xref: /linux/drivers/gpu/drm/drm_modeset_helper.c (revision 40286d6379aacfcc053253ef78dc78b09addffda)
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  * @info: pixel format information
78  * @mode_cmd: metadata from the userspace fb creation request
79  *
80  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
81  * metadata fields.
82  */
83 void drm_helper_mode_fill_fb_struct(struct drm_device *dev,
84 				    struct drm_framebuffer *fb,
85 				    const struct drm_format_info *info,
86 				    const struct drm_mode_fb_cmd2 *mode_cmd)
87 {
88 	int i;
89 
90 	fb->dev = dev;
91 	fb->format = info;
92 	fb->width = mode_cmd->width;
93 	fb->height = mode_cmd->height;
94 	for (i = 0; i < 4; i++) {
95 		fb->pitches[i] = mode_cmd->pitches[i];
96 		fb->offsets[i] = mode_cmd->offsets[i];
97 	}
98 	fb->modifier = mode_cmd->modifier[0];
99 	fb->flags = mode_cmd->flags;
100 }
101 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
102 
103 /*
104  * This is the minimal list of formats that seem to be safe for modeset use
105  * with all current DRM drivers.  Most hardware can actually support more
106  * formats than this and drivers may specify a more accurate list when
107  * creating the primary plane.
108  */
109 static const uint32_t safe_modeset_formats[] = {
110 	DRM_FORMAT_XRGB8888,
111 	DRM_FORMAT_ARGB8888,
112 };
113 
114 static const struct drm_plane_funcs primary_plane_funcs = {
115 	DRM_PLANE_NON_ATOMIC_FUNCS,
116 };
117 
118 /**
119  * drm_crtc_init - Legacy CRTC initialization function
120  * @dev: DRM device
121  * @crtc: CRTC object to init
122  * @funcs: callbacks for the new CRTC
123  *
124  * Initialize a CRTC object with a default helper-provided primary plane and no
125  * cursor plane.
126  *
127  * Note that we make some assumptions about hardware limitations that may not be
128  * true for all hardware:
129  *
130  * 1. Primary plane cannot be repositioned.
131  * 2. Primary plane cannot be scaled.
132  * 3. Primary plane must cover the entire CRTC.
133  * 4. Subpixel positioning is not supported.
134  * 5. The primary plane must always be on if the CRTC is enabled.
135  *
136  * This is purely a backwards compatibility helper for old drivers. Drivers
137  * should instead implement their own primary plane. Atomic drivers must do so.
138  *
139  * Returns:
140  * Zero on success, error code on failure.
141  */
142 int drm_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
143 		  const struct drm_crtc_funcs *funcs)
144 {
145 	struct drm_plane *primary;
146 	int ret;
147 
148 	/* possible_crtc's will be filled in later by crtc_init */
149 	primary = __drm_universal_plane_alloc(dev, sizeof(*primary), 0, 0,
150 					      &primary_plane_funcs,
151 					      safe_modeset_formats,
152 					      ARRAY_SIZE(safe_modeset_formats),
153 					      NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
154 	if (IS_ERR(primary))
155 		return PTR_ERR(primary);
156 
157 	/*
158 	 * Remove the format_default field from drm_plane when dropping
159 	 * this helper.
160 	 */
161 	primary->format_default = true;
162 
163 	ret = drm_crtc_init_with_planes(dev, crtc, primary, NULL, funcs, NULL);
164 	if (ret)
165 		goto err_drm_plane_cleanup;
166 
167 	return 0;
168 
169 err_drm_plane_cleanup:
170 	drm_plane_cleanup(primary);
171 	kfree(primary);
172 	return ret;
173 }
174 EXPORT_SYMBOL(drm_crtc_init);
175 
176 /**
177  * drm_mode_config_helper_suspend - Modeset suspend helper
178  * @dev: DRM device
179  *
180  * This helper function takes care of suspending the modeset side. It disables
181  * output polling if initialized, suspends fbdev if used and finally calls
182  * drm_atomic_helper_suspend().
183  * If suspending fails, fbdev and polling is re-enabled.
184  *
185  * Returns:
186  * Zero on success, negative error code on error.
187  *
188  * See also:
189  * drm_kms_helper_poll_disable() and drm_client_dev_suspend().
190  */
191 int drm_mode_config_helper_suspend(struct drm_device *dev)
192 {
193 	struct drm_atomic_state *state;
194 
195 	if (!dev)
196 		return 0;
197 	/*
198 	 * Don't disable polling if it was never initialized
199 	 */
200 	if (dev->mode_config.poll_enabled)
201 		drm_kms_helper_poll_disable(dev);
202 
203 	drm_client_dev_suspend(dev);
204 	state = drm_atomic_helper_suspend(dev);
205 	if (IS_ERR(state)) {
206 		drm_client_dev_resume(dev);
207 
208 		/*
209 		 * Don't enable polling if it was never initialized
210 		 */
211 		if (dev->mode_config.poll_enabled)
212 			drm_kms_helper_poll_enable(dev);
213 
214 		return PTR_ERR(state);
215 	}
216 
217 	dev->mode_config.suspend_state = state;
218 
219 	return 0;
220 }
221 EXPORT_SYMBOL(drm_mode_config_helper_suspend);
222 
223 /**
224  * drm_mode_config_helper_resume - Modeset resume helper
225  * @dev: DRM device
226  *
227  * This helper function takes care of resuming the modeset side. It calls
228  * drm_atomic_helper_resume(), resumes fbdev if used and enables output polling
229  * if initiaized.
230  *
231  * Returns:
232  * Zero on success, negative error code on error.
233  *
234  * See also:
235  * drm_client_dev_resume() and drm_kms_helper_poll_enable().
236  */
237 int drm_mode_config_helper_resume(struct drm_device *dev)
238 {
239 	int ret;
240 
241 	if (!dev)
242 		return 0;
243 
244 	if (WARN_ON(!dev->mode_config.suspend_state))
245 		return -EINVAL;
246 
247 	ret = drm_atomic_helper_resume(dev, dev->mode_config.suspend_state);
248 	if (ret)
249 		DRM_ERROR("Failed to resume (%d)\n", ret);
250 	dev->mode_config.suspend_state = NULL;
251 
252 	drm_client_dev_resume(dev);
253 
254 	/*
255 	 * Don't enable polling if it is not initialized
256 	 */
257 	if (dev->mode_config.poll_enabled)
258 		drm_kms_helper_poll_enable(dev);
259 
260 	return ret;
261 }
262 EXPORT_SYMBOL(drm_mode_config_helper_resume);
263