xref: /openbmc/linux/drivers/gpu/drm/omapdrm/dss/base.c (revision 2645d8d0)
1 /*
2  * OMAP Display Subsystem Base
3  *
4  * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License for more details.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/list.h>
18 #include <linux/module.h>
19 #include <linux/mutex.h>
20 #include <linux/of.h>
21 #include <linux/of_graph.h>
22 
23 #include "dss.h"
24 #include "omapdss.h"
25 
26 static struct dss_device *dss_device;
27 
28 struct dss_device *omapdss_get_dss(void)
29 {
30 	return dss_device;
31 }
32 EXPORT_SYMBOL(omapdss_get_dss);
33 
34 void omapdss_set_dss(struct dss_device *dss)
35 {
36 	dss_device = dss;
37 }
38 EXPORT_SYMBOL(omapdss_set_dss);
39 
40 struct dispc_device *dispc_get_dispc(struct dss_device *dss)
41 {
42 	return dss->dispc;
43 }
44 EXPORT_SYMBOL(dispc_get_dispc);
45 
46 const struct dispc_ops *dispc_get_ops(struct dss_device *dss)
47 {
48 	return dss->dispc_ops;
49 }
50 EXPORT_SYMBOL(dispc_get_ops);
51 
52 
53 /* -----------------------------------------------------------------------------
54  * OMAP DSS Devices Handling
55  */
56 
57 static LIST_HEAD(omapdss_devices_list);
58 static DEFINE_MUTEX(omapdss_devices_lock);
59 
60 void omapdss_device_register(struct omap_dss_device *dssdev)
61 {
62 	mutex_lock(&omapdss_devices_lock);
63 	list_add_tail(&dssdev->list, &omapdss_devices_list);
64 	mutex_unlock(&omapdss_devices_lock);
65 }
66 EXPORT_SYMBOL_GPL(omapdss_device_register);
67 
68 void omapdss_device_unregister(struct omap_dss_device *dssdev)
69 {
70 	mutex_lock(&omapdss_devices_lock);
71 	list_del(&dssdev->list);
72 	mutex_unlock(&omapdss_devices_lock);
73 }
74 EXPORT_SYMBOL_GPL(omapdss_device_unregister);
75 
76 static bool omapdss_device_is_registered(struct device_node *node)
77 {
78 	struct omap_dss_device *dssdev;
79 	bool found = false;
80 
81 	mutex_lock(&omapdss_devices_lock);
82 
83 	list_for_each_entry(dssdev, &omapdss_devices_list, list) {
84 		if (dssdev->dev->of_node == node) {
85 			found = true;
86 			break;
87 		}
88 	}
89 
90 	mutex_unlock(&omapdss_devices_lock);
91 	return found;
92 }
93 
94 struct omap_dss_device *omapdss_device_get(struct omap_dss_device *dssdev)
95 {
96 	if (!try_module_get(dssdev->owner))
97 		return NULL;
98 
99 	if (get_device(dssdev->dev) == NULL) {
100 		module_put(dssdev->owner);
101 		return NULL;
102 	}
103 
104 	return dssdev;
105 }
106 EXPORT_SYMBOL(omapdss_device_get);
107 
108 void omapdss_device_put(struct omap_dss_device *dssdev)
109 {
110 	put_device(dssdev->dev);
111 	module_put(dssdev->owner);
112 }
113 EXPORT_SYMBOL(omapdss_device_put);
114 
115 struct omap_dss_device *omapdss_find_device_by_node(struct device_node *node)
116 {
117 	struct omap_dss_device *dssdev;
118 
119 	list_for_each_entry(dssdev, &omapdss_devices_list, list) {
120 		if (dssdev->dev->of_node == node)
121 			return omapdss_device_get(dssdev);
122 	}
123 
124 	return NULL;
125 }
126 
127 /*
128  * Search for the next output device starting at @from. Release the reference to
129  * the @from device, and acquire a reference to the returned device if found.
130  */
131 struct omap_dss_device *omapdss_device_next_output(struct omap_dss_device *from)
132 {
133 	struct omap_dss_device *dssdev;
134 	struct list_head *list;
135 
136 	mutex_lock(&omapdss_devices_lock);
137 
138 	if (list_empty(&omapdss_devices_list)) {
139 		dssdev = NULL;
140 		goto done;
141 	}
142 
143 	/*
144 	 * Start from the from entry if given or from omapdss_devices_list
145 	 * otherwise.
146 	 */
147 	list = from ? &from->list : &omapdss_devices_list;
148 
149 	list_for_each_entry(dssdev, list, list) {
150 		/*
151 		 * Stop if we reach the omapdss_devices_list, that's the end of
152 		 * the list.
153 		 */
154 		if (&dssdev->list == &omapdss_devices_list) {
155 			dssdev = NULL;
156 			goto done;
157 		}
158 
159 		if (dssdev->id && dssdev->next)
160 			goto done;
161 	}
162 
163 	dssdev = NULL;
164 
165 done:
166 	if (from)
167 		omapdss_device_put(from);
168 	if (dssdev)
169 		omapdss_device_get(dssdev);
170 
171 	mutex_unlock(&omapdss_devices_lock);
172 	return dssdev;
173 }
174 EXPORT_SYMBOL(omapdss_device_next_output);
175 
176 static bool omapdss_device_is_connected(struct omap_dss_device *dssdev)
177 {
178 	return dssdev->dss;
179 }
180 
181 int omapdss_device_connect(struct dss_device *dss,
182 			   struct omap_dss_device *src,
183 			   struct omap_dss_device *dst)
184 {
185 	int ret;
186 
187 	dev_dbg(dst->dev, "connect\n");
188 
189 	if (omapdss_device_is_connected(dst))
190 		return -EBUSY;
191 
192 	dst->dss = dss;
193 
194 	ret = dst->ops->connect(src, dst);
195 	if (ret < 0) {
196 		dst->dss = NULL;
197 		return ret;
198 	}
199 
200 	return 0;
201 }
202 EXPORT_SYMBOL_GPL(omapdss_device_connect);
203 
204 void omapdss_device_disconnect(struct omap_dss_device *src,
205 			       struct omap_dss_device *dst)
206 {
207 	dev_dbg(dst->dev, "disconnect\n");
208 
209 	if (!dst->id && !omapdss_device_is_connected(dst)) {
210 		WARN_ON(!dst->display);
211 		return;
212 	}
213 
214 	WARN_ON(dst->state != OMAP_DSS_DISPLAY_DISABLED);
215 
216 	dst->ops->disconnect(src, dst);
217 	dst->dss = NULL;
218 }
219 EXPORT_SYMBOL_GPL(omapdss_device_disconnect);
220 
221 void omapdss_device_pre_enable(struct omap_dss_device *dssdev)
222 {
223 	if (!dssdev)
224 		return;
225 
226 	omapdss_device_pre_enable(dssdev->next);
227 
228 	if (dssdev->ops->pre_enable)
229 		dssdev->ops->pre_enable(dssdev);
230 }
231 EXPORT_SYMBOL_GPL(omapdss_device_pre_enable);
232 
233 void omapdss_device_enable(struct omap_dss_device *dssdev)
234 {
235 	if (!dssdev)
236 		return;
237 
238 	if (dssdev->ops->enable)
239 		dssdev->ops->enable(dssdev);
240 
241 	omapdss_device_enable(dssdev->next);
242 
243 	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
244 }
245 EXPORT_SYMBOL_GPL(omapdss_device_enable);
246 
247 void omapdss_device_disable(struct omap_dss_device *dssdev)
248 {
249 	if (!dssdev)
250 		return;
251 
252 	omapdss_device_disable(dssdev->next);
253 
254 	if (dssdev->ops->disable)
255 		dssdev->ops->disable(dssdev);
256 }
257 EXPORT_SYMBOL_GPL(omapdss_device_disable);
258 
259 void omapdss_device_post_disable(struct omap_dss_device *dssdev)
260 {
261 	if (!dssdev)
262 		return;
263 
264 	if (dssdev->ops->post_disable)
265 		dssdev->ops->post_disable(dssdev);
266 
267 	omapdss_device_post_disable(dssdev->next);
268 
269 	dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
270 }
271 EXPORT_SYMBOL_GPL(omapdss_device_post_disable);
272 
273 /* -----------------------------------------------------------------------------
274  * Components Handling
275  */
276 
277 static struct list_head omapdss_comp_list;
278 
279 struct omapdss_comp_node {
280 	struct list_head list;
281 	struct device_node *node;
282 	bool dss_core_component;
283 };
284 
285 static bool omapdss_list_contains(const struct device_node *node)
286 {
287 	struct omapdss_comp_node *comp;
288 
289 	list_for_each_entry(comp, &omapdss_comp_list, list) {
290 		if (comp->node == node)
291 			return true;
292 	}
293 
294 	return false;
295 }
296 
297 static void omapdss_walk_device(struct device *dev, struct device_node *node,
298 				bool dss_core)
299 {
300 	struct device_node *n;
301 	struct omapdss_comp_node *comp = devm_kzalloc(dev, sizeof(*comp),
302 						      GFP_KERNEL);
303 
304 	if (comp) {
305 		comp->node = node;
306 		comp->dss_core_component = dss_core;
307 		list_add(&comp->list, &omapdss_comp_list);
308 	}
309 
310 	/*
311 	 * of_graph_get_remote_port_parent() prints an error if there is no
312 	 * port/ports node. To avoid that, check first that there's the node.
313 	 */
314 	n = of_get_child_by_name(node, "ports");
315 	if (!n)
316 		n = of_get_child_by_name(node, "port");
317 	if (!n)
318 		return;
319 
320 	of_node_put(n);
321 
322 	n = NULL;
323 	while ((n = of_graph_get_next_endpoint(node, n)) != NULL) {
324 		struct device_node *pn = of_graph_get_remote_port_parent(n);
325 
326 		if (!pn)
327 			continue;
328 
329 		if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {
330 			of_node_put(pn);
331 			continue;
332 		}
333 
334 		omapdss_walk_device(dev, pn, false);
335 	}
336 }
337 
338 void omapdss_gather_components(struct device *dev)
339 {
340 	struct device_node *child;
341 
342 	INIT_LIST_HEAD(&omapdss_comp_list);
343 
344 	omapdss_walk_device(dev, dev->of_node, true);
345 
346 	for_each_available_child_of_node(dev->of_node, child) {
347 		if (!of_find_property(child, "compatible", NULL))
348 			continue;
349 
350 		omapdss_walk_device(dev, child, true);
351 	}
352 }
353 EXPORT_SYMBOL(omapdss_gather_components);
354 
355 static bool omapdss_component_is_loaded(struct omapdss_comp_node *comp)
356 {
357 	if (comp->dss_core_component)
358 		return true;
359 	if (omapdss_device_is_registered(comp->node))
360 		return true;
361 
362 	return false;
363 }
364 
365 bool omapdss_stack_is_ready(void)
366 {
367 	struct omapdss_comp_node *comp;
368 
369 	list_for_each_entry(comp, &omapdss_comp_list, list) {
370 		if (!omapdss_component_is_loaded(comp))
371 			return false;
372 	}
373 
374 	return true;
375 }
376 EXPORT_SYMBOL(omapdss_stack_is_ready);
377 
378 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
379 MODULE_DESCRIPTION("OMAP Display Subsystem Base");
380 MODULE_LICENSE("GPL v2");
381