1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 Texas Instruments
4  * Author: Rob Clark <robdclark@gmail.com>
5  */
6 
7 /* LCDC DRM driver, based on da8xx-fb */
8 
9 #include <linux/component.h>
10 #include <linux/mod_devicetable.h>
11 #include <linux/module.h>
12 #include <linux/pinctrl/consumer.h>
13 #include <linux/platform_device.h>
14 #include <linux/pm_runtime.h>
15 
16 #include <drm/drm_atomic_helper.h>
17 #include <drm/drm_debugfs.h>
18 #include <drm/drm_drv.h>
19 #include <drm/drm_fbdev_dma.h>
20 #include <drm/drm_fourcc.h>
21 #include <drm/drm_gem_dma_helper.h>
22 #include <drm/drm_gem_framebuffer_helper.h>
23 #include <drm/drm_mm.h>
24 #include <drm/drm_probe_helper.h>
25 #include <drm/drm_vblank.h>
26 
27 
28 #include "tilcdc_drv.h"
29 #include "tilcdc_external.h"
30 #include "tilcdc_panel.h"
31 #include "tilcdc_regs.h"
32 
33 static LIST_HEAD(module_list);
34 
35 static const u32 tilcdc_rev1_formats[] = { DRM_FORMAT_RGB565 };
36 
37 static const u32 tilcdc_straight_formats[] = { DRM_FORMAT_RGB565,
38 					       DRM_FORMAT_BGR888,
39 					       DRM_FORMAT_XBGR8888 };
40 
41 static const u32 tilcdc_crossed_formats[] = { DRM_FORMAT_BGR565,
42 					      DRM_FORMAT_RGB888,
43 					      DRM_FORMAT_XRGB8888 };
44 
45 static const u32 tilcdc_legacy_formats[] = { DRM_FORMAT_RGB565,
46 					     DRM_FORMAT_RGB888,
47 					     DRM_FORMAT_XRGB8888 };
48 
49 void tilcdc_module_init(struct tilcdc_module *mod, const char *name,
50 		const struct tilcdc_module_ops *funcs)
51 {
52 	mod->name = name;
53 	mod->funcs = funcs;
54 	INIT_LIST_HEAD(&mod->list);
55 	list_add(&mod->list, &module_list);
56 }
57 
58 void tilcdc_module_cleanup(struct tilcdc_module *mod)
59 {
60 	list_del(&mod->list);
61 }
62 
63 static int tilcdc_atomic_check(struct drm_device *dev,
64 			       struct drm_atomic_state *state)
65 {
66 	int ret;
67 
68 	ret = drm_atomic_helper_check_modeset(dev, state);
69 	if (ret)
70 		return ret;
71 
72 	ret = drm_atomic_helper_check_planes(dev, state);
73 	if (ret)
74 		return ret;
75 
76 	/*
77 	 * tilcdc ->atomic_check can update ->mode_changed if pixel format
78 	 * changes, hence will we check modeset changes again.
79 	 */
80 	ret = drm_atomic_helper_check_modeset(dev, state);
81 	if (ret)
82 		return ret;
83 
84 	return ret;
85 }
86 
87 static const struct drm_mode_config_funcs mode_config_funcs = {
88 	.fb_create = drm_gem_fb_create,
89 	.atomic_check = tilcdc_atomic_check,
90 	.atomic_commit = drm_atomic_helper_commit,
91 };
92 
93 static void modeset_init(struct drm_device *dev)
94 {
95 	struct tilcdc_drm_private *priv = dev->dev_private;
96 	struct tilcdc_module *mod;
97 
98 	list_for_each_entry(mod, &module_list, list) {
99 		DBG("loading module: %s", mod->name);
100 		mod->funcs->modeset_init(mod, dev);
101 	}
102 
103 	dev->mode_config.min_width = 0;
104 	dev->mode_config.min_height = 0;
105 	dev->mode_config.max_width = priv->max_width;
106 	dev->mode_config.max_height = 2048;
107 	dev->mode_config.funcs = &mode_config_funcs;
108 }
109 
110 #ifdef CONFIG_CPU_FREQ
111 static int cpufreq_transition(struct notifier_block *nb,
112 				     unsigned long val, void *data)
113 {
114 	struct tilcdc_drm_private *priv = container_of(nb,
115 			struct tilcdc_drm_private, freq_transition);
116 
117 	if (val == CPUFREQ_POSTCHANGE)
118 		tilcdc_crtc_update_clk(priv->crtc);
119 
120 	return 0;
121 }
122 #endif
123 
124 static irqreturn_t tilcdc_irq(int irq, void *arg)
125 {
126 	struct drm_device *dev = arg;
127 	struct tilcdc_drm_private *priv = dev->dev_private;
128 
129 	return tilcdc_crtc_irq(priv->crtc);
130 }
131 
132 static int tilcdc_irq_install(struct drm_device *dev, unsigned int irq)
133 {
134 	struct tilcdc_drm_private *priv = dev->dev_private;
135 	int ret;
136 
137 	ret = request_irq(irq, tilcdc_irq, 0, dev->driver->name, dev);
138 	if (ret)
139 		return ret;
140 
141 	priv->irq_enabled = false;
142 
143 	return 0;
144 }
145 
146 static void tilcdc_irq_uninstall(struct drm_device *dev)
147 {
148 	struct tilcdc_drm_private *priv = dev->dev_private;
149 
150 	if (!priv->irq_enabled)
151 		return;
152 
153 	free_irq(priv->irq, dev);
154 	priv->irq_enabled = false;
155 }
156 
157 /*
158  * DRM operations:
159  */
160 
161 static void tilcdc_fini(struct drm_device *dev)
162 {
163 	struct tilcdc_drm_private *priv = dev->dev_private;
164 
165 #ifdef CONFIG_CPU_FREQ
166 	if (priv->freq_transition.notifier_call)
167 		cpufreq_unregister_notifier(&priv->freq_transition,
168 					    CPUFREQ_TRANSITION_NOTIFIER);
169 #endif
170 
171 	if (priv->crtc)
172 		tilcdc_crtc_shutdown(priv->crtc);
173 
174 	if (priv->is_registered)
175 		drm_dev_unregister(dev);
176 
177 	drm_kms_helper_poll_fini(dev);
178 	tilcdc_irq_uninstall(dev);
179 	drm_mode_config_cleanup(dev);
180 
181 	if (priv->clk)
182 		clk_put(priv->clk);
183 
184 	if (priv->mmio)
185 		iounmap(priv->mmio);
186 
187 	if (priv->wq)
188 		destroy_workqueue(priv->wq);
189 
190 	dev->dev_private = NULL;
191 
192 	pm_runtime_disable(dev->dev);
193 
194 	drm_dev_put(dev);
195 }
196 
197 static int tilcdc_init(const struct drm_driver *ddrv, struct device *dev)
198 {
199 	struct drm_device *ddev;
200 	struct platform_device *pdev = to_platform_device(dev);
201 	struct device_node *node = dev->of_node;
202 	struct tilcdc_drm_private *priv;
203 	struct resource *res;
204 	u32 bpp = 0;
205 	int ret;
206 
207 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
208 	if (!priv)
209 		return -ENOMEM;
210 
211 	ddev = drm_dev_alloc(ddrv, dev);
212 	if (IS_ERR(ddev))
213 		return PTR_ERR(ddev);
214 
215 	ddev->dev_private = priv;
216 	platform_set_drvdata(pdev, ddev);
217 	drm_mode_config_init(ddev);
218 
219 	priv->is_componentized =
220 		tilcdc_get_external_components(dev, NULL) > 0;
221 
222 	priv->wq = alloc_ordered_workqueue("tilcdc", 0);
223 	if (!priv->wq) {
224 		ret = -ENOMEM;
225 		goto init_failed;
226 	}
227 
228 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
229 	if (!res) {
230 		dev_err(dev, "failed to get memory resource\n");
231 		ret = -EINVAL;
232 		goto init_failed;
233 	}
234 
235 	priv->mmio = ioremap(res->start, resource_size(res));
236 	if (!priv->mmio) {
237 		dev_err(dev, "failed to ioremap\n");
238 		ret = -ENOMEM;
239 		goto init_failed;
240 	}
241 
242 	priv->clk = clk_get(dev, "fck");
243 	if (IS_ERR(priv->clk)) {
244 		dev_err(dev, "failed to get functional clock\n");
245 		ret = -ENODEV;
246 		goto init_failed;
247 	}
248 
249 	pm_runtime_enable(dev);
250 
251 	/* Determine LCD IP Version */
252 	pm_runtime_get_sync(dev);
253 	switch (tilcdc_read(ddev, LCDC_PID_REG)) {
254 	case 0x4c100102:
255 		priv->rev = 1;
256 		break;
257 	case 0x4f200800:
258 	case 0x4f201000:
259 		priv->rev = 2;
260 		break;
261 	default:
262 		dev_warn(dev, "Unknown PID Reg value 0x%08x, "
263 			"defaulting to LCD revision 1\n",
264 			tilcdc_read(ddev, LCDC_PID_REG));
265 		priv->rev = 1;
266 		break;
267 	}
268 
269 	pm_runtime_put_sync(dev);
270 
271 	if (priv->rev == 1) {
272 		DBG("Revision 1 LCDC supports only RGB565 format");
273 		priv->pixelformats = tilcdc_rev1_formats;
274 		priv->num_pixelformats = ARRAY_SIZE(tilcdc_rev1_formats);
275 		bpp = 16;
276 	} else {
277 		const char *str = "\0";
278 
279 		of_property_read_string(node, "blue-and-red-wiring", &str);
280 		if (0 == strcmp(str, "crossed")) {
281 			DBG("Configured for crossed blue and red wires");
282 			priv->pixelformats = tilcdc_crossed_formats;
283 			priv->num_pixelformats =
284 				ARRAY_SIZE(tilcdc_crossed_formats);
285 			bpp = 32; /* Choose bpp with RGB support for fbdef */
286 		} else if (0 == strcmp(str, "straight")) {
287 			DBG("Configured for straight blue and red wires");
288 			priv->pixelformats = tilcdc_straight_formats;
289 			priv->num_pixelformats =
290 				ARRAY_SIZE(tilcdc_straight_formats);
291 			bpp = 16; /* Choose bpp with RGB support for fbdef */
292 		} else {
293 			DBG("Blue and red wiring '%s' unknown, use legacy mode",
294 			    str);
295 			priv->pixelformats = tilcdc_legacy_formats;
296 			priv->num_pixelformats =
297 				ARRAY_SIZE(tilcdc_legacy_formats);
298 			bpp = 16; /* This is just a guess */
299 		}
300 	}
301 
302 	if (of_property_read_u32(node, "max-bandwidth", &priv->max_bandwidth))
303 		priv->max_bandwidth = TILCDC_DEFAULT_MAX_BANDWIDTH;
304 
305 	DBG("Maximum Bandwidth Value %d", priv->max_bandwidth);
306 
307 	if (of_property_read_u32(node, "max-width", &priv->max_width)) {
308 		if (priv->rev == 1)
309 			priv->max_width = TILCDC_DEFAULT_MAX_WIDTH_V1;
310 		else
311 			priv->max_width = TILCDC_DEFAULT_MAX_WIDTH_V2;
312 	}
313 
314 	DBG("Maximum Horizontal Pixel Width Value %dpixels", priv->max_width);
315 
316 	if (of_property_read_u32(node, "max-pixelclock",
317 				 &priv->max_pixelclock))
318 		priv->max_pixelclock = TILCDC_DEFAULT_MAX_PIXELCLOCK;
319 
320 	DBG("Maximum Pixel Clock Value %dKHz", priv->max_pixelclock);
321 
322 	ret = tilcdc_crtc_create(ddev);
323 	if (ret < 0) {
324 		dev_err(dev, "failed to create crtc\n");
325 		goto init_failed;
326 	}
327 	modeset_init(ddev);
328 
329 #ifdef CONFIG_CPU_FREQ
330 	priv->freq_transition.notifier_call = cpufreq_transition;
331 	ret = cpufreq_register_notifier(&priv->freq_transition,
332 			CPUFREQ_TRANSITION_NOTIFIER);
333 	if (ret) {
334 		dev_err(dev, "failed to register cpufreq notifier\n");
335 		priv->freq_transition.notifier_call = NULL;
336 		goto init_failed;
337 	}
338 #endif
339 
340 	if (priv->is_componentized) {
341 		ret = component_bind_all(dev, ddev);
342 		if (ret < 0)
343 			goto init_failed;
344 
345 		ret = tilcdc_add_component_encoder(ddev);
346 		if (ret < 0)
347 			goto init_failed;
348 	} else {
349 		ret = tilcdc_attach_external_device(ddev);
350 		if (ret)
351 			goto init_failed;
352 	}
353 
354 	if (!priv->external_connector &&
355 	    ((priv->num_encoders == 0) || (priv->num_connectors == 0))) {
356 		dev_err(dev, "no encoders/connectors found\n");
357 		ret = -EPROBE_DEFER;
358 		goto init_failed;
359 	}
360 
361 	ret = drm_vblank_init(ddev, 1);
362 	if (ret < 0) {
363 		dev_err(dev, "failed to initialize vblank\n");
364 		goto init_failed;
365 	}
366 
367 	ret = platform_get_irq(pdev, 0);
368 	if (ret < 0)
369 		goto init_failed;
370 	priv->irq = ret;
371 
372 	ret = tilcdc_irq_install(ddev, priv->irq);
373 	if (ret < 0) {
374 		dev_err(dev, "failed to install IRQ handler\n");
375 		goto init_failed;
376 	}
377 
378 	drm_mode_config_reset(ddev);
379 
380 	drm_kms_helper_poll_init(ddev);
381 
382 	ret = drm_dev_register(ddev, 0);
383 	if (ret)
384 		goto init_failed;
385 	priv->is_registered = true;
386 
387 	drm_fbdev_dma_setup(ddev, bpp);
388 	return 0;
389 
390 init_failed:
391 	tilcdc_fini(ddev);
392 
393 	return ret;
394 }
395 
396 #if defined(CONFIG_DEBUG_FS)
397 static const struct {
398 	const char *name;
399 	uint8_t  rev;
400 	uint8_t  save;
401 	uint32_t reg;
402 } registers[] =		{
403 #define REG(rev, save, reg) { #reg, rev, save, reg }
404 		/* exists in revision 1: */
405 		REG(1, false, LCDC_PID_REG),
406 		REG(1, true,  LCDC_CTRL_REG),
407 		REG(1, false, LCDC_STAT_REG),
408 		REG(1, true,  LCDC_RASTER_CTRL_REG),
409 		REG(1, true,  LCDC_RASTER_TIMING_0_REG),
410 		REG(1, true,  LCDC_RASTER_TIMING_1_REG),
411 		REG(1, true,  LCDC_RASTER_TIMING_2_REG),
412 		REG(1, true,  LCDC_DMA_CTRL_REG),
413 		REG(1, true,  LCDC_DMA_FB_BASE_ADDR_0_REG),
414 		REG(1, true,  LCDC_DMA_FB_CEILING_ADDR_0_REG),
415 		REG(1, true,  LCDC_DMA_FB_BASE_ADDR_1_REG),
416 		REG(1, true,  LCDC_DMA_FB_CEILING_ADDR_1_REG),
417 		/* new in revision 2: */
418 		REG(2, false, LCDC_RAW_STAT_REG),
419 		REG(2, false, LCDC_MASKED_STAT_REG),
420 		REG(2, true, LCDC_INT_ENABLE_SET_REG),
421 		REG(2, false, LCDC_INT_ENABLE_CLR_REG),
422 		REG(2, false, LCDC_END_OF_INT_IND_REG),
423 		REG(2, true,  LCDC_CLK_ENABLE_REG),
424 #undef REG
425 };
426 
427 #endif
428 
429 #ifdef CONFIG_DEBUG_FS
430 static int tilcdc_regs_show(struct seq_file *m, void *arg)
431 {
432 	struct drm_info_node *node = (struct drm_info_node *) m->private;
433 	struct drm_device *dev = node->minor->dev;
434 	struct tilcdc_drm_private *priv = dev->dev_private;
435 	unsigned i;
436 
437 	pm_runtime_get_sync(dev->dev);
438 
439 	seq_printf(m, "revision: %d\n", priv->rev);
440 
441 	for (i = 0; i < ARRAY_SIZE(registers); i++)
442 		if (priv->rev >= registers[i].rev)
443 			seq_printf(m, "%s:\t %08x\n", registers[i].name,
444 					tilcdc_read(dev, registers[i].reg));
445 
446 	pm_runtime_put_sync(dev->dev);
447 
448 	return 0;
449 }
450 
451 static int tilcdc_mm_show(struct seq_file *m, void *arg)
452 {
453 	struct drm_info_node *node = (struct drm_info_node *) m->private;
454 	struct drm_device *dev = node->minor->dev;
455 	struct drm_printer p = drm_seq_file_printer(m);
456 	drm_mm_print(&dev->vma_offset_manager->vm_addr_space_mm, &p);
457 	return 0;
458 }
459 
460 static struct drm_info_list tilcdc_debugfs_list[] = {
461 		{ "regs", tilcdc_regs_show, 0, NULL },
462 		{ "mm",   tilcdc_mm_show,   0, NULL },
463 };
464 
465 static void tilcdc_debugfs_init(struct drm_minor *minor)
466 {
467 	struct tilcdc_module *mod;
468 
469 	drm_debugfs_create_files(tilcdc_debugfs_list,
470 				 ARRAY_SIZE(tilcdc_debugfs_list),
471 				 minor->debugfs_root, minor);
472 
473 	list_for_each_entry(mod, &module_list, list)
474 		if (mod->funcs->debugfs_init)
475 			mod->funcs->debugfs_init(mod, minor);
476 }
477 #endif
478 
479 DEFINE_DRM_GEM_DMA_FOPS(fops);
480 
481 static const struct drm_driver tilcdc_driver = {
482 	.driver_features    = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
483 	DRM_GEM_DMA_DRIVER_OPS,
484 #ifdef CONFIG_DEBUG_FS
485 	.debugfs_init       = tilcdc_debugfs_init,
486 #endif
487 	.fops               = &fops,
488 	.name               = "tilcdc",
489 	.desc               = "TI LCD Controller DRM",
490 	.date               = "20121205",
491 	.major              = 1,
492 	.minor              = 0,
493 };
494 
495 /*
496  * Power management:
497  */
498 
499 static int tilcdc_pm_suspend(struct device *dev)
500 {
501 	struct drm_device *ddev = dev_get_drvdata(dev);
502 	int ret = 0;
503 
504 	ret = drm_mode_config_helper_suspend(ddev);
505 
506 	/* Select sleep pin state */
507 	pinctrl_pm_select_sleep_state(dev);
508 
509 	return ret;
510 }
511 
512 static int tilcdc_pm_resume(struct device *dev)
513 {
514 	struct drm_device *ddev = dev_get_drvdata(dev);
515 
516 	/* Select default pin state */
517 	pinctrl_pm_select_default_state(dev);
518 	return  drm_mode_config_helper_resume(ddev);
519 }
520 
521 static DEFINE_SIMPLE_DEV_PM_OPS(tilcdc_pm_ops,
522 				tilcdc_pm_suspend, tilcdc_pm_resume);
523 
524 /*
525  * Platform driver:
526  */
527 static int tilcdc_bind(struct device *dev)
528 {
529 	return tilcdc_init(&tilcdc_driver, dev);
530 }
531 
532 static void tilcdc_unbind(struct device *dev)
533 {
534 	struct drm_device *ddev = dev_get_drvdata(dev);
535 
536 	/* Check if a subcomponent has already triggered the unloading. */
537 	if (!ddev->dev_private)
538 		return;
539 
540 	tilcdc_fini(dev_get_drvdata(dev));
541 }
542 
543 static const struct component_master_ops tilcdc_comp_ops = {
544 	.bind = tilcdc_bind,
545 	.unbind = tilcdc_unbind,
546 };
547 
548 static int tilcdc_pdev_probe(struct platform_device *pdev)
549 {
550 	struct component_match *match = NULL;
551 	int ret;
552 
553 	/* bail out early if no DT data: */
554 	if (!pdev->dev.of_node) {
555 		dev_err(&pdev->dev, "device-tree data is missing\n");
556 		return -ENXIO;
557 	}
558 
559 	ret = tilcdc_get_external_components(&pdev->dev, &match);
560 	if (ret < 0)
561 		return ret;
562 	else if (ret == 0)
563 		return tilcdc_init(&tilcdc_driver, &pdev->dev);
564 	else
565 		return component_master_add_with_match(&pdev->dev,
566 						       &tilcdc_comp_ops,
567 						       match);
568 }
569 
570 static int tilcdc_pdev_remove(struct platform_device *pdev)
571 {
572 	int ret;
573 
574 	ret = tilcdc_get_external_components(&pdev->dev, NULL);
575 	if (ret < 0)
576 		return ret;
577 	else if (ret == 0)
578 		tilcdc_fini(platform_get_drvdata(pdev));
579 	else
580 		component_master_del(&pdev->dev, &tilcdc_comp_ops);
581 
582 	return 0;
583 }
584 
585 static const struct of_device_id tilcdc_of_match[] = {
586 		{ .compatible = "ti,am33xx-tilcdc", },
587 		{ .compatible = "ti,da850-tilcdc", },
588 		{ },
589 };
590 MODULE_DEVICE_TABLE(of, tilcdc_of_match);
591 
592 static struct platform_driver tilcdc_platform_driver = {
593 	.probe      = tilcdc_pdev_probe,
594 	.remove     = tilcdc_pdev_remove,
595 	.driver     = {
596 		.name   = "tilcdc",
597 		.pm     = pm_sleep_ptr(&tilcdc_pm_ops),
598 		.of_match_table = tilcdc_of_match,
599 	},
600 };
601 
602 static int __init tilcdc_drm_init(void)
603 {
604 	if (drm_firmware_drivers_only())
605 		return -ENODEV;
606 
607 	DBG("init");
608 	tilcdc_panel_init();
609 	return platform_driver_register(&tilcdc_platform_driver);
610 }
611 
612 static void __exit tilcdc_drm_fini(void)
613 {
614 	DBG("fini");
615 	platform_driver_unregister(&tilcdc_platform_driver);
616 	tilcdc_panel_fini();
617 }
618 
619 module_init(tilcdc_drm_init);
620 module_exit(tilcdc_drm_fini);
621 
622 MODULE_AUTHOR("Rob Clark <robdclark@gmail.com");
623 MODULE_DESCRIPTION("TI LCD Controller DRM Driver");
624 MODULE_LICENSE("GPL");
625