xref: /linux/drivers/video/fbdev/omap2/omapfb/displays/panel-dsi-cm.c (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
1 /*
2  * Generic DSI Command Mode panel driver
3  *
4  * Copyright (C) 2013 Texas Instruments
5  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License version 2 as published by
9  * the Free Software Foundation.
10  */
11 
12 /* #define DEBUG */
13 
14 #include <linux/backlight.h>
15 #include <linux/delay.h>
16 #include <linux/fb.h>
17 #include <linux/gpio.h>
18 #include <linux/interrupt.h>
19 #include <linux/jiffies.h>
20 #include <linux/module.h>
21 #include <linux/platform_device.h>
22 #include <linux/sched.h>
23 #include <linux/slab.h>
24 #include <linux/workqueue.h>
25 #include <linux/of_device.h>
26 #include <linux/of_gpio.h>
27 
28 #include <video/omapfb_dss.h>
29 #include <video/mipi_display.h>
30 
31 /* DSI Virtual channel. Hardcoded for now. */
32 #define TCH 0
33 
34 #define DCS_READ_NUM_ERRORS	0x05
35 #define DCS_BRIGHTNESS		0x51
36 #define DCS_CTRL_DISPLAY	0x53
37 #define DCS_GET_ID1		0xda
38 #define DCS_GET_ID2		0xdb
39 #define DCS_GET_ID3		0xdc
40 
41 struct panel_drv_data {
42 	struct omap_dss_device dssdev;
43 	struct omap_dss_device *in;
44 
45 	struct omap_video_timings timings;
46 
47 	struct platform_device *pdev;
48 
49 	struct mutex lock;
50 
51 	struct backlight_device *bldev;
52 
53 	unsigned long	hw_guard_end;	/* next value of jiffies when we can
54 					 * issue the next sleep in/out command
55 					 */
56 	unsigned long	hw_guard_wait;	/* max guard time in jiffies */
57 
58 	/* panel HW configuration from DT or platform data */
59 	int reset_gpio;
60 	int ext_te_gpio;
61 
62 	bool use_dsi_backlight;
63 
64 	struct omap_dsi_pin_config pin_config;
65 
66 	/* runtime variables */
67 	bool enabled;
68 
69 	bool te_enabled;
70 
71 	atomic_t do_update;
72 	int channel;
73 
74 	struct delayed_work te_timeout_work;
75 
76 	bool intro_printed;
77 
78 	struct workqueue_struct *workqueue;
79 
80 	bool ulps_enabled;
81 	unsigned ulps_timeout;
82 	struct delayed_work ulps_work;
83 };
84 
85 #define to_panel_data(p) container_of(p, struct panel_drv_data, dssdev)
86 
87 static irqreturn_t dsicm_te_isr(int irq, void *data);
88 static void dsicm_te_timeout_work_callback(struct work_struct *work);
89 static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable);
90 
91 static int dsicm_panel_reset(struct panel_drv_data *ddata);
92 
93 static void dsicm_ulps_work(struct work_struct *work);
94 
95 static void hw_guard_start(struct panel_drv_data *ddata, int guard_msec)
96 {
97 	ddata->hw_guard_wait = msecs_to_jiffies(guard_msec);
98 	ddata->hw_guard_end = jiffies + ddata->hw_guard_wait;
99 }
100 
101 static void hw_guard_wait(struct panel_drv_data *ddata)
102 {
103 	unsigned long wait = ddata->hw_guard_end - jiffies;
104 
105 	if ((long)wait > 0 && wait <= ddata->hw_guard_wait) {
106 		set_current_state(TASK_UNINTERRUPTIBLE);
107 		schedule_timeout(wait);
108 	}
109 }
110 
111 static int dsicm_dcs_read_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 *data)
112 {
113 	struct omap_dss_device *in = ddata->in;
114 	int r;
115 	u8 buf[1];
116 
117 	r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd, buf, 1);
118 
119 	if (r < 0)
120 		return r;
121 
122 	*data = buf[0];
123 
124 	return 0;
125 }
126 
127 static int dsicm_dcs_write_0(struct panel_drv_data *ddata, u8 dcs_cmd)
128 {
129 	struct omap_dss_device *in = ddata->in;
130 	return in->ops.dsi->dcs_write(in, ddata->channel, &dcs_cmd, 1);
131 }
132 
133 static int dsicm_dcs_write_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 param)
134 {
135 	struct omap_dss_device *in = ddata->in;
136 	u8 buf[2] = { dcs_cmd, param };
137 
138 	return in->ops.dsi->dcs_write(in, ddata->channel, buf, 2);
139 }
140 
141 static int dsicm_sleep_in(struct panel_drv_data *ddata)
142 
143 {
144 	struct omap_dss_device *in = ddata->in;
145 	u8 cmd;
146 	int r;
147 
148 	hw_guard_wait(ddata);
149 
150 	cmd = MIPI_DCS_ENTER_SLEEP_MODE;
151 	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, &cmd, 1);
152 	if (r)
153 		return r;
154 
155 	hw_guard_start(ddata, 120);
156 
157 	usleep_range(5000, 10000);
158 
159 	return 0;
160 }
161 
162 static int dsicm_sleep_out(struct panel_drv_data *ddata)
163 {
164 	int r;
165 
166 	hw_guard_wait(ddata);
167 
168 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_EXIT_SLEEP_MODE);
169 	if (r)
170 		return r;
171 
172 	hw_guard_start(ddata, 120);
173 
174 	usleep_range(5000, 10000);
175 
176 	return 0;
177 }
178 
179 static int dsicm_get_id(struct panel_drv_data *ddata, u8 *id1, u8 *id2, u8 *id3)
180 {
181 	int r;
182 
183 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID1, id1);
184 	if (r)
185 		return r;
186 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID2, id2);
187 	if (r)
188 		return r;
189 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID3, id3);
190 	if (r)
191 		return r;
192 
193 	return 0;
194 }
195 
196 static int dsicm_set_update_window(struct panel_drv_data *ddata,
197 		u16 x, u16 y, u16 w, u16 h)
198 {
199 	struct omap_dss_device *in = ddata->in;
200 	int r;
201 	u16 x1 = x;
202 	u16 x2 = x + w - 1;
203 	u16 y1 = y;
204 	u16 y2 = y + h - 1;
205 
206 	u8 buf[5];
207 	buf[0] = MIPI_DCS_SET_COLUMN_ADDRESS;
208 	buf[1] = (x1 >> 8) & 0xff;
209 	buf[2] = (x1 >> 0) & 0xff;
210 	buf[3] = (x2 >> 8) & 0xff;
211 	buf[4] = (x2 >> 0) & 0xff;
212 
213 	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, buf, sizeof(buf));
214 	if (r)
215 		return r;
216 
217 	buf[0] = MIPI_DCS_SET_PAGE_ADDRESS;
218 	buf[1] = (y1 >> 8) & 0xff;
219 	buf[2] = (y1 >> 0) & 0xff;
220 	buf[3] = (y2 >> 8) & 0xff;
221 	buf[4] = (y2 >> 0) & 0xff;
222 
223 	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, buf, sizeof(buf));
224 	if (r)
225 		return r;
226 
227 	in->ops.dsi->bta_sync(in, ddata->channel);
228 
229 	return r;
230 }
231 
232 static void dsicm_queue_ulps_work(struct panel_drv_data *ddata)
233 {
234 	if (ddata->ulps_timeout > 0)
235 		queue_delayed_work(ddata->workqueue, &ddata->ulps_work,
236 				msecs_to_jiffies(ddata->ulps_timeout));
237 }
238 
239 static void dsicm_cancel_ulps_work(struct panel_drv_data *ddata)
240 {
241 	cancel_delayed_work(&ddata->ulps_work);
242 }
243 
244 static int dsicm_enter_ulps(struct panel_drv_data *ddata)
245 {
246 	struct omap_dss_device *in = ddata->in;
247 	int r;
248 
249 	if (ddata->ulps_enabled)
250 		return 0;
251 
252 	dsicm_cancel_ulps_work(ddata);
253 
254 	r = _dsicm_enable_te(ddata, false);
255 	if (r)
256 		goto err;
257 
258 	if (gpio_is_valid(ddata->ext_te_gpio))
259 		disable_irq(gpio_to_irq(ddata->ext_te_gpio));
260 
261 	in->ops.dsi->disable(in, false, true);
262 
263 	ddata->ulps_enabled = true;
264 
265 	return 0;
266 
267 err:
268 	dev_err(&ddata->pdev->dev, "enter ULPS failed");
269 	dsicm_panel_reset(ddata);
270 
271 	ddata->ulps_enabled = false;
272 
273 	dsicm_queue_ulps_work(ddata);
274 
275 	return r;
276 }
277 
278 static int dsicm_exit_ulps(struct panel_drv_data *ddata)
279 {
280 	struct omap_dss_device *in = ddata->in;
281 	int r;
282 
283 	if (!ddata->ulps_enabled)
284 		return 0;
285 
286 	r = in->ops.dsi->enable(in);
287 	if (r) {
288 		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
289 		goto err1;
290 	}
291 
292 	in->ops.dsi->enable_hs(in, ddata->channel, true);
293 
294 	r = _dsicm_enable_te(ddata, true);
295 	if (r) {
296 		dev_err(&ddata->pdev->dev, "failed to re-enable TE");
297 		goto err2;
298 	}
299 
300 	if (gpio_is_valid(ddata->ext_te_gpio))
301 		enable_irq(gpio_to_irq(ddata->ext_te_gpio));
302 
303 	dsicm_queue_ulps_work(ddata);
304 
305 	ddata->ulps_enabled = false;
306 
307 	return 0;
308 
309 err2:
310 	dev_err(&ddata->pdev->dev, "failed to exit ULPS");
311 
312 	r = dsicm_panel_reset(ddata);
313 	if (!r) {
314 		if (gpio_is_valid(ddata->ext_te_gpio))
315 			enable_irq(gpio_to_irq(ddata->ext_te_gpio));
316 		ddata->ulps_enabled = false;
317 	}
318 err1:
319 	dsicm_queue_ulps_work(ddata);
320 
321 	return r;
322 }
323 
324 static int dsicm_wake_up(struct panel_drv_data *ddata)
325 {
326 	if (ddata->ulps_enabled)
327 		return dsicm_exit_ulps(ddata);
328 
329 	dsicm_cancel_ulps_work(ddata);
330 	dsicm_queue_ulps_work(ddata);
331 	return 0;
332 }
333 
334 static int dsicm_bl_update_status(struct backlight_device *dev)
335 {
336 	struct panel_drv_data *ddata = dev_get_drvdata(&dev->dev);
337 	struct omap_dss_device *in = ddata->in;
338 	int r;
339 	int level;
340 
341 	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
342 			dev->props.power == FB_BLANK_UNBLANK)
343 		level = dev->props.brightness;
344 	else
345 		level = 0;
346 
347 	dev_dbg(&ddata->pdev->dev, "update brightness to %d\n", level);
348 
349 	mutex_lock(&ddata->lock);
350 
351 	if (ddata->enabled) {
352 		in->ops.dsi->bus_lock(in);
353 
354 		r = dsicm_wake_up(ddata);
355 		if (!r)
356 			r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, level);
357 
358 		in->ops.dsi->bus_unlock(in);
359 	} else {
360 		r = 0;
361 	}
362 
363 	mutex_unlock(&ddata->lock);
364 
365 	return r;
366 }
367 
368 static int dsicm_bl_get_intensity(struct backlight_device *dev)
369 {
370 	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
371 			dev->props.power == FB_BLANK_UNBLANK)
372 		return dev->props.brightness;
373 
374 	return 0;
375 }
376 
377 static const struct backlight_ops dsicm_bl_ops = {
378 	.get_brightness = dsicm_bl_get_intensity,
379 	.update_status  = dsicm_bl_update_status,
380 };
381 
382 static void dsicm_get_resolution(struct omap_dss_device *dssdev,
383 		u16 *xres, u16 *yres)
384 {
385 	*xres = dssdev->panel.timings.x_res;
386 	*yres = dssdev->panel.timings.y_res;
387 }
388 
389 static ssize_t dsicm_num_errors_show(struct device *dev,
390 		struct device_attribute *attr, char *buf)
391 {
392 	struct platform_device *pdev = to_platform_device(dev);
393 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
394 	struct omap_dss_device *in = ddata->in;
395 	u8 errors = 0;
396 	int r;
397 
398 	mutex_lock(&ddata->lock);
399 
400 	if (ddata->enabled) {
401 		in->ops.dsi->bus_lock(in);
402 
403 		r = dsicm_wake_up(ddata);
404 		if (!r)
405 			r = dsicm_dcs_read_1(ddata, DCS_READ_NUM_ERRORS,
406 					&errors);
407 
408 		in->ops.dsi->bus_unlock(in);
409 	} else {
410 		r = -ENODEV;
411 	}
412 
413 	mutex_unlock(&ddata->lock);
414 
415 	if (r)
416 		return r;
417 
418 	return snprintf(buf, PAGE_SIZE, "%d\n", errors);
419 }
420 
421 static ssize_t dsicm_hw_revision_show(struct device *dev,
422 		struct device_attribute *attr, char *buf)
423 {
424 	struct platform_device *pdev = to_platform_device(dev);
425 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
426 	struct omap_dss_device *in = ddata->in;
427 	u8 id1, id2, id3;
428 	int r;
429 
430 	mutex_lock(&ddata->lock);
431 
432 	if (ddata->enabled) {
433 		in->ops.dsi->bus_lock(in);
434 
435 		r = dsicm_wake_up(ddata);
436 		if (!r)
437 			r = dsicm_get_id(ddata, &id1, &id2, &id3);
438 
439 		in->ops.dsi->bus_unlock(in);
440 	} else {
441 		r = -ENODEV;
442 	}
443 
444 	mutex_unlock(&ddata->lock);
445 
446 	if (r)
447 		return r;
448 
449 	return snprintf(buf, PAGE_SIZE, "%02x.%02x.%02x\n", id1, id2, id3);
450 }
451 
452 static ssize_t dsicm_store_ulps(struct device *dev,
453 		struct device_attribute *attr,
454 		const char *buf, size_t count)
455 {
456 	struct platform_device *pdev = to_platform_device(dev);
457 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
458 	struct omap_dss_device *in = ddata->in;
459 	unsigned long t;
460 	int r;
461 
462 	r = kstrtoul(buf, 0, &t);
463 	if (r)
464 		return r;
465 
466 	mutex_lock(&ddata->lock);
467 
468 	if (ddata->enabled) {
469 		in->ops.dsi->bus_lock(in);
470 
471 		if (t)
472 			r = dsicm_enter_ulps(ddata);
473 		else
474 			r = dsicm_wake_up(ddata);
475 
476 		in->ops.dsi->bus_unlock(in);
477 	}
478 
479 	mutex_unlock(&ddata->lock);
480 
481 	if (r)
482 		return r;
483 
484 	return count;
485 }
486 
487 static ssize_t dsicm_show_ulps(struct device *dev,
488 		struct device_attribute *attr,
489 		char *buf)
490 {
491 	struct platform_device *pdev = to_platform_device(dev);
492 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
493 	unsigned t;
494 
495 	mutex_lock(&ddata->lock);
496 	t = ddata->ulps_enabled;
497 	mutex_unlock(&ddata->lock);
498 
499 	return snprintf(buf, PAGE_SIZE, "%u\n", t);
500 }
501 
502 static ssize_t dsicm_store_ulps_timeout(struct device *dev,
503 		struct device_attribute *attr,
504 		const char *buf, size_t count)
505 {
506 	struct platform_device *pdev = to_platform_device(dev);
507 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
508 	struct omap_dss_device *in = ddata->in;
509 	unsigned long t;
510 	int r;
511 
512 	r = kstrtoul(buf, 0, &t);
513 	if (r)
514 		return r;
515 
516 	mutex_lock(&ddata->lock);
517 	ddata->ulps_timeout = t;
518 
519 	if (ddata->enabled) {
520 		/* dsicm_wake_up will restart the timer */
521 		in->ops.dsi->bus_lock(in);
522 		r = dsicm_wake_up(ddata);
523 		in->ops.dsi->bus_unlock(in);
524 	}
525 
526 	mutex_unlock(&ddata->lock);
527 
528 	if (r)
529 		return r;
530 
531 	return count;
532 }
533 
534 static ssize_t dsicm_show_ulps_timeout(struct device *dev,
535 		struct device_attribute *attr,
536 		char *buf)
537 {
538 	struct platform_device *pdev = to_platform_device(dev);
539 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
540 	unsigned t;
541 
542 	mutex_lock(&ddata->lock);
543 	t = ddata->ulps_timeout;
544 	mutex_unlock(&ddata->lock);
545 
546 	return snprintf(buf, PAGE_SIZE, "%u\n", t);
547 }
548 
549 static DEVICE_ATTR(num_dsi_errors, S_IRUGO, dsicm_num_errors_show, NULL);
550 static DEVICE_ATTR(hw_revision, S_IRUGO, dsicm_hw_revision_show, NULL);
551 static DEVICE_ATTR(ulps, S_IRUGO | S_IWUSR,
552 		dsicm_show_ulps, dsicm_store_ulps);
553 static DEVICE_ATTR(ulps_timeout, S_IRUGO | S_IWUSR,
554 		dsicm_show_ulps_timeout, dsicm_store_ulps_timeout);
555 
556 static struct attribute *dsicm_attrs[] = {
557 	&dev_attr_num_dsi_errors.attr,
558 	&dev_attr_hw_revision.attr,
559 	&dev_attr_ulps.attr,
560 	&dev_attr_ulps_timeout.attr,
561 	NULL,
562 };
563 
564 static struct attribute_group dsicm_attr_group = {
565 	.attrs = dsicm_attrs,
566 };
567 
568 static void dsicm_hw_reset(struct panel_drv_data *ddata)
569 {
570 	if (!gpio_is_valid(ddata->reset_gpio))
571 		return;
572 
573 	gpio_set_value(ddata->reset_gpio, 1);
574 	udelay(10);
575 	/* reset the panel */
576 	gpio_set_value(ddata->reset_gpio, 0);
577 	/* assert reset */
578 	udelay(10);
579 	gpio_set_value(ddata->reset_gpio, 1);
580 	/* wait after releasing reset */
581 	usleep_range(5000, 10000);
582 }
583 
584 static int dsicm_power_on(struct panel_drv_data *ddata)
585 {
586 	struct omap_dss_device *in = ddata->in;
587 	u8 id1, id2, id3;
588 	int r;
589 	struct omap_dss_dsi_config dsi_config = {
590 		.mode = OMAP_DSS_DSI_CMD_MODE,
591 		.pixel_format = OMAP_DSS_DSI_FMT_RGB888,
592 		.timings = &ddata->timings,
593 		.hs_clk_min = 150000000,
594 		.hs_clk_max = 300000000,
595 		.lp_clk_min = 7000000,
596 		.lp_clk_max = 10000000,
597 	};
598 
599 	if (ddata->pin_config.num_pins > 0) {
600 		r = in->ops.dsi->configure_pins(in, &ddata->pin_config);
601 		if (r) {
602 			dev_err(&ddata->pdev->dev,
603 				"failed to configure DSI pins\n");
604 			goto err0;
605 		}
606 	}
607 
608 	r = in->ops.dsi->set_config(in, &dsi_config);
609 	if (r) {
610 		dev_err(&ddata->pdev->dev, "failed to configure DSI\n");
611 		goto err0;
612 	}
613 
614 	r = in->ops.dsi->enable(in);
615 	if (r) {
616 		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
617 		goto err0;
618 	}
619 
620 	dsicm_hw_reset(ddata);
621 
622 	in->ops.dsi->enable_hs(in, ddata->channel, false);
623 
624 	r = dsicm_sleep_out(ddata);
625 	if (r)
626 		goto err;
627 
628 	r = dsicm_get_id(ddata, &id1, &id2, &id3);
629 	if (r)
630 		goto err;
631 
632 	r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, 0xff);
633 	if (r)
634 		goto err;
635 
636 	r = dsicm_dcs_write_1(ddata, DCS_CTRL_DISPLAY,
637 			(1<<2) | (1<<5));	/* BL | BCTRL */
638 	if (r)
639 		goto err;
640 
641 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_PIXEL_FORMAT,
642 		MIPI_DCS_PIXEL_FMT_24BIT);
643 	if (r)
644 		goto err;
645 
646 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_ON);
647 	if (r)
648 		goto err;
649 
650 	r = _dsicm_enable_te(ddata, ddata->te_enabled);
651 	if (r)
652 		goto err;
653 
654 	r = in->ops.dsi->enable_video_output(in, ddata->channel);
655 	if (r)
656 		goto err;
657 
658 	ddata->enabled = 1;
659 
660 	if (!ddata->intro_printed) {
661 		dev_info(&ddata->pdev->dev, "panel revision %02x.%02x.%02x\n",
662 			id1, id2, id3);
663 		ddata->intro_printed = true;
664 	}
665 
666 	in->ops.dsi->enable_hs(in, ddata->channel, true);
667 
668 	return 0;
669 err:
670 	dev_err(&ddata->pdev->dev, "error while enabling panel, issuing HW reset\n");
671 
672 	dsicm_hw_reset(ddata);
673 
674 	in->ops.dsi->disable(in, true, false);
675 err0:
676 	return r;
677 }
678 
679 static void dsicm_power_off(struct panel_drv_data *ddata)
680 {
681 	struct omap_dss_device *in = ddata->in;
682 	int r;
683 
684 	in->ops.dsi->disable_video_output(in, ddata->channel);
685 
686 	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_OFF);
687 	if (!r)
688 		r = dsicm_sleep_in(ddata);
689 
690 	if (r) {
691 		dev_err(&ddata->pdev->dev,
692 				"error disabling panel, issuing HW reset\n");
693 		dsicm_hw_reset(ddata);
694 	}
695 
696 	in->ops.dsi->disable(in, true, false);
697 
698 	ddata->enabled = 0;
699 }
700 
701 static int dsicm_panel_reset(struct panel_drv_data *ddata)
702 {
703 	dev_err(&ddata->pdev->dev, "performing LCD reset\n");
704 
705 	dsicm_power_off(ddata);
706 	dsicm_hw_reset(ddata);
707 	return dsicm_power_on(ddata);
708 }
709 
710 static int dsicm_connect(struct omap_dss_device *dssdev)
711 {
712 	struct panel_drv_data *ddata = to_panel_data(dssdev);
713 	struct omap_dss_device *in = ddata->in;
714 	struct device *dev = &ddata->pdev->dev;
715 	int r;
716 
717 	if (omapdss_device_is_connected(dssdev))
718 		return 0;
719 
720 	r = in->ops.dsi->connect(in, dssdev);
721 	if (r) {
722 		dev_err(dev, "Failed to connect to video source\n");
723 		return r;
724 	}
725 
726 	r = in->ops.dsi->request_vc(ddata->in, &ddata->channel);
727 	if (r) {
728 		dev_err(dev, "failed to get virtual channel\n");
729 		goto err_req_vc;
730 	}
731 
732 	r = in->ops.dsi->set_vc_id(ddata->in, ddata->channel, TCH);
733 	if (r) {
734 		dev_err(dev, "failed to set VC_ID\n");
735 		goto err_vc_id;
736 	}
737 
738 	return 0;
739 
740 err_vc_id:
741 	in->ops.dsi->release_vc(ddata->in, ddata->channel);
742 err_req_vc:
743 	in->ops.dsi->disconnect(in, dssdev);
744 	return r;
745 }
746 
747 static void dsicm_disconnect(struct omap_dss_device *dssdev)
748 {
749 	struct panel_drv_data *ddata = to_panel_data(dssdev);
750 	struct omap_dss_device *in = ddata->in;
751 
752 	if (!omapdss_device_is_connected(dssdev))
753 		return;
754 
755 	in->ops.dsi->release_vc(in, ddata->channel);
756 	in->ops.dsi->disconnect(in, dssdev);
757 }
758 
759 static int dsicm_enable(struct omap_dss_device *dssdev)
760 {
761 	struct panel_drv_data *ddata = to_panel_data(dssdev);
762 	struct omap_dss_device *in = ddata->in;
763 	int r;
764 
765 	dev_dbg(&ddata->pdev->dev, "enable\n");
766 
767 	mutex_lock(&ddata->lock);
768 
769 	if (!omapdss_device_is_connected(dssdev)) {
770 		r = -ENODEV;
771 		goto err;
772 	}
773 
774 	if (omapdss_device_is_enabled(dssdev)) {
775 		r = 0;
776 		goto err;
777 	}
778 
779 	in->ops.dsi->bus_lock(in);
780 
781 	r = dsicm_power_on(ddata);
782 
783 	in->ops.dsi->bus_unlock(in);
784 
785 	if (r)
786 		goto err;
787 
788 	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
789 
790 	mutex_unlock(&ddata->lock);
791 
792 	return 0;
793 err:
794 	dev_dbg(&ddata->pdev->dev, "enable failed\n");
795 	mutex_unlock(&ddata->lock);
796 	return r;
797 }
798 
799 static void dsicm_disable(struct omap_dss_device *dssdev)
800 {
801 	struct panel_drv_data *ddata = to_panel_data(dssdev);
802 	struct omap_dss_device *in = ddata->in;
803 	int r;
804 
805 	dev_dbg(&ddata->pdev->dev, "disable\n");
806 
807 	mutex_lock(&ddata->lock);
808 
809 	dsicm_cancel_ulps_work(ddata);
810 
811 	in->ops.dsi->bus_lock(in);
812 
813 	if (omapdss_device_is_enabled(dssdev)) {
814 		r = dsicm_wake_up(ddata);
815 		if (!r)
816 			dsicm_power_off(ddata);
817 	}
818 
819 	in->ops.dsi->bus_unlock(in);
820 
821 	dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
822 
823 	mutex_unlock(&ddata->lock);
824 }
825 
826 static void dsicm_framedone_cb(int err, void *data)
827 {
828 	struct panel_drv_data *ddata = data;
829 	struct omap_dss_device *in = ddata->in;
830 
831 	dev_dbg(&ddata->pdev->dev, "framedone, err %d\n", err);
832 	in->ops.dsi->bus_unlock(ddata->in);
833 }
834 
835 static irqreturn_t dsicm_te_isr(int irq, void *data)
836 {
837 	struct panel_drv_data *ddata = data;
838 	struct omap_dss_device *in = ddata->in;
839 	int old;
840 	int r;
841 
842 	old = atomic_cmpxchg(&ddata->do_update, 1, 0);
843 
844 	if (old) {
845 		cancel_delayed_work(&ddata->te_timeout_work);
846 
847 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
848 				ddata);
849 		if (r)
850 			goto err;
851 	}
852 
853 	return IRQ_HANDLED;
854 err:
855 	dev_err(&ddata->pdev->dev, "start update failed\n");
856 	in->ops.dsi->bus_unlock(in);
857 	return IRQ_HANDLED;
858 }
859 
860 static void dsicm_te_timeout_work_callback(struct work_struct *work)
861 {
862 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
863 					te_timeout_work.work);
864 	struct omap_dss_device *in = ddata->in;
865 
866 	dev_err(&ddata->pdev->dev, "TE not received for 250ms!\n");
867 
868 	atomic_set(&ddata->do_update, 0);
869 	in->ops.dsi->bus_unlock(in);
870 }
871 
872 static int dsicm_update(struct omap_dss_device *dssdev,
873 				    u16 x, u16 y, u16 w, u16 h)
874 {
875 	struct panel_drv_data *ddata = to_panel_data(dssdev);
876 	struct omap_dss_device *in = ddata->in;
877 	int r;
878 
879 	dev_dbg(&ddata->pdev->dev, "update %d, %d, %d x %d\n", x, y, w, h);
880 
881 	mutex_lock(&ddata->lock);
882 	in->ops.dsi->bus_lock(in);
883 
884 	r = dsicm_wake_up(ddata);
885 	if (r)
886 		goto err;
887 
888 	if (!ddata->enabled) {
889 		r = 0;
890 		goto err;
891 	}
892 
893 	/* XXX no need to send this every frame, but dsi break if not done */
894 	r = dsicm_set_update_window(ddata, 0, 0,
895 			dssdev->panel.timings.x_res,
896 			dssdev->panel.timings.y_res);
897 	if (r)
898 		goto err;
899 
900 	if (ddata->te_enabled && gpio_is_valid(ddata->ext_te_gpio)) {
901 		schedule_delayed_work(&ddata->te_timeout_work,
902 				msecs_to_jiffies(250));
903 		atomic_set(&ddata->do_update, 1);
904 	} else {
905 		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
906 				ddata);
907 		if (r)
908 			goto err;
909 	}
910 
911 	/* note: no bus_unlock here. unlock is in framedone_cb */
912 	mutex_unlock(&ddata->lock);
913 	return 0;
914 err:
915 	in->ops.dsi->bus_unlock(in);
916 	mutex_unlock(&ddata->lock);
917 	return r;
918 }
919 
920 static int dsicm_sync(struct omap_dss_device *dssdev)
921 {
922 	struct panel_drv_data *ddata = to_panel_data(dssdev);
923 	struct omap_dss_device *in = ddata->in;
924 
925 	dev_dbg(&ddata->pdev->dev, "sync\n");
926 
927 	mutex_lock(&ddata->lock);
928 	in->ops.dsi->bus_lock(in);
929 	in->ops.dsi->bus_unlock(in);
930 	mutex_unlock(&ddata->lock);
931 
932 	dev_dbg(&ddata->pdev->dev, "sync done\n");
933 
934 	return 0;
935 }
936 
937 static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable)
938 {
939 	struct omap_dss_device *in = ddata->in;
940 	int r;
941 
942 	if (enable)
943 		r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_TEAR_ON, 0);
944 	else
945 		r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_TEAR_OFF);
946 
947 	if (!gpio_is_valid(ddata->ext_te_gpio))
948 		in->ops.dsi->enable_te(in, enable);
949 
950 	/* possible panel bug */
951 	msleep(100);
952 
953 	return r;
954 }
955 
956 static int dsicm_enable_te(struct omap_dss_device *dssdev, bool enable)
957 {
958 	struct panel_drv_data *ddata = to_panel_data(dssdev);
959 	struct omap_dss_device *in = ddata->in;
960 	int r;
961 
962 	mutex_lock(&ddata->lock);
963 
964 	if (ddata->te_enabled == enable)
965 		goto end;
966 
967 	in->ops.dsi->bus_lock(in);
968 
969 	if (ddata->enabled) {
970 		r = dsicm_wake_up(ddata);
971 		if (r)
972 			goto err;
973 
974 		r = _dsicm_enable_te(ddata, enable);
975 		if (r)
976 			goto err;
977 	}
978 
979 	ddata->te_enabled = enable;
980 
981 	in->ops.dsi->bus_unlock(in);
982 end:
983 	mutex_unlock(&ddata->lock);
984 
985 	return 0;
986 err:
987 	in->ops.dsi->bus_unlock(in);
988 	mutex_unlock(&ddata->lock);
989 
990 	return r;
991 }
992 
993 static int dsicm_get_te(struct omap_dss_device *dssdev)
994 {
995 	struct panel_drv_data *ddata = to_panel_data(dssdev);
996 	int r;
997 
998 	mutex_lock(&ddata->lock);
999 	r = ddata->te_enabled;
1000 	mutex_unlock(&ddata->lock);
1001 
1002 	return r;
1003 }
1004 
1005 static int dsicm_memory_read(struct omap_dss_device *dssdev,
1006 		void *buf, size_t size,
1007 		u16 x, u16 y, u16 w, u16 h)
1008 {
1009 	struct panel_drv_data *ddata = to_panel_data(dssdev);
1010 	struct omap_dss_device *in = ddata->in;
1011 	int r;
1012 	int first = 1;
1013 	int plen;
1014 	unsigned buf_used = 0;
1015 
1016 	if (size < w * h * 3)
1017 		return -ENOMEM;
1018 
1019 	mutex_lock(&ddata->lock);
1020 
1021 	if (!ddata->enabled) {
1022 		r = -ENODEV;
1023 		goto err1;
1024 	}
1025 
1026 	size = min(w * h * 3,
1027 			dssdev->panel.timings.x_res *
1028 			dssdev->panel.timings.y_res * 3);
1029 
1030 	in->ops.dsi->bus_lock(in);
1031 
1032 	r = dsicm_wake_up(ddata);
1033 	if (r)
1034 		goto err2;
1035 
1036 	/* plen 1 or 2 goes into short packet. until checksum error is fixed,
1037 	 * use short packets. plen 32 works, but bigger packets seem to cause
1038 	 * an error. */
1039 	if (size % 2)
1040 		plen = 1;
1041 	else
1042 		plen = 2;
1043 
1044 	dsicm_set_update_window(ddata, x, y, w, h);
1045 
1046 	r = in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, plen);
1047 	if (r)
1048 		goto err2;
1049 
1050 	while (buf_used < size) {
1051 		u8 dcs_cmd = first ? 0x2e : 0x3e;
1052 		first = 0;
1053 
1054 		r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd,
1055 				buf + buf_used, size - buf_used);
1056 
1057 		if (r < 0) {
1058 			dev_err(dssdev->dev, "read error\n");
1059 			goto err3;
1060 		}
1061 
1062 		buf_used += r;
1063 
1064 		if (r < plen) {
1065 			dev_err(&ddata->pdev->dev, "short read\n");
1066 			break;
1067 		}
1068 
1069 		if (signal_pending(current)) {
1070 			dev_err(&ddata->pdev->dev, "signal pending, "
1071 					"aborting memory read\n");
1072 			r = -ERESTARTSYS;
1073 			goto err3;
1074 		}
1075 	}
1076 
1077 	r = buf_used;
1078 
1079 err3:
1080 	in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, 1);
1081 err2:
1082 	in->ops.dsi->bus_unlock(in);
1083 err1:
1084 	mutex_unlock(&ddata->lock);
1085 	return r;
1086 }
1087 
1088 static void dsicm_ulps_work(struct work_struct *work)
1089 {
1090 	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
1091 			ulps_work.work);
1092 	struct omap_dss_device *dssdev = &ddata->dssdev;
1093 	struct omap_dss_device *in = ddata->in;
1094 
1095 	mutex_lock(&ddata->lock);
1096 
1097 	if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE || !ddata->enabled) {
1098 		mutex_unlock(&ddata->lock);
1099 		return;
1100 	}
1101 
1102 	in->ops.dsi->bus_lock(in);
1103 
1104 	dsicm_enter_ulps(ddata);
1105 
1106 	in->ops.dsi->bus_unlock(in);
1107 	mutex_unlock(&ddata->lock);
1108 }
1109 
1110 static struct omap_dss_driver dsicm_ops = {
1111 	.connect	= dsicm_connect,
1112 	.disconnect	= dsicm_disconnect,
1113 
1114 	.enable		= dsicm_enable,
1115 	.disable	= dsicm_disable,
1116 
1117 	.update		= dsicm_update,
1118 	.sync		= dsicm_sync,
1119 
1120 	.get_resolution	= dsicm_get_resolution,
1121 	.get_recommended_bpp = omapdss_default_get_recommended_bpp,
1122 
1123 	.enable_te	= dsicm_enable_te,
1124 	.get_te		= dsicm_get_te,
1125 
1126 	.memory_read	= dsicm_memory_read,
1127 };
1128 
1129 static int dsicm_probe_of(struct platform_device *pdev)
1130 {
1131 	struct device_node *node = pdev->dev.of_node;
1132 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
1133 	struct omap_dss_device *in;
1134 	int gpio;
1135 
1136 	gpio = of_get_named_gpio(node, "reset-gpios", 0);
1137 	if (!gpio_is_valid(gpio)) {
1138 		dev_err(&pdev->dev, "failed to parse reset gpio\n");
1139 		return gpio;
1140 	}
1141 	ddata->reset_gpio = gpio;
1142 
1143 	gpio = of_get_named_gpio(node, "te-gpios", 0);
1144 	if (gpio_is_valid(gpio) || gpio == -ENOENT) {
1145 		ddata->ext_te_gpio = gpio;
1146 	} else {
1147 		dev_err(&pdev->dev, "failed to parse TE gpio\n");
1148 		return gpio;
1149 	}
1150 
1151 	in = omapdss_of_find_source_for_first_ep(node);
1152 	if (IS_ERR(in)) {
1153 		dev_err(&pdev->dev, "failed to find video source\n");
1154 		return PTR_ERR(in);
1155 	}
1156 
1157 	ddata->in = in;
1158 
1159 	/* TODO: ulps, backlight */
1160 
1161 	return 0;
1162 }
1163 
1164 static int dsicm_probe(struct platform_device *pdev)
1165 {
1166 	struct backlight_properties props;
1167 	struct panel_drv_data *ddata;
1168 	struct backlight_device *bldev = NULL;
1169 	struct device *dev = &pdev->dev;
1170 	struct omap_dss_device *dssdev;
1171 	int r;
1172 
1173 	dev_dbg(dev, "probe\n");
1174 
1175 	if (!pdev->dev.of_node)
1176 		return -ENODEV;
1177 
1178 	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
1179 	if (!ddata)
1180 		return -ENOMEM;
1181 
1182 	platform_set_drvdata(pdev, ddata);
1183 	ddata->pdev = pdev;
1184 
1185 	r = dsicm_probe_of(pdev);
1186 	if (r)
1187 		return r;
1188 
1189 	ddata->timings.x_res = 864;
1190 	ddata->timings.y_res = 480;
1191 	ddata->timings.pixelclock = 864 * 480 * 60;
1192 
1193 	dssdev = &ddata->dssdev;
1194 	dssdev->dev = dev;
1195 	dssdev->driver = &dsicm_ops;
1196 	dssdev->panel.timings = ddata->timings;
1197 	dssdev->type = OMAP_DISPLAY_TYPE_DSI;
1198 	dssdev->owner = THIS_MODULE;
1199 
1200 	dssdev->panel.dsi_pix_fmt = OMAP_DSS_DSI_FMT_RGB888;
1201 	dssdev->caps = OMAP_DSS_DISPLAY_CAP_MANUAL_UPDATE |
1202 		OMAP_DSS_DISPLAY_CAP_TEAR_ELIM;
1203 
1204 	r = omapdss_register_display(dssdev);
1205 	if (r) {
1206 		dev_err(dev, "Failed to register panel\n");
1207 		goto err_reg;
1208 	}
1209 
1210 	mutex_init(&ddata->lock);
1211 
1212 	atomic_set(&ddata->do_update, 0);
1213 
1214 	if (gpio_is_valid(ddata->reset_gpio)) {
1215 		r = devm_gpio_request_one(dev, ddata->reset_gpio,
1216 				GPIOF_OUT_INIT_LOW, "taal rst");
1217 		if (r) {
1218 			dev_err(dev, "failed to request reset gpio\n");
1219 			return r;
1220 		}
1221 	}
1222 
1223 	if (gpio_is_valid(ddata->ext_te_gpio)) {
1224 		r = devm_gpio_request_one(dev, ddata->ext_te_gpio,
1225 				GPIOF_IN, "taal irq");
1226 		if (r) {
1227 			dev_err(dev, "GPIO request failed\n");
1228 			return r;
1229 		}
1230 
1231 		r = devm_request_irq(dev, gpio_to_irq(ddata->ext_te_gpio),
1232 				dsicm_te_isr,
1233 				IRQF_TRIGGER_RISING,
1234 				"taal vsync", ddata);
1235 
1236 		if (r) {
1237 			dev_err(dev, "IRQ request failed\n");
1238 			return r;
1239 		}
1240 
1241 		INIT_DEFERRABLE_WORK(&ddata->te_timeout_work,
1242 					dsicm_te_timeout_work_callback);
1243 
1244 		dev_dbg(dev, "Using GPIO TE\n");
1245 	}
1246 
1247 	ddata->workqueue = create_singlethread_workqueue("dsicm_wq");
1248 	if (ddata->workqueue == NULL) {
1249 		dev_err(dev, "can't create workqueue\n");
1250 		return -ENOMEM;
1251 	}
1252 	INIT_DELAYED_WORK(&ddata->ulps_work, dsicm_ulps_work);
1253 
1254 	dsicm_hw_reset(ddata);
1255 
1256 	if (ddata->use_dsi_backlight) {
1257 		memset(&props, 0, sizeof(struct backlight_properties));
1258 		props.max_brightness = 255;
1259 
1260 		props.type = BACKLIGHT_RAW;
1261 		bldev = backlight_device_register(dev_name(dev),
1262 				dev, ddata, &dsicm_bl_ops, &props);
1263 		if (IS_ERR(bldev)) {
1264 			r = PTR_ERR(bldev);
1265 			goto err_bl;
1266 		}
1267 
1268 		ddata->bldev = bldev;
1269 
1270 		bldev->props.fb_blank = FB_BLANK_UNBLANK;
1271 		bldev->props.power = FB_BLANK_UNBLANK;
1272 		bldev->props.brightness = 255;
1273 
1274 		dsicm_bl_update_status(bldev);
1275 	}
1276 
1277 	r = sysfs_create_group(&dev->kobj, &dsicm_attr_group);
1278 	if (r) {
1279 		dev_err(dev, "failed to create sysfs files\n");
1280 		goto err_sysfs_create;
1281 	}
1282 
1283 	return 0;
1284 
1285 err_sysfs_create:
1286 	if (bldev != NULL)
1287 		backlight_device_unregister(bldev);
1288 err_bl:
1289 	destroy_workqueue(ddata->workqueue);
1290 err_reg:
1291 	return r;
1292 }
1293 
1294 static int __exit dsicm_remove(struct platform_device *pdev)
1295 {
1296 	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
1297 	struct omap_dss_device *dssdev = &ddata->dssdev;
1298 	struct backlight_device *bldev;
1299 
1300 	dev_dbg(&pdev->dev, "remove\n");
1301 
1302 	omapdss_unregister_display(dssdev);
1303 
1304 	dsicm_disable(dssdev);
1305 	dsicm_disconnect(dssdev);
1306 
1307 	sysfs_remove_group(&pdev->dev.kobj, &dsicm_attr_group);
1308 
1309 	bldev = ddata->bldev;
1310 	if (bldev != NULL) {
1311 		bldev->props.power = FB_BLANK_POWERDOWN;
1312 		dsicm_bl_update_status(bldev);
1313 		backlight_device_unregister(bldev);
1314 	}
1315 
1316 	omap_dss_put_device(ddata->in);
1317 
1318 	dsicm_cancel_ulps_work(ddata);
1319 	destroy_workqueue(ddata->workqueue);
1320 
1321 	/* reset, to be sure that the panel is in a valid state */
1322 	dsicm_hw_reset(ddata);
1323 
1324 	return 0;
1325 }
1326 
1327 static const struct of_device_id dsicm_of_match[] = {
1328 	{ .compatible = "omapdss,panel-dsi-cm", },
1329 	{},
1330 };
1331 
1332 MODULE_DEVICE_TABLE(of, dsicm_of_match);
1333 
1334 static struct platform_driver dsicm_driver = {
1335 	.probe = dsicm_probe,
1336 	.remove = __exit_p(dsicm_remove),
1337 	.driver = {
1338 		.name = "panel-dsi-cm",
1339 		.of_match_table = dsicm_of_match,
1340 		.suppress_bind_attrs = true,
1341 	},
1342 };
1343 
1344 module_platform_driver(dsicm_driver);
1345 
1346 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
1347 MODULE_DESCRIPTION("Generic DSI Command Mode Panel Driver");
1348 MODULE_LICENSE("GPL");
1349