xref: /linux/drivers/gpu/drm/drm_modeset_helper.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
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 <drm/drm_modeset_helper.h>
24 #include <drm/drm_plane_helper.h>
25 
26 /**
27  * DOC: aux kms helpers
28  *
29  * This helper library contains various one-off functions which don't really fit
30  * anywhere else in the DRM modeset helper library.
31  */
32 
33 /**
34  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
35  * 						connector list
36  * @dev: drm device to operate on
37  *
38  * Some userspace presumes that the first connected connector is the main
39  * display, where it's supposed to display e.g. the login screen. For
40  * laptops, this should be the main panel. Use this function to sort all
41  * (eDP/LVDS/DSI) panels to the front of the connector list, instead of
42  * painstakingly trying to initialize them in the right order.
43  */
44 void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
45 {
46 	struct drm_connector *connector, *tmp;
47 	struct list_head panel_list;
48 
49 	INIT_LIST_HEAD(&panel_list);
50 
51 	spin_lock_irq(&dev->mode_config.connector_list_lock);
52 	list_for_each_entry_safe(connector, tmp,
53 				 &dev->mode_config.connector_list, head) {
54 		if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
55 		    connector->connector_type == DRM_MODE_CONNECTOR_eDP ||
56 		    connector->connector_type == DRM_MODE_CONNECTOR_DSI)
57 			list_move_tail(&connector->head, &panel_list);
58 	}
59 
60 	list_splice(&panel_list, &dev->mode_config.connector_list);
61 	spin_unlock_irq(&dev->mode_config.connector_list_lock);
62 }
63 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
64 
65 /**
66  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
67  * @dev: DRM device
68  * @fb: drm_framebuffer object to fill out
69  * @mode_cmd: metadata from the userspace fb creation request
70  *
71  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
72  * metadata fields.
73  */
74 void drm_helper_mode_fill_fb_struct(struct drm_device *dev,
75 				    struct drm_framebuffer *fb,
76 				    const struct drm_mode_fb_cmd2 *mode_cmd)
77 {
78 	int i;
79 
80 	fb->dev = dev;
81 	fb->format = drm_format_info(mode_cmd->pixel_format);
82 	fb->width = mode_cmd->width;
83 	fb->height = mode_cmd->height;
84 	for (i = 0; i < 4; i++) {
85 		fb->pitches[i] = mode_cmd->pitches[i];
86 		fb->offsets[i] = mode_cmd->offsets[i];
87 	}
88 	fb->modifier = mode_cmd->modifier[0];
89 	fb->flags = mode_cmd->flags;
90 }
91 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
92 
93 /*
94  * This is the minimal list of formats that seem to be safe for modeset use
95  * with all current DRM drivers.  Most hardware can actually support more
96  * formats than this and drivers may specify a more accurate list when
97  * creating the primary plane.  However drivers that still call
98  * drm_plane_init() will use this minimal format list as the default.
99  */
100 static const uint32_t safe_modeset_formats[] = {
101 	DRM_FORMAT_XRGB8888,
102 	DRM_FORMAT_ARGB8888,
103 };
104 
105 static struct drm_plane *create_primary_plane(struct drm_device *dev)
106 {
107 	struct drm_plane *primary;
108 	int ret;
109 
110 	primary = kzalloc(sizeof(*primary), GFP_KERNEL);
111 	if (primary == NULL) {
112 		DRM_DEBUG_KMS("Failed to allocate primary plane\n");
113 		return NULL;
114 	}
115 
116 	/*
117 	 * Remove the format_default field from drm_plane when dropping
118 	 * this helper.
119 	 */
120 	primary->format_default = true;
121 
122 	/* possible_crtc's will be filled in later by crtc_init */
123 	ret = drm_universal_plane_init(dev, primary, 0,
124 				       &drm_primary_helper_funcs,
125 				       safe_modeset_formats,
126 				       ARRAY_SIZE(safe_modeset_formats),
127 				       DRM_PLANE_TYPE_PRIMARY, NULL);
128 	if (ret) {
129 		kfree(primary);
130 		primary = NULL;
131 	}
132 
133 	return primary;
134 }
135 
136 /**
137  * drm_crtc_init - Legacy CRTC initialization function
138  * @dev: DRM device
139  * @crtc: CRTC object to init
140  * @funcs: callbacks for the new CRTC
141  *
142  * Initialize a CRTC object with a default helper-provided primary plane and no
143  * cursor plane.
144  *
145  * Returns:
146  * Zero on success, error code on failure.
147  */
148 int drm_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
149 		  const struct drm_crtc_funcs *funcs)
150 {
151 	struct drm_plane *primary;
152 
153 	primary = create_primary_plane(dev);
154 	return drm_crtc_init_with_planes(dev, crtc, primary, NULL, funcs,
155 					 NULL);
156 }
157 EXPORT_SYMBOL(drm_crtc_init);
158