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 #include <linux/gpio/consumer.h>
8 #include <linux/pinctrl/consumer.h>
9 #include <linux/platform_device.h>
10 
11 #include <video/display_timing.h>
12 #include <video/of_display_timing.h>
13 #include <video/videomode.h>
14 
15 #include <drm/drm_atomic_state_helper.h>
16 #include <drm/drm_connector.h>
17 #include <drm/drm_modeset_helper_vtables.h>
18 #include <drm/drm_probe_helper.h>
19 
20 #include "tilcdc_drv.h"
21 #include "tilcdc_panel.h"
22 
23 struct panel_module {
24 	struct tilcdc_module base;
25 	struct tilcdc_panel_info *info;
26 	struct display_timings *timings;
27 	struct backlight_device *backlight;
28 	struct gpio_desc *enable_gpio;
29 };
30 #define to_panel_module(x) container_of(x, struct panel_module, base)
31 
32 
33 /*
34  * Encoder:
35  */
36 
37 struct panel_encoder {
38 	struct drm_encoder base;
39 	struct panel_module *mod;
40 };
41 #define to_panel_encoder(x) container_of(x, struct panel_encoder, base)
42 
43 static void panel_encoder_dpms(struct drm_encoder *encoder, int mode)
44 {
45 	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
46 	struct backlight_device *backlight = panel_encoder->mod->backlight;
47 	struct gpio_desc *gpio = panel_encoder->mod->enable_gpio;
48 
49 	if (backlight) {
50 		backlight->props.power = mode == DRM_MODE_DPMS_ON ?
51 					 FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
52 		backlight_update_status(backlight);
53 	}
54 
55 	if (gpio)
56 		gpiod_set_value_cansleep(gpio,
57 					 mode == DRM_MODE_DPMS_ON ? 1 : 0);
58 }
59 
60 static void panel_encoder_prepare(struct drm_encoder *encoder)
61 {
62 	panel_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
63 }
64 
65 static void panel_encoder_commit(struct drm_encoder *encoder)
66 {
67 	panel_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
68 }
69 
70 static void panel_encoder_mode_set(struct drm_encoder *encoder,
71 		struct drm_display_mode *mode,
72 		struct drm_display_mode *adjusted_mode)
73 {
74 	/* nothing needed */
75 }
76 
77 static const struct drm_encoder_funcs panel_encoder_funcs = {
78 		.destroy        = drm_encoder_cleanup,
79 };
80 
81 static const struct drm_encoder_helper_funcs panel_encoder_helper_funcs = {
82 		.dpms           = panel_encoder_dpms,
83 		.prepare        = panel_encoder_prepare,
84 		.commit         = panel_encoder_commit,
85 		.mode_set       = panel_encoder_mode_set,
86 };
87 
88 static struct drm_encoder *panel_encoder_create(struct drm_device *dev,
89 		struct panel_module *mod)
90 {
91 	struct panel_encoder *panel_encoder;
92 	struct drm_encoder *encoder;
93 	int ret;
94 
95 	panel_encoder = devm_kzalloc(dev->dev, sizeof(*panel_encoder),
96 				     GFP_KERNEL);
97 	if (!panel_encoder)
98 		return NULL;
99 
100 	panel_encoder->mod = mod;
101 
102 	encoder = &panel_encoder->base;
103 	encoder->possible_crtcs = 1;
104 
105 	ret = drm_encoder_init(dev, encoder, &panel_encoder_funcs,
106 			DRM_MODE_ENCODER_LVDS, NULL);
107 	if (ret < 0)
108 		goto fail;
109 
110 	drm_encoder_helper_add(encoder, &panel_encoder_helper_funcs);
111 
112 	return encoder;
113 
114 fail:
115 	drm_encoder_cleanup(encoder);
116 	return NULL;
117 }
118 
119 /*
120  * Connector:
121  */
122 
123 struct panel_connector {
124 	struct drm_connector base;
125 
126 	struct drm_encoder *encoder;  /* our connected encoder */
127 	struct panel_module *mod;
128 };
129 #define to_panel_connector(x) container_of(x, struct panel_connector, base)
130 
131 
132 static void panel_connector_destroy(struct drm_connector *connector)
133 {
134 	drm_connector_unregister(connector);
135 	drm_connector_cleanup(connector);
136 }
137 
138 static int panel_connector_get_modes(struct drm_connector *connector)
139 {
140 	struct drm_device *dev = connector->dev;
141 	struct panel_connector *panel_connector = to_panel_connector(connector);
142 	struct display_timings *timings = panel_connector->mod->timings;
143 	int i;
144 
145 	for (i = 0; i < timings->num_timings; i++) {
146 		struct drm_display_mode *mode = drm_mode_create(dev);
147 		struct videomode vm;
148 
149 		if (videomode_from_timings(timings, &vm, i))
150 			break;
151 
152 		drm_display_mode_from_videomode(&vm, mode);
153 
154 		mode->type = DRM_MODE_TYPE_DRIVER;
155 
156 		if (timings->native_mode == i)
157 			mode->type |= DRM_MODE_TYPE_PREFERRED;
158 
159 		drm_mode_set_name(mode);
160 		drm_mode_probed_add(connector, mode);
161 	}
162 
163 	return i;
164 }
165 
166 static int panel_connector_mode_valid(struct drm_connector *connector,
167 		  struct drm_display_mode *mode)
168 {
169 	struct tilcdc_drm_private *priv = connector->dev->dev_private;
170 	/* our only constraints are what the crtc can generate: */
171 	return tilcdc_crtc_mode_valid(priv->crtc, mode);
172 }
173 
174 static struct drm_encoder *panel_connector_best_encoder(
175 		struct drm_connector *connector)
176 {
177 	struct panel_connector *panel_connector = to_panel_connector(connector);
178 	return panel_connector->encoder;
179 }
180 
181 static const struct drm_connector_funcs panel_connector_funcs = {
182 	.destroy            = panel_connector_destroy,
183 	.fill_modes         = drm_helper_probe_single_connector_modes,
184 	.reset              = drm_atomic_helper_connector_reset,
185 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
186 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
187 };
188 
189 static const struct drm_connector_helper_funcs panel_connector_helper_funcs = {
190 	.get_modes          = panel_connector_get_modes,
191 	.mode_valid         = panel_connector_mode_valid,
192 	.best_encoder       = panel_connector_best_encoder,
193 };
194 
195 static struct drm_connector *panel_connector_create(struct drm_device *dev,
196 		struct panel_module *mod, struct drm_encoder *encoder)
197 {
198 	struct panel_connector *panel_connector;
199 	struct drm_connector *connector;
200 	int ret;
201 
202 	panel_connector = devm_kzalloc(dev->dev, sizeof(*panel_connector),
203 				       GFP_KERNEL);
204 	if (!panel_connector)
205 		return NULL;
206 
207 	panel_connector->encoder = encoder;
208 	panel_connector->mod = mod;
209 
210 	connector = &panel_connector->base;
211 
212 	drm_connector_init(dev, connector, &panel_connector_funcs,
213 			DRM_MODE_CONNECTOR_LVDS);
214 	drm_connector_helper_add(connector, &panel_connector_helper_funcs);
215 
216 	connector->interlace_allowed = 0;
217 	connector->doublescan_allowed = 0;
218 
219 	ret = drm_connector_attach_encoder(connector, encoder);
220 	if (ret)
221 		goto fail;
222 
223 	return connector;
224 
225 fail:
226 	panel_connector_destroy(connector);
227 	return NULL;
228 }
229 
230 /*
231  * Module:
232  */
233 
234 static int panel_modeset_init(struct tilcdc_module *mod, struct drm_device *dev)
235 {
236 	struct panel_module *panel_mod = to_panel_module(mod);
237 	struct tilcdc_drm_private *priv = dev->dev_private;
238 	struct drm_encoder *encoder;
239 	struct drm_connector *connector;
240 
241 	encoder = panel_encoder_create(dev, panel_mod);
242 	if (!encoder)
243 		return -ENOMEM;
244 
245 	connector = panel_connector_create(dev, panel_mod, encoder);
246 	if (!connector)
247 		return -ENOMEM;
248 
249 	priv->encoders[priv->num_encoders++] = encoder;
250 	priv->connectors[priv->num_connectors++] = connector;
251 
252 	tilcdc_crtc_set_panel_info(priv->crtc,
253 				   to_panel_encoder(encoder)->mod->info);
254 
255 	return 0;
256 }
257 
258 static const struct tilcdc_module_ops panel_module_ops = {
259 		.modeset_init = panel_modeset_init,
260 };
261 
262 /*
263  * Device:
264  */
265 
266 /* maybe move this somewhere common if it is needed by other outputs? */
267 static struct tilcdc_panel_info *of_get_panel_info(struct device_node *np)
268 {
269 	struct device_node *info_np;
270 	struct tilcdc_panel_info *info;
271 	int ret = 0;
272 
273 	if (!np) {
274 		pr_err("%s: no devicenode given\n", __func__);
275 		return NULL;
276 	}
277 
278 	info_np = of_get_child_by_name(np, "panel-info");
279 	if (!info_np) {
280 		pr_err("%s: could not find panel-info node\n", __func__);
281 		return NULL;
282 	}
283 
284 	info = kzalloc(sizeof(*info), GFP_KERNEL);
285 	if (!info)
286 		goto put_node;
287 
288 	ret |= of_property_read_u32(info_np, "ac-bias", &info->ac_bias);
289 	ret |= of_property_read_u32(info_np, "ac-bias-intrpt", &info->ac_bias_intrpt);
290 	ret |= of_property_read_u32(info_np, "dma-burst-sz", &info->dma_burst_sz);
291 	ret |= of_property_read_u32(info_np, "bpp", &info->bpp);
292 	ret |= of_property_read_u32(info_np, "fdd", &info->fdd);
293 	ret |= of_property_read_u32(info_np, "sync-edge", &info->sync_edge);
294 	ret |= of_property_read_u32(info_np, "sync-ctrl", &info->sync_ctrl);
295 	ret |= of_property_read_u32(info_np, "raster-order", &info->raster_order);
296 	ret |= of_property_read_u32(info_np, "fifo-th", &info->fifo_th);
297 
298 	/* optional: */
299 	info->tft_alt_mode      = of_property_read_bool(info_np, "tft-alt-mode");
300 	info->invert_pxl_clk    = of_property_read_bool(info_np, "invert-pxl-clk");
301 
302 	if (ret) {
303 		pr_err("%s: error reading panel-info properties\n", __func__);
304 		kfree(info);
305 		info = NULL;
306 	}
307 
308 put_node:
309 	of_node_put(info_np);
310 	return info;
311 }
312 
313 static int panel_probe(struct platform_device *pdev)
314 {
315 	struct device_node *bl_node, *node = pdev->dev.of_node;
316 	struct panel_module *panel_mod;
317 	struct tilcdc_module *mod;
318 	struct pinctrl *pinctrl;
319 	int ret;
320 
321 	/* bail out early if no DT data: */
322 	if (!node) {
323 		dev_err(&pdev->dev, "device-tree data is missing\n");
324 		return -ENXIO;
325 	}
326 
327 	panel_mod = devm_kzalloc(&pdev->dev, sizeof(*panel_mod), GFP_KERNEL);
328 	if (!panel_mod)
329 		return -ENOMEM;
330 
331 	bl_node = of_parse_phandle(node, "backlight", 0);
332 	if (bl_node) {
333 		panel_mod->backlight = of_find_backlight_by_node(bl_node);
334 		of_node_put(bl_node);
335 
336 		if (!panel_mod->backlight)
337 			return -EPROBE_DEFER;
338 
339 		dev_info(&pdev->dev, "found backlight\n");
340 	}
341 
342 	panel_mod->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
343 							 GPIOD_OUT_LOW);
344 	if (IS_ERR(panel_mod->enable_gpio)) {
345 		ret = PTR_ERR(panel_mod->enable_gpio);
346 		dev_err(&pdev->dev, "failed to request enable GPIO\n");
347 		goto fail_backlight;
348 	}
349 
350 	if (panel_mod->enable_gpio)
351 		dev_info(&pdev->dev, "found enable GPIO\n");
352 
353 	mod = &panel_mod->base;
354 	pdev->dev.platform_data = mod;
355 
356 	tilcdc_module_init(mod, "panel", &panel_module_ops);
357 
358 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
359 	if (IS_ERR(pinctrl))
360 		dev_warn(&pdev->dev, "pins are not configured\n");
361 
362 	panel_mod->timings = of_get_display_timings(node);
363 	if (!panel_mod->timings) {
364 		dev_err(&pdev->dev, "could not get panel timings\n");
365 		ret = -EINVAL;
366 		goto fail_free;
367 	}
368 
369 	panel_mod->info = of_get_panel_info(node);
370 	if (!panel_mod->info) {
371 		dev_err(&pdev->dev, "could not get panel info\n");
372 		ret = -EINVAL;
373 		goto fail_timings;
374 	}
375 
376 	return 0;
377 
378 fail_timings:
379 	display_timings_release(panel_mod->timings);
380 
381 fail_free:
382 	tilcdc_module_cleanup(mod);
383 
384 fail_backlight:
385 	if (panel_mod->backlight)
386 		put_device(&panel_mod->backlight->dev);
387 	return ret;
388 }
389 
390 static int panel_remove(struct platform_device *pdev)
391 {
392 	struct tilcdc_module *mod = dev_get_platdata(&pdev->dev);
393 	struct panel_module *panel_mod = to_panel_module(mod);
394 	struct backlight_device *backlight = panel_mod->backlight;
395 
396 	if (backlight)
397 		put_device(&backlight->dev);
398 
399 	display_timings_release(panel_mod->timings);
400 
401 	tilcdc_module_cleanup(mod);
402 	kfree(panel_mod->info);
403 
404 	return 0;
405 }
406 
407 static const struct of_device_id panel_of_match[] = {
408 		{ .compatible = "ti,tilcdc,panel", },
409 		{ },
410 };
411 
412 struct platform_driver panel_driver = {
413 	.probe = panel_probe,
414 	.remove = panel_remove,
415 	.driver = {
416 		.owner = THIS_MODULE,
417 		.name = "tilcdc-panel",
418 		.of_match_table = panel_of_match,
419 	},
420 };
421 
422 int __init tilcdc_panel_init(void)
423 {
424 	return platform_driver_register(&panel_driver);
425 }
426 
427 void __exit tilcdc_panel_fini(void)
428 {
429 	platform_driver_unregister(&panel_driver);
430 }
431