xref: /linux/drivers/video/fbdev/omap2/omapfb/displays/panel-dsi-cm.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 	return backlight_get_brightness(dev);
360 }
361 
362 static const struct backlight_ops dsicm_bl_ops = {
363 	.get_brightness = dsicm_bl_get_intensity,
364 	.update_status  = dsicm_bl_update_status,
365 };
366 
367 static void dsicm_get_resolution(struct omap_dss_device *dssdev,
368 		u16 *xres, u16 *yres)
369 {
370 	*xres = dssdev->panel.timings.x_res;
371 	*yres = dssdev->panel.timings.y_res;
372 }
373 
374 static ssize_t dsicm_num_errors_show(struct device *dev,
375 		struct device_attribute *attr, char *buf)
376 {
377 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
378 	struct omap_dss_device *in = ddata->in;
379 	u8 errors = 0;
380 	int r;
381 
382 	mutex_lock(&ddata->lock);
383 
384 	if (ddata->enabled) {
385 		in->ops.dsi->bus_lock(in);
386 
387 		r = dsicm_wake_up(ddata);
388 		if (!r)
389 			r = dsicm_dcs_read_1(ddata, DCS_READ_NUM_ERRORS,
390 					&errors);
391 
392 		in->ops.dsi->bus_unlock(in);
393 	} else {
394 		r = -ENODEV;
395 	}
396 
397 	mutex_unlock(&ddata->lock);
398 
399 	if (r)
400 		return r;
401 
402 	return sysfs_emit(buf, "%d\n", errors);
403 }
404 
405 static ssize_t dsicm_hw_revision_show(struct device *dev,
406 		struct device_attribute *attr, char *buf)
407 {
408 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
409 	struct omap_dss_device *in = ddata->in;
410 	u8 id1, id2, id3;
411 	int r;
412 
413 	mutex_lock(&ddata->lock);
414 
415 	if (ddata->enabled) {
416 		in->ops.dsi->bus_lock(in);
417 
418 		r = dsicm_wake_up(ddata);
419 		if (!r)
420 			r = dsicm_get_id(ddata, &id1, &id2, &id3);
421 
422 		in->ops.dsi->bus_unlock(in);
423 	} else {
424 		r = -ENODEV;
425 	}
426 
427 	mutex_unlock(&ddata->lock);
428 
429 	if (r)
430 		return r;
431 
432 	return sysfs_emit(buf, "%02x.%02x.%02x\n", id1, id2, id3);
433 }
434 
435 static ssize_t dsicm_store_ulps(struct device *dev,
436 		struct device_attribute *attr,
437 		const char *buf, size_t count)
438 {
439 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
440 	struct omap_dss_device *in = ddata->in;
441 	unsigned long t;
442 	int r;
443 
444 	r = kstrtoul(buf, 0, &t);
445 	if (r)
446 		return r;
447 
448 	mutex_lock(&ddata->lock);
449 
450 	if (ddata->enabled) {
451 		in->ops.dsi->bus_lock(in);
452 
453 		if (t)
454 			r = dsicm_enter_ulps(ddata);
455 		else
456 			r = dsicm_wake_up(ddata);
457 
458 		in->ops.dsi->bus_unlock(in);
459 	}
460 
461 	mutex_unlock(&ddata->lock);
462 
463 	if (r)
464 		return r;
465 
466 	return count;
467 }
468 
469 static ssize_t dsicm_show_ulps(struct device *dev,
470 		struct device_attribute *attr,
471 		char *buf)
472 {
473 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
474 	unsigned t;
475 
476 	mutex_lock(&ddata->lock);
477 	t = ddata->ulps_enabled;
478 	mutex_unlock(&ddata->lock);
479 
480 	return sysfs_emit(buf, "%u\n", t);
481 }
482 
483 static ssize_t dsicm_store_ulps_timeout(struct device *dev,
484 		struct device_attribute *attr,
485 		const char *buf, size_t count)
486 {
487 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
488 	struct omap_dss_device *in = ddata->in;
489 	unsigned long t;
490 	int r;
491 
492 	r = kstrtoul(buf, 0, &t);
493 	if (r)
494 		return r;
495 
496 	mutex_lock(&ddata->lock);
497 	ddata->ulps_timeout = t;
498 
499 	if (ddata->enabled) {
500 		/* dsicm_wake_up will restart the timer */
501 		in->ops.dsi->bus_lock(in);
502 		r = dsicm_wake_up(ddata);
503 		in->ops.dsi->bus_unlock(in);
504 	}
505 
506 	mutex_unlock(&ddata->lock);
507 
508 	if (r)
509 		return r;
510 
511 	return count;
512 }
513 
514 static ssize_t dsicm_show_ulps_timeout(struct device *dev,
515 		struct device_attribute *attr,
516 		char *buf)
517 {
518 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
519 	unsigned t;
520 
521 	mutex_lock(&ddata->lock);
522 	t = ddata->ulps_timeout;
523 	mutex_unlock(&ddata->lock);
524 
525 	return sysfs_emit(buf, "%u\n", t);
526 }
527 
528 static DEVICE_ATTR(num_dsi_errors, S_IRUGO, dsicm_num_errors_show, NULL);
529 static DEVICE_ATTR(hw_revision, S_IRUGO, dsicm_hw_revision_show, NULL);
530 static DEVICE_ATTR(ulps, S_IRUGO | S_IWUSR,
531 		dsicm_show_ulps, dsicm_store_ulps);
532 static DEVICE_ATTR(ulps_timeout, S_IRUGO | S_IWUSR,
533 		dsicm_show_ulps_timeout, dsicm_store_ulps_timeout);
534 
535 static struct attribute *dsicm_attrs[] = {
536 	&dev_attr_num_dsi_errors.attr,
537 	&dev_attr_hw_revision.attr,
538 	&dev_attr_ulps.attr,
539 	&dev_attr_ulps_timeout.attr,
540 	NULL,
541 };
542 
543 static const struct attribute_group dsicm_attr_group = {
544 	.attrs = dsicm_attrs,
545 };
546 
547 static void dsicm_hw_reset(struct panel_drv_data *ddata)
548 {
549 	/*
550 	 * Note that we appear to activate the reset line here. However
551 	 * existing DTSes specified incorrect polarity for it (active high),
552 	 * so in fact this deasserts the reset line.
553 	 */
554 	gpiod_set_value_cansleep(ddata->reset_gpio, 1);
555 	udelay(10);
556 	/* reset the panel */
557 	gpiod_set_value_cansleep(ddata->reset_gpio, 0);
558 	/* keep reset asserted */
559 	udelay(10);
560 	/* release reset line */
561 	gpiod_set_value_cansleep(ddata->reset_gpio, 1);
562 	/* wait after releasing reset */
563 	usleep_range(5000, 10000);
564 }
565 
566 static int dsicm_power_on(struct panel_drv_data *ddata)
567 {
568 	struct omap_dss_device *in = ddata->in;
569 	u8 id1, id2, id3;
570 	int r;
571 	struct omap_dss_dsi_config dsi_config = {
572 		.mode = OMAP_DSS_DSI_CMD_MODE,
573 		.pixel_format = OMAP_DSS_DSI_FMT_RGB888,
574 		.timings = &ddata->timings,
575 		.hs_clk_min = 150000000,
576 		.hs_clk_max = 300000000,
577 		.lp_clk_min = 7000000,
578 		.lp_clk_max = 10000000,
579 	};
580 
581 	if (ddata->pin_config.num_pins > 0) {
582 		r = in->ops.dsi->configure_pins(in, &ddata->pin_config);
583 		if (r) {
584 			dev_err(&ddata->pdev->dev,
585 				"failed to configure DSI pins\n");
586 			goto err0;
587 		}
588 	}
589 
590 	r = in->ops.dsi->set_config(in, &dsi_config);
591 	if (r) {
592 		dev_err(&ddata->pdev->dev, "failed to configure DSI\n");
593 		goto err0;
594 	}
595 
596 	r = in->ops.dsi->enable(in);
597 	if (r) {
598 		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
599 		goto err0;
600 	}
601 
602 	dsicm_hw_reset(ddata);
603 
604 	in->ops.dsi->enable_hs(in, ddata->channel, false);
605 
606 	r = dsicm_sleep_out(ddata);
607 	if (r)
608 		goto err;
609 
610 	r = dsicm_get_id(ddata, &id1, &id2, &id3);
611 	if (r)
612 		goto err;
613 
614 	r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, 0xff);
615 	if (r)
616 		goto err;
617 
618 	r = dsicm_dcs_write_1(ddata, DCS_CTRL_DISPLAY,
619 			(1<<2) | (1<<5));	/* BL | BCTRL */
620 	if (r)
621 		goto err;
622 
623 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_PIXEL_FORMAT,
624 		MIPI_DCS_PIXEL_FMT_24BIT);
625 	if (r)
626 		goto err;
627 
628 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_ON);
629 	if (r)
630 		goto err;
631 
632 	r = _dsicm_enable_te(ddata, ddata->te_enabled);
633 	if (r)
634 		goto err;
635 
636 	r = in->ops.dsi->enable_video_output(in, ddata->channel);
637 	if (r)
638 		goto err;
639 
640 	ddata->enabled = 1;
641 
642 	if (!ddata->intro_printed) {
643 		dev_info(&ddata->pdev->dev, "panel revision %02x.%02x.%02x\n",
644 			id1, id2, id3);
645 		ddata->intro_printed = true;
646 	}
647 
648 	in->ops.dsi->enable_hs(in, ddata->channel, true);
649 
650 	return 0;
651 err:
652 	dev_err(&ddata->pdev->dev, "error while enabling panel, issuing HW reset\n");
653 
654 	dsicm_hw_reset(ddata);
655 
656 	in->ops.dsi->disable(in, true, false);
657 err0:
658 	return r;
659 }
660 
661 static void dsicm_power_off(struct panel_drv_data *ddata)
662 {
663 	struct omap_dss_device *in = ddata->in;
664 	int r;
665 
666 	in->ops.dsi->disable_video_output(in, ddata->channel);
667 
668 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_OFF);
669 	if (!r)
670 		r = dsicm_sleep_in(ddata);
671 
672 	if (r) {
673 		dev_err(&ddata->pdev->dev,
674 				"error disabling panel, issuing HW reset\n");
675 		dsicm_hw_reset(ddata);
676 	}
677 
678 	in->ops.dsi->disable(in, true, false);
679 
680 	ddata->enabled = 0;
681 }
682 
683 static int dsicm_panel_reset(struct panel_drv_data *ddata)
684 {
685 	dev_err(&ddata->pdev->dev, "performing LCD reset\n");
686 
687 	dsicm_power_off(ddata);
688 	dsicm_hw_reset(ddata);
689 	return dsicm_power_on(ddata);
690 }
691 
692 static int dsicm_connect(struct omap_dss_device *dssdev)
693 {
694 	struct panel_drv_data *ddata = to_panel_data(dssdev);
695 	struct omap_dss_device *in = ddata->in;
696 	struct device *dev = &ddata->pdev->dev;
697 	int r;
698 
699 	if (omapdss_device_is_connected(dssdev))
700 		return 0;
701 
702 	r = in->ops.dsi->connect(in, dssdev);
703 	if (r) {
704 		dev_err(dev, "Failed to connect to video source\n");
705 		return r;
706 	}
707 
708 	r = in->ops.dsi->request_vc(ddata->in, &ddata->channel);
709 	if (r) {
710 		dev_err(dev, "failed to get virtual channel\n");
711 		goto err_req_vc;
712 	}
713 
714 	r = in->ops.dsi->set_vc_id(ddata->in, ddata->channel, TCH);
715 	if (r) {
716 		dev_err(dev, "failed to set VC_ID\n");
717 		goto err_vc_id;
718 	}
719 
720 	return 0;
721 
722 err_vc_id:
723 	in->ops.dsi->release_vc(ddata->in, ddata->channel);
724 err_req_vc:
725 	in->ops.dsi->disconnect(in, dssdev);
726 	return r;
727 }
728 
729 static void dsicm_disconnect(struct omap_dss_device *dssdev)
730 {
731 	struct panel_drv_data *ddata = to_panel_data(dssdev);
732 	struct omap_dss_device *in = ddata->in;
733 
734 	if (!omapdss_device_is_connected(dssdev))
735 		return;
736 
737 	in->ops.dsi->release_vc(in, ddata->channel);
738 	in->ops.dsi->disconnect(in, dssdev);
739 }
740 
741 static int dsicm_enable(struct omap_dss_device *dssdev)
742 {
743 	struct panel_drv_data *ddata = to_panel_data(dssdev);
744 	struct omap_dss_device *in = ddata->in;
745 	int r;
746 
747 	dev_dbg(&ddata->pdev->dev, "enable\n");
748 
749 	mutex_lock(&ddata->lock);
750 
751 	if (!omapdss_device_is_connected(dssdev)) {
752 		r = -ENODEV;
753 		goto err;
754 	}
755 
756 	if (omapdss_device_is_enabled(dssdev)) {
757 		r = 0;
758 		goto err;
759 	}
760 
761 	in->ops.dsi->bus_lock(in);
762 
763 	r = dsicm_power_on(ddata);
764 
765 	in->ops.dsi->bus_unlock(in);
766 
767 	if (r)
768 		goto err;
769 
770 	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
771 
772 	mutex_unlock(&ddata->lock);
773 
774 	return 0;
775 err:
776 	dev_dbg(&ddata->pdev->dev, "enable failed\n");
777 	mutex_unlock(&ddata->lock);
778 	return r;
779 }
780 
781 static void dsicm_disable(struct omap_dss_device *dssdev)
782 {
783 	struct panel_drv_data *ddata = to_panel_data(dssdev);
784 	struct omap_dss_device *in = ddata->in;
785 	int r;
786 
787 	dev_dbg(&ddata->pdev->dev, "disable\n");
788 
789 	mutex_lock(&ddata->lock);
790 
791 	dsicm_cancel_ulps_work(ddata);
792 
793 	in->ops.dsi->bus_lock(in);
794 
795 	if (omapdss_device_is_enabled(dssdev)) {
796 		r = dsicm_wake_up(ddata);
797 		if (!r)
798 			dsicm_power_off(ddata);
799 	}
800 
801 	in->ops.dsi->bus_unlock(in);
802 
803 	dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
804 
805 	mutex_unlock(&ddata->lock);
806 }
807 
808 static void dsicm_framedone_cb(int err, void *data)
809 {
810 	struct panel_drv_data *ddata = data;
811 	struct omap_dss_device *in = ddata->in;
812 
813 	dev_dbg(&ddata->pdev->dev, "framedone, err %d\n", err);
814 	in->ops.dsi->bus_unlock(ddata->in);
815 }
816 
817 static irqreturn_t dsicm_te_isr(int irq, void *data)
818 {
819 	struct panel_drv_data *ddata = data;
820 	struct omap_dss_device *in = ddata->in;
821 	int old;
822 	int r;
823 
824 	old = atomic_cmpxchg(&ddata->do_update, 1, 0);
825 
826 	if (old) {
827 		cancel_delayed_work(&ddata->te_timeout_work);
828 
829 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
830 				ddata);
831 		if (r)
832 			goto err;
833 	}
834 
835 	return IRQ_HANDLED;
836 err:
837 	dev_err(&ddata->pdev->dev, "start update failed\n");
838 	in->ops.dsi->bus_unlock(in);
839 	return IRQ_HANDLED;
840 }
841 
842 static void dsicm_te_timeout_work_callback(struct work_struct *work)
843 {
844 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
845 					te_timeout_work.work);
846 	struct omap_dss_device *in = ddata->in;
847 
848 	dev_err(&ddata->pdev->dev, "TE not received for 250ms!\n");
849 
850 	atomic_set(&ddata->do_update, 0);
851 	in->ops.dsi->bus_unlock(in);
852 }
853 
854 static int dsicm_update(struct omap_dss_device *dssdev,
855 				    u16 x, u16 y, u16 w, u16 h)
856 {
857 	struct panel_drv_data *ddata = to_panel_data(dssdev);
858 	struct omap_dss_device *in = ddata->in;
859 	int r;
860 
861 	dev_dbg(&ddata->pdev->dev, "update %d, %d, %d x %d\n", x, y, w, h);
862 
863 	mutex_lock(&ddata->lock);
864 	in->ops.dsi->bus_lock(in);
865 
866 	r = dsicm_wake_up(ddata);
867 	if (r)
868 		goto err;
869 
870 	if (!ddata->enabled) {
871 		r = 0;
872 		goto err;
873 	}
874 
875 	/* XXX no need to send this every frame, but dsi break if not done */
876 	r = dsicm_set_update_window(ddata, 0, 0,
877 			dssdev->panel.timings.x_res,
878 			dssdev->panel.timings.y_res);
879 	if (r)
880 		goto err;
881 
882 	if (ddata->te_enabled && ddata->ext_te_gpio) {
883 		schedule_delayed_work(&ddata->te_timeout_work,
884 				msecs_to_jiffies(250));
885 		atomic_set(&ddata->do_update, 1);
886 	} else {
887 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
888 				ddata);
889 		if (r)
890 			goto err;
891 	}
892 
893 	/* note: no bus_unlock here. unlock is in framedone_cb */
894 	mutex_unlock(&ddata->lock);
895 	return 0;
896 err:
897 	in->ops.dsi->bus_unlock(in);
898 	mutex_unlock(&ddata->lock);
899 	return r;
900 }
901 
902 static int dsicm_sync(struct omap_dss_device *dssdev)
903 {
904 	struct panel_drv_data *ddata = to_panel_data(dssdev);
905 	struct omap_dss_device *in = ddata->in;
906 
907 	dev_dbg(&ddata->pdev->dev, "sync\n");
908 
909 	mutex_lock(&ddata->lock);
910 	in->ops.dsi->bus_lock(in);
911 	in->ops.dsi->bus_unlock(in);
912 	mutex_unlock(&ddata->lock);
913 
914 	dev_dbg(&ddata->pdev->dev, "sync done\n");
915 
916 	return 0;
917 }
918 
919 static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable)
920 {
921 	struct omap_dss_device *in = ddata->in;
922 	int r;
923 
924 	if (enable)
925 		r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_TEAR_ON, 0);
926 	else
927 		r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_TEAR_OFF);
928 
929 	if (!ddata->ext_te_gpio)
930 		in->ops.dsi->enable_te(in, enable);
931 
932 	/* possible panel bug */
933 	msleep(100);
934 
935 	return r;
936 }
937 
938 static int dsicm_enable_te(struct omap_dss_device *dssdev, bool enable)
939 {
940 	struct panel_drv_data *ddata = to_panel_data(dssdev);
941 	struct omap_dss_device *in = ddata->in;
942 	int r;
943 
944 	mutex_lock(&ddata->lock);
945 
946 	if (ddata->te_enabled == enable)
947 		goto end;
948 
949 	in->ops.dsi->bus_lock(in);
950 
951 	if (ddata->enabled) {
952 		r = dsicm_wake_up(ddata);
953 		if (r)
954 			goto err;
955 
956 		r = _dsicm_enable_te(ddata, enable);
957 		if (r)
958 			goto err;
959 	}
960 
961 	ddata->te_enabled = enable;
962 
963 	in->ops.dsi->bus_unlock(in);
964 end:
965 	mutex_unlock(&ddata->lock);
966 
967 	return 0;
968 err:
969 	in->ops.dsi->bus_unlock(in);
970 	mutex_unlock(&ddata->lock);
971 
972 	return r;
973 }
974 
975 static int dsicm_get_te(struct omap_dss_device *dssdev)
976 {
977 	struct panel_drv_data *ddata = to_panel_data(dssdev);
978 	int r;
979 
980 	mutex_lock(&ddata->lock);
981 	r = ddata->te_enabled;
982 	mutex_unlock(&ddata->lock);
983 
984 	return r;
985 }
986 
987 static int dsicm_memory_read(struct omap_dss_device *dssdev,
988 		void *buf, size_t size,
989 		u16 x, u16 y, u16 w, u16 h)
990 {
991 	struct panel_drv_data *ddata = to_panel_data(dssdev);
992 	struct omap_dss_device *in = ddata->in;
993 	int r;
994 	int first = 1;
995 	int plen;
996 	unsigned buf_used = 0;
997 
998 	if (size < w * h * 3)
999 		return -ENOMEM;
1000 
1001 	mutex_lock(&ddata->lock);
1002 
1003 	if (!ddata->enabled) {
1004 		r = -ENODEV;
1005 		goto err1;
1006 	}
1007 
1008 	size = min(w * h * 3,
1009 			dssdev->panel.timings.x_res *
1010 			dssdev->panel.timings.y_res * 3);
1011 
1012 	in->ops.dsi->bus_lock(in);
1013 
1014 	r = dsicm_wake_up(ddata);
1015 	if (r)
1016 		goto err2;
1017 
1018 	/* plen 1 or 2 goes into short packet. until checksum error is fixed,
1019 	 * use short packets. plen 32 works, but bigger packets seem to cause
1020 	 * an error. */
1021 	if (size % 2)
1022 		plen = 1;
1023 	else
1024 		plen = 2;
1025 
1026 	dsicm_set_update_window(ddata, x, y, w, h);
1027 
1028 	r = in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, plen);
1029 	if (r)
1030 		goto err2;
1031 
1032 	while (buf_used < size) {
1033 		u8 dcs_cmd = first ? 0x2e : 0x3e;
1034 		first = 0;
1035 
1036 		r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd,
1037 				buf + buf_used, size - buf_used);
1038 
1039 		if (r < 0) {
1040 			dev_err(dssdev->dev, "read error\n");
1041 			goto err3;
1042 		}
1043 
1044 		buf_used += r;
1045 
1046 		if (r < plen) {
1047 			dev_err(&ddata->pdev->dev, "short read\n");
1048 			break;
1049 		}
1050 
1051 		if (signal_pending(current)) {
1052 			dev_err(&ddata->pdev->dev, "signal pending, "
1053 					"aborting memory read\n");
1054 			r = -ERESTARTSYS;
1055 			goto err3;
1056 		}
1057 	}
1058 
1059 	r = buf_used;
1060 
1061 err3:
1062 	in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, 1);
1063 err2:
1064 	in->ops.dsi->bus_unlock(in);
1065 err1:
1066 	mutex_unlock(&ddata->lock);
1067 	return r;
1068 }
1069 
1070 static void dsicm_ulps_work(struct work_struct *work)
1071 {
1072 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
1073 			ulps_work.work);
1074 	struct omap_dss_device *dssdev = &ddata->dssdev;
1075 	struct omap_dss_device *in = ddata->in;
1076 
1077 	mutex_lock(&ddata->lock);
1078 
1079 	if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE || !ddata->enabled) {
1080 		mutex_unlock(&ddata->lock);
1081 		return;
1082 	}
1083 
1084 	in->ops.dsi->bus_lock(in);
1085 
1086 	dsicm_enter_ulps(ddata);
1087 
1088 	in->ops.dsi->bus_unlock(in);
1089 	mutex_unlock(&ddata->lock);
1090 }
1091 
1092 static struct omap_dss_driver dsicm_ops = {
1093 	.connect	= dsicm_connect,
1094 	.disconnect	= dsicm_disconnect,
1095 
1096 	.enable		= dsicm_enable,
1097 	.disable	= dsicm_disable,
1098 
1099 	.update		= dsicm_update,
1100 	.sync		= dsicm_sync,
1101 
1102 	.get_resolution	= dsicm_get_resolution,
1103 	.get_recommended_bpp = omapdss_default_get_recommended_bpp,
1104 
1105 	.enable_te	= dsicm_enable_te,
1106 	.get_te		= dsicm_get_te,
1107 
1108 	.memory_read	= dsicm_memory_read,
1109 };
1110 
1111 static int dsicm_probe(struct platform_device *pdev)
1112 {
1113 	struct backlight_properties props;
1114 	struct panel_drv_data *ddata;
1115 	struct backlight_device *bldev = NULL;
1116 	struct device *dev = &pdev->dev;
1117 	struct omap_dss_device *dssdev;
1118 	int r;
1119 
1120 	dev_dbg(dev, "probe\n");
1121 
1122 	if (!pdev->dev.of_node)
1123 		return -ENODEV;
1124 
1125 	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
1126 	if (!ddata)
1127 		return -ENOMEM;
1128 
1129 	platform_set_drvdata(pdev, ddata);
1130 	ddata->pdev = pdev;
1131 
1132 	ddata->in = omapdss_of_find_source_for_first_ep(pdev->dev.of_node);
1133 	r = PTR_ERR_OR_ZERO(ddata->in);
1134 	if (r) {
1135 		dev_err(&pdev->dev, "failed to find video source: %d\n", r);
1136 		return r;
1137 	}
1138 
1139 	ddata->timings.x_res = 864;
1140 	ddata->timings.y_res = 480;
1141 	ddata->timings.pixelclock = 864 * 480 * 60;
1142 
1143 	dssdev = &ddata->dssdev;
1144 	dssdev->dev = dev;
1145 	dssdev->driver = &dsicm_ops;
1146 	dssdev->panel.timings = ddata->timings;
1147 	dssdev->type = OMAP_DISPLAY_TYPE_DSI;
1148 	dssdev->owner = THIS_MODULE;
1149 
1150 	dssdev->panel.dsi_pix_fmt = OMAP_DSS_DSI_FMT_RGB888;
1151 	dssdev->caps = OMAP_DSS_DISPLAY_CAP_MANUAL_UPDATE |
1152 		OMAP_DSS_DISPLAY_CAP_TEAR_ELIM;
1153 
1154 	r = omapdss_register_display(dssdev);
1155 	if (r) {
1156 		dev_err(dev, "Failed to register panel\n");
1157 		goto err_reg;
1158 	}
1159 
1160 	mutex_init(&ddata->lock);
1161 
1162 	atomic_set(&ddata->do_update, 0);
1163 
1164 	ddata->reset_gpio = devm_gpiod_get(&pdev->dev, "reset", GPIOD_OUT_LOW);
1165 	r = PTR_ERR_OR_ZERO(ddata->reset_gpio);
1166 	if (r) {
1167 		dev_err(&pdev->dev, "Failed to request reset gpio: %d\n", r);
1168 		return r;
1169 	}
1170 
1171 	gpiod_set_consumer_name(ddata->reset_gpio, "taal rst");
1172 
1173 	ddata->ext_te_gpio = devm_gpiod_get_optional(&pdev->dev, "te",
1174 						     GPIOD_IN);
1175 	r = PTR_ERR_OR_ZERO(ddata->ext_te_gpio);
1176 	if (r) {
1177 		dev_err(&pdev->dev, "Failed to request TE gpio: %d\n", r);
1178 		return r;
1179 	}
1180 
1181 	if (ddata->ext_te_gpio) {
1182 		gpiod_set_consumer_name(ddata->ext_te_gpio, "taal irq");
1183 
1184 		r = devm_request_irq(dev, gpiod_to_irq(ddata->ext_te_gpio),
1185 				dsicm_te_isr,
1186 				IRQF_TRIGGER_RISING,
1187 				"taal vsync", ddata);
1188 
1189 		if (r) {
1190 			dev_err(dev, "IRQ request failed\n");
1191 			return r;
1192 		}
1193 
1194 		INIT_DEFERRABLE_WORK(&ddata->te_timeout_work,
1195 					dsicm_te_timeout_work_callback);
1196 
1197 		dev_dbg(dev, "Using GPIO TE\n");
1198 	}
1199 
1200 	INIT_DELAYED_WORK(&ddata->ulps_work, dsicm_ulps_work);
1201 
1202 	dsicm_hw_reset(ddata);
1203 
1204 	if (ddata->use_dsi_backlight) {
1205 		memset(&props, 0, sizeof(struct backlight_properties));
1206 		props.max_brightness = 255;
1207 
1208 		props.type = BACKLIGHT_RAW;
1209 		bldev = backlight_device_register(dev_name(dev),
1210 				dev, ddata, &dsicm_bl_ops, &props);
1211 		if (IS_ERR(bldev)) {
1212 			r = PTR_ERR(bldev);
1213 			goto err_reg;
1214 		}
1215 
1216 		ddata->bldev = bldev;
1217 
1218 		bldev->props.power = BACKLIGHT_POWER_ON;
1219 		bldev->props.brightness = 255;
1220 
1221 		dsicm_bl_update_status(bldev);
1222 	}
1223 
1224 	r = sysfs_create_group(&dev->kobj, &dsicm_attr_group);
1225 	if (r) {
1226 		dev_err(dev, "failed to create sysfs files\n");
1227 		goto err_sysfs_create;
1228 	}
1229 
1230 	return 0;
1231 
1232 err_sysfs_create:
1233 	if (bldev != NULL)
1234 		backlight_device_unregister(bldev);
1235 err_reg:
1236 	return r;
1237 }
1238 
1239 static void dsicm_remove(struct platform_device *pdev)
1240 {
1241 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
1242 	struct omap_dss_device *dssdev = &ddata->dssdev;
1243 	struct backlight_device *bldev;
1244 
1245 	dev_dbg(&pdev->dev, "remove\n");
1246 
1247 	omapdss_unregister_display(dssdev);
1248 
1249 	dsicm_disable(dssdev);
1250 	dsicm_disconnect(dssdev);
1251 
1252 	sysfs_remove_group(&pdev->dev.kobj, &dsicm_attr_group);
1253 
1254 	bldev = ddata->bldev;
1255 	if (bldev != NULL) {
1256 		bldev->props.power = BACKLIGHT_POWER_OFF;
1257 		dsicm_bl_update_status(bldev);
1258 		backlight_device_unregister(bldev);
1259 	}
1260 
1261 	omap_dss_put_device(ddata->in);
1262 
1263 	dsicm_cancel_ulps_work(ddata);
1264 
1265 	/* reset, to be sure that the panel is in a valid state */
1266 	dsicm_hw_reset(ddata);
1267 }
1268 
1269 static const struct of_device_id dsicm_of_match[] = {
1270 	{ .compatible = "omapdss,panel-dsi-cm", },
1271 	{},
1272 };
1273 
1274 MODULE_DEVICE_TABLE(of, dsicm_of_match);
1275 
1276 static struct platform_driver dsicm_driver = {
1277 	.probe = dsicm_probe,
1278 	.remove = dsicm_remove,
1279 	.driver = {
1280 		.name = "panel-dsi-cm",
1281 		.of_match_table = dsicm_of_match,
1282 	},
1283 };
1284 
1285 module_platform_driver(dsicm_driver);
1286 
1287 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
1288 MODULE_DESCRIPTION("Generic DSI Command Mode Panel Driver");
1289 MODULE_LICENSE("GPL");
1290