struct panel_drv_data *ddata)
669 {
670 	struct omap_dss_device *in = ddata->in;
671 	int r;
672 
673 	in->ops.dsi->disable_video_output(in, ddata->channel);
674 
675 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_OFF);
676 	if (!r)
677 		r = dsicm_sleep_in(ddata);
678 
679 	if (r) {
680 		dev_err(&ddata->pdev->dev,
681 				"error disabling panel, issuing HW reset\n");
682 		dsicm_hw_reset(ddata);
683 	}
684 
685 	in->ops.dsi->disable(in, true, false);
686 
687 	ddata->enabled = 0;
688 }
689 
690 static int dsicm_panel_reset(struct panel_drv_data *ddata)
691 {
692 	dev_err(&ddata->pdev->dev, "performing LCD reset\n");
693 
694 	dsicm_power_off(ddata);
695 	dsicm_hw_reset(ddata);
696 	return dsicm_power_on(ddata);
697 }
698 
699 static int dsicm_connect(struct omap_dss_device *dssdev)
700 {
701 	struct panel_drv_data *ddata = to_panel_data(dssdev);
702 	struct omap_dss_device *in = ddata->in;
703 	struct device *dev = &ddata->pdev->dev;
704 	int r;
705 
706 	if (omapdss_device_is_connected(dssdev))
707 		return 0;
708 
709 	r = in->ops.dsi->connect(in, dssdev);
710 	if (r) {
711 		dev_err(dev, "Failed to connect to video source\n");
712 		return r;
713 	}
714 
715 	r = in->ops.dsi->request_vc(ddata->in, &ddata->channel);
716 	if (r) {
717 		dev_err(dev, "failed to get virtual channel\n");
718 		goto err_req_vc;
719 	}
720 
721 	r = in->ops.dsi->set_vc_id(ddata->in, ddata->channel, TCH);
722 	if (r) {
723 		dev_err(dev, "failed to set VC_ID\n");
724 		goto err_vc_id;
725 	}
726 
727 	return 0;
728 
729 err_vc_id:
730 	in->ops.dsi->release_vc(ddata->in, ddata->channel);
731 err_req_vc:
732 	in->ops.dsi->disconnect(in, dssdev);
733 	return r;
734 }
735 
736 static void dsicm_disconnect(struct omap_dss_device *dssdev)
737 {
738 	struct panel_drv_data *ddata = to_panel_data(dssdev);
739 	struct omap_dss_device *in = ddata->in;
740 
741 	if (!omapdss_device_is_connected(dssdev))
742 		return;
743 
744 	in->ops.dsi->release_vc(in, ddata->channel);
745 	in->ops.dsi->disconnect(in, dssdev);
746 }
747 
748 static int dsicm_enable(struct omap_dss_device *dssdev)
749 {
750 	struct panel_drv_data *ddata = to_panel_data(dssdev);
751 	struct omap_dss_device *in = ddata->in;
752 	int r;
753 
754 	dev_dbg(&ddata->pdev->dev, "enable\n");
755 
756 	mutex_lock(&ddata->lock);
757 
758 	if (!omapdss_device_is_connected(dssdev)) {
759 		r = -ENODEV;
760 		goto err;
761 	}
762 
763 	if (omapdss_device_is_enabled(dssdev)) {
764 		r = 0;
765 		goto err;
766 	}
767 
768 	in->ops.dsi->bus_lock(in);
769 
770 	r = dsicm_power_on(ddata);
771 
772 	in->ops.dsi->bus_unlock(in);
773 
774 	if (r)
775 		goto err;
776 
777 	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
778 
779 	mutex_unlock(&ddata->lock);
780 
781 	return 0;
782 err:
783 	dev_dbg(&ddata->pdev->dev, "enable failed\n");
784 	mutex_unlock(&ddata->lock);
785 	return r;
786 }
787 
788 static void dsicm_disable(struct omap_dss_device *dssdev)
789 {
790 	struct panel_drv_data *ddata = to_panel_data(dssdev);
791 	struct omap_dss_device *in = ddata->in;
792 	int r;
793 
794 	dev_dbg(&ddata->pdev->dev, "disable\n");
795 
796 	mutex_lock(&ddata->lock);
797 
798 	dsicm_cancel_ulps_work(ddata);
799 
800 	in->ops.dsi->bus_lock(in);
801 
802 	if (omapdss_device_is_enabled(dssdev)) {
803 		r = dsicm_wake_up(ddata);
804 		if (!r)
805 			dsicm_power_off(ddata);
806 	}
807 
808 	in->ops.dsi->bus_unlock(in);
809 
810 	dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
811 
812 	mutex_unlock(&ddata->lock);
813 }
814 
815 static void dsicm_framedone_cb(int err, void *data)
816 {
817 	struct panel_drv_data *ddata = data;
818 	struct omap_dss_device *in = ddata->in;
819 
820 	dev_dbg(&ddata->pdev->dev, "framedone, err %d\n", err);
821 	in->ops.dsi->bus_unlock(ddata->in);
822 }
823 
824 static irqreturn_t dsicm_te_isr(int irq, void *data)
825 {
826 	struct panel_drv_data *ddata = data;
827 	struct omap_dss_device *in = ddata->in;
828 	int old;
829 	int r;
830 
831 	old = atomic_cmpxchg(&ddata->do_update, 1, 0);
832 
833 	if (old) {
834 		cancel_delayed_work(&ddata->te_timeout_work);
835 
836 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
837 				ddata);
838 		if (r)
839 			goto err;
840 	}
841 
842 	return IRQ_HANDLED;
843 err:
844 	dev_err(&ddata->pdev->dev, "start update failed\n");
845 	in->ops.dsi->bus_unlock(in);
846 	return IRQ_HANDLED;
847 }
848 
849 static void dsicm_te_timeout_work_callback(struct work_struct *work)
850 {
851 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
852 					te_timeout_work.work);
853 	struct omap_dss_device *in = ddata->in;
854 
855 	dev_err(&ddata->pdev->dev, "TE not received for 250ms!\n");
856 
857 	atomic_set(&ddata->do_update, 0);
858 	in->ops.dsi->bus_unlock(in);
859 }
860 
861 static int dsicm_update(struct omap_dss_device *dssdev,
862 				    u16 x, u16 y, u16 w, u16 h)
863 {
864 	struct panel_drv_data *ddata = to_panel_data(dssdev);
865 	struct omap_dss_device *in = ddata->in;
866 	int r;
867 
868 	dev_dbg(&ddata->pdev->dev, "update %d, %d, %d x %d\n", x, y, w, h);
869 
870 	mutex_lock(&ddata->lock);
871 	in->ops.dsi->bus_lock(in);
872 
873 	r = dsicm_wake_up(ddata);
874 	if (r)
875 		goto err;
876 
877 	if (!ddata->enabled) {
878 		r = 0;
879 		goto err;
880 	}
881 
882 	/* XXX no need to send this every frame, but dsi break if not done */
883 	r = dsicm_set_update_window(ddata, 0, 0,
884 			dssdev->panel.timings.x_res,
885 			dssdev->panel.timings.y_res);
886 	if (r)
887 		goto err;
888 
889 	if (ddata->te_enabled && gpio_is_valid(ddata->ext_te_gpio)) {
890 		schedule_delayed_work(&ddata->te_timeout_work,
891 				msecs_to_jiffies(250));
892 		atomic_set(&ddata->do_update, 1);
893 	} else {
894 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
895 				ddata);
896 		if (r)
897 			goto err;
898 	}
899 
900 	/* note: no bus_unlock here. unlock is in framedone_cb */
901 	mutex_unlock(&ddata->lock);
902 	return 0;
903 err:
904 	in->ops.dsi->bus_unlock(in);
905 	mutex_unlock(&ddata->lock);
906 	return r;
907 }
908 
909 static int dsicm_sync(struct omap_dss_device *dssdev)
910 {
911 	struct panel_drv_data *ddata = to_panel_data(dssdev);
912 	struct omap_dss_device *in = ddata->in;
913 
914 	dev_dbg(&ddata->pdev->dev, "sync\n");
915 
916 	mutex_lock(&ddata->lock);
917 	in->ops.dsi->bus_lock(in);
918 	in->ops.dsi->bus_unlock(in);
919 	mutex_unlock(&ddata->lock);
920 
921 	dev_dbg(&ddata->pdev->dev, "sync done\n");
922 
923 	return 0;
924 }
925 
926 static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable)
927 {
928 	struct omap_dss_device *in = ddata->in;
929 	int r;
930 
931 	if (enable)
932 		r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_TEAR_ON, 0);
933 	else
934 		r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_TEAR_OFF);
935 
936 	if (!gpio_is_valid(ddata->ext_te_gpio))
937 		in->ops.dsi->enable_te(in, enable);
938 
939 	/* possible panel bug */
940 	msleep(100);
941 
942 	return r;
943 }
944 
945 static int dsicm_enable_te(struct omap_dss_device *dssdev, bool enable)
946 {
947 	struct panel_drv_data *ddata = to_panel_data(dssdev);
948 	struct omap_dss_device *in = ddata->in;
949 	int r;
950 
951 	mutex_lock(&ddata->lock);
952 
953 	if (ddata->te_enabled == enable)
954 		goto end;
955 
956 	in->ops.dsi->bus_lock(in);
957 
958 	if (ddata->enabled) {
959 		r = dsicm_wake_up(ddata);
960 		if (r)
961 			goto err;
962 
963 		r = _dsicm_enable_te(ddata, enable);
964 		if (r)
965 			goto err;
966 	}
967 
968 	ddata->te_enabled = enable;
969 
970 	in->ops.dsi->bus_unlock(in);
971 end:
972 	mutex_unlock(&ddata->lock);
973 
974 	return 0;
975 err:
976 	in->ops.dsi->bus_unlock(in);
977 	mutex_unlock(&ddata->lock);
978 
979 	return r;
980 }
981 
982 static int dsicm_get_te(struct omap_dss_device *dssdev)
983 {
984 	struct panel_drv_data *ddata = to_panel_data(dssdev);
985 	int r;
986 
987 	mutex_lock(&ddata->lock);
988 	r = ddata->te_enabled;
989 	mutex_unlock(&ddata->lock);
990 
991 	return r;
992 }
993 
994 static int dsicm_memory_read(struct omap_dss_device *dssdev,
995 		void *buf, size_t size,
996 		u16 x, u16 y, u16 w, u16 h)
997 {
998 	struct panel_drv_data *ddata = to_panel_data(dssdev);
999 	struct omap_dss_device *in = ddata->in;
1000 	int r;
1001 	int first = 1;
1002 	int plen;
1003 	unsigned buf_used = 0;
1004 
1005 	if (size < w * h * 3)
1006 		return -ENOMEM;
1007 
1008 	mutex_lock(&ddata->lock);
1009 
1010 	if (!ddata->enabled) {
1011 		r = -ENODEV;
1012 		goto err1;
1013 	}
1014 
1015 	size = min(w * h * 3,
1016 			dssdev->panel.timings.x_res *
1017 			dssdev->panel.timings.y_res * 3);
1018 
1019 	in->ops.dsi->bus_lock(in);
1020 
1021 	r = dsicm_wake_up(ddata);
1022 	if (r)
1023 		goto err2;
1024 
1025 	/* plen 1 or 2 goes into short packet. until checksum error is fixed,
1026 	 * use short packets. plen 32 works, but bigger packets seem to cause
1027 	 * an error. */
1028 	if (size % 2)
1029 		plen = 1;
1030 	else
1031 		plen = 2;
1032 
1033 	dsicm_set_update_window(ddata, x, y, w, h);
1034 
1035 	r = in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, plen);
1036 	if (r)
1037 		goto err2;
1038 
1039 	while (buf_used < size) {
1040 		u8 dcs_cmd = first ? 0x2e : 0x3e;
1041 		first = 0;
1042 
1043 		r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd,
1044 				buf + buf_used, size - buf_used);
1045 
1046 		if (r < 0) {
1047 			dev_err(dssdev->dev, "read error\n");
1048 			goto err3;
1049 		}
1050 
1051 		buf_used += r;
1052 
1053 		if (r < plen) {
1054 			dev_err(&ddata->pdev->dev, "short read\n");
1055 			break;
1056 		}
1057 
1058 		if (signal_pending(current)) {
1059 			dev_err(&ddata->pdev->dev, "signal pending, "
1060 					"aborting memory read\n");
1061 			r = -ERESTARTSYS;
1062 			goto err3;
1063 		}
1064 	}
1065 
1066 	r = buf_used;
1067 
1068 err3:
1069 	in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, 1);
1070 err2:
1071 	in->ops.dsi->bus_unlock(in);
1072 err1:
1073 	mutex_unlock(&ddata->lock);
1074 	return r;
1075 }
1076 
1077 static void dsicm_ulps_work(struct work_struct *work)
1078 {
1079 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
1080 			ulps_work.work);
1081 	struct omap_dss_device *dssdev = &ddata->dssdev;
1082 	struct omap_dss_device *in = ddata->in;
1083 
1084 	mutex_lock(&ddata->lock);
1085 
1086 	if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE || !ddata->enabled) {
1087 		mutex_unlock(&ddata->lock);
1088 		return;
1089 	}
1090 
1091 	in->ops.dsi->bus_lock(in);
1092 
1093 	dsicm_enter_ulps(ddata);
1094 
1095 	in->ops.dsi->bus_unlock(in);
1096 	mutex_unlock(&ddata->lock);
1097 }
1098 
1099 static struct omap_dss_driver dsicm_ops = {
1100 	.connect	= dsicm_connect,
1101 	.disconnect	= dsicm_disconnect,
1102 
1103 	.enable		= dsicm_enable,
1104 	.disable	= dsicm_disable,
1105 
1106 	.update		= dsicm_update,
1107 	.sync		= dsicm_sync,
1108 
1109 	.get_resolution	= dsicm_get_resolution,
1110 	.get_recommended_bpp = omapdss_default_get_recommended_bpp,
1111 
1112 	.enable_te	= dsicm_enable_te,
1113 	.get_te		= dsicm_get_te,
1114 
1115 	.memory_read	= dsicm_memory_read,
1116 };
1117 
1118 static int dsicm_probe_of(struct platform_device *pdev)
1119 {
1120 	struct device_node *node = pdev->dev.of_node;
1121 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
1122 	struct omap_dss_device *in;
1123 	int gpio;
1124 
1125 	gpio = of_get_named_gpio(node, "reset-gpios", 0);
1126 	if (!gpio_is_valid(gpio)) {
1127 		dev_err(&pdev->dev, "failed to parse reset gpio\n");
1128 		return gpio;
1129 	}
1130 	ddata->reset_gpio = gpio;
1131 
1132 	gpio = of_get_named_gpio(node, "te-gpios", 0);
1133 	if (gpio_is_valid(gpio) || gpio == -ENOENT) {
1134 		ddata->ext_te_gpio = gpio;
1135 	} else {
1136 		dev_err(&pdev->dev, "failed to parse TE gpio\n");
1137 		return gpio;
1138 	}
1139 
1140 	in = omapdss_of_find_source_for_first_ep(node);
1141 	if (IS_ERR(in)) {
1142 		dev_err(&pdev->dev, "failed to find video source\n");
1143 		return PTR_ERR(in);
1144 	}
1145 
1146 	ddata->in = in;
1147 
1148 	/* TODO: ulps, backlight */
1149 
1150 	return 0;
1151 }
1152 
1153 static int dsicm_probe(struct platform_device *pdev)
1154 {
1155 	struct backlight_properties props;
1156 	struct panel_drv_data *ddata;
1157 	struct backlight_device *bldev = NULL;
1158 	struct device *dev = &pdev->dev;
1159 	struct omap_dss_device *dssdev;
1160 	int r;
1161 
1162 	dev_dbg(dev, "probe\n");
1163 
1164 	if (!pdev->dev.of_node)
1165 		return -ENODEV;
1166 
1167 	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
1168 	if (!ddata)
1169 		return -ENOMEM;
1170 
1171 	platform_set_drvdata(pdev, ddata);
1172 	ddata->pdev = pdev;
1173 
1174 	r = dsicm_probe_of(pdev);
1175 	if (r)
1176 		return r;
1177 
1178 	ddata->timings.x_res = 864;
1179 	ddata->timings.y_res = 480;
1180 	ddata->timings.pixelclock = 864 * 480 * 60;
1181 
1182 	dssdev = &ddata->dssdev;
1183 	dssdev->dev = dev;
1184 	dssdev->driver = &dsicm_ops;
1185 	dssdev->panel.timings = ddata->timings;
1186 	dssdev->type = OMAP_DISPLAY_TYPE_DSI;
1187 	dssdev->owner = THIS_MODULE;
1188 
1189 	dssdev->panel.dsi_pix_fmt = OMAP_DSS_DSI_FMT_RGB888;
1190 	dssdev->caps = OMAP_DSS_DISPLAY_CAP_MANUAL_UPDATE |
1191 		OMAP_DSS_DISPLAY_CAP_TEAR_ELIM;
1192 
1193 	r = omapdss_register_display(dssdev);
1194 	if (r) {
1195 		dev_err(dev, "Failed to register panel\n");
1196 		goto err_reg;
1197 	}
1198 
1199 	mutex_init(&ddata->lock);
1200 
1201 	atomic_set(&ddata->do_update, 0);
1202 
1203 	if (gpio_is_valid(ddata->reset_gpio)) {
1204 		r = devm_gpio_request_one(dev, ddata->reset_gpio,
1205 				GPIOF_OUT_INIT_LOW, "taal rst");
1206 		if (r) {
1207 			dev_err(dev, "failed to request reset gpio\n");
1208 			return r;
1209 		}
1210 	}
1211 
1212 	if (gpio_is_valid(ddata->ext_te_gpio)) {
1213 		r = devm_gpio_request_one(dev, ddata->ext_te_gpio,
1214 				GPIOF_IN, "taal irq");
1215 		if (r) {
1216 			dev_err(dev, "GPIO request failed\n");
1217 			return r;
1218 		}
1219 
1220 		r = devm_request_irq(dev, gpio_to_irq(ddata->ext_te_gpio),
1221 				dsicm_te_isr,
1222 				IRQF_TRIGGER_RISING,
1223 				"taal vsync", ddata);
1224 
1225 		if (r) {
1226 			dev_err(dev, "IRQ request failed\n");
1227 			return r;
1228 		}
1229 
1230 		INIT_DEFERRABLE_WORK(&ddata->te_timeout_work,
1231 					dsicm_te_timeout_work_callback);
1232 
1233 		dev_dbg(dev, "Using GPIO TE\n");
1234 	}
1235 
1236 	INIT_DELAYED_WORK(&ddata->ulps_work, dsicm_ulps_work);
1237 
1238 	dsicm_hw_reset(ddata);
1239 
1240 	if (ddata->use_dsi_backlight) {
1241 		memset(&props, 0, sizeof(struct backlight_properties));
1242 		props.max_brightness = 255;
1243 
1244 		props.type = BACKLIGHT_RAW;
1245 		bldev = backlight_device_register(dev_name(dev),
1246 				dev, ddata, &dsicm_bl_ops, &props);
1247 		if (IS_ERR(bldev)) {
1248 			r = PTR_ERR(bldev);
1249 			goto err_reg;
1250 		}
1251 
1252 		ddata->bldev = bldev;
1253 
1254 		bldev->props.fb_blank = FB_BLANK_UNBLANK;
1255 		bldev->props.power = FB_BLANK_UNBLANK;
1256 		bldev->props.brightness = 255;
1257 
1258 		dsicm_bl_update_status(bldev);
1259 	}
1260 
1261 	r = sysfs_create_group(&dev->kobj, &dsicm_attr_group);
1262 	if (r) {
1263 		dev_err(dev, "failed to create sysfs files\n");
1264 		goto err_sysfs_create;
1265 	}
1266 
1267 	return 0;
1268 
1269 err_sysfs_create:
1270 	if (bldev != NULL)
1271 		backlight_device_unregister(bldev);
1272 err_reg:
1273 	return r;
1274 }
1275 
1276 static int __exit dsicm_remove(struct platform_device *pdev)
1277 {
1278 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
1279 	struct omap_dss_device *dssdev = &ddata->dssdev;
1280 	struct backlight_device *bldev;
1281 
1282 	dev_dbg(&pdev->dev, "remove\n");
1283 
1284 	omapdss_unregister_display(dssdev);
1285 
1286 	dsicm_disable(dssdev);
1287 	dsicm_disconnect(dssdev);
1288 
1289 	sysfs_remove_group(&pdev->dev.kobj, &dsicm_attr_group);
1290 
1291 	bldev = ddata->bldev;
1292 	if (bldev != NULL) {
1293 		bldev->props.power = FB_BLANK_POWERDOWN;
1294 		dsicm_bl_update_status(bldev);
1295 		backlight_device_unregister(bldev);
1296 	}
1297 
1298 	omap_dss_put_device(ddata->in);
1299 
1300 	dsicm_cancel_ulps_work(ddata);
1301 
1302 	/* reset, to be sure that the panel is in a valid state */
1303 	dsicm_hw_reset(ddata);
1304 
1305 	return 0;
1306 }
1307 
1308 static const struct of_device_id dsicm_of_match[] = {
1309 	{ .compatible = "omapdss,panel-dsi-cm", },
1310 	{},
1311 };
1312 
1313 MODULE_DEVICE_TABLE(of, dsicm_of_match);
1314 
1315 static struct platform_driver dsicm_driver = {
1316 	.probe = dsicm_probe,
1317 	.remove = __exit_p(dsicm_remove),
1318 	.driver = {
1319 		.name = "panel-dsi-cm",
1320 		.of_match_table = dsicm_of_match,
1321 		.suppress_bind_attrs = true,
1322 	},
1323 };
1324 
1325 module_platform_driver(dsicm_driver);
1326 
1327 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
1328 MODULE_DESCRIPTION("Generic DSI Command Mode Panel Driver");
1329 MODULE_LICENSE("GPL");
1330