xref: /linux/drivers/gpu/drm/drm_modeset_helper.c (revision 504f9bdd3a1588604b0452bfe927ff86e5f6e6df)
1 /*
2  * Copyright (c) 2016 Intel Corporation
3  *
4  * Permission to use, copy, modify, distribute, and sell this software and its
5  * documentation for any purpose is hereby granted without fee, provided that
6  * the above copyright notice appear in all copies and that both that copyright
7  * notice and this permission notice appear in supporting documentation, and
8  * that the name of the copyright holders not be used in advertising or
9  * publicity pertaining to distribution of the software without specific,
10  * written prior permission.  The copyright holders make no representations
11  * about the suitability of this software for any purpose.  It is provided "as
12  * is" without express or implied warranty.
13  *
14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20  * OF THIS SOFTWARE.
21  */
22 
23 #include <linux/export.h>
24 
25 #include <drm/drm_atomic_helper.h>
26 #include <drm/drm_client_event.h>
27 #include <drm/drm_fourcc.h>
28 #include <drm/drm_framebuffer.h>
29 #include <drm/drm_modeset_helper.h>
30 #include <drm/drm_plane_helper.h>
31 #include <drm/drm_print.h>
32 #include <drm/drm_probe_helper.h>
33 
34 /**
35  * DOC: aux kms helpers
36  *
37  * This helper library contains various one-off functions which don't really fit
38  * anywhere else in the DRM modeset helper library.
39  */
40 
41 /**
42  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
43  * 						connector list
44  * @dev: drm device to operate on
45  *
46  * Some userspace presumes that the first connected connector is the main
47  * display, where it's supposed to display e.g. the login screen. For
48  * laptops, this should be the main panel. Use this function to sort all
49  * (eDP/LVDS/DSI) panels to the front of the connector list, instead of
50  * painstakingly trying to initialize them in the right order.
51  */
52 void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
53 {
54 	struct drm_connector *connector, *tmp;
55 	struct list_head panel_list;
56 
57 	INIT_LIST_HEAD(&panel_list);
58 
59 	spin_lock_irq(&dev->mode_config.connector_list_lock);
60 	list_for_each_entry_safe(connector, tmp,
61 				 &dev->mode_config.connector_list, head) {
62 		if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
63 		    connector->connector_type == DRM_MODE_CONNECTOR_eDP ||
64 		    connector->connector_type == DRM_MODE_CONNECTOR_DSI)
65 			list_move_tail(&connector->head, &panel_list);
66 	}
67 
68 	list_splice(&panel_list, &dev->mode_config.connector_list);
69 	spin_unlock_irq(&dev->mode_config.connector_list_lock);
70 }
71 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
72 
73 /**
74  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
75  * @dev: DRM device
76  * @fb: drm_framebuffer object to fill out
77  * @mode_cmd: metadata from the userspace fb creation request
78  *
79  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
80  * metadata fields.
81  */
82 void drm_helper_mode_fill_fb_struct(struct drm_device *dev,
83 				    struct drm_framebuffer *fb,
84 				    const struct drm_mode_fb_cmd2 *mode_cmd)
85 {
86 	int i;
87 
88 	fb->dev = dev;
89 	fb->format = drm_get_format_info(dev, mode_cmd);
90 	fb->width = mode_cmd->width;
91 	fb->height = mode_cmd->height;
92 	for (i = 0; i < 4; i++) {
93 		fb->pitches[i] = mode_cmd->pitches[i];
94 		fb->offsets[i] = mode_cmd->offsets[i];
95 	}
96 	fb->modifier = mode_cmd->modifier[0];
97 	fb->flags = mode_cmd->flags;
98 }
99 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
100 
101 /*
102  * This is the minimal list of formats that seem to be safe for modeset use
103  * with all current DRM drivers.  Most hardware can actually support more
104  * formats than this and drivers may specify a more accurate list when
105  * creating the primary plane.
106  */
107 static const uint32_t safe_modeset_formats[] = {
108 	DRM_FORMAT_XRGB8888,
109 	DRM_FORMAT_ARGB8888,
110 };
111 
112 static const struct drm_plane_funcs primary_plane_funcs = {
113 	DRM_PLANE_NON_ATOMIC_FUNCS,
114 };
115 
116 /**
117  * drm_crtc_init - Legacy CRTC initialization function
118  * @dev: DRM device
119  * @crtc: CRTC object to init
120  * @funcs: callbacks for the new CRTC
121  *
122  * Initialize a CRTC object with a default helper-provided primary plane and no
123  * cursor plane.
124  *
125  * Note that we make some assumptions about hardware limitations that may not be
126  * true for all hardware:
127  *
128  * 1. Primary plane cannot be repositioned.
129  * 2. Primary plane cannot be scaled.
130  * 3. Primary plane must cover the entire CRTC.
131  * 4. Subpixel positioning is not supported.
132  * 5. The primary plane must always be on if the CRTC is enabled.
133  *
134  * This is purely a backwards compatibility helper for old drivers. Drivers
135  * should instead implement their own primary plane. Atomic drivers must do so.
136  * Drivers with the above hardware restriction can look into using &struct
137  * drm_simple_display_pipe, which encapsulates the above limitations into a nice
138  * interface.
139  *
140  * Returns:
141  * Zero on success, error code on failure.
142  */
143 int drm_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
144 		  const struct drm_crtc_funcs *funcs)
145 {
146 	struct drm_plane *primary;
147 	int ret;
148 
149 	/* possible_crtc's will be filled in later by crtc_init */
150 	primary = __drm_universal_plane_alloc(dev, sizeof(*primary), 0, 0,
151 					      &primary_plane_funcs,
152 					      safe_modeset_formats,
153 					      ARRAY_SIZE(safe_modeset_formats),
154 					      NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
155 	if (IS_ERR(primary))
156 		return PTR_ERR(primary);
157 
158 	/*
159 	 * Remove the format_default field from drm_plane when dropping
160 	 * this helper.
161 	 */
162 	primary->format_default = true;
163 
164 	ret = drm_crtc_init_with_planes(dev, crtc, primary, NULL, funcs, NULL);
165 	if (ret)
166 		goto err_drm_plane_cleanup;
167 
168 	return 0;
169 
170 err_drm_plane_cleanup:
171 	drm_plane_cleanup(primary);
172 	kfree(primary);
173 	return ret;
174 }
175 EXPORT_SYMBOL(drm_crtc_init);
176 
177 /**
178  * drm_mode_config_helper_suspend - Modeset suspend helper
179  * @dev: DRM device
180  *
181  * This helper function takes care of suspending the modeset side. It disables
182  * output polling if initialized, suspends fbdev if used and finally calls
183  * drm_atomic_helper_suspend().
184  * If suspending fails, fbdev and polling is re-enabled.
185  *
186  * Returns:
187  * Zero on success, negative error code on error.
188  *
189  * See also:
190  * drm_kms_helper_poll_disable() and drm_client_dev_suspend().
191  */
192 int drm_mode_config_helper_suspend(struct drm_device *dev)
193 {
194 	struct drm_atomic_state *state;
195 
196 	if (!dev)
197 		return 0;
198 	/*
199 	 * Don't disable polling if it was never initialized
200 	 */
201 	if (dev->mode_config.poll_enabled)
202 		drm_kms_helper_poll_disable(dev);
203 
204 	drm_client_dev_suspend(dev, false);
205 	state = drm_atomic_helper_suspend(dev);
206 	if (IS_ERR(state)) {
207 		drm_client_dev_resume(dev, false);
208 
209 		/*
210 		 * Don't enable polling if it was never initialized
211 		 */
212 		if (dev->mode_config.poll_enabled)
213 			drm_kms_helper_poll_enable(dev);
214 
215 		return PTR_ERR(state);
216 	}
217 
218 	dev->mode_config.suspend_state = state;
219 
220 	return 0;
221 }
222 EXPORT_SYMBOL(drm_mode_config_helper_suspend);
223 
224 /**
225  * drm_mode_config_helper_resume - Modeset resume helper
226  * @dev: DRM device
227  *
228  * This helper function takes care of resuming the modeset side. It calls
229  * drm_atomic_helper_resume(), resumes fbdev if used and enables output polling
230  * if initiaized.
231  *
232  * Returns:
233  * Zero on success, negative error code on error.
234  *
235  * See also:
236  * drm_client_dev_resume() and drm_kms_helper_poll_enable().
237  */
238 int drm_mode_config_helper_resume(struct drm_device *dev)
239 {
240 	int ret;
241 
242 	if (!dev)
243 		return 0;
244 
245 	if (WARN_ON(!dev->mode_config.suspend_state))
246 		return -EINVAL;
247 
248 	ret = drm_atomic_helper_resume(dev, dev->mode_config.suspend_state);
249 	if (ret)
250 		DRM_ERROR("Failed to resume (%d)\n", ret);
251 	dev->mode_config.suspend_state = NULL;
252 
253 	drm_client_dev_resume(dev, false);
254 
255 	/*
256 	 * Don't enable polling if it is not initialized
257 	 */
258 	if (dev->mode_config.poll_enabled)
259 		drm_kms_helper_poll_enable(dev);
260 
261 	return ret;
262 }
263 EXPORT_SYMBOL(drm_mode_config_helper_resume);
264