Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2016 Noralf Trønnes
4 */
5
6#include <drm/drm_atomic_helper.h>
7#include <drm/drm_drv.h>
8#include <drm/drm_gem_framebuffer_helper.h>
9#include <drm/drm_modes.h>
10#include <drm/drm_probe_helper.h>
11#include <drm/drm_print.h>
12#include <drm/drm_simple_kms_helper.h>
13
14struct tinydrm_connector {
15 struct drm_connector base;
16 struct drm_display_mode mode;
17};
18
19static inline struct tinydrm_connector *
20to_tinydrm_connector(struct drm_connector *connector)
21{
22 return container_of(connector, struct tinydrm_connector, base);
23}
24
25static int tinydrm_connector_get_modes(struct drm_connector *connector)
26{
27 struct tinydrm_connector *tconn = to_tinydrm_connector(connector);
28 struct drm_display_mode *mode;
29
30 mode = drm_mode_duplicate(connector->dev, &tconn->mode);
31 if (!mode) {
32 DRM_ERROR("Failed to duplicate mode\n");
33 return 0;
34 }
35
36 if (mode->name[0] == '\0')
37 drm_mode_set_name(mode);
38
39 mode->type |= DRM_MODE_TYPE_PREFERRED;
40 drm_mode_probed_add(connector, mode);
41
42 if (mode->width_mm) {
43 connector->display_info.width_mm = mode->width_mm;
44 connector->display_info.height_mm = mode->height_mm;
45 }
46
47 return 1;
48}
49
50static const struct drm_connector_helper_funcs tinydrm_connector_hfuncs = {
51 .get_modes = tinydrm_connector_get_modes,
52};
53
54static enum drm_connector_status
55tinydrm_connector_detect(struct drm_connector *connector, bool force)
56{
57 if (drm_dev_is_unplugged(connector->dev))
58 return connector_status_disconnected;
59
60 return connector->status;
61}
62
63static void tinydrm_connector_destroy(struct drm_connector *connector)
64{
65 struct tinydrm_connector *tconn = to_tinydrm_connector(connector);
66
67 drm_connector_cleanup(connector);
68 kfree(tconn);
69}
70
71static const struct drm_connector_funcs tinydrm_connector_funcs = {
72 .reset = drm_atomic_helper_connector_reset,
73 .detect = tinydrm_connector_detect,
74 .fill_modes = drm_helper_probe_single_connector_modes,
75 .destroy = tinydrm_connector_destroy,
76 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
77 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
78};
79
80struct drm_connector *
81tinydrm_connector_create(struct drm_device *drm,
82 const struct drm_display_mode *mode,
83 int connector_type)
84{
85 struct tinydrm_connector *tconn;
86 struct drm_connector *connector;
87 int ret;
88
89 tconn = kzalloc(sizeof(*tconn), GFP_KERNEL);
90 if (!tconn)
91 return ERR_PTR(-ENOMEM);
92
93 drm_mode_copy(&tconn->mode, mode);
94 connector = &tconn->base;
95
96 drm_connector_helper_add(connector, &tinydrm_connector_hfuncs);
97 ret = drm_connector_init(drm, connector, &tinydrm_connector_funcs,
98 connector_type);
99 if (ret) {
100 kfree(tconn);
101 return ERR_PTR(ret);
102 }
103
104 connector->status = connector_status_connected;
105
106 return connector;
107}
108
109static int tinydrm_rotate_mode(struct drm_display_mode *mode,
110 unsigned int rotation)
111{
112 if (rotation == 0 || rotation == 180) {
113 return 0;
114 } else if (rotation == 90 || rotation == 270) {
115 swap(mode->hdisplay, mode->vdisplay);
116 swap(mode->hsync_start, mode->vsync_start);
117 swap(mode->hsync_end, mode->vsync_end);
118 swap(mode->htotal, mode->vtotal);
119 swap(mode->width_mm, mode->height_mm);
120 return 0;
121 } else {
122 return -EINVAL;
123 }
124}
125
126/**
127 * tinydrm_display_pipe_init - Initialize display pipe
128 * @drm: DRM device
129 * @pipe: Display pipe
130 * @funcs: Display pipe functions
131 * @connector_type: Connector type
132 * @formats: Array of supported formats (DRM_FORMAT\_\*)
133 * @format_count: Number of elements in @formats
134 * @mode: Supported mode
135 * @rotation: Initial @mode rotation in degrees Counter Clock Wise
136 *
137 * This function sets up a &drm_simple_display_pipe with a &drm_connector that
138 * has one fixed &drm_display_mode which is rotated according to @rotation.
139 *
140 * Returns:
141 * Zero on success, negative error code on failure.
142 */
143int tinydrm_display_pipe_init(struct drm_device *drm,
144 struct drm_simple_display_pipe *pipe,
145 const struct drm_simple_display_pipe_funcs *funcs,
146 int connector_type,
147 const uint32_t *formats,
148 unsigned int format_count,
149 const struct drm_display_mode *mode,
150 unsigned int rotation)
151{
152 struct drm_display_mode mode_copy;
153 struct drm_connector *connector;
154 int ret;
155 static const uint64_t modifiers[] = {
156 DRM_FORMAT_MOD_LINEAR,
157 DRM_FORMAT_MOD_INVALID
158 };
159
160 drm_mode_copy(&mode_copy, mode);
161 ret = tinydrm_rotate_mode(&mode_copy, rotation);
162 if (ret) {
163 DRM_ERROR("Illegal rotation value %u\n", rotation);
164 return -EINVAL;
165 }
166
167 drm->mode_config.min_width = mode_copy.hdisplay;
168 drm->mode_config.max_width = mode_copy.hdisplay;
169 drm->mode_config.min_height = mode_copy.vdisplay;
170 drm->mode_config.max_height = mode_copy.vdisplay;
171
172 connector = tinydrm_connector_create(drm, &mode_copy, connector_type);
173 if (IS_ERR(connector))
174 return PTR_ERR(connector);
175
176 return drm_simple_display_pipe_init(drm, pipe, funcs, formats,
177 format_count, modifiers, connector);
178}
179EXPORT_SYMBOL(tinydrm_display_pipe_init);