xref: /linux/drivers/gpu/drm/tilcdc/tilcdc_panel.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
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 #include <linux/pinctrl/pinmux.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/backlight.h>
21 #include <linux/gpio/consumer.h>
22 #include <video/display_timing.h>
23 #include <video/of_display_timing.h>
24 #include <video/videomode.h>
25 #include <drm/drm_atomic_helper.h>
26 
27 #include "tilcdc_drv.h"
28 #include "tilcdc_panel.h"
29 
30 struct panel_module {
31 	struct tilcdc_module base;
32 	struct tilcdc_panel_info *info;
33 	struct display_timings *timings;
34 	struct backlight_device *backlight;
35 	struct gpio_desc *enable_gpio;
36 };
37 #define to_panel_module(x) container_of(x, struct panel_module, base)
38 
39 
40 /*
41  * Encoder:
42  */
43 
44 struct panel_encoder {
45 	struct drm_encoder base;
46 	struct panel_module *mod;
47 };
48 #define to_panel_encoder(x) container_of(x, struct panel_encoder, base)
49 
50 static void panel_encoder_dpms(struct drm_encoder *encoder, int mode)
51 {
52 	struct panel_encoder *panel_encoder = to_panel_encoder(encoder);
53 	struct backlight_device *backlight = panel_encoder->mod->backlight;
54 	struct gpio_desc *gpio = panel_encoder->mod->enable_gpio;
55 
56 	if (backlight) {
57 		backlight->props.power = mode == DRM_MODE_DPMS_ON ?
58 					 FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
59 		backlight_update_status(backlight);
60 	}
61 
62 	if (gpio)
63 		gpiod_set_value_cansleep(gpio,
64 					 mode == DRM_MODE_DPMS_ON ? 1 : 0);
65 }
66 
67 static void panel_encoder_prepare(struct drm_encoder *encoder)
68 {
69 	panel_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
70 }
71 
72 static void panel_encoder_commit(struct drm_encoder *encoder)
73 {
74 	panel_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
75 }
76 
77 static void panel_encoder_mode_set(struct drm_encoder *encoder,
78 		struct drm_display_mode *mode,
79 		struct drm_display_mode *adjusted_mode)
80 {
81 	/* nothing needed */
82 }
83 
84 static const struct drm_encoder_funcs panel_encoder_funcs = {
85 		.destroy        = drm_encoder_cleanup,
86 };
87 
88 static const struct drm_encoder_helper_funcs panel_encoder_helper_funcs = {
89 		.dpms           = panel_encoder_dpms,
90 		.prepare        = panel_encoder_prepare,
91 		.commit         = panel_encoder_commit,
92 		.mode_set       = panel_encoder_mode_set,
93 };
94 
95 static struct drm_encoder *panel_encoder_create(struct drm_device *dev,
96 		struct panel_module *mod)
97 {
98 	struct panel_encoder *panel_encoder;
99 	struct drm_encoder *encoder;
100 	int ret;
101 
102 	panel_encoder = devm_kzalloc(dev->dev, sizeof(*panel_encoder),
103 				     GFP_KERNEL);
104 	if (!panel_encoder)
105 		return NULL;
106 
107 	panel_encoder->mod = mod;
108 
109 	encoder = &panel_encoder->base;
110 	encoder->possible_crtcs = 1;
111 
112 	ret = drm_encoder_init(dev, encoder, &panel_encoder_funcs,
113 			DRM_MODE_ENCODER_LVDS, NULL);
114 	if (ret < 0)
115 		goto fail;
116 
117 	drm_encoder_helper_add(encoder, &panel_encoder_helper_funcs);
118 
119 	return encoder;
120 
121 fail:
122 	drm_encoder_cleanup(encoder);
123 	return NULL;
124 }
125 
126 /*
127  * Connector:
128  */
129 
130 struct panel_connector {
131 	struct drm_connector base;
132 
133 	struct drm_encoder *encoder;  /* our connected encoder */
134 	struct panel_module *mod;
135 };
136 #define to_panel_connector(x) container_of(x, struct panel_connector, base)
137 
138 
139 static void panel_connector_destroy(struct drm_connector *connector)
140 {
141 	drm_connector_unregister(connector);
142 	drm_connector_cleanup(connector);
143 }
144 
145 static int panel_connector_get_modes(struct drm_connector *connector)
146 {
147 	struct drm_device *dev = connector->dev;
148 	struct panel_connector *panel_connector = to_panel_connector(connector);
149 	struct display_timings *timings = panel_connector->mod->timings;
150 	int i;
151 
152 	for (i = 0; i < timings->num_timings; i++) {
153 		struct drm_display_mode *mode = drm_mode_create(dev);
154 		struct videomode vm;
155 
156 		if (videomode_from_timings(timings, &vm, i))
157 			break;
158 
159 		drm_display_mode_from_videomode(&vm, mode);
160 
161 		mode->type = DRM_MODE_TYPE_DRIVER;
162 
163 		if (timings->native_mode == i)
164 			mode->type |= DRM_MODE_TYPE_PREFERRED;
165 
166 		drm_mode_set_name(mode);
167 		drm_mode_probed_add(connector, mode);
168 	}
169 
170 	return i;
171 }
172 
173 static int panel_connector_mode_valid(struct drm_connector *connector,
174 		  struct drm_display_mode *mode)
175 {
176 	struct tilcdc_drm_private *priv = connector->dev->dev_private;
177 	/* our only constraints are what the crtc can generate: */
178 	return tilcdc_crtc_mode_valid(priv->crtc, mode);
179 }
180 
181 static struct drm_encoder *panel_connector_best_encoder(
182 		struct drm_connector *connector)
183 {
184 	struct panel_connector *panel_connector = to_panel_connector(connector);
185 	return panel_connector->encoder;
186 }
187 
188 static const struct drm_connector_funcs panel_connector_funcs = {
189 	.destroy            = panel_connector_destroy,
190 	.fill_modes         = drm_helper_probe_single_connector_modes,
191 	.reset              = drm_atomic_helper_connector_reset,
192 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
193 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
194 };
195 
196 static const struct drm_connector_helper_funcs panel_connector_helper_funcs = {
197 	.get_modes          = panel_connector_get_modes,
198 	.mode_valid         = panel_connector_mode_valid,
199 	.best_encoder       = panel_connector_best_encoder,
200 };
201 
202 static struct drm_connector *panel_connector_create(struct drm_device *dev,
203 		struct panel_module *mod, struct drm_encoder *encoder)
204 {
205 	struct panel_connector *panel_connector;
206 	struct drm_connector *connector;
207 	int ret;
208 
209 	panel_connector = devm_kzalloc(dev->dev, sizeof(*panel_connector),
210 				       GFP_KERNEL);
211 	if (!panel_connector)
212 		return NULL;
213 
214 	panel_connector->encoder = encoder;
215 	panel_connector->mod = mod;
216 
217 	connector = &panel_connector->base;
218 
219 	drm_connector_init(dev, connector, &panel_connector_funcs,
220 			DRM_MODE_CONNECTOR_LVDS);
221 	drm_connector_helper_add(connector, &panel_connector_helper_funcs);
222 
223 	connector->interlace_allowed = 0;
224 	connector->doublescan_allowed = 0;
225 
226 	ret = drm_connector_attach_encoder(connector, encoder);
227 	if (ret)
228 		goto fail;
229 
230 	return connector;
231 
232 fail:
233 	panel_connector_destroy(connector);
234 	return NULL;
235 }
236 
237 /*
238  * Module:
239  */
240 
241 static int panel_modeset_init(struct tilcdc_module *mod, struct drm_device *dev)
242 {
243 	struct panel_module *panel_mod = to_panel_module(mod);
244 	struct tilcdc_drm_private *priv = dev->dev_private;
245 	struct drm_encoder *encoder;
246 	struct drm_connector *connector;
247 
248 	encoder = panel_encoder_create(dev, panel_mod);
249 	if (!encoder)
250 		return -ENOMEM;
251 
252 	connector = panel_connector_create(dev, panel_mod, encoder);
253 	if (!connector)
254 		return -ENOMEM;
255 
256 	priv->encoders[priv->num_encoders++] = encoder;
257 	priv->connectors[priv->num_connectors++] = connector;
258 
259 	tilcdc_crtc_set_panel_info(priv->crtc,
260 				   to_panel_encoder(encoder)->mod->info);
261 
262 	return 0;
263 }
264 
265 static const struct tilcdc_module_ops panel_module_ops = {
266 		.modeset_init = panel_modeset_init,
267 };
268 
269 /*
270  * Device:
271  */
272 
273 /* maybe move this somewhere common if it is needed by other outputs? */
274 static struct tilcdc_panel_info *of_get_panel_info(struct device_node *np)
275 {
276 	struct device_node *info_np;
277 	struct tilcdc_panel_info *info;
278 	int ret = 0;
279 
280 	if (!np) {
281 		pr_err("%s: no devicenode given\n", __func__);
282 		return NULL;
283 	}
284 
285 	info_np = of_get_child_by_name(np, "panel-info");
286 	if (!info_np) {
287 		pr_err("%s: could not find panel-info node\n", __func__);
288 		return NULL;
289 	}
290 
291 	info = kzalloc(sizeof(*info), GFP_KERNEL);
292 	if (!info)
293 		goto put_node;
294 
295 	ret |= of_property_read_u32(info_np, "ac-bias", &info->ac_bias);
296 	ret |= of_property_read_u32(info_np, "ac-bias-intrpt", &info->ac_bias_intrpt);
297 	ret |= of_property_read_u32(info_np, "dma-burst-sz", &info->dma_burst_sz);
298 	ret |= of_property_read_u32(info_np, "bpp", &info->bpp);
299 	ret |= of_property_read_u32(info_np, "fdd", &info->fdd);
300 	ret |= of_property_read_u32(info_np, "sync-edge", &info->sync_edge);
301 	ret |= of_property_read_u32(info_np, "sync-ctrl", &info->sync_ctrl);
302 	ret |= of_property_read_u32(info_np, "raster-order", &info->raster_order);
303 	ret |= of_property_read_u32(info_np, "fifo-th", &info->fifo_th);
304 
305 	/* optional: */
306 	info->tft_alt_mode      = of_property_read_bool(info_np, "tft-alt-mode");
307 	info->invert_pxl_clk    = of_property_read_bool(info_np, "invert-pxl-clk");
308 
309 	if (ret) {
310 		pr_err("%s: error reading panel-info properties\n", __func__);
311 		kfree(info);
312 		info = NULL;
313 	}
314 
315 put_node:
316 	of_node_put(info_np);
317 	return info;
318 }
319 
320 static int panel_probe(struct platform_device *pdev)
321 {
322 	struct device_node *bl_node, *node = pdev->dev.of_node;
323 	struct panel_module *panel_mod;
324 	struct tilcdc_module *mod;
325 	struct pinctrl *pinctrl;
326 	int ret;
327 
328 	/* bail out early if no DT data: */
329 	if (!node) {
330 		dev_err(&pdev->dev, "device-tree data is missing\n");
331 		return -ENXIO;
332 	}
333 
334 	panel_mod = devm_kzalloc(&pdev->dev, sizeof(*panel_mod), GFP_KERNEL);
335 	if (!panel_mod)
336 		return -ENOMEM;
337 
338 	bl_node = of_parse_phandle(node, "backlight", 0);
339 	if (bl_node) {
340 		panel_mod->backlight = of_find_backlight_by_node(bl_node);
341 		of_node_put(bl_node);
342 
343 		if (!panel_mod->backlight)
344 			return -EPROBE_DEFER;
345 
346 		dev_info(&pdev->dev, "found backlight\n");
347 	}
348 
349 	panel_mod->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
350 							 GPIOD_OUT_LOW);
351 	if (IS_ERR(panel_mod->enable_gpio)) {
352 		ret = PTR_ERR(panel_mod->enable_gpio);
353 		dev_err(&pdev->dev, "failed to request enable GPIO\n");
354 		goto fail_backlight;
355 	}
356 
357 	if (panel_mod->enable_gpio)
358 		dev_info(&pdev->dev, "found enable GPIO\n");
359 
360 	mod = &panel_mod->base;
361 	pdev->dev.platform_data = mod;
362 
363 	tilcdc_module_init(mod, "panel", &panel_module_ops);
364 
365 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
366 	if (IS_ERR(pinctrl))
367 		dev_warn(&pdev->dev, "pins are not configured\n");
368 
369 	panel_mod->timings = of_get_display_timings(node);
370 	if (!panel_mod->timings) {
371 		dev_err(&pdev->dev, "could not get panel timings\n");
372 		ret = -EINVAL;
373 		goto fail_free;
374 	}
375 
376 	panel_mod->info = of_get_panel_info(node);
377 	if (!panel_mod->info) {
378 		dev_err(&pdev->dev, "could not get panel info\n");
379 		ret = -EINVAL;
380 		goto fail_timings;
381 	}
382 
383 	return 0;
384 
385 fail_timings:
386 	display_timings_release(panel_mod->timings);
387 
388 fail_free:
389 	tilcdc_module_cleanup(mod);
390 
391 fail_backlight:
392 	if (panel_mod->backlight)
393 		put_device(&panel_mod->backlight->dev);
394 	return ret;
395 }
396 
397 static int panel_remove(struct platform_device *pdev)
398 {
399 	struct tilcdc_module *mod = dev_get_platdata(&pdev->dev);
400 	struct panel_module *panel_mod = to_panel_module(mod);
401 	struct backlight_device *backlight = panel_mod->backlight;
402 
403 	if (backlight)
404 		put_device(&backlight->dev);
405 
406 	display_timings_release(panel_mod->timings);
407 
408 	tilcdc_module_cleanup(mod);
409 	kfree(panel_mod->info);
410 
411 	return 0;
412 }
413 
414 static const struct of_device_id panel_of_match[] = {
415 		{ .compatible = "ti,tilcdc,panel", },
416 		{ },
417 };
418 
419 struct platform_driver panel_driver = {
420 	.probe = panel_probe,
421 	.remove = panel_remove,
422 	.driver = {
423 		.owner = THIS_MODULE,
424 		.name = "tilcdc-panel",
425 		.of_match_table = panel_of_match,
426 	},
427 };
428 
429 int __init tilcdc_panel_init(void)
430 {
431 	return platform_driver_register(&panel_driver);
432 }
433 
434 void __exit tilcdc_panel_fini(void)
435 {
436 	platform_driver_unregister(&panel_driver);
437 }
438