1 /*
2  * Exynos DRM Parallel output support.
3  *
4  * Copyright (c) 2014 Samsung Electronics Co., Ltd
5  *
6  * Contacts: Andrzej Hajda <a.hajda@samsung.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11 */
12 
13 #include <drm/drmP.h>
14 #include <drm/drm_crtc_helper.h>
15 #include <drm/drm_panel.h>
16 #include <drm/drm_atomic_helper.h>
17 
18 #include <linux/regulator/consumer.h>
19 
20 #include <video/of_videomode.h>
21 #include <video/videomode.h>
22 
23 #include "exynos_drm_crtc.h"
24 
25 struct exynos_dpi {
26 	struct drm_encoder encoder;
27 	struct device *dev;
28 	struct device_node *panel_node;
29 
30 	struct drm_panel *panel;
31 	struct drm_connector connector;
32 
33 	struct videomode *vm;
34 };
35 
36 #define connector_to_dpi(c) container_of(c, struct exynos_dpi, connector)
37 
38 static inline struct exynos_dpi *encoder_to_dpi(struct drm_encoder *e)
39 {
40 	return container_of(e, struct exynos_dpi, encoder);
41 }
42 
43 static enum drm_connector_status
44 exynos_dpi_detect(struct drm_connector *connector, bool force)
45 {
46 	struct exynos_dpi *ctx = connector_to_dpi(connector);
47 
48 	if (ctx->panel && !ctx->panel->connector)
49 		drm_panel_attach(ctx->panel, &ctx->connector);
50 
51 	return connector_status_connected;
52 }
53 
54 static void exynos_dpi_connector_destroy(struct drm_connector *connector)
55 {
56 	drm_connector_unregister(connector);
57 	drm_connector_cleanup(connector);
58 }
59 
60 static struct drm_connector_funcs exynos_dpi_connector_funcs = {
61 	.dpms = drm_atomic_helper_connector_dpms,
62 	.detect = exynos_dpi_detect,
63 	.fill_modes = drm_helper_probe_single_connector_modes,
64 	.destroy = exynos_dpi_connector_destroy,
65 	.reset = drm_atomic_helper_connector_reset,
66 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
67 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
68 };
69 
70 static int exynos_dpi_get_modes(struct drm_connector *connector)
71 {
72 	struct exynos_dpi *ctx = connector_to_dpi(connector);
73 
74 	/* fimd timings gets precedence over panel modes */
75 	if (ctx->vm) {
76 		struct drm_display_mode *mode;
77 
78 		mode = drm_mode_create(connector->dev);
79 		if (!mode) {
80 			DRM_ERROR("failed to create a new display mode\n");
81 			return 0;
82 		}
83 		drm_display_mode_from_videomode(ctx->vm, mode);
84 		mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
85 		drm_mode_probed_add(connector, mode);
86 		return 1;
87 	}
88 
89 	if (ctx->panel)
90 		return ctx->panel->funcs->get_modes(ctx->panel);
91 
92 	return 0;
93 }
94 
95 static struct drm_encoder *
96 exynos_dpi_best_encoder(struct drm_connector *connector)
97 {
98 	struct exynos_dpi *ctx = connector_to_dpi(connector);
99 
100 	return &ctx->encoder;
101 }
102 
103 static struct drm_connector_helper_funcs exynos_dpi_connector_helper_funcs = {
104 	.get_modes = exynos_dpi_get_modes,
105 	.best_encoder = exynos_dpi_best_encoder,
106 };
107 
108 static int exynos_dpi_create_connector(struct drm_encoder *encoder)
109 {
110 	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
111 	struct drm_connector *connector = &ctx->connector;
112 	int ret;
113 
114 	connector->polled = DRM_CONNECTOR_POLL_HPD;
115 
116 	ret = drm_connector_init(encoder->dev, connector,
117 				 &exynos_dpi_connector_funcs,
118 				 DRM_MODE_CONNECTOR_VGA);
119 	if (ret) {
120 		DRM_ERROR("failed to initialize connector with drm\n");
121 		return ret;
122 	}
123 
124 	drm_connector_helper_add(connector, &exynos_dpi_connector_helper_funcs);
125 	drm_connector_register(connector);
126 	drm_mode_connector_attach_encoder(connector, encoder);
127 
128 	return 0;
129 }
130 
131 static bool exynos_dpi_mode_fixup(struct drm_encoder *encoder,
132 				  const struct drm_display_mode *mode,
133 				  struct drm_display_mode *adjusted_mode)
134 {
135 	return true;
136 }
137 
138 static void exynos_dpi_mode_set(struct drm_encoder *encoder,
139 				struct drm_display_mode *mode,
140 				struct drm_display_mode *adjusted_mode)
141 {
142 }
143 
144 static void exynos_dpi_enable(struct drm_encoder *encoder)
145 {
146 	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
147 
148 	if (ctx->panel) {
149 		drm_panel_prepare(ctx->panel);
150 		drm_panel_enable(ctx->panel);
151 	}
152 }
153 
154 static void exynos_dpi_disable(struct drm_encoder *encoder)
155 {
156 	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
157 
158 	if (ctx->panel) {
159 		drm_panel_disable(ctx->panel);
160 		drm_panel_unprepare(ctx->panel);
161 	}
162 }
163 
164 static struct drm_encoder_helper_funcs exynos_dpi_encoder_helper_funcs = {
165 	.mode_fixup = exynos_dpi_mode_fixup,
166 	.mode_set = exynos_dpi_mode_set,
167 	.enable = exynos_dpi_enable,
168 	.disable = exynos_dpi_disable,
169 };
170 
171 static struct drm_encoder_funcs exynos_dpi_encoder_funcs = {
172 	.destroy = drm_encoder_cleanup,
173 };
174 
175 /* of_* functions will be removed after merge of of_graph patches */
176 static struct device_node *
177 of_get_child_by_name_reg(struct device_node *parent, const char *name, u32 reg)
178 {
179 	struct device_node *np;
180 
181 	for_each_child_of_node(parent, np) {
182 		u32 r;
183 
184 		if (!np->name || of_node_cmp(np->name, name))
185 			continue;
186 
187 		if (of_property_read_u32(np, "reg", &r) < 0)
188 			r = 0;
189 
190 		if (reg == r)
191 			break;
192 	}
193 
194 	return np;
195 }
196 
197 static struct device_node *of_graph_get_port_by_reg(struct device_node *parent,
198 						    u32 reg)
199 {
200 	struct device_node *ports, *port;
201 
202 	ports = of_get_child_by_name(parent, "ports");
203 	if (ports)
204 		parent = ports;
205 
206 	port = of_get_child_by_name_reg(parent, "port", reg);
207 
208 	of_node_put(ports);
209 
210 	return port;
211 }
212 
213 static struct device_node *
214 of_graph_get_endpoint_by_reg(struct device_node *port, u32 reg)
215 {
216 	return of_get_child_by_name_reg(port, "endpoint", reg);
217 }
218 
219 static struct device_node *
220 of_graph_get_remote_port_parent(const struct device_node *node)
221 {
222 	struct device_node *np;
223 	unsigned int depth;
224 
225 	np = of_parse_phandle(node, "remote-endpoint", 0);
226 
227 	/* Walk 3 levels up only if there is 'ports' node. */
228 	for (depth = 3; depth && np; depth--) {
229 		np = of_get_next_parent(np);
230 		if (depth == 2 && of_node_cmp(np->name, "ports"))
231 			break;
232 	}
233 	return np;
234 }
235 
236 enum {
237 	FIMD_PORT_IN0,
238 	FIMD_PORT_IN1,
239 	FIMD_PORT_IN2,
240 	FIMD_PORT_RGB,
241 	FIMD_PORT_WRB,
242 };
243 
244 static struct device_node *exynos_dpi_of_find_panel_node(struct device *dev)
245 {
246 	struct device_node *np, *ep;
247 
248 	np = of_graph_get_port_by_reg(dev->of_node, FIMD_PORT_RGB);
249 	if (!np)
250 		return NULL;
251 
252 	ep = of_graph_get_endpoint_by_reg(np, 0);
253 	of_node_put(np);
254 	if (!ep)
255 		return NULL;
256 
257 	np = of_graph_get_remote_port_parent(ep);
258 	of_node_put(ep);
259 
260 	return np;
261 }
262 
263 static int exynos_dpi_parse_dt(struct exynos_dpi *ctx)
264 {
265 	struct device *dev = ctx->dev;
266 	struct device_node *dn = dev->of_node;
267 	struct device_node *np;
268 
269 	ctx->panel_node = exynos_dpi_of_find_panel_node(dev);
270 
271 	np = of_get_child_by_name(dn, "display-timings");
272 	if (np) {
273 		struct videomode *vm;
274 		int ret;
275 
276 		of_node_put(np);
277 
278 		vm = devm_kzalloc(dev, sizeof(*ctx->vm), GFP_KERNEL);
279 		if (!vm)
280 			return -ENOMEM;
281 
282 		ret = of_get_videomode(dn, vm, 0);
283 		if (ret < 0) {
284 			devm_kfree(dev, vm);
285 			return ret;
286 		}
287 
288 		ctx->vm = vm;
289 
290 		return 0;
291 	}
292 
293 	if (!ctx->panel_node)
294 		return -EINVAL;
295 
296 	return 0;
297 }
298 
299 int exynos_dpi_bind(struct drm_device *dev, struct drm_encoder *encoder)
300 {
301 	int ret;
302 
303 	ret = exynos_drm_crtc_get_pipe_from_type(dev, EXYNOS_DISPLAY_TYPE_LCD);
304 	if (ret < 0)
305 		return ret;
306 
307 	encoder->possible_crtcs = 1 << ret;
308 
309 	DRM_DEBUG_KMS("possible_crtcs = 0x%x\n", encoder->possible_crtcs);
310 
311 	drm_encoder_init(dev, encoder, &exynos_dpi_encoder_funcs,
312 			 DRM_MODE_ENCODER_TMDS);
313 
314 	drm_encoder_helper_add(encoder, &exynos_dpi_encoder_helper_funcs);
315 
316 	ret = exynos_dpi_create_connector(encoder);
317 	if (ret) {
318 		DRM_ERROR("failed to create connector ret = %d\n", ret);
319 		drm_encoder_cleanup(encoder);
320 		return ret;
321 	}
322 
323 	return 0;
324 }
325 
326 struct drm_encoder *exynos_dpi_probe(struct device *dev)
327 {
328 	struct exynos_dpi *ctx;
329 	int ret;
330 
331 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
332 	if (!ctx)
333 		return ERR_PTR(-ENOMEM);
334 
335 	ctx->dev = dev;
336 
337 	ret = exynos_dpi_parse_dt(ctx);
338 	if (ret < 0) {
339 		devm_kfree(dev, ctx);
340 		return NULL;
341 	}
342 
343 	if (ctx->panel_node) {
344 		ctx->panel = of_drm_find_panel(ctx->panel_node);
345 		if (!ctx->panel)
346 			return ERR_PTR(-EPROBE_DEFER);
347 	}
348 
349 	return &ctx->encoder;
350 }
351 
352 int exynos_dpi_remove(struct drm_encoder *encoder)
353 {
354 	struct exynos_dpi *ctx = encoder_to_dpi(encoder);
355 
356 	exynos_dpi_disable(&ctx->encoder);
357 
358 	if (ctx->panel)
359 		drm_panel_detach(ctx->panel);
360 
361 	return 0;
362 }
363