xref: /openbmc/linux/drivers/gpu/drm/bridge/panel.c (revision 8ffdff6a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
4  * Copyright (C) 2017 Broadcom
5  */
6 
7 #include <drm/drm_atomic_helper.h>
8 #include <drm/drm_bridge.h>
9 #include <drm/drm_connector.h>
10 #include <drm/drm_encoder.h>
11 #include <drm/drm_modeset_helper_vtables.h>
12 #include <drm/drm_panel.h>
13 #include <drm/drm_print.h>
14 #include <drm/drm_probe_helper.h>
15 
16 struct panel_bridge {
17 	struct drm_bridge bridge;
18 	struct drm_connector connector;
19 	struct drm_panel *panel;
20 	u32 connector_type;
21 };
22 
23 static inline struct panel_bridge *
24 drm_bridge_to_panel_bridge(struct drm_bridge *bridge)
25 {
26 	return container_of(bridge, struct panel_bridge, bridge);
27 }
28 
29 static inline struct panel_bridge *
30 drm_connector_to_panel_bridge(struct drm_connector *connector)
31 {
32 	return container_of(connector, struct panel_bridge, connector);
33 }
34 
35 static int panel_bridge_connector_get_modes(struct drm_connector *connector)
36 {
37 	struct panel_bridge *panel_bridge =
38 		drm_connector_to_panel_bridge(connector);
39 
40 	return drm_panel_get_modes(panel_bridge->panel, connector);
41 }
42 
43 static const struct drm_connector_helper_funcs
44 panel_bridge_connector_helper_funcs = {
45 	.get_modes = panel_bridge_connector_get_modes,
46 };
47 
48 static const struct drm_connector_funcs panel_bridge_connector_funcs = {
49 	.reset = drm_atomic_helper_connector_reset,
50 	.fill_modes = drm_helper_probe_single_connector_modes,
51 	.destroy = drm_connector_cleanup,
52 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
53 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
54 };
55 
56 static int panel_bridge_attach(struct drm_bridge *bridge,
57 			       enum drm_bridge_attach_flags flags)
58 {
59 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
60 	struct drm_connector *connector = &panel_bridge->connector;
61 	int ret;
62 
63 	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
64 		return 0;
65 
66 	if (!bridge->encoder) {
67 		DRM_ERROR("Missing encoder\n");
68 		return -ENODEV;
69 	}
70 
71 	drm_connector_helper_add(connector,
72 				 &panel_bridge_connector_helper_funcs);
73 
74 	ret = drm_connector_init(bridge->dev, connector,
75 				 &panel_bridge_connector_funcs,
76 				 panel_bridge->connector_type);
77 	if (ret) {
78 		DRM_ERROR("Failed to initialize connector\n");
79 		return ret;
80 	}
81 
82 	drm_connector_attach_encoder(&panel_bridge->connector,
83 					  bridge->encoder);
84 
85 	return 0;
86 }
87 
88 static void panel_bridge_detach(struct drm_bridge *bridge)
89 {
90 }
91 
92 static void panel_bridge_pre_enable(struct drm_bridge *bridge)
93 {
94 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
95 
96 	drm_panel_prepare(panel_bridge->panel);
97 }
98 
99 static void panel_bridge_enable(struct drm_bridge *bridge)
100 {
101 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
102 
103 	drm_panel_enable(panel_bridge->panel);
104 }
105 
106 static void panel_bridge_disable(struct drm_bridge *bridge)
107 {
108 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
109 
110 	drm_panel_disable(panel_bridge->panel);
111 }
112 
113 static void panel_bridge_post_disable(struct drm_bridge *bridge)
114 {
115 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
116 
117 	drm_panel_unprepare(panel_bridge->panel);
118 }
119 
120 static int panel_bridge_get_modes(struct drm_bridge *bridge,
121 				  struct drm_connector *connector)
122 {
123 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
124 
125 	return drm_panel_get_modes(panel_bridge->panel, connector);
126 }
127 
128 static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
129 	.attach = panel_bridge_attach,
130 	.detach = panel_bridge_detach,
131 	.pre_enable = panel_bridge_pre_enable,
132 	.enable = panel_bridge_enable,
133 	.disable = panel_bridge_disable,
134 	.post_disable = panel_bridge_post_disable,
135 	.get_modes = panel_bridge_get_modes,
136 	.atomic_reset = drm_atomic_helper_bridge_reset,
137 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
138 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
139 	.atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
140 };
141 
142 /**
143  * drm_panel_bridge_add - Creates a &drm_bridge and &drm_connector that
144  * just calls the appropriate functions from &drm_panel.
145  *
146  * @panel: The drm_panel being wrapped.  Must be non-NULL.
147  *
148  * For drivers converting from directly using drm_panel: The expected
149  * usage pattern is that during either encoder module probe or DSI
150  * host attach, a drm_panel will be looked up through
151  * drm_of_find_panel_or_bridge().  drm_panel_bridge_add() is used to
152  * wrap that panel in the new bridge, and the result can then be
153  * passed to drm_bridge_attach().  The drm_panel_prepare() and related
154  * functions can be dropped from the encoder driver (they're now
155  * called by the KMS helpers before calling into the encoder), along
156  * with connector creation.  When done with the bridge (after
157  * drm_mode_config_cleanup() if the bridge has already been attached), then
158  * drm_panel_bridge_remove() to free it.
159  *
160  * The connector type is set to @panel->connector_type, which must be set to a
161  * known type. Calling this function with a panel whose connector type is
162  * DRM_MODE_CONNECTOR_Unknown will return ERR_PTR(-EINVAL).
163  *
164  * See devm_drm_panel_bridge_add() for an automatically managed version of this
165  * function.
166  */
167 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel)
168 {
169 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
170 		return ERR_PTR(-EINVAL);
171 
172 	return drm_panel_bridge_add_typed(panel, panel->connector_type);
173 }
174 EXPORT_SYMBOL(drm_panel_bridge_add);
175 
176 /**
177  * drm_panel_bridge_add_typed - Creates a &drm_bridge and &drm_connector with
178  * an explicit connector type.
179  * @panel: The drm_panel being wrapped.  Must be non-NULL.
180  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
181  *
182  * This is just like drm_panel_bridge_add(), but forces the connector type to
183  * @connector_type instead of infering it from the panel.
184  *
185  * This function is deprecated and should not be used in new drivers. Use
186  * drm_panel_bridge_add() instead, and fix panel drivers as necessary if they
187  * don't report a connector type.
188  */
189 struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
190 					      u32 connector_type)
191 {
192 	struct panel_bridge *panel_bridge;
193 
194 	if (!panel)
195 		return ERR_PTR(-EINVAL);
196 
197 	panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge),
198 				    GFP_KERNEL);
199 	if (!panel_bridge)
200 		return ERR_PTR(-ENOMEM);
201 
202 	panel_bridge->connector_type = connector_type;
203 	panel_bridge->panel = panel;
204 
205 	panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs;
206 #ifdef CONFIG_OF
207 	panel_bridge->bridge.of_node = panel->dev->of_node;
208 #endif
209 	panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
210 	panel_bridge->bridge.type = connector_type;
211 
212 	drm_bridge_add(&panel_bridge->bridge);
213 
214 	return &panel_bridge->bridge;
215 }
216 EXPORT_SYMBOL(drm_panel_bridge_add_typed);
217 
218 /**
219  * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
220  * created by drm_panel_bridge_add().
221  *
222  * @bridge: The drm_bridge being freed.
223  */
224 void drm_panel_bridge_remove(struct drm_bridge *bridge)
225 {
226 	struct panel_bridge *panel_bridge;
227 
228 	if (!bridge)
229 		return;
230 
231 	if (bridge->funcs != &panel_bridge_bridge_funcs)
232 		return;
233 
234 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
235 
236 	drm_bridge_remove(bridge);
237 	devm_kfree(panel_bridge->panel->dev, bridge);
238 }
239 EXPORT_SYMBOL(drm_panel_bridge_remove);
240 
241 static void devm_drm_panel_bridge_release(struct device *dev, void *res)
242 {
243 	struct drm_bridge **bridge = res;
244 
245 	drm_panel_bridge_remove(*bridge);
246 }
247 
248 /**
249  * devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
250  * that just calls the appropriate functions from &drm_panel.
251  * @dev: device to tie the bridge lifetime to
252  * @panel: The drm_panel being wrapped.  Must be non-NULL.
253  *
254  * This is the managed version of drm_panel_bridge_add() which automatically
255  * calls drm_panel_bridge_remove() when @dev is unbound.
256  */
257 struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
258 					     struct drm_panel *panel)
259 {
260 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
261 		return ERR_PTR(-EINVAL);
262 
263 	return devm_drm_panel_bridge_add_typed(dev, panel,
264 					       panel->connector_type);
265 }
266 EXPORT_SYMBOL(devm_drm_panel_bridge_add);
267 
268 /**
269  * devm_drm_panel_bridge_add_typed - Creates a managed &drm_bridge and
270  * &drm_connector with an explicit connector type.
271  * @dev: device to tie the bridge lifetime to
272  * @panel: The drm_panel being wrapped.  Must be non-NULL.
273  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
274  *
275  * This is just like devm_drm_panel_bridge_add(), but forces the connector type
276  * to @connector_type instead of infering it from the panel.
277  *
278  * This function is deprecated and should not be used in new drivers. Use
279  * devm_drm_panel_bridge_add() instead, and fix panel drivers as necessary if
280  * they don't report a connector type.
281  */
282 struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
283 						   struct drm_panel *panel,
284 						   u32 connector_type)
285 {
286 	struct drm_bridge **ptr, *bridge;
287 
288 	ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
289 			   GFP_KERNEL);
290 	if (!ptr)
291 		return ERR_PTR(-ENOMEM);
292 
293 	bridge = drm_panel_bridge_add_typed(panel, connector_type);
294 	if (!IS_ERR(bridge)) {
295 		*ptr = bridge;
296 		devres_add(dev, ptr);
297 	} else {
298 		devres_free(ptr);
299 	}
300 
301 	return bridge;
302 }
303 EXPORT_SYMBOL(devm_drm_panel_bridge_add_typed);
304 
305 /**
306  * drm_panel_bridge_connector - return the connector for the panel bridge
307  * @bridge: The drm_bridge.
308  *
309  * drm_panel_bridge creates the connector.
310  * This function gives external access to the connector.
311  *
312  * Returns: Pointer to drm_connector
313  */
314 struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge)
315 {
316 	struct panel_bridge *panel_bridge;
317 
318 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
319 
320 	return &panel_bridge->connector;
321 }
322 EXPORT_SYMBOL(drm_panel_bridge_connector);
323