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