xref: /linux/drivers/gpu/drm/bridge/panel.c (revision aaa44952bbd1d4db14a4d676bf9595bb5db7e7b0)
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 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
91 	struct drm_connector *connector = &panel_bridge->connector;
92 
93 	/*
94 	 * Cleanup the connector if we know it was initialized.
95 	 *
96 	 * FIXME: This wouldn't be needed if the panel_bridge structure was
97 	 * allocated with drmm_kzalloc(). This might be tricky since the
98 	 * drm_device pointer can only be retrieved when the bridge is attached.
99 	 */
100 	if (connector->dev)
101 		drm_connector_cleanup(connector);
102 }
103 
104 static void panel_bridge_pre_enable(struct drm_bridge *bridge)
105 {
106 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
107 
108 	drm_panel_prepare(panel_bridge->panel);
109 }
110 
111 static void panel_bridge_enable(struct drm_bridge *bridge)
112 {
113 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
114 
115 	drm_panel_enable(panel_bridge->panel);
116 }
117 
118 static void panel_bridge_disable(struct drm_bridge *bridge)
119 {
120 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
121 
122 	drm_panel_disable(panel_bridge->panel);
123 }
124 
125 static void panel_bridge_post_disable(struct drm_bridge *bridge)
126 {
127 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
128 
129 	drm_panel_unprepare(panel_bridge->panel);
130 }
131 
132 static int panel_bridge_get_modes(struct drm_bridge *bridge,
133 				  struct drm_connector *connector)
134 {
135 	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
136 
137 	return drm_panel_get_modes(panel_bridge->panel, connector);
138 }
139 
140 static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
141 	.attach = panel_bridge_attach,
142 	.detach = panel_bridge_detach,
143 	.pre_enable = panel_bridge_pre_enable,
144 	.enable = panel_bridge_enable,
145 	.disable = panel_bridge_disable,
146 	.post_disable = panel_bridge_post_disable,
147 	.get_modes = panel_bridge_get_modes,
148 	.atomic_reset = drm_atomic_helper_bridge_reset,
149 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
150 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
151 	.atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
152 };
153 
154 /**
155  * drm_panel_bridge_add - Creates a &drm_bridge and &drm_connector that
156  * just calls the appropriate functions from &drm_panel.
157  *
158  * @panel: The drm_panel being wrapped.  Must be non-NULL.
159  *
160  * For drivers converting from directly using drm_panel: The expected
161  * usage pattern is that during either encoder module probe or DSI
162  * host attach, a drm_panel will be looked up through
163  * drm_of_find_panel_or_bridge().  drm_panel_bridge_add() is used to
164  * wrap that panel in the new bridge, and the result can then be
165  * passed to drm_bridge_attach().  The drm_panel_prepare() and related
166  * functions can be dropped from the encoder driver (they're now
167  * called by the KMS helpers before calling into the encoder), along
168  * with connector creation.  When done with the bridge (after
169  * drm_mode_config_cleanup() if the bridge has already been attached), then
170  * drm_panel_bridge_remove() to free it.
171  *
172  * The connector type is set to @panel->connector_type, which must be set to a
173  * known type. Calling this function with a panel whose connector type is
174  * DRM_MODE_CONNECTOR_Unknown will return ERR_PTR(-EINVAL).
175  *
176  * See devm_drm_panel_bridge_add() for an automatically managed version of this
177  * function.
178  */
179 struct drm_bridge *drm_panel_bridge_add(struct drm_panel *panel)
180 {
181 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
182 		return ERR_PTR(-EINVAL);
183 
184 	return drm_panel_bridge_add_typed(panel, panel->connector_type);
185 }
186 EXPORT_SYMBOL(drm_panel_bridge_add);
187 
188 /**
189  * drm_panel_bridge_add_typed - Creates a &drm_bridge and &drm_connector with
190  * an explicit connector type.
191  * @panel: The drm_panel being wrapped.  Must be non-NULL.
192  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
193  *
194  * This is just like drm_panel_bridge_add(), but forces the connector type to
195  * @connector_type instead of infering it from the panel.
196  *
197  * This function is deprecated and should not be used in new drivers. Use
198  * drm_panel_bridge_add() instead, and fix panel drivers as necessary if they
199  * don't report a connector type.
200  */
201 struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
202 					      u32 connector_type)
203 {
204 	struct panel_bridge *panel_bridge;
205 
206 	if (!panel)
207 		return ERR_PTR(-EINVAL);
208 
209 	panel_bridge = devm_kzalloc(panel->dev, sizeof(*panel_bridge),
210 				    GFP_KERNEL);
211 	if (!panel_bridge)
212 		return ERR_PTR(-ENOMEM);
213 
214 	panel_bridge->connector_type = connector_type;
215 	panel_bridge->panel = panel;
216 
217 	panel_bridge->bridge.funcs = &panel_bridge_bridge_funcs;
218 #ifdef CONFIG_OF
219 	panel_bridge->bridge.of_node = panel->dev->of_node;
220 #endif
221 	panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
222 	panel_bridge->bridge.type = connector_type;
223 
224 	drm_bridge_add(&panel_bridge->bridge);
225 
226 	return &panel_bridge->bridge;
227 }
228 EXPORT_SYMBOL(drm_panel_bridge_add_typed);
229 
230 /**
231  * drm_panel_bridge_remove - Unregisters and frees a drm_bridge
232  * created by drm_panel_bridge_add().
233  *
234  * @bridge: The drm_bridge being freed.
235  */
236 void drm_panel_bridge_remove(struct drm_bridge *bridge)
237 {
238 	struct panel_bridge *panel_bridge;
239 
240 	if (!bridge)
241 		return;
242 
243 	if (bridge->funcs != &panel_bridge_bridge_funcs)
244 		return;
245 
246 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
247 
248 	drm_bridge_remove(bridge);
249 	devm_kfree(panel_bridge->panel->dev, bridge);
250 }
251 EXPORT_SYMBOL(drm_panel_bridge_remove);
252 
253 static void devm_drm_panel_bridge_release(struct device *dev, void *res)
254 {
255 	struct drm_bridge **bridge = res;
256 
257 	drm_panel_bridge_remove(*bridge);
258 }
259 
260 /**
261  * devm_drm_panel_bridge_add - Creates a managed &drm_bridge and &drm_connector
262  * that just calls the appropriate functions from &drm_panel.
263  * @dev: device to tie the bridge lifetime to
264  * @panel: The drm_panel being wrapped.  Must be non-NULL.
265  *
266  * This is the managed version of drm_panel_bridge_add() which automatically
267  * calls drm_panel_bridge_remove() when @dev is unbound.
268  */
269 struct drm_bridge *devm_drm_panel_bridge_add(struct device *dev,
270 					     struct drm_panel *panel)
271 {
272 	if (WARN_ON(panel->connector_type == DRM_MODE_CONNECTOR_Unknown))
273 		return ERR_PTR(-EINVAL);
274 
275 	return devm_drm_panel_bridge_add_typed(dev, panel,
276 					       panel->connector_type);
277 }
278 EXPORT_SYMBOL(devm_drm_panel_bridge_add);
279 
280 /**
281  * devm_drm_panel_bridge_add_typed - Creates a managed &drm_bridge and
282  * &drm_connector with an explicit connector type.
283  * @dev: device to tie the bridge lifetime to
284  * @panel: The drm_panel being wrapped.  Must be non-NULL.
285  * @connector_type: The connector type (DRM_MODE_CONNECTOR_*)
286  *
287  * This is just like devm_drm_panel_bridge_add(), but forces the connector type
288  * to @connector_type instead of infering it from the panel.
289  *
290  * This function is deprecated and should not be used in new drivers. Use
291  * devm_drm_panel_bridge_add() instead, and fix panel drivers as necessary if
292  * they don't report a connector type.
293  */
294 struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
295 						   struct drm_panel *panel,
296 						   u32 connector_type)
297 {
298 	struct drm_bridge **ptr, *bridge;
299 
300 	ptr = devres_alloc(devm_drm_panel_bridge_release, sizeof(*ptr),
301 			   GFP_KERNEL);
302 	if (!ptr)
303 		return ERR_PTR(-ENOMEM);
304 
305 	bridge = drm_panel_bridge_add_typed(panel, connector_type);
306 	if (!IS_ERR(bridge)) {
307 		*ptr = bridge;
308 		devres_add(dev, ptr);
309 	} else {
310 		devres_free(ptr);
311 	}
312 
313 	return bridge;
314 }
315 EXPORT_SYMBOL(devm_drm_panel_bridge_add_typed);
316 
317 /**
318  * drm_panel_bridge_connector - return the connector for the panel bridge
319  * @bridge: The drm_bridge.
320  *
321  * drm_panel_bridge creates the connector.
322  * This function gives external access to the connector.
323  *
324  * Returns: Pointer to drm_connector
325  */
326 struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge)
327 {
328 	struct panel_bridge *panel_bridge;
329 
330 	panel_bridge = drm_bridge_to_panel_bridge(bridge);
331 
332 	return &panel_bridge->connector;
333 }
334 EXPORT_SYMBOL(drm_panel_bridge_connector);
335