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