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 struct drm_encoder *panel_connector_best_encoder(
167 		struct drm_connector *connector)
168 {
169 	struct panel_connector *panel_connector = to_panel_connector(connector);
170 	return panel_connector->encoder;
171 }
172 
173 static const struct drm_connector_funcs panel_connector_funcs = {
174 	.destroy            = panel_connector_destroy,
175 	.fill_modes         = drm_helper_probe_single_connector_modes,
176 	.reset              = drm_atomic_helper_connector_reset,
177 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
178 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
179 };
180 
181 static const struct drm_connector_helper_funcs panel_connector_helper_funcs = {
182 	.get_modes          = panel_connector_get_modes,
183 	.best_encoder       = panel_connector_best_encoder,
184 };
185 
186 static struct drm_connector *panel_connector_create(struct drm_device *dev,
187 		struct panel_module *mod, struct drm_encoder *encoder)
188 {
189 	struct panel_connector *panel_connector;
190 	struct drm_connector *connector;
191 	int ret;
192 
193 	panel_connector = devm_kzalloc(dev->dev, sizeof(*panel_connector),
194 				       GFP_KERNEL);
195 	if (!panel_connector)
196 		return NULL;
197 
198 	panel_connector->encoder = encoder;
199 	panel_connector->mod = mod;
200 
201 	connector = &panel_connector->base;
202 
203 	drm_connector_init(dev, connector, &panel_connector_funcs,
204 			DRM_MODE_CONNECTOR_LVDS);
205 	drm_connector_helper_add(connector, &panel_connector_helper_funcs);
206 
207 	connector->interlace_allowed = 0;
208 	connector->doublescan_allowed = 0;
209 
210 	ret = drm_connector_attach_encoder(connector, encoder);
211 	if (ret)
212 		goto fail;
213 
214 	return connector;
215 
216 fail:
217 	panel_connector_destroy(connector);
218 	return NULL;
219 }
220 
221 /*
222  * Module:
223  */
224 
225 static int panel_modeset_init(struct tilcdc_module *mod, struct drm_device *dev)
226 {
227 	struct panel_module *panel_mod = to_panel_module(mod);
228 	struct tilcdc_drm_private *priv = dev->dev_private;
229 	struct drm_encoder *encoder;
230 	struct drm_connector *connector;
231 
232 	encoder = panel_encoder_create(dev, panel_mod);
233 	if (!encoder)
234 		return -ENOMEM;
235 
236 	connector = panel_connector_create(dev, panel_mod, encoder);
237 	if (!connector)
238 		return -ENOMEM;
239 
240 	priv->encoders[priv->num_encoders++] = encoder;
241 	priv->connectors[priv->num_connectors++] = connector;
242 
243 	tilcdc_crtc_set_panel_info(priv->crtc,
244 				   to_panel_encoder(encoder)->mod->info);
245 
246 	return 0;
247 }
248 
249 static const struct tilcdc_module_ops panel_module_ops = {
250 		.modeset_init = panel_modeset_init,
251 };
252 
253 /*
254  * Device:
255  */
256 
257 /* maybe move this somewhere common if it is needed by other outputs? */
258 static struct tilcdc_panel_info *of_get_panel_info(struct device_node *np)
259 {
260 	struct device_node *info_np;
261 	struct tilcdc_panel_info *info;
262 	int ret = 0;
263 
264 	if (!np) {
265 		pr_err("%s: no devicenode given\n", __func__);
266 		return NULL;
267 	}
268 
269 	info_np = of_get_child_by_name(np, "panel-info");
270 	if (!info_np) {
271 		pr_err("%s: could not find panel-info node\n", __func__);
272 		return NULL;
273 	}
274 
275 	info = kzalloc(sizeof(*info), GFP_KERNEL);
276 	if (!info)
277 		goto put_node;
278 
279 	ret |= of_property_read_u32(info_np, "ac-bias", &info->ac_bias);
280 	ret |= of_property_read_u32(info_np, "ac-bias-intrpt", &info->ac_bias_intrpt);
281 	ret |= of_property_read_u32(info_np, "dma-burst-sz", &info->dma_burst_sz);
282 	ret |= of_property_read_u32(info_np, "bpp", &info->bpp);
283 	ret |= of_property_read_u32(info_np, "fdd", &info->fdd);
284 	ret |= of_property_read_u32(info_np, "sync-edge", &info->sync_edge);
285 	ret |= of_property_read_u32(info_np, "sync-ctrl", &info->sync_ctrl);
286 	ret |= of_property_read_u32(info_np, "raster-order", &info->raster_order);
287 	ret |= of_property_read_u32(info_np, "fifo-th", &info->fifo_th);
288 
289 	/* optional: */
290 	info->tft_alt_mode      = of_property_read_bool(info_np, "tft-alt-mode");
291 	info->invert_pxl_clk    = of_property_read_bool(info_np, "invert-pxl-clk");
292 
293 	if (ret) {
294 		pr_err("%s: error reading panel-info properties\n", __func__);
295 		kfree(info);
296 		info = NULL;
297 	}
298 
299 put_node:
300 	of_node_put(info_np);
301 	return info;
302 }
303 
304 static int panel_probe(struct platform_device *pdev)
305 {
306 	struct device_node *bl_node, *node = pdev->dev.of_node;
307 	struct panel_module *panel_mod;
308 	struct tilcdc_module *mod;
309 	struct pinctrl *pinctrl;
310 	int ret;
311 
312 	/* bail out early if no DT data: */
313 	if (!node) {
314 		dev_err(&pdev->dev, "device-tree data is missing\n");
315 		return -ENXIO;
316 	}
317 
318 	panel_mod = devm_kzalloc(&pdev->dev, sizeof(*panel_mod), GFP_KERNEL);
319 	if (!panel_mod)
320 		return -ENOMEM;
321 
322 	bl_node = of_parse_phandle(node, "backlight", 0);
323 	if (bl_node) {
324 		panel_mod->backlight = of_find_backlight_by_node(bl_node);
325 		of_node_put(bl_node);
326 
327 		if (!panel_mod->backlight)
328 			return -EPROBE_DEFER;
329 
330 		dev_info(&pdev->dev, "found backlight\n");
331 	}
332 
333 	panel_mod->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
334 							 GPIOD_OUT_LOW);
335 	if (IS_ERR(panel_mod->enable_gpio)) {
336 		ret = PTR_ERR(panel_mod->enable_gpio);
337 		dev_err(&pdev->dev, "failed to request enable GPIO\n");
338 		goto fail_backlight;
339 	}
340 
341 	if (panel_mod->enable_gpio)
342 		dev_info(&pdev->dev, "found enable GPIO\n");
343 
344 	mod = &panel_mod->base;
345 	pdev->dev.platform_data = mod;
346 
347 	tilcdc_module_init(mod, "panel", &panel_module_ops);
348 
349 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
350 	if (IS_ERR(pinctrl))
351 		dev_warn(&pdev->dev, "pins are not configured\n");
352 
353 	panel_mod->timings = of_get_display_timings(node);
354 	if (!panel_mod->timings) {
355 		dev_err(&pdev->dev, "could not get panel timings\n");
356 		ret = -EINVAL;
357 		goto fail_free;
358 	}
359 
360 	panel_mod->info = of_get_panel_info(node);
361 	if (!panel_mod->info) {
362 		dev_err(&pdev->dev, "could not get panel info\n");
363 		ret = -EINVAL;
364 		goto fail_timings;
365 	}
366 
367 	return 0;
368 
369 fail_timings:
370 	display_timings_release(panel_mod->timings);
371 
372 fail_free:
373 	tilcdc_module_cleanup(mod);
374 
375 fail_backlight:
376 	if (panel_mod->backlight)
377 		put_device(&panel_mod->backlight->dev);
378 	return ret;
379 }
380 
381 static int panel_remove(struct platform_device *pdev)
382 {
383 	struct tilcdc_module *mod = dev_get_platdata(&pdev->dev);
384 	struct panel_module *panel_mod = to_panel_module(mod);
385 	struct backlight_device *backlight = panel_mod->backlight;
386 
387 	if (backlight)
388 		put_device(&backlight->dev);
389 
390 	display_timings_release(panel_mod->timings);
391 
392 	tilcdc_module_cleanup(mod);
393 	kfree(panel_mod->info);
394 
395 	return 0;
396 }
397 
398 static const struct of_device_id panel_of_match[] = {
399 		{ .compatible = "ti,tilcdc,panel", },
400 		{ },
401 };
402 
403 struct platform_driver panel_driver = {
404 	.probe = panel_probe,
405 	.remove = panel_remove,
406 	.driver = {
407 		.owner = THIS_MODULE,
408 		.name = "tilcdc-panel",
409 		.of_match_table = panel_of_match,
410 	},
411 };
412 
413 int __init tilcdc_panel_init(void)
414 {
415 	return platform_driver_register(&panel_driver);
416 }
417 
418 void __exit tilcdc_panel_fini(void)
419 {
420 	platform_driver_unregister(&panel_driver);
421 }
422