xref: /linux/drivers/gpu/drm/tilcdc/tilcdc_drv.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2  * Copyright (C) 2012 Texas Instruments
3  * Author: Rob Clark <robdclark@gmail.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 as published by
7  * the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 /* LCDC DRM driver, based on da8xx-fb */
19 
20 #include "tilcdc_drv.h"
21 #include "tilcdc_regs.h"
22 #include "tilcdc_tfp410.h"
23 #include "tilcdc_slave.h"
24 #include "tilcdc_panel.h"
25 
26 #include "drm_fb_helper.h"
27 
28 static LIST_HEAD(module_list);
29 static bool slave_probing;
30 
31 void tilcdc_module_init(struct tilcdc_module *mod, const char *name,
32 		const struct tilcdc_module_ops *funcs)
33 {
34 	mod->name = name;
35 	mod->funcs = funcs;
36 	INIT_LIST_HEAD(&mod->list);
37 	list_add(&mod->list, &module_list);
38 }
39 
40 void tilcdc_module_cleanup(struct tilcdc_module *mod)
41 {
42 	list_del(&mod->list);
43 }
44 
45 void tilcdc_slave_probedefer(bool defered)
46 {
47 	slave_probing = defered;
48 }
49 
50 static struct of_device_id tilcdc_of_match[];
51 
52 static struct drm_framebuffer *tilcdc_fb_create(struct drm_device *dev,
53 		struct drm_file *file_priv, struct drm_mode_fb_cmd2 *mode_cmd)
54 {
55 	return drm_fb_cma_create(dev, file_priv, mode_cmd);
56 }
57 
58 static void tilcdc_fb_output_poll_changed(struct drm_device *dev)
59 {
60 	struct tilcdc_drm_private *priv = dev->dev_private;
61 	if (priv->fbdev)
62 		drm_fbdev_cma_hotplug_event(priv->fbdev);
63 }
64 
65 static const struct drm_mode_config_funcs mode_config_funcs = {
66 	.fb_create = tilcdc_fb_create,
67 	.output_poll_changed = tilcdc_fb_output_poll_changed,
68 };
69 
70 static int modeset_init(struct drm_device *dev)
71 {
72 	struct tilcdc_drm_private *priv = dev->dev_private;
73 	struct tilcdc_module *mod;
74 
75 	drm_mode_config_init(dev);
76 
77 	priv->crtc = tilcdc_crtc_create(dev);
78 
79 	list_for_each_entry(mod, &module_list, list) {
80 		DBG("loading module: %s", mod->name);
81 		mod->funcs->modeset_init(mod, dev);
82 	}
83 
84 	if ((priv->num_encoders == 0) || (priv->num_connectors == 0)) {
85 		/* oh nos! */
86 		dev_err(dev->dev, "no encoders/connectors found\n");
87 		return -ENXIO;
88 	}
89 
90 	dev->mode_config.min_width = 0;
91 	dev->mode_config.min_height = 0;
92 	dev->mode_config.max_width = tilcdc_crtc_max_width(priv->crtc);
93 	dev->mode_config.max_height = 2048;
94 	dev->mode_config.funcs = &mode_config_funcs;
95 
96 	return 0;
97 }
98 
99 #ifdef CONFIG_CPU_FREQ
100 static int cpufreq_transition(struct notifier_block *nb,
101 				     unsigned long val, void *data)
102 {
103 	struct tilcdc_drm_private *priv = container_of(nb,
104 			struct tilcdc_drm_private, freq_transition);
105 	if (val == CPUFREQ_POSTCHANGE) {
106 		if (priv->lcd_fck_rate != clk_get_rate(priv->clk)) {
107 			priv->lcd_fck_rate = clk_get_rate(priv->clk);
108 			tilcdc_crtc_update_clk(priv->crtc);
109 		}
110 	}
111 
112 	return 0;
113 }
114 #endif
115 
116 /*
117  * DRM operations:
118  */
119 
120 static int tilcdc_unload(struct drm_device *dev)
121 {
122 	struct tilcdc_drm_private *priv = dev->dev_private;
123 
124 	drm_fbdev_cma_fini(priv->fbdev);
125 	drm_kms_helper_poll_fini(dev);
126 	drm_mode_config_cleanup(dev);
127 	drm_vblank_cleanup(dev);
128 
129 	pm_runtime_get_sync(dev->dev);
130 	drm_irq_uninstall(dev);
131 	pm_runtime_put_sync(dev->dev);
132 
133 #ifdef CONFIG_CPU_FREQ
134 	cpufreq_unregister_notifier(&priv->freq_transition,
135 			CPUFREQ_TRANSITION_NOTIFIER);
136 #endif
137 
138 	if (priv->clk)
139 		clk_put(priv->clk);
140 
141 	if (priv->mmio)
142 		iounmap(priv->mmio);
143 
144 	flush_workqueue(priv->wq);
145 	destroy_workqueue(priv->wq);
146 
147 	dev->dev_private = NULL;
148 
149 	pm_runtime_disable(dev->dev);
150 
151 	kfree(priv);
152 
153 	return 0;
154 }
155 
156 static int tilcdc_load(struct drm_device *dev, unsigned long flags)
157 {
158 	struct platform_device *pdev = dev->platformdev;
159 	struct device_node *node = pdev->dev.of_node;
160 	struct tilcdc_drm_private *priv;
161 	struct tilcdc_module *mod;
162 	struct resource *res;
163 	u32 bpp = 0;
164 	int ret;
165 
166 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
167 	if (!priv) {
168 		dev_err(dev->dev, "failed to allocate private data\n");
169 		return -ENOMEM;
170 	}
171 
172 	dev->dev_private = priv;
173 
174 	priv->wq = alloc_ordered_workqueue("tilcdc", 0);
175 
176 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
177 	if (!res) {
178 		dev_err(dev->dev, "failed to get memory resource\n");
179 		ret = -EINVAL;
180 		goto fail;
181 	}
182 
183 	priv->mmio = ioremap_nocache(res->start, resource_size(res));
184 	if (!priv->mmio) {
185 		dev_err(dev->dev, "failed to ioremap\n");
186 		ret = -ENOMEM;
187 		goto fail;
188 	}
189 
190 	priv->clk = clk_get(dev->dev, "fck");
191 	if (IS_ERR(priv->clk)) {
192 		dev_err(dev->dev, "failed to get functional clock\n");
193 		ret = -ENODEV;
194 		goto fail;
195 	}
196 
197 	priv->disp_clk = clk_get(dev->dev, "dpll_disp_ck");
198 	if (IS_ERR(priv->clk)) {
199 		dev_err(dev->dev, "failed to get display clock\n");
200 		ret = -ENODEV;
201 		goto fail;
202 	}
203 
204 #ifdef CONFIG_CPU_FREQ
205 	priv->lcd_fck_rate = clk_get_rate(priv->clk);
206 	priv->freq_transition.notifier_call = cpufreq_transition;
207 	ret = cpufreq_register_notifier(&priv->freq_transition,
208 			CPUFREQ_TRANSITION_NOTIFIER);
209 	if (ret) {
210 		dev_err(dev->dev, "failed to register cpufreq notifier\n");
211 		goto fail;
212 	}
213 #endif
214 
215 	if (of_property_read_u32(node, "max-bandwidth", &priv->max_bandwidth))
216 		priv->max_bandwidth = TILCDC_DEFAULT_MAX_BANDWIDTH;
217 
218 	DBG("Maximum Bandwidth Value %d", priv->max_bandwidth);
219 
220 	if (of_property_read_u32(node, "ti,max-width", &priv->max_width))
221 		priv->max_width = TILCDC_DEFAULT_MAX_WIDTH;
222 
223 	DBG("Maximum Horizontal Pixel Width Value %dpixels", priv->max_width);
224 
225 	if (of_property_read_u32(node, "ti,max-pixelclock",
226 					&priv->max_pixelclock))
227 		priv->max_pixelclock = TILCDC_DEFAULT_MAX_PIXELCLOCK;
228 
229 	DBG("Maximum Pixel Clock Value %dKHz", priv->max_pixelclock);
230 
231 	pm_runtime_enable(dev->dev);
232 
233 	/* Determine LCD IP Version */
234 	pm_runtime_get_sync(dev->dev);
235 	switch (tilcdc_read(dev, LCDC_PID_REG)) {
236 	case 0x4c100102:
237 		priv->rev = 1;
238 		break;
239 	case 0x4f200800:
240 	case 0x4f201000:
241 		priv->rev = 2;
242 		break;
243 	default:
244 		dev_warn(dev->dev, "Unknown PID Reg value 0x%08x, "
245 				"defaulting to LCD revision 1\n",
246 				tilcdc_read(dev, LCDC_PID_REG));
247 		priv->rev = 1;
248 		break;
249 	}
250 
251 	pm_runtime_put_sync(dev->dev);
252 
253 	ret = modeset_init(dev);
254 	if (ret < 0) {
255 		dev_err(dev->dev, "failed to initialize mode setting\n");
256 		goto fail;
257 	}
258 
259 	ret = drm_vblank_init(dev, 1);
260 	if (ret < 0) {
261 		dev_err(dev->dev, "failed to initialize vblank\n");
262 		goto fail;
263 	}
264 
265 	pm_runtime_get_sync(dev->dev);
266 	ret = drm_irq_install(dev, platform_get_irq(dev->platformdev, 0));
267 	pm_runtime_put_sync(dev->dev);
268 	if (ret < 0) {
269 		dev_err(dev->dev, "failed to install IRQ handler\n");
270 		goto fail;
271 	}
272 
273 	platform_set_drvdata(pdev, dev);
274 
275 
276 	list_for_each_entry(mod, &module_list, list) {
277 		DBG("%s: preferred_bpp: %d", mod->name, mod->preferred_bpp);
278 		bpp = mod->preferred_bpp;
279 		if (bpp > 0)
280 			break;
281 	}
282 
283 	priv->fbdev = drm_fbdev_cma_init(dev, bpp,
284 			dev->mode_config.num_crtc,
285 			dev->mode_config.num_connector);
286 
287 	drm_kms_helper_poll_init(dev);
288 
289 	return 0;
290 
291 fail:
292 	tilcdc_unload(dev);
293 	return ret;
294 }
295 
296 static void tilcdc_preclose(struct drm_device *dev, struct drm_file *file)
297 {
298 	struct tilcdc_drm_private *priv = dev->dev_private;
299 
300 	tilcdc_crtc_cancel_page_flip(priv->crtc, file);
301 }
302 
303 static void tilcdc_lastclose(struct drm_device *dev)
304 {
305 	struct tilcdc_drm_private *priv = dev->dev_private;
306 	drm_fbdev_cma_restore_mode(priv->fbdev);
307 }
308 
309 static irqreturn_t tilcdc_irq(int irq, void *arg)
310 {
311 	struct drm_device *dev = arg;
312 	struct tilcdc_drm_private *priv = dev->dev_private;
313 	return tilcdc_crtc_irq(priv->crtc);
314 }
315 
316 static void tilcdc_irq_preinstall(struct drm_device *dev)
317 {
318 	tilcdc_clear_irqstatus(dev, 0xffffffff);
319 }
320 
321 static int tilcdc_irq_postinstall(struct drm_device *dev)
322 {
323 	struct tilcdc_drm_private *priv = dev->dev_private;
324 
325 	/* enable FIFO underflow irq: */
326 	if (priv->rev == 1)
327 		tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_V1_UNDERFLOW_INT_ENA);
328 	else
329 		tilcdc_set(dev, LCDC_INT_ENABLE_SET_REG, LCDC_V2_UNDERFLOW_INT_ENA);
330 
331 	return 0;
332 }
333 
334 static void tilcdc_irq_uninstall(struct drm_device *dev)
335 {
336 	struct tilcdc_drm_private *priv = dev->dev_private;
337 
338 	/* disable irqs that we might have enabled: */
339 	if (priv->rev == 1) {
340 		tilcdc_clear(dev, LCDC_RASTER_CTRL_REG,
341 				LCDC_V1_UNDERFLOW_INT_ENA | LCDC_V1_PL_INT_ENA);
342 		tilcdc_clear(dev, LCDC_DMA_CTRL_REG, LCDC_V1_END_OF_FRAME_INT_ENA);
343 	} else {
344 		tilcdc_clear(dev, LCDC_INT_ENABLE_SET_REG,
345 			LCDC_V2_UNDERFLOW_INT_ENA | LCDC_V2_PL_INT_ENA |
346 			LCDC_V2_END_OF_FRAME0_INT_ENA | LCDC_V2_END_OF_FRAME1_INT_ENA |
347 			LCDC_FRAME_DONE);
348 	}
349 
350 }
351 
352 static void enable_vblank(struct drm_device *dev, bool enable)
353 {
354 	struct tilcdc_drm_private *priv = dev->dev_private;
355 	u32 reg, mask;
356 
357 	if (priv->rev == 1) {
358 		reg = LCDC_DMA_CTRL_REG;
359 		mask = LCDC_V1_END_OF_FRAME_INT_ENA;
360 	} else {
361 		reg = LCDC_INT_ENABLE_SET_REG;
362 		mask = LCDC_V2_END_OF_FRAME0_INT_ENA |
363 			LCDC_V2_END_OF_FRAME1_INT_ENA | LCDC_FRAME_DONE;
364 	}
365 
366 	if (enable)
367 		tilcdc_set(dev, reg, mask);
368 	else
369 		tilcdc_clear(dev, reg, mask);
370 }
371 
372 static int tilcdc_enable_vblank(struct drm_device *dev, int crtc)
373 {
374 	enable_vblank(dev, true);
375 	return 0;
376 }
377 
378 static void tilcdc_disable_vblank(struct drm_device *dev, int crtc)
379 {
380 	enable_vblank(dev, false);
381 }
382 
383 #if defined(CONFIG_DEBUG_FS) || defined(CONFIG_PM_SLEEP)
384 static const struct {
385 	const char *name;
386 	uint8_t  rev;
387 	uint8_t  save;
388 	uint32_t reg;
389 } registers[] =		{
390 #define REG(rev, save, reg) { #reg, rev, save, reg }
391 		/* exists in revision 1: */
392 		REG(1, false, LCDC_PID_REG),
393 		REG(1, true,  LCDC_CTRL_REG),
394 		REG(1, false, LCDC_STAT_REG),
395 		REG(1, true,  LCDC_RASTER_CTRL_REG),
396 		REG(1, true,  LCDC_RASTER_TIMING_0_REG),
397 		REG(1, true,  LCDC_RASTER_TIMING_1_REG),
398 		REG(1, true,  LCDC_RASTER_TIMING_2_REG),
399 		REG(1, true,  LCDC_DMA_CTRL_REG),
400 		REG(1, true,  LCDC_DMA_FB_BASE_ADDR_0_REG),
401 		REG(1, true,  LCDC_DMA_FB_CEILING_ADDR_0_REG),
402 		REG(1, true,  LCDC_DMA_FB_BASE_ADDR_1_REG),
403 		REG(1, true,  LCDC_DMA_FB_CEILING_ADDR_1_REG),
404 		/* new in revision 2: */
405 		REG(2, false, LCDC_RAW_STAT_REG),
406 		REG(2, false, LCDC_MASKED_STAT_REG),
407 		REG(2, false, LCDC_INT_ENABLE_SET_REG),
408 		REG(2, false, LCDC_INT_ENABLE_CLR_REG),
409 		REG(2, false, LCDC_END_OF_INT_IND_REG),
410 		REG(2, true,  LCDC_CLK_ENABLE_REG),
411 		REG(2, true,  LCDC_INT_ENABLE_SET_REG),
412 #undef REG
413 };
414 #endif
415 
416 #ifdef CONFIG_DEBUG_FS
417 static int tilcdc_regs_show(struct seq_file *m, void *arg)
418 {
419 	struct drm_info_node *node = (struct drm_info_node *) m->private;
420 	struct drm_device *dev = node->minor->dev;
421 	struct tilcdc_drm_private *priv = dev->dev_private;
422 	unsigned i;
423 
424 	pm_runtime_get_sync(dev->dev);
425 
426 	seq_printf(m, "revision: %d\n", priv->rev);
427 
428 	for (i = 0; i < ARRAY_SIZE(registers); i++)
429 		if (priv->rev >= registers[i].rev)
430 			seq_printf(m, "%s:\t %08x\n", registers[i].name,
431 					tilcdc_read(dev, registers[i].reg));
432 
433 	pm_runtime_put_sync(dev->dev);
434 
435 	return 0;
436 }
437 
438 static int tilcdc_mm_show(struct seq_file *m, void *arg)
439 {
440 	struct drm_info_node *node = (struct drm_info_node *) m->private;
441 	struct drm_device *dev = node->minor->dev;
442 	return drm_mm_dump_table(m, &dev->vma_offset_manager->vm_addr_space_mm);
443 }
444 
445 static struct drm_info_list tilcdc_debugfs_list[] = {
446 		{ "regs", tilcdc_regs_show, 0 },
447 		{ "mm",   tilcdc_mm_show,   0 },
448 		{ "fb",   drm_fb_cma_debugfs_show, 0 },
449 };
450 
451 static int tilcdc_debugfs_init(struct drm_minor *minor)
452 {
453 	struct drm_device *dev = minor->dev;
454 	struct tilcdc_module *mod;
455 	int ret;
456 
457 	ret = drm_debugfs_create_files(tilcdc_debugfs_list,
458 			ARRAY_SIZE(tilcdc_debugfs_list),
459 			minor->debugfs_root, minor);
460 
461 	list_for_each_entry(mod, &module_list, list)
462 		if (mod->funcs->debugfs_init)
463 			mod->funcs->debugfs_init(mod, minor);
464 
465 	if (ret) {
466 		dev_err(dev->dev, "could not install tilcdc_debugfs_list\n");
467 		return ret;
468 	}
469 
470 	return ret;
471 }
472 
473 static void tilcdc_debugfs_cleanup(struct drm_minor *minor)
474 {
475 	struct tilcdc_module *mod;
476 	drm_debugfs_remove_files(tilcdc_debugfs_list,
477 			ARRAY_SIZE(tilcdc_debugfs_list), minor);
478 
479 	list_for_each_entry(mod, &module_list, list)
480 		if (mod->funcs->debugfs_cleanup)
481 			mod->funcs->debugfs_cleanup(mod, minor);
482 }
483 #endif
484 
485 static const struct file_operations fops = {
486 	.owner              = THIS_MODULE,
487 	.open               = drm_open,
488 	.release            = drm_release,
489 	.unlocked_ioctl     = drm_ioctl,
490 #ifdef CONFIG_COMPAT
491 	.compat_ioctl       = drm_compat_ioctl,
492 #endif
493 	.poll               = drm_poll,
494 	.read               = drm_read,
495 	.llseek             = no_llseek,
496 	.mmap               = drm_gem_cma_mmap,
497 };
498 
499 static struct drm_driver tilcdc_driver = {
500 	.driver_features    = DRIVER_HAVE_IRQ | DRIVER_GEM | DRIVER_MODESET,
501 	.load               = tilcdc_load,
502 	.unload             = tilcdc_unload,
503 	.preclose           = tilcdc_preclose,
504 	.lastclose          = tilcdc_lastclose,
505 	.irq_handler        = tilcdc_irq,
506 	.irq_preinstall     = tilcdc_irq_preinstall,
507 	.irq_postinstall    = tilcdc_irq_postinstall,
508 	.irq_uninstall      = tilcdc_irq_uninstall,
509 	.get_vblank_counter = drm_vblank_count,
510 	.enable_vblank      = tilcdc_enable_vblank,
511 	.disable_vblank     = tilcdc_disable_vblank,
512 	.gem_free_object    = drm_gem_cma_free_object,
513 	.gem_vm_ops         = &drm_gem_cma_vm_ops,
514 	.dumb_create        = drm_gem_cma_dumb_create,
515 	.dumb_map_offset    = drm_gem_cma_dumb_map_offset,
516 	.dumb_destroy       = drm_gem_dumb_destroy,
517 #ifdef CONFIG_DEBUG_FS
518 	.debugfs_init       = tilcdc_debugfs_init,
519 	.debugfs_cleanup    = tilcdc_debugfs_cleanup,
520 #endif
521 	.fops               = &fops,
522 	.name               = "tilcdc",
523 	.desc               = "TI LCD Controller DRM",
524 	.date               = "20121205",
525 	.major              = 1,
526 	.minor              = 0,
527 };
528 
529 /*
530  * Power management:
531  */
532 
533 #ifdef CONFIG_PM_SLEEP
534 static int tilcdc_pm_suspend(struct device *dev)
535 {
536 	struct drm_device *ddev = dev_get_drvdata(dev);
537 	struct tilcdc_drm_private *priv = ddev->dev_private;
538 	unsigned i, n = 0;
539 
540 	drm_kms_helper_poll_disable(ddev);
541 
542 	/* Save register state: */
543 	for (i = 0; i < ARRAY_SIZE(registers); i++)
544 		if (registers[i].save && (priv->rev >= registers[i].rev))
545 			priv->saved_register[n++] = tilcdc_read(ddev, registers[i].reg);
546 
547 	return 0;
548 }
549 
550 static int tilcdc_pm_resume(struct device *dev)
551 {
552 	struct drm_device *ddev = dev_get_drvdata(dev);
553 	struct tilcdc_drm_private *priv = ddev->dev_private;
554 	unsigned i, n = 0;
555 
556 	/* Restore register state: */
557 	for (i = 0; i < ARRAY_SIZE(registers); i++)
558 		if (registers[i].save && (priv->rev >= registers[i].rev))
559 			tilcdc_write(ddev, registers[i].reg, priv->saved_register[n++]);
560 
561 	drm_kms_helper_poll_enable(ddev);
562 
563 	return 0;
564 }
565 #endif
566 
567 static const struct dev_pm_ops tilcdc_pm_ops = {
568 	SET_SYSTEM_SLEEP_PM_OPS(tilcdc_pm_suspend, tilcdc_pm_resume)
569 };
570 
571 /*
572  * Platform driver:
573  */
574 
575 static int tilcdc_pdev_probe(struct platform_device *pdev)
576 {
577 	/* bail out early if no DT data: */
578 	if (!pdev->dev.of_node) {
579 		dev_err(&pdev->dev, "device-tree data is missing\n");
580 		return -ENXIO;
581 	}
582 
583 	/* defer probing if slave is in deferred probing */
584 	if (slave_probing == true)
585 		return -EPROBE_DEFER;
586 
587 	return drm_platform_init(&tilcdc_driver, pdev);
588 }
589 
590 static int tilcdc_pdev_remove(struct platform_device *pdev)
591 {
592 	drm_put_dev(platform_get_drvdata(pdev));
593 
594 	return 0;
595 }
596 
597 static struct of_device_id tilcdc_of_match[] = {
598 		{ .compatible = "ti,am33xx-tilcdc", },
599 		{ },
600 };
601 MODULE_DEVICE_TABLE(of, tilcdc_of_match);
602 
603 static struct platform_driver tilcdc_platform_driver = {
604 	.probe      = tilcdc_pdev_probe,
605 	.remove     = tilcdc_pdev_remove,
606 	.driver     = {
607 		.owner  = THIS_MODULE,
608 		.name   = "tilcdc",
609 		.pm     = &tilcdc_pm_ops,
610 		.of_match_table = tilcdc_of_match,
611 	},
612 };
613 
614 static int __init tilcdc_drm_init(void)
615 {
616 	DBG("init");
617 	tilcdc_tfp410_init();
618 	tilcdc_slave_init();
619 	tilcdc_panel_init();
620 	return platform_driver_register(&tilcdc_platform_driver);
621 }
622 
623 static void __exit tilcdc_drm_fini(void)
624 {
625 	DBG("fini");
626 	platform_driver_unregister(&tilcdc_platform_driver);
627 	tilcdc_panel_fini();
628 	tilcdc_slave_fini();
629 	tilcdc_tfp410_fini();
630 }
631 
632 module_init(tilcdc_drm_init);
633 module_exit(tilcdc_drm_fini);
634 
635 MODULE_AUTHOR("Rob Clark <robdclark@gmail.com");
636 MODULE_DESCRIPTION("TI LCD Controller DRM Driver");
637 MODULE_LICENSE("GPL");
638